lymphocytes

Question 1

innate immune cells?

Answer 1

macrophage, neutrophil (non specific)

Question 2

adaptive immune cells?

Answer 2

T cells and b cells

Question 3

What immune response do T cells mediate?

Answer 3

the cell mediated response

Question 4

roles of T cells?

Answer 4

produce cytokines to help immune response (CD4)
kill infected cells (CD8)

Question 5

what immune response to B cells mediate?

Answer 5

humoral response

Question 6

role of B cells

Answer 6

produce antibodies

Question 7

what is an epitope?

Answer 7

a region of an antigen which an antibody binds to

Question 8

what is clonal expansion triggered by?

Answer 8

interaction between a foreign molecule and a B cell’s unique receptor

Question 9

How is antigen receptor diversity generated?

Answer 9

BCR chain is encoded by separate multigene families on different chromosomes

during B cell maturation, the gene segments are rearranged and brought together (immunoglobulin gene arrangement)

Question 10

What’s the MHC?

Answer 10

Major histocompatibility complex- presents antigens to T cells

Question 11

which MHCs do CD4 and CD8 bind to respectively?

Answer 11

CD4 is MHCII (extracellular), CD8 is MHCI (intracellular)

Question 12

how do CD8 cells kill their targets?

Answer 12

apoptosis- store perforin, granzymes, granulysin in cytotoxic granules released after target cell recognition

perforin molecules polymerise and form pores

Question 13

3 core protective roles of antibodies?

Answer 13

neutralisation. opsonisation, complement activation

Question 14

What does IgG do?

Answer 14

opsonisation and neutralisation

Question 15

what does IgM do?

Answer 15

produced first upon antigen invasion- increases transiently

Question 16

characteristics of IgA

Answer 16

expressed in mucosal tissue
forms dimers after secretion

Question 17

characteristics of IgE

Answer 17

involved in allergy

Question 18

What determines the antibody a B cell will make?

Answer 18

the BCR (has a unique binding site which binds to the epitope)

Question 19

What do naive B cells require to be activated?

Answer 19

am accessory signal either:
1. directly from microbial constituents
2. T helper cell

Question 20

What can thymus-independent antigens do?

Answer 20

directly activate B cels without T cells

2nd signal provided by a bacterial PAMP

needs to have a repetitive (usually polysaccharide) structure