T Cell Immunity

Question 1

Examples of non enveloped viruses

Answer 1

norovirus and poliovirus

cause cell lysis

Question 2

examples of enveloped virus

Answer 2

influenza and HIV

Question 3

how do enveloped viruses infect cells

Answer 3

insert into cell membrane, progeny buds off

Question 4

what are virus envelope proteins targeted by?

Answer 4

antibody/complement

antibody dependent cytotoxic cells- apoptosis

Question 5

how do t cells recognise virus particles

Answer 5

peptides bound to MHC on APCs or infected cells are recognised by TCRs

Question 6

what is the main role of t cells

Answer 6

to eliminate microbes that survive inside cells mainly viruses

Question 7

where do VJDC gene fusions occur

Answer 7

in thymus

Question 8

what is thymic education

Answer 8

eliminates t cells that could potentially attack self antigens

Question 9

what is the more common type of TCR

Answer 9

aBTCR (99%)

remainder ydTCR

Question 10

what is positive selection

Answer 10

recognition of functional TCR and MCH

Question 11

what is negative selection

Answer 11

deletion of self reacting t cells - apoptotic cell death

Question 12

how many MHC copies do you inherit

Answer 12

one from mother one from father

co dominantly expressed - 2 of each 6 types

Question 13

how many MHC class 1 genes are there

Answer 13

3 - A,B,C

one gene each - a chain protein

Question 14

How many MHC class 2 genes are there

Answer 14

3 - DP, DQ, DR

2 genes each - a chain protein and B chain protein

Question 15

where are MHC 1 proteins expressed

Answer 15

on surface of nucleated cells

Question 16

where are MHC 2 genes expressed

Answer 16

on surface of APCs

Question 17

to what cell does MHC class 1 present self and virus antigens

Answer 17

cytotoxic t cells

Question 18

to what cell does MHC class 2 present foreign antigens

Answer 18

to helper t cells

Question 19

where are MHC I proteins degraded

Answer 19

proteosomes

Question 20

where are MHC II proteins degraded

Answer 20

endo lysosomes

Question 21

how do dendritic cells cross present to both t helper and ctls

Answer 21

present via MHC II to naive CTL

proteins transported to cytosol and enter MHC I pathway to Th cells