Le CD40 signals mature B10pro cells to B10 cells, BCR cross-linking inhibits this process (20). Thus, although visualization of immune cells actively producing IL-10 in vivo remains a difficult task, these ex vivo assays to characterize IL-10 competence have shed light on the small subset of B cells that have Crotaline msds turned on the IL-10 functional program and are capable of producing this potent regulatory cytokine. B10 cell distribution in vivo The spleen is the predominant reservoir of B10 cells in mice (20). However, mouse B10 cells have also been identified in the gut-associated lymphoid DuvoglustatMedChemExpress 1-Deoxynojirimycin tissues, such as the mesenteric lymph nodes and peritoneal cavity, as well as in the peripheral blood and lymph nodes (4, 20, 24). The peritoneal cavity also contains substantial frequencies of B10 and B10pro cells. The greatest frequencies of B10 cells in the peritoneal cavity were identified within the CD5+ CD11b+ B1a B cell subset (38 ), followed by the CD5- CD11b+ B1b (18 ) and the CD5- CD11b- B2 (4 ) subsets. Peritoneal cavity B cells also contain substantial proportions of B10pro cells, as 48 h CD40 mAb with 5 h L+PIM stimulation increases IL-10+ B-cell frequencies within the B1a, B1b, and B2 subsets to 41 , 22 , and 6 , respectively. Although the overall peritoneal cavity B-cell compartment contains the greatest frequency of B10 cells, the significantly reduced number of total B cells in the peritonealNIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author ManuscriptImmunol Rev. Author manuscript; available in PMC 2015 May 01.Candando et al.Pagecavity as compared to the spleen results in a greater overall number of B10 cells in the spleen. Within other mucosal tissues, B10 cells represent approximately 1 of mesenteric lymph nodes, 4 of lamina propia, and 3 of Peyer’s patch B cells. Additionally, few, if any, B10 cells are present in the peripheral blood and lymph nodes, though 3? of peripheral blood and lymph node B cells are B10pro cells (20). Thus, B10 and B10pro cells are rare within the blood, peripheral lymph nodes, and gut-associated lymphoid tissues, with the exception of the peritoneal cavity, where IL-10+ cells represent a substantial portion of the local B-cell pool. B10 cell phenotype L+PIM stimulation for 5 h does not change the expression of most cell surface molecules, particularly in the presence of monensin, which allows for the characterization of the in vivo B10 cell phenotype (20). An extensive cell surface phenotyping study revealed that mouse spleen B10 cells are IgMhi IgDlo CD19hi MHC-IIhi CD21int/high CD23lo CD24hi CD43+/- CD93-. Additionally, spleen B10 cells are predominantly enriched (15?0 ) within the CD1dhi CD5+ subset, as are B10pro cells. However, this designation should not be interpreted as a definitive phenotype for B10 cells, but rather as a feasible means to enrich these cells for functional studies without having to stimulate the cells with L+PIM to induce IL-10 expression (17). Spleen and peritoneal cavity B10 cells have similar phenotypic profiles with notable exceptions. As in the spleen, peritoneal cavity B10 cells express high levels of IgM, CD5, CD19, CD24, CD43, and MHC class II (MHC-II) and low levels of IgD and CD23 relative to their non-B10 cell counterparts (24). However, the CD1dhi CD5+ phenotype cannot be used to enrich peritoneal cavity B cells for B10 cells because high-level CD1d expression is not induced within the peritoneal cavity (17). Furthermore, CD5 expression in this compartment.Le CD40 signals mature B10pro cells to B10 cells, BCR cross-linking inhibits this process (20). Thus, although visualization of immune cells actively producing IL-10 in vivo remains a difficult task, these ex vivo assays to characterize IL-10 competence have shed light on the small subset of B cells that have turned on the IL-10 functional program and are capable of producing this potent regulatory cytokine. B10 cell distribution in vivo The spleen is the predominant reservoir of B10 cells in mice (20). However, mouse B10 cells have also been identified in the gut-associated lymphoid tissues, such as the mesenteric lymph nodes and peritoneal cavity, as well as in the peripheral blood and lymph nodes (4, 20, 24). The peritoneal cavity also contains substantial frequencies of B10 and B10pro cells. The greatest frequencies of B10 cells in the peritoneal cavity were identified within the CD5+ CD11b+ B1a B cell subset (38 ), followed by the CD5- CD11b+ B1b (18 ) and the CD5- CD11b- B2 (4 ) subsets. Peritoneal cavity B cells also contain substantial proportions of B10pro cells, as 48 h CD40 mAb with 5 h L+PIM stimulation increases IL-10+ B-cell frequencies within the B1a, B1b, and B2 subsets to 41 , 22 , and 6 , respectively. Although the overall peritoneal cavity B-cell compartment contains the greatest frequency of B10 cells, the significantly reduced number of total B cells in the peritonealNIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author ManuscriptImmunol Rev. Author manuscript; available in PMC 2015 May 01.Candando et al.Pagecavity as compared to the spleen results in a greater overall number of B10 cells in the spleen. Within other mucosal tissues, B10 cells represent approximately 1 of mesenteric lymph nodes, 4 of lamina propia, and 3 of Peyer’s patch B cells. Additionally, few, if any, B10 cells are present in the peripheral blood and lymph nodes, though 3? of peripheral blood and lymph node B cells are B10pro cells (20). Thus, B10 and B10pro cells are rare within the blood, peripheral lymph nodes, and gut-associated lymphoid tissues, with the exception of the peritoneal cavity, where IL-10+ cells represent a substantial portion of the local B-cell pool. B10 cell phenotype L+PIM stimulation for 5 h does not change the expression of most cell surface molecules, particularly in the presence of monensin, which allows for the characterization of the in vivo B10 cell phenotype (20). An extensive cell surface phenotyping study revealed that mouse spleen B10 cells are IgMhi IgDlo CD19hi MHC-IIhi CD21int/high CD23lo CD24hi CD43+/- CD93-. Additionally, spleen B10 cells are predominantly enriched (15?0 ) within the CD1dhi CD5+ subset, as are B10pro cells. However, this designation should not be interpreted as a definitive phenotype for B10 cells, but rather as a feasible means to enrich these cells for functional studies without having to stimulate the cells with L+PIM to induce IL-10 expression (17). Spleen and peritoneal cavity B10 cells have similar phenotypic profiles with notable exceptions. As in the spleen, peritoneal cavity B10 cells express high levels of IgM, CD5, CD19, CD24, CD43, and MHC class II (MHC-II) and low levels of IgD and CD23 relative to their non-B10 cell counterparts (24). However, the CD1dhi CD5+ phenotype cannot be used to enrich peritoneal cavity B cells for B10 cells because high-level CD1d expression is not induced within the peritoneal cavity (17). Furthermore, CD5 expression in this compartment.
