Question

1. Indicate what step is correct (Select all that apply)

1. Lymphocytes travel through the body in the lymph as well as the blood
2. Lymphocytes leave the blood through the walls of fine capillaries in 2ry lymphoid organs
3. After spending some time in the LN, lymphocytes leave in the efferent lymph
4. Lymphocytes return to blood at the subclavian vein
5. A lymphocyte after encounter an antigen to which its receptor binds, stops recirculating.
6. The spleen has no connection to the lymphatic system
7. Lymphocytes enter and leave the spleen through blood vessels

2. All of the following occur after B cells leave the bone marrow except

1. Peripheral Tolerance
2. Receptor editing
3. Differentiation into plasma cells
4. Production of memory B cells
5. Recirculation between lymph, blood, and 2ry lymphoid tissues

3. Developing B cells that fail to make productive D to J heavy-chain rearrangements on both homologous chromosomes

1. Die by apoptosis in the bone marrow
2. Will rearrange heavy-chain loci multiple times until a productive rearrangement is made
3. Undergo clonal proliferation
4. Fail to rearrange V to DJ

4. The antigen binding site is formed by the ----------------- of a heavy-chain V domain and a light-chain V domain

1. Allotypes
2. Complementarity-determining regions
3. Epitope
4. Fragment antigen binding region (Fab)
5. Isotype

5. Which of the following is not associated with mobilization of neutrophils to infected tissue?

1. TNF-\alpha production by macrophages
2. upregulation of selectins on blood vessel endothelium
3. interferon response
4. generation of a CXCL8 gradient
5. extravasation across endothelium

6. Identify which of the following statements regarding naïve T cells is incorrect

1. Naïve T cells enter lymph nodes from the blood or from the lymph
2. Naïve T cells can only be activated in 2ry lymphoid tissues
3. Naïve T cells differentiate into effector T cells after the encounter with the Ag
4. Naïve T cells are only activated by dendritic cells, not by macrophages or B cells
5. Naïve T cells occupy both the cortex and the medulla of lymph nodes

7. Which of the following explains why only dendritic cells are able to activate naïve T cells?

1. DC constituively express high levels of class II MHC molecules and upregulates B7 after activation during innate response
2. B cells require to be activated in order to express MHC class II molecules and costimulatory molecules
3. DC express higher levels of CTLA-4
4. Macrophages and B cells do not process antigens
5. Macrophages and B cells have higher level of B7 receptors

Answer 1

Answer 1. In this question, the steps A, B and D are correct.

Answer 2. The answer is B: Receptor editing.

Answer 3. The answer is C : Undergo clonal proliferation.

Answer 4. The answer is D: fragment antigen binding region (Fab).