Cartilage transplants in normal and preimmunized mice.

Syngeneic, H-Y incompatible and allogeneic rib and nasal cartilages from 5-day- and 8-week-old mice were transplanted into adult recipients. Some recipients of allogeneic transplants were preimmunized with splenocytes or chondrocytes from animals of the same strain as cartilage donors, and some with sheep red blood cells (SRBC). Syngeneic or allogeneic transplants independently of the age of the cartilage, did not evoke any detectable humoral or cellular response as judged by evaluation of the specific cytotoxic antibodies and indirect migration inhibition test, respectively. Allogeneic transplants of nasal cartilage were free of infiltrating lymphoid cells, but in the vicinity of rib cartilage grafts some lymphocytes were present. Animals preimmunized with allogeneic splenocytes or chondrocytes displayed both humoral and cellular response to donor cells. Allogeneic cartilage transplants from these animals were surrounded by heavy infiltrations. Preimmunization with SRBC did not evoke infiltrations around allogeneic cartilage grafts.