Somatic diversification in the absence of antigen-driven responses is the hallmark of the IgM+ IgD+ CD27+ B cell repertoire in infants.
J Exp Med
; 205(6): 1331-42, 2008 Jun 09.
Article
in En
| MEDLINE
| ID: mdl-18519648
ABSTRACT
T cell-dependent immune responses develop soon after birth, whereas it takes 2 yr for humans to develop T cell-independent responses. We used this dissociation to analyze the repertoire diversification of IgM(+)IgD(+)CD27(+) B cells (also known as "IgM memory" B cells), comparing these cells with switched B cells in children <2 yr of age, with the aim of determining whether these two subsets are developmentally related. We show that the repertoire of IgM(+)IgD(+)CD27(+) B cells in the spleen and blood displays no sign of antigen-driven activation and expansion on H-CDR3 spectratyping, despite the many antigenic challenges provided by childhood vaccinations. This repertoire differed markedly from those of switched B cells and splenic germinal center B cells, even at the early stage of differentiation associated with mu heavy chain expression. These data provide evidence for the developmental diversification of IgM(+)IgD(+)CD27(+) B cells, at least in very young children, outside of T cell-dependent and -independent immune responses.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Genetic Variation
/
Immunoglobulin D
/
Immunoglobulin M
/
B-Lymphocytes
/
Tumor Necrosis Factor Receptor Superfamily, Member 7
Limits:
Humans
/
Infant
Language:
En
Journal:
J Exp Med
Year:
2008
Type:
Article
Affiliation country:
France