Sex as a biological variable has been broadly studied in a variety of diseases including autoimmune diseases, cancer and infections. However, whether donor or recipient sex and sex hormone levels impact alloimmune responses remains unclear. Our clinical observations demonstrate age-specific inferior graft survival in female recipients; the experimental model validated the impact of estrogen levels on the fate of T cell subsets, together providing relevant and novel information on age- and sex-specific alloimmunity in solid organ transplantation.
While the impact of male hormones on immunity has been well studied and most experimental models remain to be performed using male animals, little research has been done on the impact of female hormones on alloimmunity. Our findings provided a new perspective that the sex- and sex hormone-related discrepancy should be considered in animal model application in immunological research.