Expression of monocyte chemoattractant protein‐1 in primary cultures of rabbit intervertebral disc cells

Publisher Website
Google Scholar
Abstract
Macrophages are considered essential for herniated disc resorption, and chemokines may play a role in their recruitment. Here we demonstrate that intervertebral disc cells are capable of producing monocyte chemoattractant protein‐1 (MCP‐1), a CC chemokine that is chemotactic for macrophages. Nucleus pulposus cells and anulus fibrosus cells were harvested from intervertebral discs of healthy rabbits, and the cells were stimulated with either interleukin (IL)‐1β or tumor necrosis factor (TNF)α. Reverse transcriptase polymerase chain reaction demonstrated that IL‐1β and TNFα induced mRNA expression for MCP‐1 in nucleus pulposus and anulus fibrosus cells. Protein concentrations of MCP‐1 in the culture supernatants were quantitated by fluoroim‐munoassay, which showed that nucleus pulposus and anulus fibrosus cells dose‐ and time‐dependently produced MCP‐1 after IL‐1β‐and TNFα‐stimulation, an event that was completely abrogated by IL‐1 receptor antagonist and anti‐TNFα monoclonal antibody, respectively. Nucleus pulposus cells produced significantly higher levels of MCP‐1 than did anulus fibrosus cells. Immunohisto‐chemically, the intensity of MCP‐1 positive cells in nucleus pulposus cells was stronger than that in anulus fibrosus cells. Altogether, our data clearly demonstrated the production of MCP‐1 in intervertebral disc cells, suggesting the possible involvement of disc cells in an early stage of macrophage infiltration.© 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.