Immunoglobulin G2a (IgG2a)

Immunoglobulin G2a (IgG2a) is a mouse-specific antibody subclass that serves as a primary mediator of the Th1-type immune response. It is functionally distinguished by its high affinity for activating Fc gamma receptors (such as FcγRI and FcγRIV) and its superior ability to fix complement, making it highly effective at promoting antibody-dependent cellular cytotoxicity (ADCC) and phagocytosis. In preclinical research, the production of IgG2a is widely used as a biomarker to assess the skewing of the immune system toward a Th1 profile, particularly in response to vaccines or immunomodulatory adjuvants like CpG. While IgG2a is exclusive to rodents, human IgG1 is considered its functional ortholog due to shared effector capabilities. Modulating the production of this isotype, typically through cytokines like Interferon-gamma (inducer) or Interleukin-4 (inhibitor), is a common strategy in murine models to study treatments for cancer, viral infections, and autoimmune diseases.

Other names

IgG2aMouse IgG2aIgh-1Ighg2aImmunoglobulin gamma-2A heavy chain

Modulated through cytokine-driven class switch recombination (CSR) in B lymphocytes, where IFN-gamma induces Ighg2a germline transcription while IL-4 antagonizes this process.