MCP-2 and MCP-3 are recently identified members of the Cys-Cys chemokine family with high sequence similarity with MCP-1 (62% and 71%, respectively). The present study was aimed at defining receptor usage and signal transduction pathways of MCP-2 and MCP-3 in human monocytes in comparison with MCP-1. MCP-2 and MCP-3 induced migration of monocytes with a typical bell-shaped curve and maximal response at 10 and 50 ng/ml, respectively. The maximal response elicited by MCP-2 and MCP-3 was lower (approximately 60%) than that of MCP-1. Pertussis toxin (PTox) inhibited the chemotactic activity of MCP-3 and MCP-1 (IC50 = 6.2 and 4.4 ng/ml, respectively), whereas cholera toxin (CTox) had little effect on these two chemokines (IC50 > 1000 ng/ml). In contrast, MCP-2-induced chemotaxis was blocked by CTox (IC50 = 75 ng/ml) and relatively unaffected by PTox. MCP-3 and MCP-1 induced a rapid increase in intracellular Ca2+ concentration, whereas MCP-2, in the range of concentrations active on chemotaxis, did not. MCP-1-, MCP-2-, and MCP-3-induced chemotactic responses were blocked by C-I, a serine/threonine kinase inhibitor, and by genistein, a tyrosine kinase inhibitor, with the MCP-2 response being more sensitive than those induced by MCP-1 and MCP-3. MCP-1 and MCP-3 rapidly induced arachidonic acid release whereas MCP-2 was ineffective. MCP-1 and MCP-3 cross-desensitized with each other in terms of Ca2+ transients and displaced with a comparable efficiency labeled MCP-1 from human monocytes. On the other hand, MCP-2 did not cross-desensitize with MCP-1 and MCP-3 and only partially (20%) displaced labeled MCP-1. Thus, in spite of high sequence similarity, MCP-2 differed considerably from MCP-1 and MCP-3 in terms of sensitivity to CTox and PTox, arachidonate and calcium mobilization, and capacity to compete for labeled MCP-1.
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Graefes Arch Clin Exp Ophthalmol
January 2025
Department of Ophthalmology and Micro-Technology, Yokohama City University, 4-57 Urafunecho, Minami-ku, Yokohama, 232-0024, Kanagawa, Japan.
Purpose: To investigate whether sub-Tenon injection of triamcinolone acetonide (STTA) combined with anti-vascular endothelial growth factor (VEGF) prolongs the recurrence intervals of macular edema (ME) for chronic retinal vein occlusion (RVO) and to investigate the differences in intraocular inflammatory cytokines between good responders (GRs) and non-responders (NRs).
Methods: This retrospective, observational study involved 42 eyes of 42 patients with ME due to chronic RVO who had received only anti-VEGF for ≥ 1 year and were transitioned to combination therapy. GRs were defined as patients whose recurrence intervals were prolonged by ≥ 2 weeks compared with patients receiving anti-VEGF alone.
Exp Biol Med (Maywood)
December 2024
Department of Biological Sciences, Louisiana State University and Pennington Biomedical Research Center, Baton Rouge, LA, United States.
The focus of this study was to identify risk factors for severe and critical COVID-19, evaluate local respiratory immune responses to SARS-CoV-2 infection, and develop a prognostic tool for COVID-19 severity using accessible early indicators. Using nasopharyngeal swab samples from hospitalized patients with COVID-19 of varying severity during the first wave of the pandemic from March to May 2020 in Louisiana, we evaluated the association between COVID-19 severity and viral load, respiratory immune mediators, and demographic/clinical factors. We found that the SpO/FiO ratio at triage, total comorbidity burden (represented by Charlson Comorbidity Index), and gender were significantly associated with COVID-19 severity.
View Article and Find Full Text PDFFront Immunol
November 2024
Faculty of Natural Sciences and Medicine, Ilia State University, Tbilisi, Georgia.
Introduction: The mechanisms of the SARS-CoV-2-triggered complex alterations in immune cell activation and production of cytokines in lung tissue remain poorly understood, in part because of the limited use of adequate tissue models that simulate the structure and cell composition of the lung . We developed a novel model of SARS-CoV-2 infection of lung explants, that maintains the intact tissue composition and the viral load for up to 7-10 days. Using this model, we studied cytokine production during SARS-CoV-2 infection.
View Article and Find Full Text PDFJ Microbiol Immunol Infect
December 2024
Pediatric Infectious Diseases Department, Gregorio Marañón University Hospital, Madrid, Spain; Biomedical Research Centre Network for Infectious Diseases (CIBERINFEC), Carlos III Health Institute, Madrid, Spain; Gregorio Marañón Research Health Institute (IiSGM), Madrid, Spain.
Curr Rheumatol Rev
September 2024
Hospital Pediatry Department, Saint-Petersburg State Pediatric Medical University, Saint-Petersburg, 194100, Russian Federation.
Background: Juvenile idiopathic arthritis pathogenesis involves a large number of different immune system cells, which are both sources and targets of chemokines, that affect not only their migration but also survival, proliferation, differentiation, production of all cytokine types, degranulation, and also directly stimulating or suppressing angiogenesis. Studyingthe contribution of chemokines to this disease pathogenesis will make it possible to identify new sensitive and specific markers for its diagnosis and subsequent dynamic monitoring of treatment effectiveness. The study aimed to identify a list of the most informative diagnostic markers from a wide range of juvenile idiopathic arthritis patients' blood plasma chemokines.
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