Variability of Response to the Female Histocompatibility Antigen in Chickens

Female integumental grafts on males are less likely to survive than are grafts exchanged in other sex combinations with some inbred lines of chickens. The rejection of female integument is commonplace in two inbred lines but cannot be detected in a third. Evidence for a second-set response is presented. This sex-specific rejection by males may be controlled by the W chromosome of the female chicken and is analogous to the rejection of male skin by females in some inbred lines of mice. A line in which males were responsive to the female histocompatibility antigen was reciprocally crossed with a nonresponsive line. F1 males rejected female grafts from both parental lines and from F1's in higher frequency than that for similar grafts in intrasex combinations on F1 males and females. The speed of rejection of female grafts on F1 males was less than that observed on responsive line males. We ascribe differences between lines in responsiveness to the female histocompatibility antigen to be primarily caused by differences in immunological competence.