too many questions
3 pointers??
injured players
fuel food
are they dying?
100
Defective function of which of the following proteins will result in failed CD8 T-cell priming?
A HLA-DM
B CLIP
C TAP 1/2
D Invariant chain
E HLA-DO
C TAP 1/2
100
what is an antigen ?
100
A 9-year-old child presents with frequent viral infections and prolonged recovery periods. Immunological examination reveals decreased levels of circulating T cells, particularly CD4-positive T cells. Which of the following markers is likely to be affected in this child's peripheral blood leukocytes?
A) CD8
B) CD19
C) CD56
D) CD25
E) CD3
A) CD8
100
A healthy 19-year-old male is exposed to an antigen for a second time. In addition to producing a different class of antibody after second exposure, small nucleotides changes result in the B-cell DNA encoding the V, and V, regions. This process is referred to as:
A Junctional diversity
B Allelic exclusion
C Somatic hypermutation
D Alternative RNA splicing
E Isotype switching
C) Somatic hypermutation
100
T cells stimulated by peptide-MHC complexes, dis- played on antigen presenting cells, in the absence of costimulation undergo which one of the following processes?
(A) Activation
(B) Anergy
(C) Apoptosis
(D) Differentiation
(E) Proliferation
The answer is B: Anergy.
200
Which of the following descriptions correctly indicates the role of tapasin in the process of peptide antigen presentation?
A Trims the amino terminus of peptides that are too long for MHC binding.
B Breaks and reforms disulfide bonds in the MHC I a domain during peptide loading.
C Protects the peptides produced in the cytosol from complete degradation.
D Retains the MHC class I molecule a chain in a partially folded state.
E Forms a bridge between the MHC class I molecule and the TAP complex.
D. Retains the MHC class I molecule α chain in a partially folded state.
200
jk it wont let me add pics but
Which lettered options of the T-cell Receptor molecule shown to the corresponding description below. Region that takes part in transducing the signal after antigen recognition.
The correct answer is option c. C.
The C region in the above image of T cell receptor represents the CD3 and zeta subunit which is necessary for transducing the signal after antigen recognition. The A region in the diagram is the region that recognize the antigen. The CD3 region has epsilion, delta and gamma units in it. The zeta unit is located in the cytoplamic region. B represents the constant domain.
200
A workup on an ill child revealed low levels of com- plement C3 in her blood. Which one of the following presentations did this child most likely manifest?
- Chroniceczema
- Immune hemolytic anemia
- Incomplete recovery from viral infections
- Poor response to vaccination
- Recurrent infections with extracellular bacteria
The answer is E: Recurrent infections with extracellular bacteria.
200
Which of the following immune cells is primarily responsible for coordinating the adaptive immune response by secreting cytokines and activating other immune cells?
A) Eosinophils
B) Mast cells
C) Helper T cells
D) Basophils
E) Natural killer (NK) cells
C) Helper T cells
200
A 47-year-old woman developed toxic shock follow- ing an infection with a strain of Staphylococcus aureus that produced toxic shock syndrome toxin (TSST)-1. This toxin binds directly to MHC Class II molecules on macrophages and which molecule on T cells?
- CD3
- CD4Oligand
- Fas ligand
- The gamma chain of the IL-2 receptor
- The variable beta portion of the T-cell receptor
The answer is 5: The variable beta portion of the T cell receptor.
300
Question: Which of the following proteins plays a critical role in the loading of peptides onto MHC class I molecules during antigen presentation?
A) Hsp70
B) Calnexin
C) Tapasin
D) Cathepsin D
E) Grp94
C) Tapasin
300
Somatic hypermutation and affinity maturation
A further diversify the C region of the immunoglobulin.
B are mostly induced by T independent antigens.
C occur in both BCR and TCR.
D involve the recombination of specific switch regions.
E take place within germinal centers.
E) take place within germinal centers.
300
A 12-month old child is referred to a specialist because of recurrent bacterial infections and failure to thrive. A lymph node biopsy reveals the absence of germinal centers. Which of the following markers is likely to be absent from peripheral blood leukocytes in this child?
A CD3
B CD4
C CD8
D CD14
E CD19
E) CD19
300
Which of the following cell types is primarily responsible for the production of antibodies in the adaptive immune response?
A) Macrophages
B) Dendritic cells
C) Natural killer (NK) cells
D) T lymphocytes
E) Plasma cells
E) Plasma cells
300
A 1-year-old female presented with symptoms of systemic autoimmunity (lupus, diabetes, and arthritis), and upon genetic analysis it was found that the patient had a mutation in the Foxp3 gene locus. Which one of the following is an explanation for the clinical symptoms observed?
(A) Patient cannot produce antigen presenting cells
(B) Patient cannot generate regulatory CD4+CD25+
T cells cell types.
(C) Patient is unable to produce antibodies
(D) Patient cannot produce anti-inflammatory cytokines
(E) Patient NK cells have no inhibitory signal
The answer is B: Patient cannot generate regulatory CD4+CD25+ T cells.
400
Which of the following is a feature of the innate immune response?
A Memory
B Delayed Response
C Specificity
D Activation by pathogen-associated molecular patterns
D) Activation by pathogen-associated molecular patterns
400
Which of the following is the site at which lymphocytes can leave the blood and gain entry into the lymph nodes?
A Periarterial lymphatic sheath
B Thoracic duct
С High endothelial venules
D Lymphoid follicle
E Germinal center
C) High endothelial venules
400
Which one of the following represents the major role of negative selection in the thymus?
(A) Elimination of self-reactive
T cells
(B) Expansion of nonself-reactive
Tcells
(C) Maturation of professional antigen presenting cells such as dendritic cells
(D) Expression of T-cell receptors on mature T cells
(E) Differentiation of Thl and Th
The answer is A: Elimination of self-reactive T cells.
400
Which of the following is responsible for the production of antibodies in the adaptive immune response?
A T cells
B NK Cells
C Monocytes
D Neutrophils
E B Cells
E) B Cells
400
A 34-year-old male receives a minor cut on his thumb. A dendritic cell ingests and kills some of the bacteria it finds in the cut, and fragments of the bacteria are placed onto the surface. In which of the following sites is the dendritic cell most likely to interact with an antigen-specific T-cell to generate an immune response capable of further attacking bacteria still at the original site of infection?
A The liver
B The skin of the thumb
C A lymph node
D The bone marrow
E Blood capillaries in the thumb
C) A lymph node
500
What is the difference between an antigen and an immunogen?
A Antigens are molecules that induce an immune response, while immunogens are molecules that bind to antibodies.
B Antigens are foreign substances that enter the body, while immunogens are substances that the body recognizes as "self."
C Antigens are molecules that are recognized by the immune system, while immunogens are molecules that activate the immune system.
D Antigens and immunogens are interchangeable terms that refer to any molecule that interacts with the immune
C) Antigens are molecules that are recognized by the immune system, while immunogens are molecules that activate the immune system.
500
Positive selection in the thymus occurs when thymocytes express a functional version of which critical molecule?
A T-cell receptor
B TLR-4
C MHCI
D CD28
E Fc receptor
A) T-cell receptor
500
A 26-year-old obstetric patient becomes ill during the first trimester of pregnancy with fever and lymphadenopathy. She is found to have a rising titer of anti-Toxoplasma gondii (parasite) antibodies. She delivers a full-term baby with no apparent signs of in utero infection. The best way to diagnose acute infection in the neonate would be a parasite-specific ELISA for which isotype of immunoglobulin?
A IgM
B IgD
C IgE
D IgG
E IgA
A) IgM
500
A 25-year-old man presents to the emergency department with a fever and a painful, swollen right leg. He reports that he has been experiencing pain and redness in his leg for the past week, which has progressively worsened. On examination, the man has a temperature of 39°C and a swollen, tender, and erythematous right leg. Blood tests reveal an elevated white blood cell count with a left shift, indicating a bacterial infection. Further tests show that the man has a genetic defect that impairs the function of his neutrophils. Which of the following neutrophil functions is most likely affected in this patient?
A Antibody production
В Antigen Presentation
C Phagocytosis
D Cytokine production
C) Phagocytosis
500
A 4-year-old child has atopic dermatitis due to severe allergies to dust, animal dander, and many kinds of pollens. Mediators released from which cell type are responsible for the clinical manifestations immediately following exposure to these substances?
- Bcells
- Macrophages
- Mast cells
- Thl cells
- Th2cells
The answer is C: Mast cells.