The complement cascade of the immune system is an important mediator of the inflammatory response to infection; however it is crucial that this pathway is tightly regulated to prevent uncontrolled activation, which can lead to damage to host tissues. The complement system has many regulators that control activation; both membrane-bound and soluble factors. This review will focus on what is currently known about the transcriptional regulation of the soluble complement regulatory genes C1-inhibitor, complement factor I, complement factor H and C4-binding protein. The absence or mutation of these regulators is all associated with specific disease, and yet their contribution to disease is often poorly understood. It is through full understanding of these genes that we can comprehend the diseases with which they are implicated, and thus prove why knowledge of the transcriptional regulation of these genes is valuable.
