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CD19 and BAFF-R can signal to promote B-cell survival in the absence of Syk.

ABSTRACT: The development and function of B lymphocytes is regulated by numerous signaling pathways, some emanating from the B-cell antigen receptor (BCR). The spleen tyrosine kinase (Syk) plays a central role in the activation of the BCR, but less is known about its contribution to the survival and maintenance of mature B cells. We generated mice with an inducible and B-cell-specific deletion of the Syk gene and found that a considerable fraction of mature Syk-negative B cells can survive in the periphery for an extended time. Syk-negative B cells are defective in BCR, RP105 and CD38 signaling but still respond to an IL-4, anti-CD40, CpG or LPS stimulus. Our in vivo experiments show that Syk-deficient B cells require BAFF receptor and CD19/PI3K signaling for their long-term survival. These studies also shed a new light on the signals regulating the maintenance of the normal mature murine B-cell pool.

SUBMITTER: Hobeika E

PROVIDER: S-EPMC4388600 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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CD19 and BAFF-R can signal to promote B-cell survival in the absence of Syk.

Hobeika Elias E Levit-Zerdoun Ella E Anastasopoulou Vasiliki V Pohlmeyer Roland R Altmeier Simon S Alsadeq Ameera A Dobenecker Marc-Werner MW Pelanda Roberta R Reth Michael M

The EMBO journal 20150128 7

The development and function of B lymphocytes is regulated by numerous signaling pathways, some emanating from the B-cell antigen receptor (BCR). The spleen tyrosine kinase (Syk) plays a central role in the activation of the BCR, but less is known about its contribution to the survival and maintenance of mature B cells. We generated mice with an inducible and B-cell-specific deletion of the Syk gene and found that a considerable fraction of mature Syk-negative B cells can survive in the peripher ...[more]

PMID: 25630702

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