IgG2C

IgG2c is a mouse IgG subclass present in C57BL/6, NOD, and related laboratory strains, where it occupies the locus held by IgG2a in BALB/c-type genomes, so the two genes are essentially strain-specific allelic variants rather than independent subclasses. Like IgG2a, IgG2c supports Th1-type humoral responses and binds activating Fc gamma receptors including Fc gamma RIV, mediating strong effector functions in models of infection and autoimmunity. IgG2c antibodies predominate in lupus-prone mice and contribute to glomerulonephritis pathogenesis. Researchers must account for the IgG2a-versus-IgG2c strain difference when choosing isotype controls, assay reagents, and Fc engineering strategies in murine studies.