The Journal of Immunology, Vol 157, Issue 3 1297-1305, Copyright © 1996 by American Association of Immunologists

ARTICLES

Murine glomerulotropic monoclonal antibodies are highly oligoclonal and exhibit distinctive molecular features

JB Lefkowith, R Di Valerio, J Norris, GD Glick, AL Alexander, L Jackson and GS Gilkeson
Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA.

We recently produced a panel of seven glomerular-binding mAbs from a nephritic MRL-lpr mouse that bind to histones/nucleosomes (group I) or DNA (group II) adherent to glomerular basement membrane. To elucidate the molecular basis of their binding and ontogeny, we sequenced their variable (V) regions, analyzed the apparent somatic mutations, and predicted their three-dimensional structures. There were two clonally related sets (3 of 4 in group I, 3 of 3 in group II) both of the VHJ1558 family, and one mAb of the VH 7183 family. V region somatic mutations within clonally related sets had little effect on glomerular binding and did not appear to be selected for based on glomerular binding. The VH regions were most homologous with those from autoantibodies to histones, DNA, or IgG (i.e., rheumatoid factors), the Vkappa regions, with those from autoantibodies to small nuclear ribonucleoproteins (snRNP). The VH regions also exhibited an unusual VD junction (in the group I clonally related set) and an overall high content of charged amino acids (arginine, aspartic acid) in complementarity-determining regions (CDRs), particularly in CDR3. Molecular modeling studies suggested that the Fv regions of these mAbs converge to form a flat, open surface with a net positive charge. The CDR arginines in group I mAbs; appear to be located in Ag contact regions of the binding cleft. In sum, these data suggest that glomerulotropic mAbs are a highly restricted set of Abs with distinctive molecular features that may mediate their binding to glomeruli.

This article has been cited by other articles:

				H. Sekine, H. Watanabe, and G. S. Gilkeson Enrichment of Anti-Glomerular Antigen Antibody-Producing Cells in the Kidneys of MRL/MpJ-Faslpr Mice J. Immunol., March 15, 2004; 172(6): 3913 - 3921. [Abstract] [Full Text] [PDF]

				Z. Liang, C. Xie, C. Chen, D. Kreska, K. Hsu, L. Li, X. J. Zhou, and C. Mohan Pathogenic Profiles and Molecular Signatures of Antinuclear Autoantibodies Rescued from NZM2410 Lupus Mice J. Exp. Med., February 2, 2004; 199(3): 381 - 398. [Abstract] [Full Text] [PDF]

				Z. Liang, C. Chen, and C. Mohan Molecular Signatures of Anti-nuclear Antibodies: Contributions of Specific Light Chain Residues and a Novel New Zealand Black V{kappa}1 Germline Gene J. Immunol., October 1, 2003; 171(7): 3886 - 3894. [Abstract] [Full Text] [PDF]

				L E Schiffer, N Hussain, X Wang, W Huang, J Sinha, M Ramanujam, and A Davidson Lowering anti-dsDNA antibodies--what's new? Lupus, December 1, 2002; 11(12): 885 - 894. [Abstract] [PDF]