Effect of TNF Expression by Stromal Cells on Hemopoietic and Stromal Precursor Cells in Long-Term Bone Marrow Cultures Derived from TNF-Deficient Mice

The effect of TNF expression by wild type stromal sublayer on hemopoiesis was studied in cultures after second inoculation of TNF-deficient bone marrow cells. Long-term maintenance of hemopoiesis was determined solely by the absence of autocrine expression of TNF by hemopoietic cells. The production of hemopoietic precursors of all studied types in TNF-deficient cultures on a wild type sublayer was significantly higher than in cultures without TNF production. Presumably, initial expression of TNF in the sublayer promotes the survival of hemopoietic precursors with high proliferative potential in the culture. It is also obvious that TNF is required for normal functioning of stromal precursor cells. __________ Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 140, No. 11, pp. 561–564, November, 2005