Immunological tolerance in human transplantation. The possible existence of a maternal effect

We analyzed data from 93 patients who received a kidney graft from their parents; 55 were transplanted with a kidney from their mothers (Mat.) and thirty-eight from their fathers (Pat.) The Pat. group has shown a better graft and patient survival as well as long-term renal function when compared with the Mat. group. This pattern was more evident with time. Long-term graft function assessed by creatinine levels also showed differences between the groups, favoring the Pat. group. The results are interesting since recent reports have claimed a tolerance developed by the individual to noninherited HLA antigens of their mother.