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The development of mature B lymphocytes requires the combined function of CD19 and the p110? subunit of PI3K.

ABSTRACT: Mice lacking either CD19 or p110? have reduced numbers of marginal zone and B1 B cells but normal numbers of naïve B2 cells which occupy the follicles of the lymphoid organs. We show here that mice lacking both CD19 and p110? have normal B cell development in the bone marrow but have a significant reduction in the number of naïve B2 cells in the bone marrow, spleen and lymph nodes. These p110?/CD19 double mutant B cells show a survival defect and reduced responsiveness to the pro-survival cytokine BAFF despite normal NF?B2/p100 processing and elevated expression of Bcl-2. Although the combined loss of p110? and CD19 did not increase switching to Ig-lambda in immature B cells, mature B lymphocytes from the lymph nodes of p110?/CD19 double mutant mice express highly elevated levels of mRNA encoding RAG-1 and RAG-2, which confirms the existing synergy between CD19 and p110?-mediated signaling.

SUBMITTER: Kovesdi D

PROVIDER: S-EPMC3065673 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature

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The development of mature B lymphocytes requires the combined function of CD19 and the p110δ subunit of PI3K.

Kövesdi Dorottya D Bell Sarah E SE Turner Martin M

Self/nonself 20100311 2

Mice lacking either CD19 or p110δ have reduced numbers of marginal zone and B1 B cells but normal numbers of naïve B2 cells which occupy the follicles of the lymphoid organs. We show here that mice lacking both CD19 and p110δ have normal B cell development in the bone marrow but have a significant reduction in the number of naïve B2 cells in the bone marrow, spleen and lymph nodes. These p110δ/CD19 double mutant B cells show a survival defect and reduced responsiveness to the pro-survival cytoki ...[more]

PMID: 21487516

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