Flow cytometric analysis of intracellular chemokines in chondrocytes in vivo: constitutive expression and enhancement in osteoarthritis and rheumatoid arthritis

Chemokines play a key role in modulating leukocyte functions at sites of in flammation. To assess chondrocyte contribution to the chemotactic environme nt of inflamed joints the intracellular content of CC and CXC chemokines ma s investigated, IL-8, GRO alpha MCP-1, RANTES, MIP-1 alpha and MIP-1 beta e xpression was evaluated by flow cytometric analysis and RT-PCR in chondrocy tes isolated from cartilage specimens obtained from patients with osteoarth ritis and rheumatoid arthritis and multiorgan donors as normal controls. Al l the chemokines except RANTES were found in normal chondrocytes, with diff erent degrees of staining intensity, In osteoarthritis and rheumatoid arthr itis patients, an enhancement of IL-8, GRO alpha, MIP-1 alpha and MIP-1 bet a was observed. (C) 1999 Federation of European Biochemical Societies.