Quantifying HLA-specific antibodies in patients undergoing desensitization

Purpose of review Two major desensitization protocols have been used to eliminate or reduce HLA antibodies to a level that allows transplantation with a low risk of antibody-mediated rejection (AMR). This review will focus on the antibody testing methods used to assess changes in the breadth and strength of antibody levels and the relative strength of donor HLA-specific antibodies (DHSAs). Recent findings Correlations of solid-phase immunoassay (SPI) class I and II levels with the donor-specific T and B cross-match results have shown the acceptable levels of DHSA that correlate with a low risk for AMR. The DSHA levels determined by SPI correlate with cross-match results and with clinical outcome. Therefore, the results of either assay can be used to determine the risk of AMR and when treatment has reduced DSHA to a level safe for transplantation. Monitoring DSHA is important for guiding the number of treatments as well as the timing of additional treatments needed to achieve these acceptable levels. Summary DSHA monitoring, in both protocols, uses the correlation of solid-phase antibody testing and the donor-specific cross-match to determine the efficacy of the protocol and when the acceptable level of DSHA is achieved permitting transplantation with minimal likelihood of AMR.