Impact of Donor-Recipient Sex Mismatch on the Incidence of Allograft Rejection in Clinical Lung Transplantation: A Review of the United Network of Organ Sharing Database

Abstract

Purpose It is well-known that female animals mount immune responses against male-specific antigens, thought to be principally derived from proteins whose genes are Y chromosome-encoded. Although organ transplantation frequently involves donor-recipient sex mismatch, the immunological sequelae of such mismatches, particularly from male donor organs transplanted into female recipients, are unclear. Methods A review of the United Network of Organ Sharing (UNOS) database was conducted from 10/1987 to 12/2016. Recipient and graft survivals, and the incidences of acute rejection (AR)-related hospitalization and bronchiolitis obliterans syndrome (BOS), were determined across four groups: male donor-male recipient (dMrM, n = 12095), female donor-female recipient (dFrF, n=7444), female donor-male recipient (dFrM, n=3962) and male donor-female recipient (dMrF, n = 5766). Results AR-related hospitalization was specifically increased only in the dMrF group (p=0.006). In addition, severe BOS (Grade 3) was specifically increased only in the dMrF group (p Conclusion In clinical lung transplantation, female recipients of male allografts specifically exhibited significantly increased rates of AR and BOS. These findings are consistent with well-established immunological concepts and evidence, and have implications for donor-recipient matching in order to achieve optimal outcomes.