NYMC Faculty Publications
Constitutive and LPS-Induced Expression of MCP-1 and IL-8 by Human Uveal Melanocytes in Vitro and Relevant Signal Pathways
Author Type(s)
Faculty
DOI
10.1167/iovs.14-14685
Journal Title
Investigative Ophthalmology & Visual Science
First Page
5760
Last Page
5769
Document Type
Article
Publication Date
8-14-2014
Department
Ophthalmology
Keywords
Cells, Cultured, Chemokine CCL2, Dose-Response Relationship, Drug, Enzyme-Linked Immunosorbent Assay, Humans, Interleukin-8, Lipopolysaccharides, Melanocytes, Mitogen-Activated Protein Kinase Kinases, NF-kappa B, Protein Kinase Inhibitors, RNA, Messenger, Signal Transduction, Uvea
Abstract
PURPOSE: Melanocytes are one of the major cellular components in the uvea. Interleukin-8/CXCL8 and monocyte chemoattractant protein-1 (MCP-1/CCL2) are the two most important proinflammatory chemokines. We studied the constitutive and lipopolysaccharide (LPS)-induced expression of IL-8 and MCP-1 in cultured human uveal melanocytes (UM) and explored the relevant signal pathways.
METHODS: Conditioned media and cells were collected from UM cultured in medium with and without stimulation of LPS. Interleukin-8 and MCP-1 proteins and mRNAs were measured using an ELISA kit and RT-PCR, respectively. Nuclear factor (NF)-κB in nuclear extracts and phosphorylated p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinases1/2 (ERK1/2), and c-Jun N-terminal kinase1/2 (JNK1/2) in cells cultured with and without LPS were measured by ELISA kits. Inhibitors of p38 (SB203580), ERK1/2 (UO1026), JNK1/2 (SP600125), and NF-κB (BAY11-7082) were added to the cultures to evaluate their effects.
RESULTS: Low levels of IL-8 and MCP-1 proteins were detected in the conditioned media in UM cultured without serum. Lipopolysaccharide (0.01-1 μg/mL) increased IL-8 and MCP-1 mRNAs and proteins levels in a dose- and time-dependent manner, accompanied by a significant increase of phosphorylated JNK1/2 in cell lysates and NF-κB in nuclear extracts. Nuclear factor-κB and JNK1/2 inhibitors significantly blocked LPS-induced expression of IL-8 and MCP-1.
CONCLUSIONS: This is the first report on the expression and secretion of chemokines by UM. The data suggest that UM may play a role in the pathogenesis of ocular inflammatory diseases.
Recommended Citation
Hu, D., Bi, M., Zhang, D. Y., Ye, F., McCormick, S. A., & Chan, C. (2014). Constitutive and LPS-Induced Expression of MCP-1 and IL-8 by Human Uveal Melanocytes in Vitro and Relevant Signal Pathways. Investigative Ophthalmology & Visual Science, 55 (9), 5760-5769. https://doi.org/10.1167/iovs.14-14685
