Evaluation of Desensitization Protocols in HLA-incompatible Kidney-transplant Candidates

Kidney transplantation is the best renal-replacement in the setting of end-stage renal disease. However, some transplant candidates have developed anti-HLA alloantibodies (human leukocyte antigen). When they are numerous and when their strength assessed by mean fluorescence intensity (MFI) is high it is very complicated to find-out a suitable kidney allograft against which the recipient has a negative cross-match. In such a case the only hope for the patient is desensitization therapy, whereby the treatment will decrease anti-HLA alloantibodies below a threshold, i.e. MFI \< 3,000, enabling kidney transplantation without risking antibody-mediated rejection. Desensitization relies on i) apheresis technics in order to withdraw circulating anti-HLA antibodies, and ii) immunosuppression, i.e. rituximab or tocilizumab, targeting B-lymphocytes, and tacrolimus/mycophenolic acid/steroids targeting T-cells. The type of apheresis is guided by the pre-desensitization MFI of anti-HLA alloantibodies, e.g. double filtration plasmapheresis or semispecific immunoadsorption. Likely the choice between rituximab and tocilizumab depends also on predesensitization anti-HLA antibody MFIs. At the end of the desensitization process, the patient will be able to get a kidney transplant either from a live-donor or from a deceased donor.