TY - JOUR
T1 - Role for microglia in sex differences after ischemic stroke
T2 - importance of M2
AU - Bodhankar, Sheetal
AU - Lapato, Andrew
AU - Chen, Yingxin
AU - Vandenbark, Arthur A.
AU - Saugstad, Julie A.
AU - Offner, Halina
N1 - Publisher Copyright:
© 2015, Springer Science+Business Media New York.
PY - 2015/12/1
Y1 - 2015/12/1
N2 - Inflammation plays a critical role in the pathogenesis of ischemic stroke. This process depends, in part, upon proinflammatory factors released by activated resident central nervous system (CNS) microglia (MG). Previous studies demonstrated that transfer of IL-10+ B-cells reduced infarct volumes in male C57BL/6 J recipient mice when given 24 h prior to or therapeutically at 4 or 24 h after experimental stroke induced by 60 min middle cerebral artery occlusion (MCAO). The present study assesses possible sex differences in immunoregulation by IL-10+ B-cells on primary male vs. female MG cultured from naïve and ischemic stroke-induced mice. Thus, MG cultures were treated with recombinant (r)IL-10, rIL-4 or IL-10+ B-cells after lipopolysaccharide (LPS) activation and evaluated by flow cytometry for production of proinflammatory and anti-inflammatory factors. We found that IL-10+ B-cells significantly reduced MG production of TNF-α, IL-1β and CCL3 post-MCAO and increased their expression of the anti-inflammatory M2 marker, CD206, by cell-cell interactions. Moreover, MG from female vs. male mice had higher expression of IL-4 and IL-10 receptors and increased production of IL-4, especially after treatment with IL-10+ B-cells. These findings indicate that IL-10-producing B-cells play a crucial role in regulating MG activation, proinflammatory cytokine release and M2 phenotype induction, post-MCAO, with heightened sensitivity of female MG to IL-4 and IL-10. This study, coupled with our previous demonstration of increased numbers of transferred IL-10+ B-cells in the ischemic hemisphere, provide a mechanistic basis for local regulation by secreted IL-10 and IL-4 as well as direct B-cell/MG interactions that promote M2-MG.
AB - Inflammation plays a critical role in the pathogenesis of ischemic stroke. This process depends, in part, upon proinflammatory factors released by activated resident central nervous system (CNS) microglia (MG). Previous studies demonstrated that transfer of IL-10+ B-cells reduced infarct volumes in male C57BL/6 J recipient mice when given 24 h prior to or therapeutically at 4 or 24 h after experimental stroke induced by 60 min middle cerebral artery occlusion (MCAO). The present study assesses possible sex differences in immunoregulation by IL-10+ B-cells on primary male vs. female MG cultured from naïve and ischemic stroke-induced mice. Thus, MG cultures were treated with recombinant (r)IL-10, rIL-4 or IL-10+ B-cells after lipopolysaccharide (LPS) activation and evaluated by flow cytometry for production of proinflammatory and anti-inflammatory factors. We found that IL-10+ B-cells significantly reduced MG production of TNF-α, IL-1β and CCL3 post-MCAO and increased their expression of the anti-inflammatory M2 marker, CD206, by cell-cell interactions. Moreover, MG from female vs. male mice had higher expression of IL-4 and IL-10 receptors and increased production of IL-4, especially after treatment with IL-10+ B-cells. These findings indicate that IL-10-producing B-cells play a crucial role in regulating MG activation, proinflammatory cytokine release and M2 phenotype induction, post-MCAO, with heightened sensitivity of female MG to IL-4 and IL-10. This study, coupled with our previous demonstration of increased numbers of transferred IL-10+ B-cells in the ischemic hemisphere, provide a mechanistic basis for local regulation by secreted IL-10 and IL-4 as well as direct B-cell/MG interactions that promote M2-MG.
KW - IL-10-secreting B-cells
KW - M1 and M2 MG states
KW - MCAO
KW - Microglia
UR - http://www.scopus.com/inward/record.url?scp=84947031340&partnerID=8YFLogxK
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U2 - 10.1007/s11011-015-9714-9
DO - 10.1007/s11011-015-9714-9
M3 - Article
C2 - 26246072
AN - SCOPUS:84947031340
SN - 0885-7490
VL - 30
SP - 1515
EP - 1529
JO - Metabolic brain disease
JF - Metabolic brain disease
IS - 6
ER -