TY - JOUR
T1 - Cd1d regulates B cell development but not B cell accumulation and IL10 production in mice with pathologic CD5+ B cell expansion
AU - Palmer, Victoria L.
AU - Nganga, Vincent K.
AU - Rothermund, Mary E.
AU - Perry, Greg A.
AU - Swanson, Patrick C.
N1 - Funding Information:
This work was supported by a grant from the Nebraska LB595 Cancer and Smoking Disease Research Program (to PCS). The National Center for Research Resources provided support for research laboratory construction (C06 RR17417-01) and the Creighton University Animal Resource Facility (G20RR024001). We acknowledge the NIH Tetramer Core Facility (contract HHSN272201300006C) for providing loaded and unloaded CD1d tetramers for flow cytometric analysis, and Creighton University Flow Cytometry Core Facility for providing flow cytometry services. This publication’s contents are the sole responsibility of the authors and do not necessarily represent the official views of the NIH.
Publisher Copyright:
© 2015 Palmer et al.
PY - 2015/11/4
Y1 - 2015/11/4
N2 - Background: CD1d is a widely expressed lipid antigen presenting molecule required for CD1d-restricted invariant natural killer T (iNKT) cell development. Elevated CD1d expression is detected in CD5+ IL10-producing B cells, called B10 B cells, and is correlated with poorer prognosis in chronic lymphocytic leukemia (CLL), a CD5+ B cell malignancy with B10-like functional properties. Whether CD1d expression regulates CD5+ B cell accumulation, IL10 competence, and antibody production in naïve mice with pathologic CD5+ B cell expansion remains untested. Results: Using three different transgenic mouse models of benign or leukemic CD5+ B cell expansion, we found that CD1d was differentially expressed on CD5+ B cells between the three models, but loss of CD1d expression had no effect on CD5+ B cell abundance or inducible IL10 expression in any of the models. Interestingly, in the CLL-prone Eμ-TCL1 model, loss of CD1d expression suppressed spontaneous IgG (but not IgM) production, whereas in the dnRAG1xEμ-TCL1 (DTG) model of accelerated CLL, loss of CD1d expression was associated with elevated numbers of splenic CD4+ and CD8+ T cells and an inverted CD4+:CD8+ T cell ratio. Unexpectedly, before leukemia onset, all three transgenic CD1d-deficient mouse strains had fewer splenic transitional B cells than their CD1d-proficient counterparts. Conclusions: The results show that CD1d expression and iNKT cells are dispensable for the development, accumulation, or IL10 competence of CD5+ B cells in mice prone to benign or leukemic CLL-like B cell expansion, but reveal a novel role for iNKT cells in supporting B cell progression through the transitional stage of development in these animals. These results suggest CD1d-directed therapies to target CLL could be evaded by downregulating CD1d expression with little effect on continued leukemic CD5+ B cell survival. The data also imply that iNKT cells help restrain pro-leukemic CD8+ T cell expansion in CLL, potentially explaining a reported correlation in human CLL between disease progression, the loss of NKT cells, and a paradoxical increase in CD8+ T cells.
AB - Background: CD1d is a widely expressed lipid antigen presenting molecule required for CD1d-restricted invariant natural killer T (iNKT) cell development. Elevated CD1d expression is detected in CD5+ IL10-producing B cells, called B10 B cells, and is correlated with poorer prognosis in chronic lymphocytic leukemia (CLL), a CD5+ B cell malignancy with B10-like functional properties. Whether CD1d expression regulates CD5+ B cell accumulation, IL10 competence, and antibody production in naïve mice with pathologic CD5+ B cell expansion remains untested. Results: Using three different transgenic mouse models of benign or leukemic CD5+ B cell expansion, we found that CD1d was differentially expressed on CD5+ B cells between the three models, but loss of CD1d expression had no effect on CD5+ B cell abundance or inducible IL10 expression in any of the models. Interestingly, in the CLL-prone Eμ-TCL1 model, loss of CD1d expression suppressed spontaneous IgG (but not IgM) production, whereas in the dnRAG1xEμ-TCL1 (DTG) model of accelerated CLL, loss of CD1d expression was associated with elevated numbers of splenic CD4+ and CD8+ T cells and an inverted CD4+:CD8+ T cell ratio. Unexpectedly, before leukemia onset, all three transgenic CD1d-deficient mouse strains had fewer splenic transitional B cells than their CD1d-proficient counterparts. Conclusions: The results show that CD1d expression and iNKT cells are dispensable for the development, accumulation, or IL10 competence of CD5+ B cells in mice prone to benign or leukemic CLL-like B cell expansion, but reveal a novel role for iNKT cells in supporting B cell progression through the transitional stage of development in these animals. These results suggest CD1d-directed therapies to target CLL could be evaded by downregulating CD1d expression with little effect on continued leukemic CD5+ B cell survival. The data also imply that iNKT cells help restrain pro-leukemic CD8+ T cell expansion in CLL, potentially explaining a reported correlation in human CLL between disease progression, the loss of NKT cells, and a paradoxical increase in CD8+ T cells.
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U2 - 10.1186/s12865-015-0130-z
DO - 10.1186/s12865-015-0130-z
M3 - Article
C2 - 26537916
AN - SCOPUS:84946206567
VL - 16
JO - BMC Immunology
JF - BMC Immunology
SN - 1471-2172
IS - 1
M1 - 66
ER -