Transplantation 08 22 14 Flashcards
transplantation antigens
major targets: MHC molecules
for hematopoietic stem cell grafts, MHC moecules or “minor” histocompatibility antigens
which MHC proteins have limited polymorphism?
HLA-C and HLA-DP
direct alloantigen recognition in transplant definition
recognizationof allogeneic MHC molecule from graft APCs
indirect alloantigen recognition in transplants
the allogeneic MHC moecules is taken up and processed by the recipient’s antigen presenting cell, then presented to T cell
autologous
self
allogeneic
from another person of the same species
xenogeneic
from another species
chimerism
mix of donor and recipient cells
hyperacute rejection in transplantation
not common in clinical transplantation
due to preformed antibodies
occurs within minutes
acute rejection in transplantation
can be cellular or humoral in nature
occurs in days to weeks in non-immune suppressed and in months to years in suppressed people
chronic rejection in transplantation
happens in months to years
vascular changes, interstitial fibrosis, loss or renal parenchyma
what kind of rejection occurs for allogeneic hematopoietic stem cell transplant.?
graft rejection
graft-vs-host disease
minor histocompability antigens
less potent at inducing graft rejection
cleaved and processed endogenous proteins that occupy binding groove of MHC class I and class II molecules
majority due to non-synonymous SNPs
encoded by multiple genes on multiple chromosomes
mixed lymphocyte rxn
mixing blood mononuclear cells from two donors in culture
primary concerns with solid organ allografts
immune mediated graft rejection
