Mouse bone marrow-derived IL-3-dependent mast cells and autonomous sublines produce IL-6

This study deals with the question of whether mouse bone marrow-derived mast cells are able to produce interleukin-6 (IL-6) in vitro. For this purpose, a panel of primary mast cell clones from limiting-dilution microcultures, of permanent IL-3-dependent mast cell lines and autonomous malignant sublines, was screened. All of these lines were found to produce growth factor activity for IL-6-dependent mouse hybridoma cells (7TD1), which could be completely neutralized by the monoclonal anti-IL-6-antibody 6B4. Transcriptional activity of the IL-6 gene was demonstrated in both IL-3-dependent mast cells and autonomous sublines using a mouse IL-6-specific cDNA probe.