Changes in Plasma Complement C4 and Factor B Allotypes after Liver Transplantation

Abstract

Plasma complement allotypes for C4 and factor B were determined in 21 patients before and after liver transplantation together with donor typing. In 17 transplantations allelic differences between the patient and the donor could be shown. In all cases the patient’s C4 and factor-B types converted to that of the donor, showing that the liver is the major source of plasma complement C4 and factor B.

Inhibition of the alternative complement pathway by antisense oligonucleotides targeting complement factor B improves lupus nephritis in mice

“…1A). Since the liver is the major contributor to circulating FB protein levels (Koskimies et al 1991;Morgan and Gasque 1997;Marsh et al 2001), we measured the level of plasma FB protein and, as expected, dose dependent reductions in hepatic mRNA corresponded well with the reduction in plasma factor B levels as quantified by western blot (Fig. 1B).…”

“…This activation promotes pro-inflammatory mechanisms by the generation of the chemotactic factor C5a (Sterner et al, 2014). FB is predominantly produced by hepatocytes and secreted into blood, (Koskimies et al, 1991;Morgan and Gasque, 1997;Marsh et al, 2001) although several other cell types can also produce FB (Ripoche et al, 1988;Strunk et al, 1988;Whaley, 1980). The hepatocyte FB is an acute phase reactant; therefore, serum levels of FB increase during inflammation stimulated by cytokines, growth factors, and bacterial products.…”

Adeno-Associated Virus Vector Gene Delivery Elevates Factor I Levels and Downregulates the Complement Alternative PathwayIn Vivo

“…In contrast, serum levels of CFB were elevated in AAV.CFI treated animals (Figure 4D, Supplementary Figure 4). The higher levels of CFB were not attributed to enhanced transcriptional activity from the CFB gene in the liver, which is the predominant source of the protein [26], as mRNA levels remained unchanged in control and test animals (Figure 4E).…”