The IgG Fab (Fragment antigen-binding) fragment is a monovalent proteolytic product of Immunoglobulin G. Each Fab fragment retains the variable domains (VH and VL) responsible for antigen specificity while lacking the Fc-mediated effector functions, enabling targeted antigen neutralization without immune activation. This structural configuration prevents cross-linking-induced precipitation or cellular "patching/capping," making Fab fragments ideal for precise antigen targeting in solution or on cell surfaces.
Diagnostically, Fab fragments enable multiplex immunoassays by preventing Fc-mediated cross-reactivity, facilitating simultaneous detection of multiple antigens in flow cytometry and immunohistochemistry. Their monovalent nature ensures minimal background noise in assays requiring high specificity. Emerging applications include autoimmune disease management, where Fab fragments neutralize autoantibodies while circumventing complement activation. By combining targeted binding with reduced immunogenicity, IgG Fab fragments represent a versatile tool in both clinical and research settings.
Common uses include therapeutics research, immune system research, flow cytometry assays, immunohistochemistry assays.
GHS06, GHS08, GHS09
Danger
H300+H310+H330, H373, H400, H410
12 - Non Combustible Liquids
Acute Tox. 2; Acute Tox. 1; STOT RE2; Aquatic Acute 1; Aquatic Chronic 1
P301+P316, P302+P352, P304+P340, P316, P319, P361+P364, P391, P403+P233, P501