Immunology Practice Questions_MCQ
Which of the following are true? IgE is 1. An allergy associated immunoglobulin 2. the least abundant immunoglobulin in the plasma 3. binds to mast cells 4. can cross the placental barrier
1. An allergy associated immunoglobulin 2. the least abundant immunoglobulin in the plasma 3. binds to mast cells
Which of the following are true? IgE is 1. An immunoglobulin associated with some kinds of allergic reactions 2. the least abundant typo at antibody synthesized 3. associated with tle mast cell for histamine release 4. produced during the primary immune response before class switching
1. An immunoglobulin associated with some kinds of allergic reactions 2. the least abundant typo at antibody synthesized 3. associated with tle mast cell for histamine release
Which of the following are true statements 1. IgM and IgG can fix complement 2. IgA is a secretory immunoglobulin 3. IgE mediates immediate hypersensitivity 4. IgD provides most passively acquired maternal immunity
1. IgM and IgG can fix complement 2. IgA is a secretory immunoglobulin 3. IgE mediates immediate hypersensitivity
Which of the following are true? A critical property of an antigen is 1. Its ability to stimulate an immune response 2. a unique topotogical feature called an paratope 3. a unique topological feature called an epitope 4. not a unique topological feature called an antigenic determinant
1. Its ability to stimulate an immune response 3. a unique topological feature called an epitope
Class II MHC proteins are 1. Recognized by the T4 (or CD4) protein 2. used to mark a cell for killing by cytotoxic T-cells 3. used to participate in helper function 4. not able to carry an antigen fragment
1. Recognized by the T4 (or CD4) protein 3. used to participate in helper function
Which of the following are true? An antigenic determinant is 1. a small topological feature of a large macromolecule such as A protein or carbohydrate 2. specifically recognized by a epitope 3. specifically recognized by a paratope 4. specifically recognized by the T4 protein
1. a small topological feature of a large macromolecule such as A protein or carbohydrate 3. specifically recognized by a paratope
The basic monomeric immunoglobulin unit is 1. composed of four polypeptides chains 2. representative of a single protein type for all antibody classes 3. able to associate with J- chain to form multimers in some cases 4. the same structure as the T-cell antigen receptor
1. composed of four polypeptides chains 2. representative of a single protein type for all antibody classes 3. able to associate with J- chain to form multimers in some cases
Which of the following are true? The basic monomeric Immunoglobulin unit is 1. composed of four; polypeptide chains 2. only an integral membrane protein and never secreted 3. one of five major classes 4. synthesized by a T-cell without carbohydrate
1. composed of four; polypeptide chains 2. only an integral membrane protein and never secreted 3. one of five major classes
The basic monomeric form of an immunoglobulin 1. is a tetramer consisting of two light and two heavy chains 2. is associated with J-chain in the IgD 3. can occur as multimers with IgA and IgM 4. exists only on the cell surface of B-cells
1. is a tetramer consisting of two light and two heavy chains 2. is associated with J-chain in the IgD 3. can occur as multimers with IgA and IgM
Which of the following are true? Complement fixation 1. can be modified by the Cholera toxin 2. has intrinsic Guanylate cyclase activity 3. can be desensitized by phosphorylation 4. is an effector function of IgG and IgM following antigen binding
2. has intrinsic Guanylate cyclase activity 4. is an effector function of IgG and IgM following antigen binding
Which of the following are true? IgE 1. is produced by mast cells 2. is produced by B-cells 3. is produced by T-cells 4. binds to mast cells
2. is produced by B-cells 4. binds to mast cells
Which of the following are true? The antigenic determinate 1. is the combining site of an antibody 2. is usually no more than five or six amino acids of the antigen 3. is the paratope 4. Consists of a small topological feature of the antigen
2. is usually no more than five or six amino acids of the antigen 4. Consists of a small topological feature of the antigen
Antibodies 1. are carbohydrates 2. are made from alpha and beta chains 3. contain no carbohydrate 4. contain heavy and light chains
4. contain heavy and light chains
A precocious kindergarten child, decided to take her three week old baby brother out of the carriage so that she could play "mother". Unfortunately she tripped, and the baby fell onto an old tin can which the dog had dragged onto the front lawn. Since the baby received a laceration, the mother rushed him to the doctor. Which of the following would be the preferred treatment? A. A tetanus immune globulin (human) injection this visit, with an injection of tetanus toxoid several weeks later. B. A mixture of tetanus toxoid and tetanus immune globulin (human) as one injection. C. A tetanus immune globulin (human) infection this visit, with an injection of tetanus toxiod the following week. D. Separate injections of tetanus toxoid and tetanus immune globulin in different sites on this one visit. E. A tetanus toxoid injection this visit, with an injection of tetanus immune globulin (human) approximately one week later.
A. A tetanus immune globulin (human) injection this visit, with an injection of tetanus toxoid several weeks later.
A two-year-old boy presents with recurrent bacterial infections. On physical examination the physician notes that the person has no lymph nodes, and no tonsils. The laboratory tests indicate that there are virtually no circulating B cells. The person's cell mediated immunity, as tested in vivo by skin reactivity, is normal. A. Bruton's agammaglobulinemia. B. Hyper IgM syndrome C. Selective IgA deficiency. D. Chronic granulomatous disease
A. Bruton's agammaglobulinemia.
Three- year-old Johnny gets burned in a home accident and requires extensive skin grafting. The attending physician believes that Johnny will tolerate the graft with little, (or no) immunosuppressive drugs since the child has an immunodeficiency disorder. Johnny most likely has: A. DiGeorge's Syndrome B. Chronic Mucocutaneous Candidiasis C. X-linked Agammaglobulinemia D. Chediak-Higashi Syndrome E. Chronic Granulomatous Disease
A. DiGeorge's Syndrome
Which of the following immunoglobulins is present normally in plasma at the highest concentration? A. IgG B. IgM C. IgA D. IgD E. IgE
A. IgG
In the developmental pathway of B lymphocytes, the sequence of events is as follows: A. Rearrangement of heavy chain, rearrangement of light chain, surface IgM, surface IgD. B. Rearrangement of light chain, rearrangement of the heavy chain, surface IgM, surface IgD. C. Rearrangement of light chain, rearrangement of the heavy chain, surface IgD, surface IgM. D. Rearrangement of heavy chain, surface IgM, rearrangement of the light chain, surface IgD. E. Rearrangement of heavy chain, rearrangement of the light chain, surface IgD, surface IgM.
A. Rearrangement of heavy chain, rearrangement of light chain, surface IgM, surface IgD.
A 21-year-old female presents with a three week history of symmetrical swelling of the small joints of the hands and feet and morning stiffness of one and one-half hour duration. Tests indicate IgM auto-antibodies that have a specificity for Fc portion of IgG. This patient most likely has: A. Rheumatoid Arthritis B. Goodpasture's Syndrome C. Type 1 diabetes D. Graves' Disease E. Myasthenia Gravis
A. Rheumatoid Arthritis
Baby Y was born with high titers of deoxy-ATP anddeoxyadenosine. He has also shown an increased susceptibility to both intracellular (i.e. viruses) and extracellular (i.e. bacteria) pathogens. What do you suspect? A. SCID B. XLA C. CGD D. Chediak higashi syndrome
A. SCID
Which of the following uniquely distinguishes the T-cell receptor (TCR) from an antibody? A. The TCR can bind an antigen fragment only in a trimolecular complex with either the class I or class II surface proteins of the major histocompatibility complex B. The TCR can function as a cell surface antigen receptor C. The TCR is composed of two different types of polypeptide chains D. The TCR is capable of participating in a cytotoxic reaction. E. The TCR polypeptides is composed of domains - an amino terminal variable portion at determines the binding specificity and a constant portion that determines the class of the polypeptide chain.
A. The TCR can bind an antigen fragment only in a trimolecular complex with either the class I or class II surface proteins of the major histocompatibility complex
An individual's finger was caught in a car door and as a result sustained significant tissue damage and internal bleeding without breaking the skin or infecting the wound with foreign material. Which of the following is the MOST likely explanation for the resulting inflammation? A. The inflammation must be the result of nonimmunologic mechanisms because there are no foreign antigens present. B. The inflammation must be attributable to natural killer (NK) cells because they do not have a unique antigen receptor. C. The inflammation is related to an increase in the amount of C4bC2a on the surface of the damaged tissue. D. The inflammation is related to an increased constitutive production of C3b by clotting factors
A. The inflammation must be the result of nonimmunologic mechanisms because there are no foreign antigens present.
Class switching of immunoglobulins occurs A. Usually with booster immunizations, going from IgM to IgG B. binds complement C. causes the histamine release D. mediates immunoglobulin class switching E. results in the glycosylation of immunoglobulins
A. Usually with booster immunizations, going from IgM to IgG
The major role of the complement system is to work in conjunction with A. antibodies to lyse cells via the C8 and C9 components B. the major histocompatibility complex for cell recognition C. antibodies to opsonize cells D. the T-cell receptor for production of lymphokines E. antibodies to lyse cells via the perforin molecules
A. antibodies to lyse cells via the C8 and C9 components
The T3 complex of the T-cell receptor A. probably functions to transduce a signal to the cell's interior following binding of complexed antigen B. binds complement C. causes the histamine D. mediates Immunoglobulin class switching E. results in the glycosylation of jmmunoglobuiins
A. probably functions to transduce a signal to the cell's interior following binding of complexed antigen
51. A child disturbs a wasp nest, is stung repeatedly, and goes into shock within minutes, manifesting respiratory failure and vascular collapse. This is MOST likely to be due to: A. systemic anaphylaxis B. serum sickness C. an arthus reaction D. cytotoxic hypersensitivity
A. systemic anaphylaxis
Cytokines are produced by cells of the immune system in response to various physiological stimuli A. modulate cell function through subsequent cell differentiation or cell proliferation B. facilitate cell lysis C. cause glycosylation of Immunoglobins D. cause histamine release E. facilitate perforin release
All
Which of the following are true? Antibodies are 1. Immunoglobulins 2. composed of variable and constant region domains 3. made of heavy and light chains 4. glycoproteins
All
Which of the following are true? Immunoglobins 1. are antibodies 2. are classified into five major classes, i.e., IgM, IgG, IgA, IgD, IgE 3. have a molecular specificity to recognize unique epitope 4. possess both variable and constant region domains
All
B-cell lymphomas in mice, when experimentally treated with anti-idiotype sera, show regression. However, they frequently recur and now show no reactivity with the same anti-idiotype sera. Likely explanation(s) for this change could be: A. Production of Ig splitting enzymes by the lymphoma cells. B. A loss of surface Ig receptor on the B-lymphoma cells. C. Production of anticomplementary substances by the lymphoma cells. D. A change in idiotype expressed by CD4+ T cell receptor.
B. A loss of surface Ig receptor on the B-lymphoma cells.
A young boy has had repeated infections with Staphylococcus aureus. His laboratory data reveals that he has normal numbers of white blood cells with a normal distribution by differential counting. His immunoglobulin levels are normal and he responds to candida skin test antigen with a positive DTH reaction. Which of the following types of immune deficiency do you suspect? A. B cell deficiency B. Granulocyte disorder C. Combined immunodeficiency D. T cell deficiency
B. Granulocyte disorder
Which statement is UNTRUE? A. Hyperacute rejection occurs in minutes to hours. B. Hyperacute rejection is readily treated with immunosuppressive drugs. C. Hyperacute rejection is associated with early thrombosis and endothelial injury. D. Hyperacute rejection is caused by preformed antibodies.
B. Hyperacute rejection is readily treated with immunosuppressive drugs.
A 3-year-old boy has a history of repeated pyogenic (pus-forming) infections. He had normal antibody responses following childhood immunizations and normal recovery from chickenpox and measles. Decreased numbers or functional defects in which of the following cells best explains the cause of his infections? A. Eosinophils B. Neutrophils C. T lymphocytes D. B lymphocytes
B. Neutrophils
6. You are running a tissue typing laboratory and are faced with matching a potential kidney transplant recipient with one of several unrelated donors. Serology indicates 5/6 MHC matches. Which of the following would be the MOST judicious course of action? A. Proceed with transplantation, with no immunosuppression. B. Proceed with transplantation, using cyclosporin and prednisone. C. Wait until you get 6/6 MHC matches. D. Wait further matching data from MLR (72 hrs).
B. Proceed with transplantation, using cyclosporin and prednisone.
T-cell antigen receptors are distinguished from antibodies by which of the following A. T-Cell receptors are glycosylated B. T-cell receptors must interact with antigen uniquely presented by other cells but not with free antigen C. T-Cell receptors bind various cytokines D. T-Cell receptors bind complement to lyse cells E. T-cell receptors are mediators of allergic reactions
B. T-cell receptors must interact with antigen uniquely presented by other cells but not with free antigen
. A patient with a central nervous system disorder is maintained on the drug methyldopa. Hemolytic anemia develops, which resolves shortly after the drug is withdrawn. This is MOST probably an example of: A. Type I hypesensitivity B. Type II hypersensitivity C. Type III hypersensitivity D. Type IV hypersensitivity
B. Type II hypersensitivity
26. An antibody directed against the idiotypic determinants of a human IgG antibody would react with: A. the Fc part of the IgG. B. an IgM antibody produced by the same plasma cell that produced the IgG. C. all human kappa chains D. all human gamma chains
B. an IgM antibody produced by the same plasma cell that produced the IgG.
T-cell receptors or antibodies react with antigens A. because both are made by lymphocytes B. because of complementary of molecular fit of both with antigen C. because both 'have light chain and heavy chain polypeptides D. cause histamine release E. facilitate perforin release
B. because of complementary of molecular fit of both with antigen
39. A 7-month-old girl has a history of severe recurrent bacterial and fungal infections. Analysis of serum Igs, B and T cell counts (and function) show no clear abnormality. Which one of the following should you suspect? A. multiple myeloma B. chronic granulomatous disease C. X-linked agammaglobulinemia D. selective IgA deficiency E. severe combined immunodeficiency disease
B. chronic granulomatous disease
After bone marrow transplant from his HLA matched sister, Jimmy developed a syndrome characterized by pancytopenia , aplastic anemia, skin rash, diarrhea, jaundice and weight loss. This condition is called: A. allograft rejection. B. graft versus host disease. C. failure of bone marrow engraftment. D. a secondary infection. E. anamnesis.
B. graft versus host disease.
21. You prescribe penicillin for your patient. The patient develops a severe allergic reaction and dies. In this case, the penicillin molecule was probably acting as a (an): A. adjuvant. B. hapten. C. immunologic carrier. D. immunotoxin
B. hapten.
27. "Isotype switching" of immunoglobulin classes by B cells involves: A. simultaneous insertion of VH genes adjacent to each CH gene. B. insertion of a single VH gene adjacent to different CH gene. C. activation of homologous genes on chromosome 6. D. switching of light-chain types (kappa and lambda)
B. insertion of a single VH gene adjacent to different CH gene.
By the age of 9-months, Baby M had had several episodes of sinusitis and otitis media. Recent tests revealed that this child cannot form antibodies to bacterial antigens. Further tests indicate that the "machinery" for making antibodies is intact, but has not yet matured to yield expression of antibodies. Hence a replacement therapy with IgG was started. This therapy: A. will cure infections of Lymphocytic Choriomeningitis Virus. B. may delay the formation of his/her own antibodies. C. may form immune complexes that activates B cells. D. will cure Leishmania infections.
B. may delay the formation of his/her own antibodies.
Light chains are A. specific for each class of antibody B. not specific for each class of antibody C. reactive with antigen D. have only a constant region E. are composed only of carbohydrate
B. not specific for each class of antibody
A 17-year-old boy suffered an injury to his left eye when, during a car crash, a sharp silver of glass penetrated his eye, damaging his lens and uveal tract. The glass was removed and the injury repaired with complete recovery. However, 3 weeks later he noticed some redness in the left eye and photophobia, followed by pain and severe visual impairment. The left eye was removed and histologic examination showed an extensively infiltrated uveal tract with abundant lymphocutes and mononuclear cells. Two weeks later the other eye began to show the same symptoms. Since the lens was damaged the most likely scenario is that: A. this is an example of immediate hypersensitivity. B. sequestered antigen was released and initiated an immune response. C. some of the glass must have penetrated the right eye as well. D. the bacteria entered the damaged eye and is causing an infection in both eyes.
B. sequestered antigen was released and initiated an immune response.
A 42-year-old female had a renal transplant. She was treated with cyclosporine and steroids. However, two weeks post transplantation she presented with deteriorating renal function. Her dose of immunosuppressive therapy was increased and she responded favorably. Which of the following syndromes did she have? A. Hyperacute rejection B. Chronic rejection C. Acute rejection D. All of the above E. Only b + c
C. Acute rejection
You are a cardiologist and are asked to see a 28-year-old female patient in regards to palpitations and hyperactivity. Her GP tells her she is merely "overanxious", but she is afraid she is having intermittent symptoms of a heart attack! When you see her you are struck by her thick neck and marked protuberance of the eyes (exophthalmos). TSH levels are low. Cariological work-up is normal. Which one of the following tests might you perform to elucidate the basic mechanism that underlies the patient's symptoms? A. Biopsy of tissue in the neck. B. Assay immunoglobulin and/or complement activity. C. Assay for antibody to TSH-receptor. D. Assay for anti-thyroxin antibody.
C. Assay for antibody to TSH-receptor.
One principal function of complement is to A. inactivate perforins B. mediate the release of histamine C. Bind antibodies attached to cell surfaces and to lyse these cells D. phagocytize antigens E. cross link allergens
C. Bind antibodies attached to cell surfaces and to lyse these cells
You have a patient who makes autoantibodies against his own red blood cells, leading to hemolysis. Which one of the following mechanisms is MOST likely to explain the hemolysis? A. Neutrophils release proteases that lyse the red cells. B. Perforins from cytotoxic T cells lyse the red cells. C. Complement is activated, and membrane attack complexes lyse the red cells. D. Interleukin-2 binds to its receptor on the red cells, which results in lysis of the red cells.
C. Complement is activated, and membrane attack complexes lyse the red cells.
A patient who is allergic to ragweed developed IgE myeloma (plasma cell that secretes IgE). The myeloma IgE does not react with the ragweed pollen. What would be the effect of his myeloma on the severity of his allergic symptoms during hayfever season? A. Increased due to his having more IgE. B. No change C. Decrease due to the displacement of IgE anti-ragweed on mast cell by myeloma IgE. D. Increase due to the blocking effect of the myeloma.
C. Decrease due to the displacement of IgE anti-ragweed on mast cell by myeloma IgE.
Which one of the following substances works to directly reverse bronchoconstriction and hence is the treatment of choice in severe allergic respiratory distress? (NOTE: ONLY FOUR CHOICES) A. Cromolyn sodium B. Antihistamines C. Epinephrine D. Blocking antibody
C. Epinephrine
A 57-year-old female complains of cold intolerance and undue fatigue. Her hemoglobin is 13-gm/dl (normal 12-14). Tests indicate auto-antibodies to thyroglobulin, and to microsomal antigens from thyroid epithelial cells. This patient most likely has: A. Rheumatoid Arthritis B. Goodpasture's Syndrome C. Hashimoto's Thyroiditis D. Systemic Lupus Erythematosus E. Graves' Disease
C. Hashimoto's Thyroiditis
Which immunoglobulin is the principal one found in secretions such as milk? A. IgG B. IgM C. IgA D. IgD E. IgE
C. IgA
An Rh-negative mother had an anti-Rh response following the birth of her Rh-positive child. The second fetus was also Rh+ so the maternal anti-Rh antibodies coated the fetus's erythrocytes with antibody. The isotype of these antibodies is A. IgA B. IgD C. IgG D. IgE E. IgM
C. IgG
42. Gm allotypes in the population refer to allotypic differences in which antibody isotype? A. IgM and IgD B. IgA and IgM C. IgG and IgA D. IgE and IgM
C. IgG and IgA
A woman comes into your office complaining of lesions on her legs. The lesion is a plaque with irregular raised, indurated brown areas. In all other respects she is asymptomatic. You decide to run a serological test. The presence of which antigen would you expect to find? A. 17-1A B. Galectin 9 C. Mage 1-3 D. mIg
C. Mage 1-3
A positive DTH skin reaction involves the interaction of: A. antigen, complement, and lymphokines. B. antigen-antibody complexes, complement and neutrophils. C. Memory T cells, cytokines and macrophages. D. IgE antibody, antigen, and mast cells E. Antigen, macrophages and complement.
C. Memory T cells, cytokines and macrophages.
Mr. Arnold was mowing in his back yard when a bee stung him. He has a known allergy to bee venom, having been stung twice before. He immediately went inside and gave himself an injection with his Epinephrine pen. This saved his life. Which one of the following is true? A. Antigen exposure induced IgG production such that IgG bound to to FcR on mast cells. B. Mr. Arnold did not have any pre-existing antibodies to bee venom. C. Mr. Arnold has previously been sensitized and has IgE antibodies specific for bee venom. D. Immune complexes formed in excess deposit on capillary walls during the effector phase of this reaction type.
C. Mr. Arnold has previously been sensitized and has IgE antibodies specific for bee venom.
You see a young man in the later stages of HIV infection with a markedly decreased CD4+ T-cell count, diarrhea and weight loss, fever and oral candidiasis. Which one of the following is NOT necessarily an anticipated infection in this man? A. Intestinal and pulmonary cytomegalovirus infection. B. Systemic herpes virus infection. C. Pneumococcal pneumonia. D. Fungal infection
C. Pneumococcal pneumonia.
A 27-year-old housewife presents to her family physician with a 3 month history of fatigue, and a facial rash which is aggravated by sun exposure. Laboratory tests reveal anemia of 10-gm/dl (normal is 12-14) and immune testing reveals auto-antibodies against DNA. What is the most likely diagnosis? A. Rheumatoid Arthritis B. Goodpasture's Syndrome C. Systemic Lupus Erythematous D. Graves Disease E. Myasthenia Gravis
C. Systemic Lupus Erythematous
All of the following are true with respect to IgE molecules, EXCEPT which one? A. They are the principal immunoglobulin class involved in allergic reactions. B. They are involved in mediating anti-parasitic immune responses. C. They will cross the placenta and fix complement. D. They can effect the release of histamine and other chemical mediators. E. They are the least abundant immunoglobulin in the serum.
C. They will cross the placenta and fix complement.
Immune surveillance should provide the mechanism for the elimination of tumors that express tumor specific antigens. However, the presence of tumors in patients indicate that there are factors that enable the tumor to escape the immune system, as listed below. Which one of the following is INCORRECT? A. Tumors may be in privileged sites. B. Tumors may change their surface antigens (antigenic modulation). C. Tumor antigens may be recognized by T-cells in the absence of MHC. D. There may be a hole in the T cell repertoire. E. There may be blocking antibodies present which bind to soluble tumor antigens.
C. Tumor antigens may be recognized by T-cells in the absence of MHC.
Sam, a ten month old child, has recurrent bacterial infections, but not viral infections. Tests show few circulating B cells. This is consistent with A. chronic mucocutaneous candidiasis. B. C8 deficiency C. X-linked agammaglobulinemia. D. severe combined immunodeficiency disease.
C. X-linked agammaglobulinemia.
An intern working on your medical service accidentally pricks himself with a needle used to draw blood from a patient believed to be Hepatitis B positive. Optimal post exposure treatment for this person would be: A. begin vaccination with recombinant Hepatitis B vaccine only. B. administration of Hepatitis B immune globulin only. C. administration of Hepatitis B immune globulin and immunization at different sites. E. none of the above is required if the person is healthy
C. administration of Hepatitis B immune globulin and immunization at different sites.
36. An antigen found in relatively high concentration in the plasma of normal fetuses and a high proportion of patients testicular cancer is: A. viral antigen. B. carcinoembryonic antigen C. alpha-fetoprotein D. heterophile antigen
C. alpha-fetoprotein
All of the following are true EXCEPT A. An epitope is a small portion of a macromolecule B. the variable region domains contain the antigen recognition site C. an antigenic determinant is a paratope D. The class of an immunoglobulin is determined by its heavy chain E. An IgG antibody is bivalent
C. an antigenic determinant is a paratope
The immunoglobulin Joining chain (J-chain) is A. only produced by T-Cells B. only produced by neutrophils C. associated with only multimeric forms of lgM and IgA D. associated with IgE for histamine release E. only produced by mast cells
C. associated with only multimeric forms of lgM and IgA
A kidney biopsy specimen taken from a patient with acute glomerulonephritis and stained with fluorescein-conjugated anti-human IgG antibody would probably show: A. no fluorescence B. uniform fluorescence of the glomerular basement membrane. C. patchy, irregular fluorescence of the glomerular basement membrane. D. fluorescent B cells. E. fluorescent macrophages.
C. patchy, irregular fluorescence of the glomerular basement membrane.
One principal function of the Class I and Class II major histocompatibility complex S proteins is to A. transduce the signal to the T-cell interior following antigen binding B. mediate immunoglobulin class switching C. present antigen for recognition by the T-cell antigen receptor D. stimulate production of interleukins E. bind complement
C. present antigen for recognition by the T-cell antigen receptor
Three weeks after a bone marrow transplant, the patient began to experience diarrhea and a skin rash on the palms and soles of the feet spreading to the trunk. This is highly suggestive of graft versus (GVHD) host disease. All the following are correct regarding GVHD EXCEPT: A. requires immunocompetent donor cells. B. may result from infusion of blood products that contain viable lymphocytes into an immunologically incompetent recipient. C. requires suppressor T-cells. D. requires MHC differences between donor and recipient.
C. requires suppressor T-cells.
When a B-cell undergoes immunoglobulin class switching A. the variable region of the light chain changes, but its constant region remains the sam B. the variable region of the light chain remains the same, but its constant region changes C. the variable region of the heavy chain remains the same but its constant region changes D. the variable region of the heavy chain changes but its constant region remains the same E. both the variable and constant regions change
C. the variable region of the heavy chain remains the same but its constant region changes
Each of the following is a characteristic of antibodies, EXCEPT which one? A. they are proteins with variable and constant regions B. they contain carbohydrates C. they are only secreted by T-cells D. they can combine very specifically with antigen E. they are structurally organized in globular domains
C. they are only secreted by T-cells
52. A 6-year-old male was hospitalized for bacterial meningitis. Cultures of sputum and CSF yielded many colonies of Haemophilus influenzae . Past history indicated that the patient had numerous bacterial infections including seven episodes of pneumonia. Physical exam showed that tonsillar tissue was scanty. A lymph node biopsy revealed that germinal centers were absent, but that paracortical and medullary areas had normal numbers of lymphocytes. A mumps skin test was positive. Additional studies on this patient would probably show: A. a normal in vitro response to PHA. B. absence of T-cells. C. very low (less than 200-mg/dl) serum immunoglobulin levels. D. a positive NBT test
C. very low (less than 200-mg/dl) serum immunoglobulin levels.
A 25-year-old man who recently sustained a severe, dirty laceration of his right foot is brought to you. He has never received any immunizations. At age 7 he had tetanus. He was treated with penicillin and tetanus immune globulin (human). Fortunately, he recovered. Which of the following would you do to prevent tetanus now? A. Immunize with tetanus toxoid, which will stimulate a secondary antibody response. B. Administer tetanus immune globulin (human) to passively immunize the patient. C. Administer tetanus immune globulin (human) in addition to tetanus toxoid, because you cannot depend on a secondary immune response after 18 years. D. Administer tetanus immune globulin (human) plus tetanus toxoid, because the patient has absolutely no immunity to tetanus. E. Give no injection, because the residual immunity from the clinical tetanus will protect the patient.
D. Administer tetanus immune globulin (human) plus tetanus toxoid, because the patient has absolutely no immunity to tetanus.
Which of the following statements best characterizes an antibody? A. An antibody contains high molecular weight RNA as its basic structure. B. An antibody is composed of protein and cannot be distinguished from the albumin fraction of the serum proteins. C. An antibody is composed of four identical protein subunits which may be caused to dissociate by treatment with urea. D. An antibody contains protein as its major chemical component and its synthesis may be elicited by the administration of a foreign protein or polysaccharide. E. An antibody contains mucopolysaccharides as its major chemical component and the synthesis of these may be elicited by the administration of a foreign protein or polysaccharide.
D. An antibody contains protein as its major chemical component and its synthesis may be elicited by the administration of a foreign protein or polysaccharide.
Systemic Lupus Erythematosus (SLE), is characterized by immune complexes in serum and the basement membranes of many organs and joints. This involves Polyclonal B-cell activation resulting in increased production of IgM and IgG, which activate complement. Which of the following complement proteins functions as a chemotactic attractant for neutrophils, as well as an anaphylatoxin? A. C3a B. C3b C. C4a D. C5a E. C2b
D. C5a
The major immunoglobulin family to which a particular immunoglobulin belongs can be determined by sequential analysis of the 110 amino acids beginning from the A. Amino terminus of the light chain. B. Carboxy terminus of the light chain. C. Amino terminus of the heavy chain. D. Carboxy terminus of the heavy chain. E. None of the above
D. Carboxy terminus of the heavy chain.
A child has come in to your clinic repeatedly with thrush. You have prescribed anti-fungal treatment, which is successful only temporarily. His T-cell count appears to be normal and B-cells appear to be elevated during bacterial and viral infections. He is healthy despite this and shows no other signs of illness. Being the astute SGU physician that you are, you suspect: A. DiGeorges Syndrome B. Selective IgG deficiency C. Severe combined immune deficiency D. Chronic mucocutaneous candidiasis E. Biotin deficiency
D. Chronic mucocutaneous candidiasis
A 24-year-old primigravida after an uneventful pregnancy delivered a male baby at term. Upon neonatal examination, the baby was found to have low set ears, microcephaly (small head), rock bottom feet, cynosis (bluish discoloration) of the body due to severe congenital anomaly of the heart. Within 24 hours, the child died of severe hypocalcemic convulsions. Autopsy findings revealed redimentary thymus, total agenesis of parathyroid glands and severe ventricular and atrial defects of the heart. Based on the history, what is the most presumptive diagnosis? A. Bruton's syndrome B. X-linked agammaglobulinemia C. Severe combined immunoglobulin deficiency (SCID) D. DiGeorge's syndrome E. Selective variable immunoglobulin deficiency
D. DiGeorge's syndrome
A new employee in the SPCA was bitten by a rabid dog. The worker was brought to the Emergency Department even though he had been inoculated for tetanus, only three days before he was bitten. The attending physician ordered treatment with anti-rabies immune human globulin. Which one of the following describes the type of immunization the patient received in the emergency unit? A. Active natural immunity. B. Active artificial immunity. C. Passive natural immunity. D. Passive artifical immunity. E. None of the above.
D. Passive artifical immunity.
A car accident victim, who is 12-year-old, suffered lacerations when she was thrown clear of the vehicle. She has just been brought into the hospital. Her parents stated that she has not had previous immunization against tetanus. To provide protection against the possibility of tetanus now and in the future, which of the following is the preferred method of treatment? A. A mixture of tetanus toxoid and tetanus antitoxin as one injection, thereby causing less pain and producing an adjucant effect. B. A tetanus antitoxin injection this visit. C. A tetanus toxoid injection this visit, with an injection of tetanus antitoxin approximately three weeks later. D. Separate injections of tetanus toxoid and tetanus antitoxin in different sites on this visit to ensure active and passive immunization. E. None of the above.
D. Separate injections of tetanus toxoid and tetanus antitoxin in different sites on this visit to ensure active and passive immunization.
A 52-year-old patient returns for a routine follow-up to an Oncology Clinic six months after surgical removal of a tumor. Physical examination and functional inquiry were within the normal limits. However, laboratory results revealed an elevated level of serum carcinoembryonic antigen (CEA). Which is the LEAST likely diagnosis? A. Cancer of the colon. B. Stomach cancer. C. Breast cancer. D. Testicular teratocarcinoma. E. Lung cancer.
D. Testicular teratocarcinoma.
Infantile X-linked agammaglobulinemia occurs in male infants, who begin to suffer from recurrent bacterial infections at about 6-12 months of age. Patients have virtually no B lymphocytes. Which of the following is TRUE? A. The B cell response is intact, but the defect is in antigen processing. B. The defect may be in stem cell differentiation, as indicated by the occurrence of global immunodeficiency. C. The disease is most easily diagnosed by measuring CD4+ lymphocytes in the patient's peripheral blood. D. The age of onset of infections is due to disappearance of maternal antibody.
D. The age of onset of infections is due to disappearance of maternal antibody.
Which of the following best describes the differences between the classic and alternate complement pathways? A. The classic pathway results in the lysis of the target cell, which is not the case with the alternate pathway. B. The alternate pathway requires antibody for initiation, and the classic pathway is antibody-independent. C. The classic pathway is more active than the alternate pathway. D. The alternate pathway typically requires C3b for activation, while the classical pathway typically requires antigen-antibody complexes.
D. The alternate pathway typically requires C3b for activation, while the classical pathway typically requires antigen-antibody complexes.
A 24-year-old known atopic patient presented to the out patient medical clinic on a quiet spring afternoon with history of dry cough, wheeze and breathlessness. Upon examination, the patient was found to be under to moderate respiratory distress with bilateral lung wheezes. The patient's previous health records revealed that he was treated several times for acute allergic bronchial asthma. All of the following are correct concerning the immunological disorder presented in the above patient EXCEPT: A. it is immunological E (IgE) mediated reaction. B. the IgE antibodies that had developed during the initial exposures are bound to the mast cells and basophils. C. The present clinical symptoms are due to the release of vasoactive amines from the mast cells and basophils. D. The complement factors 'B' and 'D' have an active role in the release of various immunological mediators of the Type I hypersensitivity. E. Antihistamines, Epinephrine and Corticosteroids are life saving drugs that are commonly used for above immunological disorder.
D. The complement factors 'B' and 'D' have an active role in the release of various immunological mediators of the Type I hypersensitivity.
Which of the following is NOT true of interleukins? A. They are cytokines which can be produced by various cells of the immune system. B. They are hormones which allow one cell to communicate with another cell. C. They are in need of receptors on the target cell in order to mediate their effects. D. They are able bind antigen with a high level of specificity. E. They are able to modulate various aspects of the B-cell arm of immune system.
D. They are able bind antigen with a high level of specificity.
Positive skin tests to Candida albicans or tuberculoprotein have certain aspects in common with a reaction to poison ivy. These similarities include the following: A. They both are chemical responses to caustic irritants. B. They both are due to IgE antibody. C. They both occur within 1 hour of antigen exposure. D. They both are T cell-mediated.
D. They both are T cell-mediated.
If you could analyze, at the molecular level, a plasma cell that is making IgG antibody, you would find the following: A. mRNA specific for J chains. B. DNA sequence for VD and J genes translocated near the kappa-DNA exon. C. the c-myc gene translocated near the gamma-DNA exon. D. a DNA sequence for VD and J genes translocated near the gamma-DNA exon. E. mRNA specific for both the kappa and lambda light chains.
D. a DNA sequence for VD and J genes translocated near the gamma-DNA exon.
You are called to assess a patient in the midst of a rapid blood transfusion for an acute blood loss. She has spiked a fever and feels terribly unwell. You stop the transfusion, infuse saline, and draw blood for typing. This patient is O positive. The most likely cause of the reaction is: A. anti-A reactivity in the recipient. B. anti-B reactivity in the recipient. C. anti-A and anti-B reactivity in the donor. D. could be any of the above
D. could be any of the above
When immune complexes from the serum are deposited on glomerular basement membrane. Subsequent damage to the membrane is caused mainly by which one of the following? A. natural killer cells B. major basic protein released by eosinophils C. cytotoxic T cells D. enzymes released by polymorphonuclear cells
D. enzymes released by polymorphonuclear cells
The class of an immunoglobulin A. is determined by Class I and Class II major histocompatibility complex proteins B. is determined by the carbohydrate attached to the light chain is C. determined by the antigen D. is determined by the heavy chain type E. Is determined by the J-chain
D. is determined by the heavy chain type
Tumors may escape immunosurveillance by any of the following EXCEPT: A. lack of cells recognizing the tumor antigen. B. inability of patients MHC to present that particular tumor antigen. C. antigenic modulation or masking. D. local overexpression of cytokines IL-2 and/or TNF. E. failure to provide costimulation to develop anti-tumor immunity.
D. local overexpression of cytokines IL-2 and/or TNF.
15. With reference to the clonal selection theory, the following are true EXCEPT: A. B and T lymphocytes of all antigenic specificities exist prior to contact with antigen. B. each lymphocyte carries an antigen receptor on its surface of only a single specificity. C. lymphocytes can be stimulated by antigen under appropriate conditions to give rise to progeny with identical antigenic specificity. D. lymphocytes bear multipotential receptors which become specific after contact with antigen.
D. lymphocytes bear multipotential receptors which become specific after contact with antigen.
The basis for the control which MHC molecules have over the immune response is best explained by the: A. ability of MHC-antigen complexes to be released from antigen presenting cells and stimulate the activation of lymphocytes. B. expression of MHC gene products on effector T and B lymphocytes C. existence of genes controlling the immune response in linkage disequilibrium with MHC genes. D. need for antigen-derived peptides to bind an MHC class I or class II molecule for proper presentation to the receptor of a T lymphocyte. E. special affinity of unprocessed antigens for MHC molecules.
D. need for antigen-derived peptides to bind an MHC class I or class II molecule for proper presentation to the receptor of a T lymphocyte.
A 4-year-old child suffering from repeated pyogenic infections was found to have normal phagocytic function and cell mediated immune responses. Lymph node biopsy would probably reveal: A. depletion of thymus dependent regions. B. intact germinal centers. C. absence of dendritic cells. D. paucity of plasma cells.
D. paucity of plasma cells.
Which of the following is NOT true of T4 and T8 cell markers? A. These are both surface glycoproteins expressed on T-cells. B. These serve to distinguish different types of T-cells, e.g., helper, suppressor and cytotoxic, from each other. C. These are not found associated with immunoglobulins. D. The T4 proteins serve both to mediate T-cell helper function as well as the receptor for the AIDS virus. E. Both of the markers are present on ALL T-cells.
E. Both of the markers are present on ALL T-cells.
A patient walks into your clinic complaining of a chronic cough and general fatigue. Upon examination you diagnose him to have small cell lung cancer. Since the patient has a very aggressive form of cancer, that has been unresponsive to medication or radiation, you decide to enroll him in a new clinical trial that is using gene therapy to treat lung cancer. The theory behind the trial is to use gene therapy to express a protein on the cell surface that will stimulate T-cell proliferation upon immune surveillance of the tumor cells. Which of the following would be the most effective co-stimulatory protein to be expressed on the tumor cell in this clinical trial? A. CD28 B. I-CAM 2 C. LFA-3 D. CD40-L E. CD80/CD86
E. CD80/CD86
A 51-year-old man had a kidney transplant. Following the transplant, he had reduced renal function, which cytokine would be LEAST likely to play a role in this? A. IL-2 B. IFN C. IL-12 D. TNF E. IL-4
E. IL-4
The immunoglobulin class which is the least abundant in the normal adult is A. IgG B. IgA C. IgM D. IgD E. IgE.
E. IgE.
Multiple myeloma is a disease that affects primarily the elderly. It is characterized by the proliferation of a single clone of Ig secreting plasma cells. Sam, a retired engineer has been diagnosed with multiple myeloma in which the plasma cells secrete IgG. In Sam, which of the following would be competitively inhibited due to the multiple myeloma? (Assume that the specificity of the IgG is to an antigen to which Sam would never be exposed.) A. ADCC mediated lysis of target cells (e.g. virally infected cells) by natural killer cells. B. Opsonization by phagocytes when the opsonin is IgG. C. Neutralization of both viruses and toxin D. Only a and b E. None of the above
E. None of the above
Which of the following is NOT true of the ability of the T-cell receptor (TCR) to specifically recognize antigen? A. The antigen must be "processed" first by an accessory cell of immune system in order for it to bind to the TCR. B. The recognition of the antigen by the TCR can mediate helper, suppressor or cytotoxic function. C. The recognition of antigen by the TCR can result in cytokine secretion and/or an increase in cell proliferation within the immune system. D. The antigen is recognized by the T3-TCR complex only when it is associated with a protein of the major histocompatibility complex E. Only the alpha chain of the TCR is necessary for antigen
E. Only the alpha chain of the TCR is necessary for antigen
All of the following are true about antibodies, EXCEPT which one? A. They fix complement. B. They occur on the surface of B-lymphocyte C. They predominate the primary immune response to antigen. D. They are glycoproteins. E. They are molecule with a single, defined amino acid sequence.
E. They are molecule with a single, defined amino acid sequence.
All of the following are true of antigen EXCEPT which one of the following? A. They contain epitopes. B. They will react with antibodies. C. They contain antigenic determinants. D. They can elicit an immune response. E. They contain paratopes.
E. They contain paratopes.
A mother is Rh-. Her first baby is Rh+. During the delivery, some of the fetal blood enters the mother's blood stream. She develops a strong response which includes isotype switching to IgG. These antibodies recognize the Rh molecules that were present on the baby's red blood cells. This is unfortunate for the second fetus because IgG antibodies can cross the placenta. Consequently, the IgG can harm the second fetus if it is also Rh+. The newborn second child is suspected of having "hemolytic disease of the newborn". A Coombs test is performed to determine if the cause of the anemia is the presence of the mother's antibodies to the Rh+ molecule on the RBC of this second child. A Coombs test would require: A. a serum sample containing the mother's antibodies. B. a blood sample containing the baby's red blood cells. C. a labeled animal antibody that recognizes the Fc region of IgG. D. a + b E. b + c
E. b + c
A 24-year-old medical student is having some difficulty in understanding the role that antibodies play in the destruction of cells due to complement lysis. The professor decides that "seeing is believing" and so sends the student to the laboratory. The student is given two flasks. One flask contains antibodies isolated from an individual whose ABO phenotype is A. In the other flask there are red blood cells from an individual whose phenotype is unknown. The student is directed to put the red blood cells into the dish containing agar, and to add the isolated antibodies. In the second step, the student is directed to add all the complement proteins, required for cell lysis, to the agar dish. Following incubation of 37oC, the red blood cells are lysed. The phenotype of the individual from whom the red blood cells were isolated could have been: A. only AB B. only B C. only A D. either AB, B or A E. either AB or B
E. either AB or B
Activation of the complement cascade plays an important role in host defense by all of the following EXCEPT: A. working via the classical pathway, together with antibody, to induce bacteriolysis. B. mediating bacteriolysis directly, via the alternative pathway, in the absence of specific antibody. C. facilitating phagocytosis by generating opsonins. D. attracting phagocytes to the site of an infection by generating chemotaxins. E. enhancing the generation of reactive oxygen intermediates
E. enhancing the generation of reactive oxygen intermediates
Individuals unable to make the J protein found in certain immunoglobulins would be expected to have frequent infections of the A. brain. B. blood. C. liver. D. pancreas. E. intestinal tract.
E. intestinal tract.
All of the following are true with respect to IgM antibodies EXCEPT which one A. they fix complement B. they occur on the surface of lymphocytes C. they predominate in the primary response to antigen D. they are glycoproteins E. they mediate allergic reaction
E. they mediate allergic reaction
