DIFFERENTIAL IGE RECEPTOR DEVELOPMENT ON RAT-TISSUE CULTURED MAST-CELLS

Rat tissue cultured mast cells established previously were cloned and subcloned by limiting dilution and analyzed for surface expression of both high- (Fc-epsilon-RI) and low-affinity (Fc-epsilon-R(L)) receptors for IgE. Analysis of receptor development in continuous culture over a period of 24 weeks revealed that Fc-epsilon-R(L) expression increased with time in all cases, irrespective of initial receptor density on the cell surface. Expression of Fc-epsilon-RI as measured in terms of its alpha-chain showed more clonal variation, exhibiting increases, decreases, as well as relative constancy over the time period. These results suggest that the two types of receptors are regulated independently and that some of the rat tissue cultured mast cell clones studied represent different stages of mast cell development.