Upon dendritic cell (DC) activation chemokines and chemokine receptor expression are rapidly regulated for recruitment and maintenance of DC at the inflammatory site

Dendritic cells (DC) are highly motile antigen-presenting cells that are re cruited to sites of infection and inflammation to antigen uptake and proces sing. Then, to initiate T cell-dependent immune responses, they migrate fro m non-lymphoid organs to lymph nodes and the spleen. Since chemokines have been involved in human DC recruitment, we investigated the role of chemokin es on mouse DC migration using the mouse growth factor-dependent immature D C line (D1), In this study, we characterized receptor expression, responsiv eness to chemoattractants and chemokine expression of D1 cells during the m aturation process induced by lipopolysaccharide (LPS), MIP-la and MIP-5 wer e found to be the most effective chemoattractants, CCR1 was the main recept or expressed and modulated during LPS treatment, and MIP-2, RANTES, IP-10 a nd MCP-1 were the chemokines modulated during DC maturation. Thus, murine D C respond to a unique set of CC and CXC chemokines, and the maturational st age determines the program of chemokine receptors and chemokines that are e xpressed. Since CCR1 is modulated during the early phases of DC maturation, our results indicate that the CCR1 receptor may participate in the recruit ment and maintenance of DC at the inflammatory site.