17 research outputs found
Granulocyte-macrophage colony-stimulating factor overrides the immunosuppressive function of corticosteroids on rat pulmonary dendritic cells
Stem Cells143292-299STCE
Failure of periodic ultraviolet radiation treatments to prevent sensitization to nitrogen mustard: a case report
Impaired contact hypersensitivity in untreated psoriasis and the effects of photochemotherapy and dithranol/UV-B
In situ immunological characterization of the infiltrating cells in positive patch tests
Immunoregulatory properties of pulmonary surfactant: effect of lung lining fluid on proliferation of human blood lymphocytes.
Progressor but not regressor skin tumours inhibit Langerhans' cell migration from epidermis to local lymph nodes
Langerhans' cells (LC) are found in high numbers infiltrating skin tumours, the functional significance of which remains unknown. To study the mechanism by which tumours increase the number of LC we developed a procedure whereby supernatant from cultured T7 tumour cells applied topically increases the number of LC. Tumour factors increased the number of resident epidermal LC and did not attract LC precursors into parental murine skin grafted onto F1 hybrids. There was no evidence for increased LC division in response to the tumour-derived factors. LC migration from the epidermis to local lymph nodes, induced by topical fluorescein isothiocyanate (FITC), was inhibited by the tumour supernatant. To examine the functional significance of this, FITC-induced migration of LC from the epidermis overlying progressor tumours, which evade immunological destruction, and regressor tumours, which are immunologically destroyed, was examined. The progressor tumour T7 growing subcutaneously in syngeneic mice inhibited FITC-induced migration of LC from overlying epidermis. Furthermore, two progressor, but not two regressor murine skin tumour lines growing in BALB/c nu/nu mice inhibited LC migration from the epidermis. Our results demonstrate that progressor skin tumours produce factor(s) which inhibit LC migration from the epidermis to lymph nodes, leading to LC accumulation. Inhibition of LC migration by tumour-derived factors may enable tumours to evade the activation of protective immunity as regressor tumours do not interfere with the normal trafficking of LC