Stabilization of the classical pathway C3 convertase C42, by a factor F-42, isolated from serum of patients with systemic lupus erythematosus.

Abstract

Sera from sixteen patients with SLE were investigated for the presence of a factor which would conserve convertase activity on preformed EAClgp 4hu2hu for 30 min at 30 degrees in EDTA. Although such a factor could not be detected readily in the sera, chromatography on DE-52 cellulose yielded fractions appearing as three peaks in one patient and as two peaks in a second patient. These peaks were capable of conserving C42 activity and were designated as F-42. Purification of F-42 from the second peak eluting between 4 and 7 mS on DE-52 was obtained by SP-C50, S-300 and QAE-A50 chromatography. F-42 exhibited charge heterogeneity upon SP-C50 chromatography. On polyacrylamide gel electrophoresis the final material migrated as one band, which coincided with the position of F-42 activity upon eluation from a parallel gel. F-42 had an apparent molecular weight of 150,000 and reacted with anti-IgG in Ouchterlony analysis. Sepharose-bound anti-IgG was capable of neutralizing F-42 activity. The purified material was shown to prolong the half-life (T 1/2) of performed cell-bound C42 in GVB-EDTA at 30 degrees from 5 to 80 min.

• Authors: M R Daha, H M Hazevoet, L A Vanes, A Cats
• Journal: Immunology (Immunology) Vol. 40 Issue 3 Pg. 417-24 (Jul 1980) ISSN: 0019-2805 [Print] England
• PMID: 6903557 (Publication Type: Journal Article)

Chemical References

• Antibodies
• Factor-42
• Immunoglobulin G
• Complement Activating Enzymes
• Complement C3-C5 Convertases

Topics

• Antibodies (isolation & purification, metabolism)
• Complement Activating Enzymes (metabolism)
• Complement C3-C5 Convertases (metabolism)
• Complement Pathway, Classical
• Dose-Response Relationship, Immunologic
• Half-Life
• Hemolysis
• Humans
• Immunoglobulin G (immunology)
• Lupus Erythematosus, Systemic (immunology)
• Molecular Weight