In autoimmune hemolytic anemia (AIHA), autoantibody-mediated complement activation results in C3 deposition on RBCs and possibly the formation of the membrane attack complex cumulating in intravascular hemolysis.1-4 In case of acute signs of tissue hypoxia, life-saving transfusion with RBC units is required. However, recovery of RBC transfusions is inadequate because autoantibodies react with r...

The human hepatoma-derived cell line, HepG2, synthesized and secreted functional complement proteins C1r, C1s, C2, C3, C4, C5, factor B, C1 inhibitor, C3b inactivator, a small amount of C6, and trace amounts of C8; but failed to produce detectable C1q, C7, or C9. Immunochemically, C2, C3, C4, C5, and B were isolated from culture medium as proteins with molecular sizes and subunit structures ide...

Complement activation in human atherosclerotic lesions is indicated by the presence of C5b-9 terminal complexes. By using monoclonal antibodies to the complement C3b receptor (CR1) and the iC3b receptor (CR3), it was observed that approximately 20% of the cells in complicated human carotid lesions express CR1 and CR3 antigens. One to five percent of complement receptor-positive cells stained fo...

The complement system plays a key role in several dermatological diseases. Overactivation, deficiency, or abnormality of the control proteins are often related to a skin disease. Autoimmune mechanisms with autoantibodies and a cytotoxic effect of the complement membrane attack complex on epidermal or vascular cells can cause direct tissue damage and inflammation, e.g., in systemic lupus erythem...

Human C1-esterase inhibitor (C1-INH) is a unique anti-inflammatory multifunctional plasma protein best known for its key role in regulation of the classical complement pathway, contact activation system and intrinsic pathway of coagulation. By sequence homology and mechanism of protease inhibition it belongs to the serine proteinase inhibitor (serpin) superfamily. However, in addition to its in...

The complement system has been increasingly recognized to play a pivotal role in a variety of inflammatory and autoimmune diseases. Consequently, therapeutic modulators of the classical, lectin and alternative pathways of the complement system are currently in pre-clinical and clinical development. Our laboratory has identified a peptide that specifically inhibits the classical and lectin pathw...

Frequent alterations in the structure of the complement component C1 inhibitor gene have been found in patients affected by the common variant of hereditary angioedema, characterized by low plasma levels of C1 inhibitor. This control protein limits the enzymic activity of the first component of complement and of other plasma serine proteases. Sequence comparisons of a 4.6-kilobase-long segment ...

Background For the production of recombinant proteins, a human cell-derived expression technology can offer significant advantages with respect to protein quality, serum halflife and safety. High volumetric productivity with firstclass quality is the ultimate ambition during process development. CEVEC’s proprietary expression system based on human amniocytes offers significant advantages for th...

p p t ngioedema is a pathologic condition first described y Quincke and Osler. It can be genetically deterined or acquired, and it is caused by a vascular eaction induced by deficiency or functional altertion of the C1 inhibitor (C1-INH), an enzyme inolved in the regulation of complement, contact, firinolytic, and coagulation systems. Two forms of angioedema have been described in he literature...

Anaphylaxis is a life-threatening allergic reaction. It is triggered by the release of pro-inflammatory cytokines and mediators from mast cells and basophils in response to immunologic or non-immunologic mechanisms. Mediators that are released upon mast cell activation include the highly sulfated polysaccharide and inorganic polymer heparin and polyphosphate (polyP), respectively. Heparin and p...