Inhibition of specific binding of DNP (dinitrophenyl) determinant to lymphoid-cell receptors by related and unrelated compounds : quantitative studies in vitro.

The effect of related and unrelated compounds on the specific binding of dinitrophenyl-coupled bacteriophage (DNP-T4) to lymphoid cell receptors has been examined and compared with the effect on the neutralization of DNP-T4 by anti-DNP serum. Spleen cells and sera from Balb/c mice immunized with DNP-bovine serum albumin were used. The binding of DNP-T4 to the cells was inhibited by DNP-eAcp, di-DNP-Lys, DNP-Tyr, DNP-p(Ornith) and DNP-BSA (among the DNP-derivatives tested), TNP-BSA, ARS-p(Tyr) and TGA. In addition with the above named DNP and TNP compounds, the DNP-T4neutralization by antiserum was also prevented by DNP-derivatives with either L-cysteic acid, alanine, glutamine or poly-L-glutamic acid, while ARS-p(Tyr) and TGA were not effective. Plain carriers (BSA, HSA, poly-ornithine, polylysine and polyglutaminc acid) and cell-mitogens (ConA, LPS and PPD) had no significant inhibitory effect. The results obtained indicate the occurrence of differences between cell-bound receptors and circulating antibodies in what concerning their specific reaction with the dinitrophenyl determinant.