Zebrafish B Cell Development without a Pre-B Cell Stage, Revealed by CD79 Fluorescence Reporter Transgenes.
J Immunol
; 199(5): 1706-1715, 2017 09 01.
Article
em En
| MEDLINE
| ID: mdl-28739882
ABSTRACT
CD79a and CD79b proteins associate with Ig receptors as integral signaling components of the B cell Ag receptor complex. To study B cell development in zebrafish, we isolated orthologs of these genes and performed in situ hybridization, finding that their expression colocalized with IgH-µ in the kidney, which is the site of B cell development. CD79 transgenic lines were made by linking the promoter and upstream regulatory segments of CD79a and CD79b to enhanced GFP to identify B cells, as demonstrated by PCR analysis of IgH-µ expression in sorted cells. We crossed these CD79-GFP lines to a recombination activating gene (Rag)2mCherry transgenic line to identify B cell development stages in kidney marrow. Initiation of CD79GFP expression in Rag2mCherry+ cells and the timing of Ig H and L chain expression revealed simultaneous expression of both IgH-µ- and IgL-κ-chains, without progressing through the stage of IgH-µ-chain alone. Rag2mCherry+ cells without CD79GFP showed the highest Rag1 and Rag2 mRNAs compared with CD79a and CD79bGFP+ B cells, which showed strongly reduced Rag mRNAs. Thus, B cell development in zebrafish does not go through a Raghi CD79+IgH-µ+ pre-B cell stage, different from mammals. After the generation of CD79GFP+ B cells, decreased CD79 expression occurred upon differentiation to Ig secretion, as detected by alteration from membrane to secreted IgH-µ exon usage, similar to in mammals. This confirmed a conserved role for CD79 in B cell development and differentiation, without the requirement of a pre-B cell stage in zebrafish.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Peixe-Zebra
/
Linfócitos B
/
Proteínas de Peixes
/
Antígenos CD79
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Células Precursoras de Linfócitos B
/
Rim
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
J Immunol
Ano de publicação:
2017
Tipo de documento:
Article