Description
Background: Complement factor D (CFD) is also known as Adipsin, C3 convertase activator and Properdin factor D (PFD), which contains one peptidase S1 domain and belongs to the peptidase S1 family. CFD cleaves factor B when the latter is complexed with factor C3b, activating the C3bbb complex, which then becomes the C3 convertase of the alternate pathway. CFD is a serine protease that stimulates glucose transport for triglyceride accumulation in fats cells and inhibits lipolysis. Defects in CFD are the cause of complement factor D deficiency which predisposes to invasive meningococcal disease.
Principle of the Assay: This kit was based on sandwich enzyme-linked immune-sorbent assay technology. Anti CFD antibody was precoated onto the 96-well plate. The biotin conjugated anti CFD antibody was used as the detection antibody. The standards and pilot samples were added to the wells subsequently. After incubation, unbound conjugates were removed by wash buffer. Then, biotinylated detection antibody was added to bind with CFD conjugated on coated antibody. After washing off unbound conjugates, HRP-Streptavidin was added. After a third washing, TMB substrates were added to visualize HRP enzymatic reaction. TMB was catalyzed by HRP to produce a blue color product that turned yellow after adding a stop solution. Read the O.D. absorbance at 450nm in a microplate reader. The concentration of CFD in the sample was calculated by drawing a standard curve. The concentration of the target substance is proportional to the OD450 value