ABSTRACT
Cobra venom factor (CVF) is the complement-activating protein in cobra venom. Not a toxin itself, CVF facilitates the entry of venom toxins into the bloodstream of the prey through massive activation of complement at the envenomation site. This chapter reviews the structure of CVF, how it interacts with the complement system, the structural and functional homology to complement component C3, and the use of CVF as an experimental tool to decomplement laboratory animals in order to study the functions of complement in host defense and immune response as well as in the pathogenesis of diseases. This chapter also describes progress in exploiting the homology between CVF and C3 as a tool to study the structure–function relationship between these proteins. Also reviewed are human C3 derivatives with the complement-depleting function of CVF. These human C3 derivatives, referred to as humanized CVF, represent a novel therapeutic concept for diseases with complement pathology. The use of humanized CVF for therapeutic complement depletion in several preclinical models of human diseases is described.
