Overview of the immune biology of allogeneic hematopoietic stem cell transplantation - Immune Biology of Allogeneic Hematopoietic Stem Cell Transplantation - page 3

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FIGURE 1.1
(a) Tools in experimental GVHD. (b) Tools and challenges in studying human GVHD. KO = knock out; pbmnc = peripheral blood mononuclear cells.
that are critical to target cell identification and subsequent NK cell-mediated
killing (reviewed in chapter 15). During graft rejection, the effector pathways
used by recipient T cells differ on the basis of prior sensitization of the host
to alloantigen. In naïve, un-sensitized recipient mice, perforin, granzyme B
and Fas/FasL can mediate rejection of MHC- and/or MiHA mismatched BM
by CD8 + T cells. CD4 + T cells mediate allogeneic BM destruction. However,
CD8 + T cells from sensitized recipients with alloantigen can reject BM by
an unknown mechanism that appears independent of the numerous path-
ways, as determined using gene knockout mice and neutralizing antibod-
ies. Prior exposure to histocompatibility antigens, which can occur by blood