Serological cross-reactivity of murine allo-anti-Ias antibody with the molecule on human antigen-presenting cells.

Murine allo-anti-IaS (A.TL anti-A.TH) antibody cross-reacted with human B-cells and antigen-presenting cells, while the antibody did not cross-react with human T-cells, to be precise, PPD-specific proliferative T-cells. Furthermore, the murine allo-anti-IaS antibody could inhibit the PPD-specific responses of human PBL. Thus, the murine allo-anti-IaS antibody affixes on the Ia-like molecule of human antigen-presenting cells in PPD-specific responses. A genetic mapping study of the serological cross-reactive antibody, by absorbing with the spleen cells from B10.S(9R), A.TH, A.TL and SJL mice in order to determine the specificities for the I subregions of the H-2, revealed that the serological cross-reactivity with human PBL was caused by the anti-I-AS antibody.