Up-regulation of MCP-1 and RANTES by cartilage (149.10)

Abstract

Abstract Immunomodulation refers to changes in an organism’s immune response by factors that either activate or suppress immune function. In previous studies we have shown the presence of immunomodulatory factor(s) in commercial shark cartilage (SC) extracts. Cartilage extracts induce various inflammatory cytokines and a potent chemokine in human peripheral blood leukocytes (HPBL). The cytokine induction profile of SC-stimulated cells includes potent Th1 type cytokines, such as IL-2, TNFα, IFNγ, and IL-1β, two of which are characteristically involved in inflammatory responses and an inflammatory chemokine, IL-8. To further delineate the HPBL response to SC, supernatants from both short-term and long-term primary HPBL cultures were assayed for two potent mediators, macrophage chemoattractant protein 1(MCP-1) and RANTES, by ELISA. Within 4 hours, SC-treated leukocytes produced significantly (p < 0.05) elevated levels of MCP-1 when compared to cultures treated with medium alone and the response was similar to that seen in LPS-treated cultures. After 24 hours, however, the response to LPS was significantly reduced while the response to SC was consistently maintained through 96 hours. In contrast, the production of RANTES by both un-stimulated and stimulated HPBL was relatively consistent through the first 12 hours of culture. RANTES levels in leukocytes treated with medium alone decreased gradually after 24 hours, while those of LPS- and SC-treated cultures remain elevated.