GASTRIC PARIETAL-CELL ANTIBODIES - DEMONSTRATION BY IMMUNOFLUORESCENCE OF THEIR REACTIVITY WITH THE SURFACE OF THE GASTRIC PARIETAL-CELLS

  • 1 January 1980
    • journal article
    • research article
    • Vol. 41  (2) , 271-280
Abstract
Viable, intact gastric cells were obtained by pronase digestion of inverted rat stomach. The cell suspensions contained 2 main distinct cell populations, i.e., large cells (mean diameter 16 .mu.m) and small cells (mean diameter 8.5 .mu.m). By indirect immunofluorescence on smears of dispersed rat gastric cells, the large cells were identified as parietal cells, since all the sera containing parietal cell antibodies (PCA) were seen to react with the cytoplasm of these cells, leaving the cytoplasm of the small cells completely unstained. Thirty-one PCA-positive sera and 41 PCA-negative sera were tested for gastric cell surface-reactive antibodies by an indirect immunofluorescence technique on suspensions of viable gastric cells. All the PCA-containing sera yielded a membrane immunofluorescence confined to the large cells, while none of the PCA-negative sera induced this fluorescent pattern. The surface reaction persisted unmodified when F(ab'')2 fragments processed from IgG PCA-positive sera and FITC[fluorescein isothiocyanate]-conjugated pepsin fragments of rabbit IgG directed against the F(ab'')2 fragments of human IgG were employed for the membrane fluorescence studies. The absorption of PCA-positive sera with viable, intact gastric cells led to the disppearance of the surface immunofluoresence of the viable large cells and the cytoplasmic fluorescence of the rat parietal cells. PCA invariably react with an antigen represented on the surface of parietal cells; this antigen is immunologically identical to the intracytoplasmic microsomal antigen.