Abstract
MD90, a factor-dependent clone derived from an in vitro-adapted murine plasmacytoma parent cell line, proliferated in respose to murine and human interleukin (IL) -6, but not murine IL-1β, IL-2, IL-3, IL-4, IL-7, interferon (IFN) -γ, tumor necrosis factor (TNF) -α, granulocyte/macrophage-colony stimulating factor (GM-CSF), or lipopolysaccharide (LPS). IL-5 also promoted the proliferation of MD90 cells but to a much lesser extent. Anti-IL-5 monoclonal antibodies inhibited the proliferation of MD90 cells in response to IL-5 but not to IL-6. Anti-IL-6 monoclonal antibodies inhibited the proliferation of MD90 cells in response to IL-6 but not to IL-5. These results confirm the novel specificity of MD90 and demonstrate that MD 90 cells are directly responsive to IL-5 and IL-6. These data indicate that MD90 cells can serve as a simple bioassay for IL-5 /IL-6 and can be made monospecific for IL-5 or IL-6 using anti-IL-5 or anti-IL-6.
