Comparison of bovine IgG1, IgG2 and IgM for ability to promote killing of Mycoplasma bovis by bovine alveolar macrophages and neutrophils.

The IgG1, IgG2 and IgM fractions were purified by chromatography from bovine antisera to Mycoplasma bovis. They were assayed for specific antibody and compared for ability to promote killing of M. bovis by bovine peripheral-blood neutrophils and alveolar macrophages. None of the Ig preparations killed the mycoplasma in the absence of the cells. The IgG1 and IgG2 preparations both promoted mycoplasma killing by the macrophages; IgM appeared to have no effect. The IgG2 preparation promoted killing by the neutrophils but neither the IgG1 or IgM fraction appeared effective.