Effects of calcitriol and its analogues on interaction of MCP-1 and monocyte derived dendritic cells in vitro.
AIM
To study the effect of calcitriol [1,25(OH)2D3] and its analogues on the interaction of monocyte chemoattractant protein-1 (MCP-1) and in vitro generated monocyte-derived dendritic cells (MoDC).


METHODS
MoDC were obtained by differentiating monocytes in exposure to GM-CSF and IL-4 for 5 d. mRNA expression of MCP-1 and its receptors were analyzed by RT-PCR, and protein production of MCP-1 by ELISA and migratory ability of MoDC in response to MCP-1 by a micromultiwell chemotaxis chamber assay.


RESULTS
MoDC can express MCP-1 mRNA, and secret a low level of MCP-1 protein and has the ability to migrate to MCP-1 in corresponding to its expression of MCP-1 receptors. Calcitriol and its analogues with the same affinity to vitamin D receptor up-regulated the gene expression of both MCP-1 and its receptors, enhanced MCP-1 protein production and promoted the migratory ability of MoDC to MCP-1.


CONCLUSION
The interaction of DC and MCP-1 found in this study may suggest a possible auto-regulatory role between DC and MCP-1 and the modulatory effect of calcitriol and its analogues on DC and MCP-1 might provide an understanding of their positive role in tumors.