CLINICAL RELEVANCE OF ANTI-HLA ANTIBODIES PRE AND POST TRANSPLANT

Pretransplant histocompatibility testing seeks to select compatible do nor-recipient pairs for transplantation. Sera from prospective renal t ransplant recipients are screened for the presence of human leukocyte antigen (HLA) antibodies to determine humoral alloimmunization, Presen t techniques screen patient sera using a complement-dependent cytotoxi city assay and express the results as percent of panel reactive antibo dy (PRA). However, the standard assay suffers because it needs viable target cells, a variable sensitivity of cells for complement, subjecti ve evaluation, a lack of standardized methodology, and a variable corr elation with clinical outcomes. Alternatively, an enzyme-linked immuno sorbent assay (ELISA) methodology can detect IgG anti-HLA reactivity b ased on the binding of immunoglobulin to soluble HLA class I antigens, This method provides increased objectivity and reproducibility, does not require use of viable target cells, and most importantly, detects immunoglobulin that is reactive to HLA class I antigens, Data discusse d herein suggest that identifying reactive recipient sera using the en zyme-linked immunosorbent assay (ELISA) (PRA-STAT, Sang Stat Med, Menl o Park, CA) methodology may be more informative clinically than curren t standard percent of panel reactive antibody (PRA) assays.