Transplant

Question 1

whatv are the 3 stages of transplant rejection

Answer 1

1 - recognition - T cells recog HLA as foreign
2 - activation
3 effector function - CD8+ T cells damage transplant, Abs bind to graft endo

Question 2

what are the types of HLA and where are they expressed

Answer 2

HLAI (A, B, C) - on all cells
HLA II (DR, DQ, DP) - on APCs

Nb. HLA = MHC

Question 3

What 3 HLA subtypes are the most important in transplant rejection

Answer 3

DR > B > A

Question 4

how many HLA mismatches is the cutoff for assumed rejection

Answer 4

6 - counted in PCR

Question 5

how many HLA matches will a parent-child have

Answer 5

at least 3

Question 6

sibling to sibling HLA matches

Answer 6

25% = 6MM (perfect match)
50% = 3 MM

Question 7

what are the parts of T cell mediated rejection histology

Answer 7

lymphocyte interstitial infiltration
ruptured tubular BM
tubulitis (inflam cells in tubular endo)
macrophages

Question 8

what are the parts of Ab mediated rejection histology

Answer 8

inflam cell infiltrate
intravasc disease/capiliritis (inflam cells in microcirc)
endothelial damage

procoag -> closure of microcirc -> graft fibrosis

Question 9

path and timeframe of hyperacute rejection

Answer 9

mins-hrs
due to pre-formed abs (esp ABO)
-> thrombosis + necrosis

Question 10

path and timeframe of acute rejection

Answer 10

weeks-months
T med (-> tubulitis)
Ab med (->capiliritis)

Question 11

path and timeframe of chronis rejection

Answer 11

months-years

non immune damage to graft

Question 12

Tx for acute rejection

Answer 12

T cell immunosuppression

OR Ab removal and B cell immunosupp

Question 13

sympto of GVHD in stem cell transplant

Answer 13

skin rash, vom, bloody stool, jaundice