Solid phase assays for HLA antibody detection in clinical transplantation.

The complement dependent microlymphocytotoxicity assay has been used for over 40 years for detecting HLA antibodies in transplant patients. This method has been replaced recently by more sensitive solid phase assays such as ELISA and bead based technology including the Luminex method. The introduction of these techniques into clinical practice has revealed previously undetected sensitisation in some patients and allowed the accurate assignment of antibody specificities directed at HLA-DQ and HLA-DP which was not previously possible. However it is emerging that despite the advantage of sensitivity some HLA antibodies defined by these assays are not associated with hyperacute or acute rejection. The role in allograft rejection of antibody titre and non-complement fixing antibodies, which are also detected by these methods, are areas currently under consideration.