Evidence of IgG-mediated enhancement of the antibody response in vivo without complement activation via the classical pathway

✍ Scribed by Erik J. Wiersma; Masato Nose; Brigitta Heyman

• Publisher: John Wiley and Sons
• Year: 1990
• Tongue: English
• Weight: 514 KB
• Volume: 20
• Category: Article
• ISSN: 0014-2980
• DOI: 10.1002/eji.1830201209

✦ Synopsis

Evidence of IgG-mediated enhancement of the antibody response in vivo without complement activation via the classical pathway*

The complement (C) dependency of IgG-mediated enhancement of the antibody response was investigated by immunizing mice with trinitrophenyl-coupled keyhole limpet hemocyanin (TNP-KLH) and either a C-activating TNP-specific monoclonal IgG2, antibody (Hy-1.2) or a mutant, non-C-activating variant of Hy-1.2 (M12). Hy-1.2 as well as M12 efficiently enhanced the anti-KLH response, although Hy-1.2 was more active. In addition, also a naturally non-C-activating TNP-specific IgGl antibody enhanced the response to TNPcoupled bovine serum albumin. Moreover, C-activating IgG could enhance the antibody response in mice depleted of C3 by treatment with cobra venom factor. These findings suggest that the classical pathway of C activation is not required for IgG-mediated enhancement.