Recruitment of immature plasmacytoid dendritic cells (plasmacytoid monocytes) and myeloid dendritic cells in primary cutaneous melanomas.

摘要: The present study has analysed the distribution and phenotype of dendritic cells (DCs) in primary cutaneous melanomas sentinel lymph nodes by immunohistochemistry. In melanomas, an increase DCs was found epidermis peritumoural area. Intraepidermal were mostly CD1a+/Langerin+ Langerhans cells. Peritumoural included a large population DC-SIGN+/mannose-receptor+/CD1a− DCs, small subset CD1a+ and, remarkably, plasmacytoid monocytes/plasmacytoid (PM/PDCs). PM/PDCs, most likely recruited SDF-1 secreted melanoma cells, produced type I interferon (IFN-I), but expression IFN-α inducible protein MxA extremely variable very limited majority cases. All DC subsets predominantly immature. area also contained minor mature DCs. However, amount local interleukin (IL)-12 p40 mRNA naive 20–50% T-lymphocytes are consistent with poor T-cell stimulation or erroneous recruitment. nodes, notable expansion observed. paucity intratumoural predominant immature dermal indicate defective maturation melanoma-associated resulting lack priming. These results may explain why grow despite presence infiltrating immune Copyright © 2003 John Wiley & Sons, Ltd.