K. Herrlinger et al., CELL-MEDIATED IMMUNE REACTIVITY IN THE XENOGENEIC TRANSPLANTATION COMBINATION HUMAN-ANTI-PIG, Zentralblatt fur Chirurgie, 123(7), 1998, pp. 803-808
The worldwide lack of human organ donors puts the pig as potential xen
ogeneic donor species into the prime of interest. Aim of the present i
n vitro study is the analysis of T-cell activation in the clinically a
ttractive combination ''pig-to-human''. Peripheral human blood leukocy
tes (hPBL) and peripheral porcine blood leukocytes (pPBL) were co-cult
ered for 4-8 days in the xenogeneic mixed lymphocyte reaction (xMLR) a
nd cell proliferation was measured by H-3-thymidine uptake. Both cell
populations were separated into T-cells and antigen presenting cells (
APC) to analyze direct and indirect antigen recognition. The results s
how that (a) activation of human T-cells occurs, (b) the strength of a
ctivation depends e.g. on the human responder (''high'' and ''low'' re
sponders), (c) the strength of activation is independent of the respon
der's HLA-DR status, and (d) direct T-cell activation dominates over i
ndirect activation. Thus, T-cell activation is another immunological b
arrier that has to be overcome before xenotransplantation can be clini
cally approached.