title: An engineered GM-CSF-CCL2 fusokine is a potent inhibitor of CCR2-driven inflammation as demonstrated in a murine model of inflammatory arthritis.
abstract: CCR2 is a chemokine receptor widely expressed by lymphomyeloid cells involved in maladaptive autoimmune ailments. Therefore CCR2 is of great interest as a biological target for immune suppression due to its direct implication in autoimmune diseases such as rheumatoid arthritis. We have generated a novel fusion protein using GM-CSF and an N-terminal truncated version of MCP-1/CCL2 (6-76, GMME1) and investigated its utility as a CCR2-specific immune suppressor. Using BRET studies, we found that distinct to CCL2, GMME1 binding to CCR2 led to altered conformational changes in the CCR2 homodimer and did not induce the recruitment of beta-arrestin 2 to the receptor. However, CCR2-dependent calcium mobilization, BAX induction and caspase-3 activation followed by cell death was observed. Using Th17 cells harvested from DBA/1 mice ill with bovine collagen-induced arthritis, we demonstrate that GMME1 is capable of blocking their production of IL-17 in vitro. Upon its delivery to mice symptomatic with inflammatory arthritis, a robust clinical recovery occurred with decreased paw thickness to normal levels and a significant reduction in anti-collagen Ab titer and rheumatoid factor titer, as well as reduction of proinflammatory cytokines levels both intraarticular and systemic. Our data demonstrate that GMME1 is a powerful synthetic suppressor cytokine that coopts CCR2-dependent cellular signaling and blunts the effects of CCR2-expressing lymphomyeloid cells causative of autoimmune arthritis.
authors: The Montreal Center for Experimental Therapeutics in Cancer, Jewish General Hospital, McGill University, Montreal, Quebéc H3T 1E2, Canada.
authors: Moutih
authors: M
authors: Rafei
authors: Yamina A
authors: YA
authors: Berchiche
authors: Elena
authors: E
authors: Birman
authors: Marie-Noëlle
authors: MN
authors: Boivin
authors: Yoon Kow
authors: YK
authors: Young
authors: Jian Hui
authors: JH
authors: Wu
authors: Nikolaus
authors: N
authors: Heveker
authors: Jacques
authors: J
authors: Galipeau
mesh_terms: D000818:Animals; D001169:Arthritis, Experimental / Q000188:drug therapy* / Q000517:prevention & control; D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000235:genetics*; D004195:Disease Models, Animal; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000235:genetics*; D007249:Inflammation / Q000188:drug therapy / Q000517:prevention & control; D020381:Interleukin-17; D051379:Mice; D011485:Protein Binding; D015202:Protein Engineering / Q000379:methods*; D054390:Receptors, CCR2 / Q000737:chemistry / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000494:pharmacology* / Q000627:therapeutic use; D016176:T-Lymphocyte Subsets
chemical_list: C515334:CCR2 protein, human; D018932:Chemokine CCL2; D020381:Interleukin-17; D054390:Receptors, CCR2; D011993:Recombinant Fusion Proteins; D016178:Granulocyte-Macrophage Colony-Stimulating Factor