The humoral immune response to allografts of foetal small intestine in mice.

The influence of the presence of "passenger leucocytes" on the production of anti-H2 antibodies has been studied in mice receiving allografts of foetal small intestine, adult skin or intradermally injected spleen cells. It was found that the humoral immune response to foetal intestine (a tissue without passenger leucocytes) was identical temporarily to that elicited by skin allografts and these responses differed from that following injection of allogeneic spleen cells in that antibodies to solid grafts took longer to appear. The humoral immune response to small intestine grafts was not evident until several days after the onset of graft rejection as assessed morphologicallymanti H2 antibody production was not observed in thymus deprived recipients of foetal small intestine allografts or allogeneic spleen cells, and this suggests that the humoral immune response to transplantation antigens is thymus dependent.