Pemphigus antibodies fixation and keratinocyte differentiation in organ cultures. Effects of some agents influencing the intracellular content of cyclic AMP.

The effect of some agents, influencing the cyclic adenosine 3', 5'-monophosphate (cAMP) content of human cells, on the ability of the keratinocytes of binding pemphigus antibodies was studied by using tissue cultures of rabbit esophagus. As demonstrated by immunofluorescence (IF) for IgG, the bound antibodies appeared markedly decreased on esophagus explants grown under standard conditions, that is without test agents, when compared to ones fixed on fresh esophagus. But the IF reaction was remarkably more intense when methylxanthines or epinephrine were added to the growth medium of the cultures. Following the addition of these agents to the cultures some histologic modifications appeared in the explants, indicating that the keratinization process had probably been stimulated. This temporal relationship of immunofluorescence and histologic findings seems to suggest the hypothesis that keratinocyte differentiation, regulation of cAMP intracellular content, and pemphigus antibodies fixation are related processes.