Neutrophil-mediated inflammatory response is a central component of host defense and also plays a major role in tissue damage as observed in many severe pathophysiological conditions. In studies, we found that PMN undergo phenotypic change during active inflammation and such change is associated with SIRP? alteration in PMN. SIRP? is an essential leukocyte signaling receptor that critically regulates PMN function through extracellular binding interactions with CD47 and intracellular signaling via the immunoreceptor tyrosine-based inhibition motifs (ITIMs). Our hypothesis is that critical inflammatory factors produced at post-acute and chronic stages of inflammation induce deletion of SIRP? ITIMs in PMN resulting in enhanced PMN infiltration and intensified inflammation.
Our specific aims are 1) to determine how SIRP? ITIM deletion enhances PMN-mediated inflammatory response, 2) to determine the role of IL-17 in SIRP? ITIM cleavage and identify the responsible protease in PMN, and 3) to determine the therapeutic potential of functional SIRP? ITIM peptides in suppressing PMN infiltration during chronic inflammation. The goal of this project is to discover novel mechanisms underlying dynamic regulation of inflammation and identify new molecular therapeutic targets for drug design in order to alleviate PMN-mediated inflammatory response especially under chronic inflammation.
This project studies mechanisms that control and regulate inflammation and associated leukocyte function. It also aims to discover new diagnostic and therapeutic methods especially targeting chronic inflammatory diseases, including IBD, infection, cardiovascular disease, diabetes, cancer, etc.
|Bian, Zhen; Shi, Lei; Guo, Ya-Lan et al. (2016) Cd47-Sirp? interaction and IL-10 constrain inflammation-induced macrophage phagocytosis of healthy self-cells. Proc Natl Acad Sci U S A 113:E5434-43|
|Niu, Shuo; Bian, Zhen; Tremblay, Alexandra et al. (2016) Broad Infiltration of Macrophages Leads to a Proinflammatory State in Streptozotocin-Induced Hyperglycemic Mice. J Immunol 197:3293-3301|
|Lv, Zhiyuan; Bian, Zhen; Shi, Lei et al. (2015) Loss of Cell Surface CD47 Clustering Formation and Binding Avidity to SIRP? Facilitate Apoptotic Cell Clearance by Macrophages. J Immunol 195:661-71|
|Shi, Lei; Bian, Zhen; Chen, Celia X J et al. (2015) CD47 deficiency ameliorates autoimmune nephritis in Fas(lpr) mice by suppressing IgG autoantibody production. J Pathol 237:285-95|
|Bian, Zhen; Guo, Yalan; Luo, Youqun et al. (2013) CD47 deficiency does not impede polymorphonuclear neutrophil transmigration but attenuates granulopoiesis at the postacute stage of colitis. J Immunol 190:411-7|
|Ha, Binh; Lv, Zhiyuan; Bian, Zhen et al. (2013) 'Clustering' SIRP? into the plasma membrane lipid microdomains is required for activated monocytes and macrophages to mediate effective cell surface interactions with CD47. PLoS One 8:e77615|
|Zhu, Dihan; Pan, Chaoyun; Li, Limin et al. (2013) MicroRNA-17/20a/106a modulate macrophage inflammatory responses through targeting signal-regulatory protein ?. J Allergy Clin Immunol 132:426-36.e8|
|Zen, Ke; Guo, Yalan; Bian, Zhen et al. (2013) Inflammation-induced proteolytic processing of the SIRP? cytoplasmic ITIM in neutrophils propagates a proinflammatory state. Nat Commun 4:2436|
|Bian, Zhen; Guo, YaLan; Ha, Binh et al. (2012) Regulation of the inflammatory response: enhancing neutrophil infiltration under chronic inflammatory conditions. J Immunol 188:844-53|