Immunology Quiz#10: T Cell and B cell activation

1. A 23-year-old male presents with recurrent infections, including several bouts of pneumonia and a recent diagnosis of oral candidiasis. Laboratory tests reveal a significant decrease in CD4+ T cell count. This patient's increased susceptibility to infections is most likely due to a defect in which of the following processes? 

Question 1 of 7

2. A 35-year-old woman is diagnosed with systemic lupus erythematosus (SLE). She has high levels of autoantibodies in her serum. The formation of these autoantibodies is most likely initiated by a failure in which of the following processes? 

Question 2 of 7

3. During a laboratory class, a medical student learns that a certain co-stimulatory signal is required for the full activation of T cells after antigen recognition. This signal involves the interaction between two molecules, one on the surface of the antigen-presenting cell and the other on the T cell. Which of the following pairs of molecules is involved in this crucial co-stimulatory signal? 

Question 3 of 7

4. A researcher is studying the activation of B cells and observes that when a naïve B cell recognizes an antigen through its B cell receptor (BCR), it undergoes proliferation and differentiation. However, for a robust antibody response, especially isotype switching and affinity maturation, interaction with a second cell type is necessary. Which of the following cells provides the necessary signals for these processes? 

Question 4 of 7

5. A 27-year-old male presents with recurrent infections, including episodes of pneumonia and sinusitis. Laboratory tests reveal normal numbers of B cells but a significantly reduced level of serum immunoglobulins. Further testing indicates a defect in T cell help to B cells. Which of the following molecules is most likely deficient on the patient's T cells, leading to impaired B cell activation? 

Question 5 of 7

6. A 33-year-old woman is diagnosed with a bacterial infection. In the process of generating a robust immune response, her body activates T cells. Which of the following events is essential for the initial activation of a naïve T cell? 

Question 6 of 7

7. During an immunology class, a professor explains the process of B cell activation. For a B cell to be fully activated after binding its specific antigen, it requires help from T cells. This help involves a specific interaction between molecules on the surface of T cells and B cells. Which of the following pairs of molecules is primarily involved in this process? 

Question 7 of 7


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