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

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Barreto, V. Articles by Cumano, A. Search for Related Content PubMed PubMed Citation Articles by Barreto, V. Articles by Cumano, A.

Mice Triallelic for the Ig Heavy Chain Locus: Implications for V_HDJ_H Recombination¹

Unité du Développement des Lymphocytes, Institut Pasteur, Paris, France

V_HDJ_H recombination has been extensively studied in mice carrying an Ig heavy chain rearranged transgene. In most models, inhibition of endogenous Ig rearrangement occurs, consistently with the feedback model of IgH recombination. Nonetheless, an incomplete IgH allelic exclusion is a recurrent observation in these animals. Furthermore, transgene expression in ontogeny is likely to start before somatic recombination, thus limiting the use of Ig-transgenic mice to access the dynamics of V_HDJ_H recombination. As an alternative approach, we challenged the regulation of somatic recombination with the introduction of an extra IgH locus in germline configuration. This was achieved by reconstitution of RAG2^-/- mice with fetal liver cells trisomic for chromosome 12 (Ts12). We found that all three alleles can recombine and that the ratio of Ig allotype-expressing B cells follows the allotypic ratio in trisomic cells. Although these cells are able to rearrange the three alleles, the levels of Ig phenotypic allelic exclusion are not altered when compared with euploid cells. Likewise, we find that most VDJ rearrangements of the silenced allele are unable to encode a functional µ-chain, indicating that the majority of these cells are also genetically excluded. These results provide additional support for the feedback model of allelic exclusion.

This article has been cited by other articles:

				G. Kalmanovich and R. Mehr Models for Antigen Receptor Gene Rearrangement. III. Heavy and Light Chain Allelic Exclusion J. Immunol., January 1, 2003; 170(1): 182 - 193. [Abstract] [Full Text] [PDF]