Distribution and redistribution of pancreatic islet cell surface antigen reactive with islet cell surface antibody in the rat.

Antigens on the rat pancreatic islet cell surface were redistributed into patch and cap formation when the cells were incubated in the presence of the phosphodiesterase inhibitor, 3-isobutyl-1-methylxanthine, in tissue culture medium 199 for 24 h, before addition of rat pancreatic islet cell surface antibody. In contrast, if the cells were cultured in tissue culture medium 199 supplemented with glucose (5.5 or 16.7mmol/l) and 10% heat-inactivated fetal calf serum without 3-isobutyl-1-methylxanthine, cap formation was not detectable. These results suggest that mobile antigen on the surface of pancreatic B cells can be induced to aggregate into patch and cap formations during conditions of increased cellular metabolism.