What is Borrelia burgdorferi IgG Antibody by Western Blot?
IgG class antibodies to B. burgdorferi develop 4–6 weeks following infection as the humoral immune response matures beyond the initial IgM phase. In Western Blot format, denatured B. burgdorferi proteins are separated by molecular weight on polyacrylamide gel, transferred to nitrocellulose membrane, and probed with patient serum — reactive bands appear at positions corresponding to the molecular weights of the antigenic proteins to which the patient has generated antibodies. Persistence of IgG reactivity is typical following treated and untreated Lyme disease and does not independently indicate ongoing active infection.