A novel role for myeloid cell-specific neuropilin 1 in mitigating sepsis.
Sepsis-typically caused by an uncontrolled and amplified host systemic inflammatory response to microbial infection-is a life-threatening complex clinical disorder and remains a major cause of infection-related deaths in the intensive care unit. Emerging evidence suggests that neuropilin 1 (Nrp1), an originally defined coreceptor for class 3 semaphorins and VEGF, plays important roles in the immune system; however, the function and regulation of macrophage Nrp1 in host immune defense against bacterial infection remain unknown. To address this problem, we generated myeloid cell-specific Nrp1-knockout (Nrp1myel-KO) mice and applied 2 stringent animal models of sepsis: cecal ligation and puncture as well as intraperitoneal injection of LPS. Here, we reported that myeloid cell-specific Nrp1-deficient mice exhibited enhanced susceptibility to cecal ligation and puncture- and LPS-induced sepsis, which correlated with significantly decreased survival rates and heightened levels of proinflammatory cytokines in both peritoneal lavage and serum. Mechanistically, LPS specifically attenuated the expression of Nrp1 in macrophages, which was mediated by TLR4-NF-κB p50 and -65 pathways. By using isolated primary macrophages, loss of Nrp1 consistently resulted in increased production of proinflammatory cytokines, including iNOS, TNF-α, and IL-6. Together, these findings demonstrate a novel role of macrophage Nrp1 in sepsis.-Dai, X. Okon, I., Liu, Z., Wu, Y., Zhu, H., Song, P., Zou, M.-H. A novel role for myeloid cell-specific neuropilin 1 in mitigating sepsis.
Center for Molecular and Translational Medicine, Georgia State University, Atlanta, Georgia, USA.
Xiaoyan
X
Dai
Center for Molecular and Translational Medicine, Georgia State University, Atlanta, Georgia, USA.
Imoh
I
Okon
Center for Molecular and Translational Medicine, Georgia State University, Atlanta, Georgia, USA.
Zhaoyu
Z
Liu
Department of Cardiology, Cardiovascular Research Center, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
Yue
Y
Wu
Center for Molecular and Translational Medicine, Georgia State University, Atlanta, Georgia, USA.
Huaiping
H
Zhu
Center for Molecular and Translational Medicine, Georgia State University, Atlanta, Georgia, USA.
Ping
P
Song
Center for Molecular and Translational Medicine, Georgia State University, Atlanta, Georgia, USA; mzou@gsu.edu.
Ming-Hui
MH
Zou
D000818:Animals; D005786:Gene Expression Regulation / Q000502:physiology*; D008070:Lipopolysaccharides; D017737:Macrophages, Peritoneal / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D022423:Myeloid Cells / Q000378:metabolism*; D052002:NF-kappa B p50 Subunit / Q000235:genetics / Q000378:metabolism; D039942:Neuropilin-1 / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018805:Sepsis / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology; D051197:Toll-Like Receptor 4 / Q000235:genetics / Q000378:metabolism; D051996:Transcription Factor RelA / Q000235:genetics / Q000378:metabolism
D008070:Lipopolysaccharides; D052002:NF-kappa B p50 Subunit; D012333:RNA, Messenger; C493487:Tlr4 protein, mouse; D051197:Toll-Like Receptor 4; D051996:Transcription Factor RelA; D039942:Neuropilin-1
LPS; inflammation; macrophage