title: Exposure to myeloma cell lysates affects the immune competence of dendritic cells and favors the induction of Tr1-like regulatory T cells.
abstract: The aim of this work was to investigate the interactions of tumor cells with dendritic cells (DC) in normal donors and patients with multiple myeloma (MM). Normal and MM DC internalized necrotic lysates derived from myeloma cell lines (MCL) with high efficiency, whereas necrotic lysates from primary myeloma cells (PMC) were internalized with significantly lower efficiency. A positive correlation was found between susceptibility to internalization and the ability to induce DC maturation. After PMC exposure, DC produced large amounts of IL-10 and measurable amounts of IL-4 but no detectable IL-12. Two rounds of exposure to PMC-treated DC generated autologous T cells with low proliferative capacity, decreased IFN-gamma production and increased IL-10 production in the absence of IL-4 production. These data indicate that myeloma cells can affect host immunity by priming DC towards a maturation state favoring the generation of T cells with a regulatory rather than an effector phenotype.
authors.affiliation: Divisione di Ematologia dell'Università di Torino, Torino, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Fiore
authors.forename: Barbara
authors.initials: B
authors.lastname: Nuschak
authors.forename: Silvia
authors.initials: S
authors.lastname: Peola
authors.forename: Sara
authors.initials: S
authors.lastname: Mariani
authors.forename: Michela
authors.initials: M
authors.lastname: Muraro
authors.forename: Myriam
authors.initials: M
authors.lastname: Foglietta
authors.forename: Marta
authors.initials: M
authors.lastname: Coscia
authors.forename: Benedetto
authors.initials: B
authors.lastname: Bruno
authors.forename: Mario
authors.initials: M
authors.lastname: Boccadoro
authors.forename: Massimo
authors.initials: M
authors.lastname: Massaia
mesh_terms: D002454:Cell Differentiation / Q000276:immunology; D002457:Cell Extracts / Q000276:immunology*; D003713:Dendritic Cells / Q000276:immunology*; D006801:Humans; D009101:Multiple Myeloma / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D002457:Cell Extracts