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Modulation of Ig? is essential for the B cell selection in germinal center.

ABSTRACT: The positive and negative selection of antigen-reactive B cells take place in the germinal center (GC) during an immune responses. However, the precise molecular mechanisms underlying these selection machineries, including the involvement of antigen receptor signaling molecules, remain to be elucidated. We found that expression levels of Ig? and Ig?, which are the essential components of B cell antigen-receptor complex, were differentially regulated in GC B cells and that the expression of Ig? was more prominently down-regulated in a portion of GC B cells. The suppression of Ig? down-regulation reduced the number of GL7(+)GC B cells and the affinity maturation in T-dependent responses was markedly impaired. In addition, the disease phenotypes in autoimmune-prone mice were ameliorated by blocking of Ig? down-regulation. These results suggest that Ig? down-regulation is involved in the normal positive selection in GC and the accumulation of autoreactive B cells in autoimmune-prone mice.

SUBMITTER: Todo K

PROVIDER: S-EPMC4650814 | biostudies-other | 2015

REPOSITORIES: biostudies-other

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Modulation of Igβ is essential for the B cell selection in germinal center.

Todo Kagefumi K Koga Orie O Nishikawa Miwako M Hikida Masaki M

Scientific reports 20150518

The positive and negative selection of antigen-reactive B cells take place in the germinal center (GC) during an immune responses. However, the precise molecular mechanisms underlying these selection machineries, including the involvement of antigen receptor signaling molecules, remain to be elucidated. We found that expression levels of Igα and Igβ, which are the essential components of B cell antigen-receptor complex, were differentially regulated in GC B cells and that the expression of Igβ w ...[more]

PMID: 25980548

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