Establishment and characterization of nurse cell-like clones from human skin: Nurse cell-like clones can stimulate autologous mixed lymphocyte reaction

We have established nurse cell-like clones from long-term cultures of the human skin. These human skin nurse cell (HSNC)-like clones were type I collagen⁺, type IV collagen^-, vimentin⁺, cytokeratin^-, CD44⁺, CD54⁺, and weakly positive for VCAM-1, and easily identified by the pseudoemperipolesis that allowed T lymphocytes to migrate beneath the HSNCs. HSNCs and various T cell lines formed a typical complex in the hanging drop culture system. The majority of human and murine T cells, and some of the tumor cell lines other than T cells, including B lymphoma and myeloblastoma cells, migrated beneath the HSNC clones. HSNC clones produced various cytokines, including IL-6, IL-7, IL-8, IL-9, granulocyte CSF (G-CSF), granulocyte-macrophage CSF (GM-CSF), macrophage CSF (CSF-1), TGF-β1, and c- kit ligand, but could not produce IL-1α, IL-1β, IL-2, IL-3, IL-4, TNF-α, or TNF-β. These characteristics were similar to those of nurse cells established from the murine thymus. Furthermore, IFN-γ-pretreated HSNC clones that expressed MHC class II Ags induced autologous mixed lymphocyte reaction (AMLR) in autologous PBMCs to proliferate and exhibit the cytotoxicity against altered autologous cells and various tumor cells. These results suggest that HSNCs play an important role in the immunoregulation at skin tissues.