Beneficial HLA matching in centers using cyclosporine A

In this chapter the linear model for the relationship between cumulative HLA mismatches and graft loss is shown to be invalid. HLA-A and -B mismatches and HLA-DR mismatches appear to differ in potency. A single mismatch at the HLA-DR locus is associated with a maximum risk of graft loss. These findings permit a simple division of transplants into beneficially matched (000, 100, and 010) and nonbeneficially matched (all other 23 combinations). In centers where more than two-thirds of patients were treated with CsA at three months, a similar dichotomy between beneficially and nonbeneficially matched transplants was observed, confirming the view that CsA-treated patients benefit from good HLA-A,B and DR matching. Organ-sharing schemes are designed to realize the full potential of matching and their potential can be investigated by simulation studies. These indicate that if all organs were unconditionally offered to a multicenter pool of more than 3,000 recipients, more than 60% of transplants could be beneficially matched.