EARLY ANTIBODY PRODUCTION IN RELATION TO SKIN ALLOGRAFT REACTIONS IN MICE

Abstract

Antibody production was consistently demonstrable by the development of hemolytic plaque-forming cells in the spleen and lymph nodes as early as 2–3 days after orthotopic skin allografting in strain combinations involving strong histoincompatibility. In the reciprocal A/J → C57BL/6 and C57BL/10 → B10.A combinations, where the median survival times of skin allografts ranged from 8.2–108 days, the peak appearance of plaque-forming spleen cells after grafting was found at about 8 days in 3-hr incubation tests and as early as 3 days in 20-hr incubation tests of congenic H-2 incompatible cells. Regional lymph node cells from the same recipients gave much higher numbers of plaques which reached a maximal level at 3–5 days, a time when the process of graft rejection had only just begun. There was usually a 3–5-fold increase in the numbers of plaque-forming spleen and lymph node cells detectible after 20-hr vs. 3-hr test incubation periods. Although the early occurrence of plaque-forming cells, including blood lymphocytes, might be useful as an indicator of incipient organ allograft rejection, the functional role of the plaque-forming cells or their secreted antibodies in solid tissue allograft reactions remains to be elucidated. Despite the highly suggestive correspondence between the time-course of appearance of plaque-forming cells and of acute allograft rejection, a direct cause-and-effect relationship does not necessarily follow from the evidence available.