Clinical Laboratory Immunology, 1st Edition Test Bank
Get ahead in your studies with Clinical Laboratory Immunology, 1st Edition Test Bank, featuring exam-focused questions and solutions.
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ExamName___________________________________MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.1)Which of the following defines commensalism?1)A)Biologic relationship between two organisms in which one benefits and the other is harmed.B)Biologic relationship between two organisms in which both are harmed.C)Biologic relationship between two organisms in which both benefit.D)Biologic relationship between two organisms in which one benefits and the other remainsunharmed.Answer:D2)Microbes that colonize a particular person for a long period of time are called2)A)nonpathogenic microbial flora.B)usual microbial flora.C)transient microbial flora.D)resident microbial flora.Answer:D3)Each body site below is pairedcorrectlywith an expected component of the normal microbial floraexcept3)A)colon/enterobacteriaceae.B)vagina/lactobacilli.C)upper respiratory tract/viridians streptococci and diphtheroids.D)skin/Staph epidermisandPropionibacterium.E)All of the above are paired correctly.Answer:E4)Normal microbial skin flora is primarily concentrated on the4)A)dry areas of skin with heavy hair.B)moist areas of skin near sweat glands.C)dry areas of skin with light hair.D)fingernails and toenails.Answer:B5)What is the collective purpose of nasal hair, mucus secretions in the naspopharyngeal tract,phagocytic cells in the throat, bronchial lysozyme, sneezing, and coughing?5)A)To keep organisms from entering the lower respiratory tract and causing infection.B)To keep normal flora in the oropharynx from entering the eustachian tube causing infection.C)To keep normal flora in the oropharynx from causing infection.D)To maintain a sterile environment in the oropharynx.Answer:A6)Quantitatively, the most important defense against food-borne pathogens in the gastrointestinaltract is6)A)peristaltic movement.B)ciliated cells.C)mucus cells.D)resident phagocytic cells.E)low pH and high enzymatic content of the stomach.Answer:E1
ExamName___________________________________MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.1)Which of the following defines commensalism?1)A)Biologic relationship between two organisms in which one benefits and the other is harmed.B)Biologic relationship between two organisms in which both are harmed.C)Biologic relationship between two organisms in which both benefit.D)Biologic relationship between two organisms in which one benefits and the other remainsunharmed.Answer:D2)Microbes that colonize a particular person for a long period of time are called2)A)nonpathogenic microbial flora.B)usual microbial flora.C)transient microbial flora.D)resident microbial flora.Answer:D3)Each body site below is pairedcorrectlywith an expected component of the normal microbial floraexcept3)A)colon/enterobacteriaceae.B)vagina/lactobacilli.C)upper respiratory tract/viridians streptococci and diphtheroids.D)skin/Staph epidermisandPropionibacterium.E)All of the above are paired correctly.Answer:E4)Normal microbial skin flora is primarily concentrated on the4)A)dry areas of skin with heavy hair.B)moist areas of skin near sweat glands.C)dry areas of skin with light hair.D)fingernails and toenails.Answer:B5)What is the collective purpose of nasal hair, mucus secretions in the naspopharyngeal tract,phagocytic cells in the throat, bronchial lysozyme, sneezing, and coughing?5)A)To keep organisms from entering the lower respiratory tract and causing infection.B)To keep normal flora in the oropharynx from entering the eustachian tube causing infection.C)To keep normal flora in the oropharynx from causing infection.D)To maintain a sterile environment in the oropharynx.Answer:A6)Quantitatively, the most important defense against food-borne pathogens in the gastrointestinaltract is6)A)peristaltic movement.B)ciliated cells.C)mucus cells.D)resident phagocytic cells.E)low pH and high enzymatic content of the stomach.Answer:E1
7)A microorganism that typically does not cause disease in a normal host but that does cause diseaseif the host is compromised in some way is called7)A)symbiotic.B)commensal.C)opportunistic.D)parasitic.E)pathogenic.Answer:C8)Which of the following situation(s) represents an event that could result in an opportunisticinfection?8)A)Subject is stabbed with a knife.B)Subject has dental surgery.C)Subject has leukemia.D)Subject is undergoing radiation for cancer treatment.E)All of the above.Answer:E9)A microorganism that consistently causes disease in normal people with competent immunesystems is a9)A)virulent pathogen.B)opportunistic pathogen.C)commensal pathogen.D)true pathogen.E)symbiotic pathogen.Answer:D10)Which of the following are mechanisms by which microbes evade phagocytosis?10)A)Produce collagenaseB)Produce leukocidinsC)Produce hyaluronidasesD)MotilityAnswer:B11)Which microbial product below helps organisms penetrate tissues?11)A)HemolysinsB)HyaluronidaseC)CapsuleD)FimbraeE)CoagulaseAnswer:B12)Which microbial product below helpsStaphylococcus aureuscreate a protective fibrin wall arounditself?12)A)FimbraeB)CapsuleC)CoagulaseD)HyaluronidaseE)HemolysinsAnswer:C2
7)A microorganism that typically does not cause disease in a normal host but that does cause diseaseif the host is compromised in some way is called7)A)symbiotic.B)commensal.C)opportunistic.D)parasitic.E)pathogenic.Answer:C8)Which of the following situation(s) represents an event that could result in an opportunisticinfection?8)A)Subject is stabbed with a knife.B)Subject has dental surgery.C)Subject has leukemia.D)Subject is undergoing radiation for cancer treatment.E)All of the above.Answer:E9)A microorganism that consistently causes disease in normal people with competent immunesystems is a9)A)virulent pathogen.B)opportunistic pathogen.C)commensal pathogen.D)true pathogen.E)symbiotic pathogen.Answer:D10)Which of the following are mechanisms by which microbes evade phagocytosis?10)A)Produce collagenaseB)Produce leukocidinsC)Produce hyaluronidasesD)MotilityAnswer:B11)Which microbial product below helps organisms penetrate tissues?11)A)HemolysinsB)HyaluronidaseC)CapsuleD)FimbraeE)CoagulaseAnswer:B12)Which microbial product below helpsStaphylococcus aureuscreate a protective fibrin wall arounditself?12)A)FimbraeB)CapsuleC)CoagulaseD)HyaluronidaseE)HemolysinsAnswer:C2
13)The microbial structures that promote attachment of the microbe to tissues, making phagocytosismore difficult, are13)A)Panton-Valentines.B)fimbrae.C)cell walls.D)capsules.E)flagella.Answer:B14)Which organism below produces a protein called Protein A that binds to the Fc portion of IgG?14)A)ChlamydiaB)Hemophilus influenzaeC)Streptococcus pyogenesD)Streptococcus pneumoniaeE)Staphylococcus aureusAnswer:E15)Which organism below is easily phagocytized but is capable of surviving and multiplyingintracellularly?15)A)Staphylococcus aureusB)Streptococcus pyogenesC)Hemophilus influenzaeD)ChlamydiaE)Streptococcus pneumoniaeAnswer:D16)All of the following organisms are virulent at least in part due to exotoxins they secreteexcept16)A)Staphylococcus aureusB)Mycobacterium tuberculosisC)Streptococcus pyogenesD)Corynebacterium diphtheriaeE)Clostridium botulinumAnswer:B17)Which of the following antimicrobial substance is(are) secreted by mucous membranes?17)A)LactoferrinB)LysozymeC)AntibodiesD)All of the aboveAnswer:D18)Phagocytes are most effective against18)A)protozoan parasites.B)extracellular bacteria.C)intracellular viruses.D)Phagocytes are equally effective against all the microbes listed.E)intracellular bacteria.Answer:B3
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19)Which of the following can function as chemotactic agents?19)A)Complement fragmentsB)Bacterial productsC)Cytokines produced by white blood cells responding to an inflammatory siteD)Mediators released from damaged tissueE)All of the aboveAnswer:E20)Release of inflammatory mediators causes increased vascular permeability. Which of the fourhallmarks of inflammation does this cause?20)A)HeatB)ErythemaC)PusD)PainE)EdemaAnswer:E21)When an infection occurs in a fetus or early in the life of the neonate, the immune response may beinadequate due to21)A)the induction of tolerance.B)suppression of the immune system.C)interference from maternal T cells.D)antigenic variation.Answer:A22)What do infections with HIV, cytomegalovirus, and Epstein-Barr virus all have in common?22)A)Evasion of the immune system by antigenic variation.B)An induction of immune tolerance to other viruses.C)Poor production of antibody by the host.D)Immunosuppression of the host.Answer:D23)Which organism below evades the adaptive immune response by antigenic variation?23)A)Borrelia recurrentisB)Plasmodium vivaxC)Brucella abortisD)Listeria monocytogenesE)Mycobacterium tuberculosisAnswer:A24)Which organism below evades the adaptive immune response by surviving inside host liver cells?24)A)Mycobacterium tuberculosisB)Borrelia recurrentisC)Listeria monocytogenesD)Plasmodium vivaxE)Brucella abortisAnswer:D25)An important feature of many pathogenic viruses is their resistance to25)A)lysozyme.B)interferon.C)interleukin-2.D)interleukin-1.E)lactoferrin.Answer:B4
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SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.26)Discuss how the nature of a particular body site influences the normal microbial floralocated there.26)Answer:In order to colonize a particular body site, a microorganism must be able to evadethe normal defense mechanisms and exploit the local conditions to survive. Thus,areas of the body with low oxygen, such as the gum crevices around the teeth, cansupport anaerobes that are resistant to antimicrobial substances such as lysozyme inthe saliva. Secreted fatty acids on the skin are normally antimicrobial, butPropionibacteriumspecies can metabolize them. Females of reproductive age secreteglycogen vaginally, allowing lactobacilli to flourish. Breast-fed babies have lowerpH in the gastrointestinal tract, and acid-tolerant species such asBifidobacteriumcolonize.27)Discuss the benefits of normal microbial flora for the host.27)Answer:Newborns normally existed in a sterile environment up until their birth, so theexposure to nonpathogenic organisms is the first stimulation to their immunesystems and is a necessary step in the development of a fully functional immunesystem. The other advantage the normal flora provide is competition withpathogens for limited space and nutrients on the host, and antibiotics that kill offlarge numbers of normal flora actually make the hostmoresusceptible to pathogens.28)Differentiate virulence and pathogenicity.28)Answer:If an organism is capable of causing a disease in a particular body site or situation, itis a potential pathogen. Thus, a normally nonpathogenic organism can be apathogen in an compromised host. A very virulent pathogen is easily acquiredand/or has very serious outcomes, including death by uncompromised people withnormal immune systems.29)List ways in which the skin resists the penetration of microorganisms.29)Answer:1. Physical barrier of keratinized skin2. Bacteriocidal substances secreted by sebaceous glands3. Normal flora—low pH, competition for nutrients and space4. Constant shedding of outermost skin layer—reduces microbial load30)List ways in which microorganisms evade phagocytosis.30)Answer:1. Production of protein that binds to Fc portion of IgG (e.g.,Staph aureus)2. Possess capsule (e.g.,Streptococcus pneumoniae)3. Adhere to host cells via fimbrae (e.g.,Streptococcus pyogenes)4. Produce leukocidins and hemolysins (toxic to WBCs)5. Produce coagulase to protect themselves with fibrin wall (e.g.,Staph aureus)TRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false.31)Normal microbial flora never cause disease in immunocompetent hosts.31)Answer:TrueFalse5
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32)A Boy Scout goes camping in the woods for a week and doesn't take a shower. When he gets home,the microbes that he carried all week long are washed away in the shower, never to return. Themicrobes that the boy acquired in the woods and carried all week would be called transientmicrobial flora.32)Answer:TrueFalse33)A particular microorganism may be commensal in one body site but parasitic in another body site.33)Answer:TrueFalse34)A human could never harbor a pathogenic microorganism as resident flora.34)Answer:TrueFalse35)No microorganism is capable of directly penetrating keratinized, intact human skin.35)Answer:TrueFalse36)The movement of white blood cells through blood vessel walls is called chemotaxis.36)Answer:TrueFalse37)Erythema in an inflamed site is caused by release of inflammatory mediators that increase bloodflow to the affected area.37)Answer:TrueFalse38)People with immune systems suppressed by HIV are more susceptible to viral, fungal, andprotozoal infections.38)Answer:TrueFalse39)Some organisms evade the immune response by changing the antigens expressed on their surfaceduring the course of an infection.39)Answer:TrueFalse40)Once an organism is engulfed by macrophage, it is always digested and killed.40)Answer:TrueFalseSHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.41)Microorganisms that are consistently associated with human disease are called ________.41)Answer:pathogens42)Antibiotic associated colitis has been associated with the organism ________.42)Answer:Clostridium difficile43)Microbes that have very low infective doses and/or that are very harmful to the host arevery ________.43)Answer:virulent44)Microorganisms with capsules are better able to evade ________ by neutrophils andmonocytes.44)Answer:phagocytosis6
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45)The causative organism of botulism is particularly virulent because of the ________ itsecretes.45)Answer:exotoxin7
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ExamName___________________________________MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.1)The products of the major histocompatibility complex that are responsible for tissue type are called________ because they were initially identified on white blood cells.1)A)leukocyte thymic education antigensB)Gorer white antigensC)human leukocyte antigensD)Landsteiner leukocyte markersAnswer:C2)What role do HLA (MHC) antigens play in the thymus?2)A)Selection of T cell clones that bind to foreign antigenB)Selection of T cell clones capable of binding to HLA (MHC) antigensC)Elimination of autoreactive T cell clonesD)All of the aboveAnswer:D3)The proteins of the HLA system are said to belong to the ________ superfamily because most havea constant and variable region.3)A)immunoglobulinB)complementC)immune receptorD)autoantigenAnswer:A4)In what manner are MHC genes expressed?4)A)ActivatedB)SilentC)DominantD)CodominantE)RecessiveAnswer:D5)Which of the following is true regarding inheritance of MHC genes?5)A)Alleles can be homozygous or heterozygous.B)Inheritance of MHC genes follows Mendelian genetics (Law of Segregation or Law ofIndependent Assortment).C)The rate of gene recombination is low, but there are some "hot spots" of increasedrecombination.D)All of the above.Answer:D6)Which set of HLA gene(s) is considered the "classic" set of Class I MHC molecules?6)A)HLA A, B, and CB)classic complement componentsC)HLA DP, DQ, and DRD)beta 2 microglobulinE)alpha/beta heterodimerAnswer:A1
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7)What is the best current technology for determining HLA types?7)A)Flow cytometry detecting mixed lymphocyte cytotoxicity reactions.B)Flow cytometry using labeled antibodies to cell surface antigens.C)Molecular determination of which HLA alleles are in the DNA.D)Molecular determination of which HLA alleles are expressed by the RNA.Answer:C8)All of the following cell types express Class I MHC antigensexcept8)A)mature red blood cells.B)mature lymphocytes.C)brain cells.D)platelets.E)differentiated muscle cells.Answer:A9)Why are red blood cell transfusions not rejected in the same way that transplanted tissues are?9)A)MHC Class II molecules are unstable on red blood cells once they are removed from the body.B)Mature red blood cells do not express MHC Class II.C)Mature red blood cells do not express MHC Class I.D)Refrigerator storage of red blood cells inactivates both MHC Class II and I.E)MHC Class I molecules are unstable on red blood cells once they are removed from the body.Answer:C10)Which of the following is TRUE of both MHC Class I and II receptors?10)A)nonfunctional if alpha and beta chains are not properly associated.B)heterodimers composed of alpha and beta chains.C)alpha chain similar in structure to an immunoglobulin heavy chain and beta chain similar instructure to an immunoglobulin light chain.D)necessary to present foreign antigen to lymphocytes.E)All of the above are true.Answer:E11)What is beta-2-microglobulin?11)A)The beta chain of the Class II MHC moleculeB)The alpha chain of the Class I MHC moleculeC)The alpha chain of the Class II MHC moleculeD)The beta chain of the Class I MHC moleculeAnswer:D12)Which of the following cell types isnotassociated with MHC Class II expression?12)A)LymphocytesB)MacrophagesC)Dendritic cellsD)Muscle tissueE)MonocytesAnswer:D2
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13)An important component of the immune response that Class III MHC genes code for is13)A)immunoglobulins.B)complement components.C)lysozyme.D)interferon.E)myeloperoxidase.Answer:B14)What antigen(s) are Class I and II MHC molecules capable of presenting to T cells?14)A)Antigens endogeneous to the normal host cellB)Antigens digested from phagocytized materialC)Antigens produced by viruses inside the host cellD)All of the aboveAnswer:D15)When foreign tissue is transplanted, the recipient's T cells react against15)A)public epitopes.B)private epitopes.C)alloepitopes.D)All of the above.Answer:D16)Panel reactive antibody (PRA) testing in organ transplantation is a system to test16)A)organ donors for preexisting HLA-primed T cytotoxic cells.B)organ recipients for preexisting HLA-primed T cytotoxic cells.C)organ recipients for preexisting HLA antibodies.D)organ donors for preexisting HLA antibodies.Answer:C17)All the following are contraindications to harvesting organs from a particular donorexcept17)A)cardiac activity.B)presence of antibodies to human immunodeficiency virus.C)presence of metastatic carcinoma.D)neurologic activity.Answer:A3
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18)A donor organ has the following HLA and ABO types:A positiveHLA type—A1, A3, B4, B5, DR 6, DR7Observe the potential recipient information below. Based on UNOS criteria, which recipient should receivethis organ?18)A)Recipient 4—47 years old, never received an organCurrent medical condition—poorA positiveHLA type—A1, A3, B4, B10, DR 6, DR7Panel reactive antibodies—positive; cross-match with donor tissue positiveTime on waiting list—15 yearsB)Recipient 2—5 years old, never received an organCurrent medical condition—stableA positiveHLA type—A2, A3, B4, B5, DR 6, DR9Panel reactive antibodies—negativeTime on waiting list—1 yearC)Recipient 1—65 years old, never received an organCurrent medical condition—poorB positiveHLA type—A1, A3, B4, B5, DR 6, DR7Panel reactive antibodies—negativeTime on waiting list—5 yearsD)Recipient 3—29 years old, received an organ 2 years ago and has rejected itCurrent medical condition—poorO positiveHLA type—A2, A3, B1, B5, DR 6, DR7Panel reactive antibodies—negativeTime on waiting list—2 yearsAnswer:B19)Which of the following is(are) used to transplant progenitor cells (pluripotent stem cells)?19)A)Growth factor stimulated peripheral bloodB)Umbilical cord bloodC)Bone marrowD)All of the aboveAnswer:D20)In order to transplant allogeneic progenitor (stem) cells, the recipient must20)A)have a normal immune system.B)be completely immunodeficient.C)be on immunosuppressive therapy.D)be cytokine stimulated to promote engraftment.Answer:B4
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21)Which of the following patients is a candidate for autologous progenitor (stem) cell transplant?18021)A)Breast cancer patientB)Multiple myeloma patientC)Acute myelogeneous leukemia patientD)Patient with severe combined immune deficiency disease (SCID) cause by genetic ADAdeficiencyE)Sickle cell anemia patientAnswer:A22)Which statement below best summarizes how information regarding a patient's HLA type is usedwith respect to diseases associated with specific HLA types?22)A)Odds ratios can be calculated for certain HLA types and the diseases with which they areassociated. This is used as supplemental information in diagnosis and counseling.B)HLA typing is done to exclude the presence of a disease and is an important part of diagnosis.C)HLA typing is done to confirm the presence of a disease and is an important part of diagnosis.D)HLA associations with diseases are so unreliable that they are never used in diagnosis.Answer:A23)Patients with seronegative inflammatory joint problems could benefit from HLA typing to see ifthey are ________ positive.23)A)A1B)DQ1C)A56D)B11E)B27Answer:E24)Certain HLA types have been associated with the progression of ________.24)A)rheumatoid arthritis.B)systemic lupus erythematosus.C)herpes varicella zoster (chicken pox).D)AIDS.Answer:D25)People with the HLA haplotype A1, B8, DR3 have an increased nonresponse rate to which vaccine?25)A)PolioB)Hepatitis B virus (HBV)C)Measles/mumps/rubella (MMR)D)Influenza virusE)Diptheria/pertussis/tetanus (DPT)Answer:BSHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.26)The cluster of genes found on the short arm of chromosome 6 that determine "tissue type"is called ________.26)Answer:major histocompatibility complex (MHC)27)The number of alleles for genes present in the major histocompatibility complex make thisthe most ________ set of human genes ever identified.27)Answer:polymorphic28)When T cells do not recognize an antigen presented by a cell in conjunction with MHCClass I or II molecules, this is called ________.28)Answer:tolerance5
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29)Transplants are most successful if the recipient is both ________ and ________ compatiblewith the donor's tissue29)Answer:HLA , ABO30)The HLA types DR2 and DQ1 are associated with ________.30)Answer:narcolepsyTRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false.31)One of the reasons that compatible organs for transplantation are so difficult to find is that there isa relatively high rate of recombination in the MHC genes.31)Answer:TrueFalse32)The probability that two siblings from the same parents have identical HLA types is 25%.32)Answer:TrueFalse33)MHC Class I expression in a particular cell type remains constant through that cell's life cycle onceit matures.33)Answer:TrueFalse34)MHC pseudogenes express alpha and beta MHC receptor chains that are similar to heavy and lightimmunoglobulin chains.34)Answer:TrueFalse35)Organs for transplant in the United States are allocated based on which person on the waiting list isthe sickest.35)Answer:TrueFalse36)The final decision as to whether a person receives a particular organ for transplant in the UnitedStates is made by UNOS (United Network of Organ Sharing).36)Answer:TrueFalse37)The best donor for progenitor (stem) cell transplantation if the recipient himself.37)Answer:TrueFalse38)The greatest immediate risk after allogeneic progenitor (stem) cell transplant is graft versus hostdisease.38)Answer:TrueFalse39)There is no benefit from graft versus host disease to any patient population.39)Answer:TrueFalse40)To date, the strongest association of an HLA type with a disease is the association of 5-CREG withHodgkin's disease.40)Answer:TrueFalse6
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SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.41)Explain why as a general rule a child's HLA type is only 50% identical to his father's and50% identical to his mother's.41)Answer:Each parent has two sets of MHC genes, and because of the polymorphism of theMHC system, these gene sets would virtually never be identical. Each child gets oneof those two sets from each parent. Because the genes are closely linked, they areusually inherited intact*by classic Mendelian genetics (Law of Segregation or Law ofIndependent Assortment). The inherited alleles are expressed codominantly, meaning thatboth the mother's and the father's genes are expressed and to equal degrees. The followingexample shows that any possible child would only have 50% of a parent's HLA type.Mother's genotype=a and b Father's genotype=c and dPossible children=a and c, a and d, b and c, b and d*The recombination rate of the HLA genes is only about 2%.42)Explain linkage disequilibrium and how it relates to predicting the frequency of particularHLA alleles.42)Answer:Example: An organ transplant candidate inherited MHC gene set A from his mother andMHC gene set B from his father. An organ must be found that has both A and B MHCgenes. If the frequency of A in the general population is 1% and the frequency of B is 1%than the predicted probability of finding the two together isfrequency of A x frequency of B=0.01 x 0.01=0.0001 or 1 in 10,000In many cases, the prediction illustrated above is wrong, and in certain populations theincidence of particular gene combinations is higher than predicted. This is called linkagedisequilibrium. Since many examples of linkage disequilibrium seem to be related toethnicity and/or nationality, knowledge of the gene pool in various ethnic populations canbe useful to more easily identify compatible donors.43)Describe the composition of the Class I MHC molecule on a cell's surface.43)Answer:The Class I MHC molecule is composed of an alpha chain and a beta chain complex.The alpha chain spans the cell membrane with an external domain, atransmembrane domain, and an internal domain. The alpha chain is similar instructure to a heavy chain immunoglobulin molecule. The beta chain, also calledbeta-2-microglobulin, is similar in structure to a light chain immunoglobulinmolecule, but its structure is constant and highly conserved. The external domain ofthe Class I molecule is used to present foreign antigen to T cytotoxic cells.7
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44)Discuss the nomenclature of the HLA alleles.44)Answer:Initially, the HLA A and B genes were numbered sequentially as they werediscovered (e.g., HLA B2). Newly discovered genes were given the provisionaldesignation "w" until it was certain that the discoveries were genuine (e.g., HLABw2). To prevent confusion between the HLA complement genes and the HLA Cgenes, the "w" designation was permanently given to all HLA C genes. As typingmethods became more sophisticated, the specificities of different alleles becomemore defined, and epitopes shared by different alleles were identified. Somepreviously identified allele epitopes were characterized as "splits" when two ormore individual epitopes were found to be components of the original epitopes.This means that related epitopes may not be numbered consecutively and that evermore sophisticated nomenclature for the alleles is developing.45)Discuss the optimal circumstances to approach a family about organ donation.45)Answer:The facility should first verify that the prospective donor meets all the criterianecessary for donation. The family should be notified that the donor will notsurvive, and they should be given some time to assimilate that information. A healthcare provider who has previously interacted successfully with the family shouldgather the family in a private room away from the bedside to discuss the possibilityof organ donation.8
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ExamName___________________________________MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.1)The regulatory body for HLA testing for transplant programs is1)A)College of American Pathologists.B)Foundation for the Accreditation of Cellular Therapy.C)American Society of Histocompatibility and Immunogenetics.D)United Network for Organ Sharing.Answer:C2)The complement dependent cytotoxicity method of HLA testing can be used for2)A)cross-matching recipient plasma with donor cells.B)HLA typing of Class I antigens.C)identifying recipient HLA antibodies.D)HLA typing of Class II antigens.E)All of the above.Answer:E3)Which of the following is (are) TRUE regarding acceptable specimens for HLA typing byserological methods?3)A)Lithium heparin is the anticoagulant of choice for HLA typing.B)Peripheral blood, spleen tissue, and lymph node tissue can all be used for HLA typing.C)Specimens should be stored at 2–6° C after collection.D)Specimens preserved in sodium heparin or acid citrate dextrose are acceptable for up to oneweek after collection.E)All of the above.Answer:B4)Can sodium oxalate and EDTA be used for HLA typing, antibody identification, andcross-matching by conventional serologic methods?4)A)Yes, as long as the specimen is kept at room temperature.B)Yes, as long as the specimen is kept at 2–6° C.C)No, because EDTA and oxalate chelate Mg++and Ca++.D)No, because EDTA and oxalate are toxic to white blood cells.Answer:C5)The Ficoll Hypaque technique isolates mononuclear cells by5)A)cell surface marker affinity.B)cellular adherence.C)cell membrane solubility.D)cell density.Answer:D6)How can monocytes be removed from lymphocyte preparations?6)A)Washing Ficoll-Hypaque density separation with 5% ethanolB)Specific monocyte destruction with monoclonal antibodiesC)Adding iron filings for monocyte phagocytosisD)A and BE)B and CAnswer:E1
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7)Class II HLA antigens are best determined from7)A)monocytes.B)T lymphocytes.C)B lymphocytes.D)neutrophils.Answer:C8)In a complement dependent cytotoxicity assay used for HLA antigen typing, which dye can beused to identify cells that have been lysed by corresponding antibody?8)A)Ethidium bromideB)Fluorescein isothiocyanateC)Acridinium chlorideD)Carbonylmethyl fluorescein diacetateAnswer:A9)How can transplant recipients acquire HLA antibodies?9)A)Blood transfusionB)Prior organ transplantC)PregnancyD)All of the aboveAnswer:D10)Panel reactive antibody testing for preexisting HLA antibodies isnotdone on recipient's ________10)A)liver.B)progenitor (stem) cell.C)heart.D)kidney.Answer:D11)In which situation below is transplant contraindicated?11)A)Heart transplant recipient with negative T cell cross-match and positive B cell cross-matchwith donor cells.B)Kidney transplant recipient with positive T cell cross-match and negative B cell cross-matchwith donor cells.C)Liver transplant recipient with negative T cell cross-match and positive B cell cross-matchwith donor cells.D)All of the above.Answer:B12)An advantage of performing HLA cross-matches using flow cytometry is that12)A)flow cytometers are considerably less expensive than fluorescent microscopes.B)Both T and B cell cross-matches can be performed in one tube.C)the completed cross-match tubes can be stored for about a week until analysis is convenient.D)viable cells are not required.Answer:C2
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13)Observe the flow cytometry cross-match protocol in the table and interpret it. FITC is fluorosceinisothiocyanate which fluoresces green, and PE stands for phycoerythrin which fluoresces red.Tube 1Tube 2Step 1Donor cells+recipient serumDonor cells+recipient serumStep 2Incubate, washIncubate, washStep 3Add FITC-anti-IgGAdd FITC-anti-IgGStep 4Incubate, washIncubate, washStep 5Add PE-anti CD3Add PE-anti CD19Step 6Incubate, washIncubate, washStep 7flow cytometry:No fluorescence detectedflow cytometry:green & red fluorescence detected13)A)This is a positive B cell cross-match.B)This procedure must be repeated because it was performed incorrectly.C)This procedure must be repeated because no fluorescence was detected in tube 1.D)This procedure must be repeated because both fluorochromes were detected in tube 2.E)This is a positive T cell cross-match.Answer:A14)What is an important advantage of HLA testing by molecular methods?14)A)Molecular methods are inexpensive.B)Many alleles thought to be different based on serological methods have actually been shownby molecular methods to be the same.C)There is more lot-to-lot variability in antisera than there is in molecular oligonucleotideprimers.D)Although cells used for typing must still be viable, fewer cells are required to get an accuratetyping.Answer:C15)If a unrelated donor is being considered for progenitor cell transplant, which molecular HLAtyping method below is required before final transplant can occur?15)A)Low-resolution PCR sequence specific oligonucleotide primer typingB)High-resolution PCR sequence specific oligonucleotide primer typingC)Sequence-based typingD)High-resolution PCR sequence specific probe typingE)Low-resolution PCR sequence specific probe typingAnswer:C16)Which of the following isnotacceptable for specimens to be used for HLA typing?16)A)ACD anticoagulantB)Refrigerator storage up to 14 daysC)Room temperature storage up to five daysD)EDTA anticoagulantE)Heparin anticoagulantAnswer:E3
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17)When DNA has been extracted from a sample for HLA molecular typing17)A)it must be amplified immediately to insure accuracy of the process.B)it can be stored one month at–20° C.C)it can be stored in the refrigerator no more than 24 hours prior to amplification.D)it can be stored indefinitely at–70° C.Answer:D18)A high resolution HLA sequence-specific primer PCR reaction was done in a 96 well microtiterplate. Each well contains primers to a different HLA allele and the same primers to a sequence ofDNA to be used as an internal control. A negative control consists of distilled water left in an opentube during the specimen processing. After PCR, the contents of each well were electrophoresedand visualized on gel. Which finding automatically indicates a potentially invalid reaction thatrequires repeat analysis?18)A)In the well that an HLA-A gene amplified, the control sequence also amplified (i.e., twobands were visible).B)Two different alleles for the HLA-A locus were amplified.C)An allele determined by PCR does not match the allele determined by classic serology.D)No bands were visualized in the negative control.E)An allele identified by the high resolution procedure does not match the allele identified bythe low-resolution procedure.Answer:E19)Under the Clinical Laboratory Improvement Amendments (CLIA) regulations, HLA testing isconsidered19)A)low complexity.B)high complexity.C)waived.D)moderate complexity.Answer:B20)For CLIA compliance, HLA testing labs can be inspected by20)A)College of American Pathologists (CAP).B)American Association of Blood Banks (AABB).C)Centers for Medicare and Medicaid Services.D)American Society of Histocompatibility and Immunogenetics (ASHI).E)All of the above.Answer:E21)HLA labs that support transplant programs can be accredited by21)A)Centers for Medicare and Medicaid Services.B)American Society of Histocompatibility and Immunogenetics (ASHI).C)College of American Pathologists (CAP).D)American Association of Blood Banks (AABB).E)All of the aboveAnswer:B22)On-site laboratory inspection for accreditation of HLA testing laboratories must occur a minimumof every22)A)2 years.B)1 year.C)5 years.D)6 months.Answer:A4
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23)Personnel who work in HLA laboratories earn certification from the23)A)National Credentialing Agency for Laboratory Personnel.B)American Society of Clinical Pathologists.C)American Board of Histocompatibility and Immunogenetics.D)American Association of Blood Banks.E)All of the above.Answer:C24)Which process below includes all the controls utilized to make sure that a particular laboratoryanalysis is performing properly?24)A)Continuous quality improvement (CQI)B)Quality assurance (QA)C)Quality control (QC)D)Total quality management (TQM)Answer:C25)For quality control purposes, which reagent below must be tested against the antibody screeningpanel to insure that it lacks HLA antibodies?25)A)Trypan blueB)ComplementC)Protein supplementD)AntiglobulinAnswer:CSHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.26)For HLA typing, the cell of choice is the ________.26)Answer:lymphocyte27)HLA typing is acceptable on lymphocyte preparations in which>95% of the cells caningest the dye ________ ________.27)Answer:trypan blue28)The specimen required from a transplant recipient to do panel reactive HLA antibodytesting and crossmatching with donor cells is ________.28)Answer:serum29)Gels for HLA typing by PCR should be interpreted by at least ________ (how many?)people.29)Answer:230)After progenitor cell transplant, if STR DNA regions from both donor and recipient aredetected, this is called a genetic ________.30)Answer:chimeraTRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false.31)If a transplant is going to fail due to immune attack, it will be because of recipient production ofantibodies or cytotoxic T cells.31)Answer:TrueFalse32)Traditional HLA typing always requires viable cells.32)Answer:TrueFalse5
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33)A lymphocyte preparations in which<95% of the cells have ingested trypan blue must bediscarded and not used for HLA typing.33)Answer:TrueFalse34)If ethidium bromide is used as the supravital dye in a complement dependent cytotoxicity assay,then cells injured by HLA antibody will appear orange.34)Answer:TrueFalse35)An advantage of flow cytometry cross-matching is that B cells and T cells do not have to beseparated in lymphocyte preparations prior to analysis.35)Answer:TrueFalse36)Although flow cytometry donor:recipient cross-matching is not as sensitive as the traditionalcomplement dependent cytotoxicity assays, it is widely used because it is automated andsignificantly reduces turnaround time.36)Answer:TrueFalse37)When DNA is extracted from a sample for HLA typing, the purity of the sample is best determinedby the ratio of the sample's absorbance at 260 and 280 nm.37)Answer:TrueFalse38)PCR sequence specific oligonucleotide probe methods are usually preferred for large volumes ofspecimens over PCR sequence specific primer methods.38)Answer:TrueFalse39)It is still normal a year after progenitor cell transplant to perform STR analysis and find both donorand recipient DNA in peripheral blood white cells.39)Answer:TrueFalse40)One of the most frequent reasons for death after a progenitor cell transplant is graft versus hostdisease.40)Answer:TrueFalseSHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.41)List three ways that T and B cells can be separated from each other using mononuclear cellpreparations.41)Answer:1. T cells possess the CD2 receptor that binds to sheep RBCs. When sheep RBCs areadded to a mononuclear preparation, T cells will bind to them, and the heavier cellclusters can be removed from B cells by Ficoll-Hypaque density gradients. Lysis of thesheep RBCs liberates the T cells.2. Aliquots can be mixed with magnetic particles coated with monoclonal antibodies to Tand B cells. For example, when anti–T cell particles are added, T cells bind to the particlesand are held to the side of the test tube with a magnet while B cells are decanted off.3. Nylon wool non-specifically bind B cells and monocytes, allowing T cells to bewashed through and collected. A cold wash then removes B cells.6
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42)List the steps in a complement dependent cytotoxicity assay used for HLA antigen typing.42)Answer:A complement dependent cytotoxicity assay proceeds as follows:1. Aliquots of cells are mixed with different HLA antibodies and incubated.2. Complement is added.3. Supravital dye is added. Injured cells cannot exclude ethidium bromide and will beorange while intact cells are capable of retaining carbonylmethyl fluorescein diacetate andappear green.4. Formalin is added to fix cells.5. Lysis is determined by the presence of dye in cells.43)How can the sensitivity of the cross-match between the recipient's serum and the donor'scells be enhanced?43)Answer:After the initial serum:cell incubation in a cross-match, the cells can be washed(Amos modification) to remove any unbound antibodies that have fixedcomplement. Antihuman globulin can then be added to enlarge any formedimmune complexes. Fresh complement is then added, and the larger immunecomplexes should activate it efficiently. Detection of Class I antibodies in thepresence of Class II antibodies can be enhanced by first absorbing the recipient'sserum with donor platelets that express Class I but not Class II antigens.44)Describe the technique of the mixed lymphocyte culture reaction (MLC).44)Answer:When live lymphocytes recognize foreign Class II HLA antigen on other cells, theystimulate proliferation of several white cell lines to destroy the foreign cells. For anMLC, two mononuclear cell populations are prepared, one from the transplantrecipient and one from the donor. The cells from the donor are treated with aninhibitor of DNA synthesis, so that while they might stimulate a reaction from therecipient's cells, they are not capable of mounting their own response to therecipient's cells. The two cell preparations are mixed in a culture medium thatcontains tritiated thymidine. If the recipient's cells do not recognize any HLAantigens in the donor's cells as foreign, no proliferation occurs, and the cells do nottake up the tritiated thymidine to any significant degree. If the recipient's cells dorecognize any HLA antigens in the donor's cells as foreign, proliferation occurs andthe cells take up the tritiated thymidine aggressively.45)What is a short tandem repeat (STR), and how can it be used to determine progenitor cellengraftment?45)Answer:Throughout each chromosome are areas of repeated sequences that are nottranslated as part of any known gene. Variable number tandem repeats (VNTRs) arerepeats of 9–80 base pairs while short tandem repeats (STRs) are repeats of 2–7 basepairs. Since the repeated sequences are not translated, mutations in these areas arehighly tolerated, leading to substantial differences between individuals regardingthe actual number of base pairs repeated in each of these regions. These differencescan be used as markers to identify the individual who is the source of a piece ofDNA. Prior to progenitor cell transplant, the STR regions of donor and recipientDNA are tested until an "informative locus" is found. An informative locus is one inwhich the donor and recipient STRs differ enough that their DNA can bedifferentiated. Several loci typically need testing as progenitor cell transplants areoften done with related donors. Once an appropriate locus is determined, STRanalysis of white cell DNA in the recipient can be done to determine the degree towhich the donor's cells did or did not successfully engraft.7
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ExamName___________________________________MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.1)The most primitive component of the immune response found even in some of the simplest formsof life is the ability to1)A)distinguish self from non-self.B)produce phagocytes.C)mount a cellular immune response.D)produce antibodies.Answer:A2)Immunology was originally a subdiscipline of2)A)blood banking.B)transplantation.C)anatomic pathology.D)microbiology.Answer:D3)Which of the following is (are) characteristics of nonspecific, innate immunity?3)A)Only needs to recognize agent as "non-self" to react.B)Responds to all challenges equally.C)Has no "memory." It does not react differently when reexposed to the same agent.D)Reacts without prior exposure to the agent.E)All of the above.Answer:E4)A child has chicken pox and recovers. Later, she is exposed to chicken pox and does not get sick,but when she is exposed to influenza she does get sick. This is an example of4)A)innate immunity.B)vaccination.C)nonspecific immunity.D)adaptive immunity.Answer:D5)A man opens up an old loaf of bread and inhalesPenicilliumspores from the organism growinginside. Inside the man's lungs, phagocytes engulf and digest the spores. The man never gets sick.This is an example of5)A)vaccination.B)adaptive immunity.C)specific immunity.D)variolation.E)innate immunity.Answer:E6)The definition of antigen is6)A)the portion of the antibody that binds to the microorganism.B)an infectious, pathogenic microorganism.C)the portion of the white blood cell responsible for recognizing something as "non-self."D)the exact portion of a microorganism or chemical that the immune system reacts against.Answer:D1
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7)In the recognition phase of the immune response, the body must determine that7)A)a microorganism is different that what is usually present in the normal flora.B)the antigen encountered is "non-self."C)a substance is capable of causing harm.D)a microorganism is capable of causing actual disease.Answer:B8)The first description of inflammation came from ancient Rome and included all the componentslisted belowexcept8)A)swelling.B)pain.C)pus.D)heat.E)redness.Answer:C9)In humans, after the recognition phase of the immune reaction, the response phase consists of9)A)activation of the adaptive, specific immune components.B)activation of the innate, nonspecific immune components.C)both A and B.D)Cannot tell from this information. It depends on the immunizing agent as to whether A or B isused.Answer:C10)The English physician who vaccinated a boy with cowpox to induce immunity to smallpox was10)A)Robert Koch.B)Peter Medawar.C)Louis Pasteur.D)Edward Jenner.E)Celsus Galen.Answer:D11)Simian immunodeficiency virus (SIV) causes a disease in monkeys similar to AIDS in humanscaused by human immunodeficiency virus (HIV). In theory, why would SIV be a candidateorganism to be used in a human AIDS vaccine?11)A)SIV could stimulate a humoral immune response against HIV.B)SIV could stimulate a cellular immune reaction against HIV.C)Monkey viruses cause disease in humans.D)Monkey viruses cannot cause disease in humans.E)SIV could stimulate an immune response against SIV that cross-reacts with HIV.Answer:E12)The person who won the Nobel prize in 1908 for his work in demonstrating phagocytosis by whiteblood cells is12)A)Paul Erlich.B)Elie Metchnikoff.C)Edward Jenner.D)Robert Koch.E)Louis Pasteur.Answer:B2
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13)The first true vaccine given to a human containing the specific pathogen to which immunity wasdesired was13)A)chicken fowl cholera.B)anthrax.C)tetanus.D)rabies.E)diphtheria.Answer:D14)The first research identifying the activity of antibodies demonstrated that14)A)the immunity could be transferred from one animal to another using the serum component ofblood.B)the immunity was produced by B lymphocytes.C)the immunity could be transferred from one animal to another using the cellular componentof blood.D)the immunity was produced by T lymphocytes.Answer:A15)Hyperacute rejection of a solid organ transplant occurs if there is a mismatch of15)A)HLA types.B)MHC types.C)ABO blood types.D)tissue types.Answer:C16)The first successful human kidney transplant was in 1954. Why was it successful?16)A)The recipient and the donor had identical tissue types.B)The recipient and the donor were identical twins.C)The recipient and the donor had identical ABO blood groups.D)All of the above.Answer:D17)How were the cells responsible for cell-mediated immunity first identified as T lymphocytes?17)A)Metchnikoff demonstrated phagocytosis of fungal spores byDaphniablood cells.B)Ehrlich demonstrated it using cells isolated from the Bursa of Fabricius in chickens.C)Glick demonstrated it using cells isolated from chicken thymus.D)Landsteiner demonstrated it showing incompatibility between sera of people with differentblood groups.Answer:C18)In early studies of antibodies, which properties were recognized?18)A)Ability to cause precipitation reactions.B)Ability to agglutinate particles.C)Antitoxin effects.D)All of the above.Answer:D3
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19)The selective/clonal selection theory of immune response ultimately proved to be correct, but theinstructional theory, while incorrect, seemed logical because19)A)if thousands of preformed antibodies were present to antigens that are never encountered,this is excessively wasteful and poor use of the body's resources.B)the immune system was shown to be capable of such a wide variety of substances that itseemed impossible that such a high number of different possibilities would be preformedwithout any prior exposure.C)if one gene produces one antibody, then it didn't seem that humans had enough DNA toproduce thousands of possible antibodies.D)it seemed reasonable that a cell would be "instructed" to react to a specific antigen only whenit was encountered.E)All of the above.Answer:E20)Which breakthrough below is mostly responsible for supporting the clonal selection theory of theimmune response?20)A)Discovery of the T cell receptorB)Discovery of the genes encoding for different portions of antibody moleculeC)Discovery of how monoclonal antibodies can be produced artificiallyD)Discovery of the chain structure of antibodiesAnswer:B21)What is a monoclonal antibody?21)A)An antibody produced by a mature, stimulated B cell.B)An antibody produced in response to an antigen with a repeating epitope.C)An antibody produced by a hybridoma cell.D)An antibody produced in response to an antigen with only one epitope.E)An antibody produced by an immature B cell.Answer:C22)How can hybridoma cells be kept alive for extended periods of time? (Check as many as apply.)22)A)They can't. Once removed from the host animal the cells die quickly.B)Growing them at refrigerator temperature.C)Placing them into a susceptible host where they will form a tumor.D)Using the appropriate cell culture techniques.E)Growing them in a field of ionizing radiation.Answer:C, D23)Which of the cell types listed below needs to have antigen processed before it can be recognized?23)A)B lymphocytesB)NeutrophilsC)T lymphocytesD)EosinophilsE)Monocytes/macrophagesAnswer:C4
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24)Which of the following istrueregarding immunoglobulins?24)A)Immunoglobulins exist preformed on the surface of B lymphocytes.B)They are the major mediator of specific humoral immunity.C)Immunoglobulins are also called antibodies.D)All of the above.Answer:D25)T lymphocytes recognized foreign antigen and discriminate self from non-self using25)A)the MHC complex.B)the T cell antigen receptor.C)ABO antigens.D)A and B.E)A and C.Answer:DSHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.26)________ are responsible for cell-mediated immunity while ________ are responsible forhumoral immunity.26)Answer:T lymphocytes/B lymphocytes or antibodies27)The study of organ transplantation was vastly improved when the cause of different tissuetypes, the ________, was discovered by Snell, Dausett, and Benacerraf.27)Answer:major histocompatibility complex28)The person who discovered the ABO human blood groups is ________.28)Answer:Karl Landsteiner.29)Rejection of transplanted organs can be minimized if ________ testing is done to assesstissue compatibility between donors and recipients.29)Answer:HLA or histocompatibility testing30)________ is when one's own tissues are attacked by one's own immune system.30)Answer:AutoimmunityTRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false.31)The human immune system never responds against human tissues.31)Answer:TrueFalse32)The adaptive arm of the immune system is capable of memory.32)Answer:TrueFalse33)In terms of organism survival, cellular immunity is more important than humoral immunity.33)Answer:TrueFalse34)Antibodies can only be formed against microorganisms or products they produce, such as toxins.34)Answer:TrueFalse5
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35)When serum is divided into fractions by an electrical field, antibodies migrate in the beta fraction.35)Answer:TrueFalse36)It is believed that the phagocytic cells observed by Metchnikoff were macrophages andpolymorphonuclear neutrophils.36)Answer:TrueFalse37)Louis Pasteur accidentally discovered vaccination using attenuated microorganisms by injecting anold bacterial culture into chickens.37)Answer:TrueFalse38)Paul Erlich was the first to propose that white blood cells had some structure that could bind toantigens similar to a "lock and key."38)Answer:TrueFalse39)B lymphocytes can react against unprocessed antigen.39)Answer:TrueFalse40)T cells recognize antigens by virtue their corresponding receptors on their cell surfaces.40)Answer:TrueFalseSHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.41)What was variolation?41)Answer:Variolation was a crude vaccination attempt in which crusts from smallpox scabswere introduced into skin scratches or inhaled to try to induce immunity tosmallpox. Although it worked in some cases, it was dangerous because if excessive,live smallpox virus was introduced, disease resulted.42)Explain why Jenner was successful in making a boy immune from smallpox by vaccinatinghim with cowpox.42)Answer:Cowpox is a milder disease than smallpox, but it still induces T cell response(cellular immunity) and B cell response (antibodies). The two viruses contain somesimilar antigens such that the specific immune response against cowpox cross-reactswith smallpox antigens and gives the host immunity to small pox.43)Define attenuation and explain why attenuated organisms are useful for vaccines.43)Answer:An organism that is old or otherwise weakened such that it cannot cause disease issaid to be attenuated. It should still possess many or most of its antigens that couldinitiate an immune reaction. Therefore, if the weakened organism were injected intoa host, the immune reaction should be specific against the appropriate antigens butthe host should not get sick.6
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44)Briefly outline the clonal selection theory of adaptive immunity.44)Answer:Immature uncommitted lymphocytes have the genetic material to respond to a largevariety of antigens. During the maturation process, lymphocytes differentiate andbecome committed to a particular antigen. At all times, there are a small number ofmature lymphocytes developed that are capable of responding to every possibleantigen that the host can genetically react against. When a particular antigen isencountered, the lymphocyte clone(s) capable of responding to that particularantigen is (are) "selected" or stimulated by the antigen to multiply rapidly andactivate an immune response.45)Explain what a hybridoma cell is and what it does.45)Answer:A hybridoma cell is a fusion of a malignant myeloma cell and an immunizedlymphocyte. The malignant nature of the myeloma cell confers upon the hybridomaalmost limitless life in cell culture, while the immunized lymphocyte confers theability to produce an antibody of a particular type. The hybridoma cell, therefore,produces only one antibody type (monoclonal) in massive amounts artificially incell culture.7
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ExamName___________________________________MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.1)How does normal microbial flora on the human body prevent infection?1)A)Its presence stimulates lysozyme secretions.B)Its presence stimulates acute phase reaction proteins.C)Its secretions maintain a low pH inhibitory to most pathogens.D)Its presence reduces nutrients and space needed for pathogens to grow.E)All of the above.Answer:D2)Each chemical below is pairedcorrectlywith its antimicrobial effectexcept2)A)interferon/activation of cellular immunity and inhibition of viral replication.B)lactoferrin/binds complex carbohydrates (like lactose) so that organism can't utilize it.C)fibronectin/when bound to bacterial cells walls, promotes phagocytosis.D)transferrin/binds iron so that organisms can't utilize it.E)lysozyme/degrades bacterial cell walls.Answer:B3)The granules in mature neutrophils contain all of the followingexcept3)A)transferrin.B)alkaline phosphatase.C)lysozyme.D)gelatinase.E)histamine.Answer:E4)The process by which neutrophils leave blood vessels, squeezing between the endothelial cells toenter the tissues, is called4)A)phagocytosis.B)margination.C)chemotaxis.D)diapedesis.E)opsonization.Answer:D5)A clinical laboratory scientist observed a peripheral blood smear and noticed one to two pale blueinclusions in several neutrophils. Which of the following would be consistent with thisobservation?5)A)C-reactive protein is increased.B)Several neutrophils also have vacuoles.C)Serum albumin and transferrin are decreased.D)The total white blood cell count is high with an absolute neutrophilia.E)All of the above.Answer:E1
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