HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Jerry, L. M. Articles by Kunkel, H. G. Search for Related Content PubMed Articles by Jerry, L. M. Articles by Kunkel, H. G.

The Unique Reassociation of Human IgA2 Immunoglobulins from Dimer Subunits

From The Rockefeller University, New York, New York 10021

Abstract

The Am₂(+) genetic variant of human IgA2 immunoglobulins lacks disulfide bridges between the heavy and light chains. Under dissociating conditions these proteins separate spontaneously into covalent heavy (H₂) and light (L₂) chain dimer subunits. In this study covalent heavy (H₂) and light (L₂) chain dimers were prepared from Am₂(+) IgA2 myeloma proteins. These subunits recombined readily to give molecules which closely resembled the native proteins in hydrodynamic, antigenic and optical properties. In contrast, in the case of IgG, IgA1 and Am₂(-) IgA2 proteins with intact H-L interchain disulfide bridges, covalent heavy and light chain dimers prepared from these proteins failed to recombine, although monomer heavy and light chains recombined readily. Among human immunoglobulins this property of reversible dissociation and reassociation appears to characterize the Am₂(+) genetic variant of IgA2.

The light chains exist within these molecules as disulfide-bonded dimers. Selective cleavage of this inter-light (L-L) chain disulfide bridge was possible by gentle reduction with cysteine, with the inter-heavy (H-H) chain bridges remaining intact.

Footnotes

¹ Present address: Division of Immunochemistry and Allergy, Royal Victoria Hospital, Montreal. Canada.

This article has been cited by other articles:

				M. R. Batten, B. W. Senior, M. Kilian, and J. M. Woof Amino Acid Sequence Requirements in the Hinge of Human Immunoglobulin A1 (IgA1) for Cleavage by Streptococcal IgA1 Proteases Infect. Immun., March 1, 2003; 71(3): 1462 - 1469. [Abstract] [Full Text] [PDF]

				A. Kazin and S Beychok Covalent immunoglobulin assembly in vitro: reactivity of light chain covalent dimers (L2) and blocked light chain monomers Science, February 10, 1978; 199(4329): 688 - 690. [Abstract] [PDF]