SPATIAL ARRANGEMENT OF H-2 SPECIFICITIES: EVIDENCE FROM ANTIBODY ADSORPTION AND KINETIC STUDIES

Abstract

SUMMARY H-2 isoantisera were adsorbed on to the surface of mouse lymphocytes and were shown to inhibit to varying degrees the subsequent adsorption of non-crossreacting H-2 isoantisera. Mutual inhibition of adsorption of two isoantisera onto the lymphocyte was also demonstrated in kinetic experiments. The suggested explanation for the observations is that H-2 isoantigenic sites of different specificity are sufficiently close together on the surface of the cell that the presence of the first type of antibody sterically inhibits the adsorption of the second. The effect was demonstrated with IgG fractions of antisera in one case, suggesting that the spacing of the sites is less than or equal to the size of an IgG molecule.