Plasmacytoid dendritic cells prime IFN-gamma-secreting melanoma-specific CD8 lymphocytes and are found in primary melanoma lesions.

Journal article

Plasmacytoid dendritic cells (PDC) are a small population of leukocytes specialized in the production of type I IFN. It has been shown that PDC have a potent T cell stimulatory capacity in allogeneic mixed lymphocyte reaction, However, their role in initiating primary immune responses remains elusive. We report that blood PDC efficiently prime naive CD8(+) lymphocytes specific for the melan-A(26-35) epitope to become IFN-gamma producing cells in vitro. In addition, we found that CD40L-stimulated PDC induce expression on primed melan-A-specific T cells of cutaneous lymphocyte antigen and L-selectin (CD62L), homing receptors that allow the migration of effector cells to the inflamed skin. Finally, we show that PDC can be found in the peri-tumoral area of most primary cutaneous melanomas in vivo and that type I IFN-containing supernatants derived from PDC increase melanoma cell surface expression of CD95 and MHC class I and class II molecules in vitro. Our results suggest a new immunomodulatory role for tissue infiltrating PDC, which may prime tumor-specific T cell responses and affect tumor growth via soluble factors.

Authors: Salio, M; Cella, M; Vermi, W; Facchetti, F; Palmowski, M

• Publication status: Published
• Journal: European journal of immunology
• Volume: 33
• Issue: 4
• Pages: 1052-1062
• Publication date: 2003-04-01
• DOI: 10.1002/eji.200323676
• EISSN: 1521-4141
• ISSN: 0014-2980
• Language: English
• Keywords: Interferon-gamma; Tumor Cells, Cultured; Membrane Glycoproteins; Interleukin-12; CD8-Positive T-Lymphocytes; Lymphocyte Activation; Neoplasm Proteins; Lymphocytes, Tumor-Infiltrating; Antigens, Differentiation, T-Lymphocyte; Antigens, Neoplasm; Antigens, CD95; Melanoma; Dendritic Cells; Interferon Type I; Humans; Histocompatibility Antigens; MART-1 Antigen