TY - JOUR
T1 - GRK2 regulates group 2 innate lymphoid cell mobilization in sepsis
AU - Lai, Dengming
AU - Chen, Weiwei
AU - Zhang, Kai
AU - Scott, Melanie J.
AU - Li, Yuehua
AU - Billiar, Timothy R.
AU - Wilson, Mark A.
AU - Fan, Jie
N1 - Publisher Copyright:
© 2022, The Author(s).
PY - 2022/12
Y1 - 2022/12
N2 - Background: Sepsis induces group 2 innate lymphoid cell (ILC2) expansion in the lung. However, the origin of these lung-recruited ILC2 and the mechanism of ILC2 expansion are unclear. This study aims to determine the origin of lung-recruited ILC2 and its underlying mechanism in sepsis. Methods: Sepsis was induced by cecal ligation and puncture (CLP) model in wild-type, IL-33-deficient and ST2-deficient mice. The frequency, cell number and C-X-C chemokine receptor 4 (CXCR4) expression of ILC2 in bone marrow (BM), blood and lung were measured by flow cytometry. In the in vitro studies, purified ILC2 progenitor (ILC2p) were challenged with IL-33 or G protein-coupled receptor kinase 2 (GRK2) inhibitor, the CXCR4 expression and GRK2 activity were detected by confocal microscopy or flow cytometry. Results: We show that IL-33 acts through its receptor, ST2, on BM ILC2p to induce GRK2 expression and subsequent downregulation of cell surface expression of CXCR4, which results in decreasing retention of ILC2p in the BM and promoting expansion of ILC2 in the lung. Importantly, we demonstrate that reduced IL-33 level in aging mice contributes to impaired ILC2 mobilization from BM and accumulation in the lung following sepsis. Conclusion: This study identifies a novel pathway in regulating ILC2p mobilization and expansion during sepsis and indicates BM as the main source of ILC2 in the lung following sepsis.
AB - Background: Sepsis induces group 2 innate lymphoid cell (ILC2) expansion in the lung. However, the origin of these lung-recruited ILC2 and the mechanism of ILC2 expansion are unclear. This study aims to determine the origin of lung-recruited ILC2 and its underlying mechanism in sepsis. Methods: Sepsis was induced by cecal ligation and puncture (CLP) model in wild-type, IL-33-deficient and ST2-deficient mice. The frequency, cell number and C-X-C chemokine receptor 4 (CXCR4) expression of ILC2 in bone marrow (BM), blood and lung were measured by flow cytometry. In the in vitro studies, purified ILC2 progenitor (ILC2p) were challenged with IL-33 or G protein-coupled receptor kinase 2 (GRK2) inhibitor, the CXCR4 expression and GRK2 activity were detected by confocal microscopy or flow cytometry. Results: We show that IL-33 acts through its receptor, ST2, on BM ILC2p to induce GRK2 expression and subsequent downregulation of cell surface expression of CXCR4, which results in decreasing retention of ILC2p in the BM and promoting expansion of ILC2 in the lung. Importantly, we demonstrate that reduced IL-33 level in aging mice contributes to impaired ILC2 mobilization from BM and accumulation in the lung following sepsis. Conclusion: This study identifies a novel pathway in regulating ILC2p mobilization and expansion during sepsis and indicates BM as the main source of ILC2 in the lung following sepsis.
KW - Aging
KW - Bone marrow
KW - Group 2 innate lymphoid cells
KW - Mobilization
KW - Sepsis
UR - http://www.scopus.com/inward/record.url?scp=85126245434&partnerID=8YFLogxK
U2 - 10.1186/s10020-022-00459-8
DO - 10.1186/s10020-022-00459-8
M3 - Article
C2 - 35272622
AN - SCOPUS:85126245434
SN - 1076-1551
VL - 28
JO - Molecular medicine (Cambridge, Mass.)
JF - Molecular medicine (Cambridge, Mass.)
IS - 1
M1 - 32
ER -