Lymphocytes I

Question 1

Describe Innate immunity.

Answer 1

Consists of germline encoded receptors that recognize pathogens. Response is fast and non-specific; no memory (p.193)

Question 2

What types of cells are involved in innate immunity?

Answer 2

Neutrophils, macrophages, dendritic cells, natural killer cells (lymphoid origin), and complement (p.193)

Question 3

Describe adaptive immunity.

Answer 3

Consists of receptors that undergo V(D)J recombination during lymphocyte development to recognize pathogens. Response is slow on first exposure but memory response is faster and more robust (p.193)

Question 4

What types of cells are involved in adaptive immunity?

Answer 4

T cells, B cells, circulating antibody (p.193)

Question 5

What types of genes encode MHC?

Answer 5

HLA (human leukocyte antigen) genes (p.194)

Question 6

What is the function of MHC class I and II?

Answer 6

To present antigen fragments to T cells and to bind TCRs (p.194)

Question 7

What three haplotypes are associated with MHC I?

Answer 7

HLA-A, HLA-B, HLA-C (p.194)

Question 8

To what does MHC I bind?

Answer 8

TCR and CD8 (p.194)

Question 9

On what types of cells is MHC I expressed?

Answer 9

All nucleated cells (p.194)

Question 10

On what types of cells is MHC I not expressed?

Answer 10

On RBCs (p.194)

Question 11

How is antigen loaded onto MHC I?

Answer 11

Antigen is loaded in the RER with mostly intracellular peptides (p.194)

Question 12

To what does MHC I pair?

Answer 12

Pairs with B2-microglobulin (p.194)

Question 13

What is the function of B2 microglobulin-MHC I binding?

Answer 13

Aids in MHC I transport to cell surfact (p.194)

Question 14

What type of immunity is mediated by MHC I?

Answer 14

Viral immunity (p.194)

Question 15

What three haplotypes are associated with MHC II?

Answer 15

HLA-DR, HLA-DP, HLA-DQ (p.194)

Question 16

To what does MHC II bind?

Answer 16

CD4 cells and TCR (p.194)

Question 17

On what types of cells is MHC II expressed?

Answer 17

Expressed only on antigen presenting cells (p.194)

Question 18

How is antigen loaded onto MHC II?

Answer 18

Antigen is loaded following release of the invariant chain in an acidified endosome (p.194)

Question 19

By what mechanisms do NK cells induce apoptosis?

Answer 19

Through perforin and granzymes NK cells induce apoptosis of virally infected and tumor cells (p.194)

Question 20

What cell type is the only lymphocyte member of the innate immune system?

Answer 20

Natural Killer (NK) cells (p.194)

Question 21

What four types of cytokines enhance NK cell activity?

Answer 21

IL-2, IL-12, IFN-b, IFN-a (p.194)

Question 22

What induces an NK cell to kill?

Answer 22

Exposure to a nonspecific activation signal on a target cell and/or absence of class I MHC on the target cell surface (p.194)

Question 23

What are the four general functions of B cells?

Answer 23

To make antibody, to assist in type I hypersensitivity (allergy) reactions, to assist in cytotoxic and immune complex (types II and III) hypersensitivity, and to function in hyperacute and humorally mediated acute and chronic organ rejection (p.195)

Question 24

What type of B cells opsonize bacteria and neutralize viruses?

Answer 24

What type of B cells opsonize bacteria and neutralize viruses?