Pre-treatment of syngeneic mice with polyclonal populations of Protein-A separated anti-idiotypic antibodies prepared against anti-CVB3 viral idiotypes resulted in reduction of inflammatory myocarditis in virus-challenged mice. Cellular immunity as assessed by cell-migration-inhibition resulted in specific cell-mediated sensitivity against anti-Ids (CVB3) as well as viral preparations. Animals pre-treated with anti-idiotypic preparations developed an anamnestic anti-viral antibody response, with antibodies capable of specifically binding CVB3 virus antigen in an ELISA assay; but without CVB3 viral neutralizing capability. Adoptive transfer of limited numbers of syngeneic anti-Id immunized lymphoid cell populations failed to alter the course of inflammatory myocarditis in CVB3 virus-challenged animals. Cellular binding studies utilizing anti-Ids suggested increased, but nonspecific binding of anti-Ids to lymphoid and myocyte populations in CVB3 infected animals. The data suggest an immunomodulatory role of idiotype-anti-idiotype interactions in the development of myocarditis.

Investigation into the mechanism(s) whereby monocytes-macrophages are mobilized to the myocardium of coxsackievirus (CVB3)-infected mice was approached by assessing the role of anti-idiotypic antibodies against specific antiviral IgG molecules. Balb/c mice preinoculated with polyclonal anti-idiotypic, syngeneic antibodies resulted in significantly decreased myocarditis after virus challenge. On the other hand, oil-induced peritoneal exudate cells obtained from virus-exposed animals demonstrated increased chemotaxis in the presence of polyclonal anti-Id preparations, whereas peritoneal exudate cells from normal animals did not. Specificity of the anti-Ids as confirmed by the binding of the syngeneic anti-anti-idiotypic antibodies (antibody 3) to solubilized viral antigen(s) and Fab fragments prepared from the anti-idiotypic antibodies. Paradoxic biological effects of anti-Id, demonstrated in vitro and in vivo, suggest possible and subtle immunoregulation of the macrophage effector arm by anti-idiotypes during the course of virus infection.

A monoclonal anti-idiotypic antibody (anti-Id), produced by electrofusion and designated anti-1d88, was able to modulate expression of murine autoimmune myocarditis mediated by coxsackievirus B3 (CVB3). The anti-Id was characterized as an immunoglobulin G2b species possessing K light chains and was able to reduce expression of inflammatory myocarditis in anti-Id-pretreated mice challenged with CVB3. Anti-Id88 was able to stimulate specific cell-mediated immunity against anti-ld88, as well as CVB3, and exerted a suppressive effect on the proliferation of mixed spleen cell populations from virus-exposed mice. Anti-Id stimulated an anti-anti-Id antibody 3 population able to bind antibody 2 F(ab')2 fragments or virus antigen in an indirect enzyme-linked immunosorbent assay. Western blot (immunoblot) analysis of anti-Id88 exhibited binding of syngeneic anti-Id antibody to idiotypes present on immunoglobulin G molecules from virus-immunized mice.

Mice infected with coxsackievirus B develop immunologically mediated inflammatory myocarditis in heart tissue that results in the development of autoantibodies with multiple idiotypes. The specificity and temporal development of autoantibodies produced during coxsackievirus B3 infection were assessed. Antiviral idiotypes and anti-idiotypic antibodies against coxsackievirus B3 idiotypes were detected and quantitated over 21-and 42-day periods, respectively. Both polyclonal and monoclonal anti-idiotypes exhibited greater but nonspecific binding to heart, liver, kidney, and spleen cells from virus-exposed animals and normal tissue. Binding of anti-idiotypes was also demonstrated to myosin and to solubilized heart-associated antigens but not to virus. Western immunoblot analysis revealed that monoclonal and polyclonal anti-idiotypes selectively bound to hypertonic, salt-extracted, solubilized proteins of myocyte extracts of virus-exposed animals.

Polyclonal anti-idiotypic antibodies (anti-Ids)(fim) developed against idiotypes on antibodies (Ab-1s) that specifically bind structural, organelle fimbrial proteins of Escherichia coli were able to modulate immune function in anti-Id(fim)-immunized mice. Proliferation or suppression of splenic lymphoid cell responses by polyclonal anti-Ids in tissue culture appeared to be dose dependent. Anti-Ids were able to induce a dose-dependent T-cell-mediated immunity specific for type 1 fimbrial antigen(s) in immunized animals when assessed in vitro, but they failed to elicit in vivo positive ear-swelling skin reactions. Anti-Ids were unable to induce protective immunity against an in vivo infectious challenge with E. coli in anti-Id-immunized adult animals, but they stimulated a specific, secondary antibody response in anti-Id-challenged mice. Anti-Ids stimulated the development of anti-anti-Ids (Ab-3s) specifically binding a fimbrial antigen(s) and revealed the presence of antibody idiotypes binding E. coli adhesin proteins in the 27-to 29-kilodalton range. Results suggest discrete, but subtle, immunomodulatory effects of the anti-Ids and potential vaccinoid properties capable of stimulating a specific humoral and cellular response in vivo.