MLC inhibitory alloantibodies and outcome of kidney allografts

Sera from individuals who have been sensitized to transplantation antigens often display MLC inhibitory activity (MLC-IA). Both anti-SD (HLA-A,B) and anti-LD (HKA-D) antibodies share the capacity of inhibiting the MLC reaction. Some studies suggest that MLC-IA, when present in pretransplantation sera, correlates positively with successful kidney transplantation and that this reflects a protective or 'enhancing' effect mediated by anti-LD antibodies. In contrast, other studies, as well as our own, indicate that MLC blocking correlates mostly with humoral rejection. This article presents an update of our studies on the correlation between the development of MLC-IA in recipients of cadaveric kidneys or of the kidneys from HLA-half-identical living related donors.