Factor H Depleted Sera

Normal human serum was depleted of factor H by immunoaffinity chromatography. The product is tested for the absence of factor H by double immunodiffusion. Factor H is a regulator of complement activation. As a result, factor H-Dpl is still capable of activating the alternative pathway and does so spontaneously and very rapidly in the absence of factor H. In fact, activation occurs in less than 2 min in the fluid phase without an activating particle resulting in the consumption of both C3 and factor B. For this reason this depleted serum is stored with 0.1 mM EDTA to inhibit spontaneous activation.