Production, binding characteristics, and immunogenicity of heterologous anti-idiotypic antibody to herpes simplex virus glycoprotein C

A monoclonal antibody specific for glycoprotein C (gC) of herpes simplex virus type 1 (HSV-1) was used to prepare a heterologous anti-idiotypic antibody in rabbits. After absorption with normal mouse immunoglobulin (NMS) the anti-idiotypic (anti-id) antibody retained binding activity for MoAb D4.1, the immunogen. The anti-id (anti-id C) also demonstrated a cross-reactive binding activity, as shown by ELISA, for MoAb D4.2 and MoAb D4.8 which was specific for glycoprotein D (gD) and glycoprotein B (gB) of HSV-1, respectively. Also, anti-id C bound to and eluted from MoAb D4.2 and MoAb D4.8 affinity columns retained the ability to bind all three monoclonal antibodies. This cross-reactive anti-id could inhibit the binding of each of the three monoclonal antibodies to their respective proteins, suggesting an antigen combining site specificity. Subsequently, the idiotope on MoAb D4.8 was shown to be outside the antigen combining site, since anti-id C recognized MoAb D4.8 complexed with gB. The anti-id, however, did not bind MoAb D4.1 or MoAb D4.2, if these monoclonals were bound to gC or gD, respectively, suggesting the cross-reactive determinant was paratopic on those two monoclonals. Immunization of mice with anti-id C could prime splenocytes in vivo to proliferate in response to HSV antigen stimulation in vitro. Thus, spleen cells involved in the HSV immune response in vitro recognized the anti-idiotypic antibody in vivo.