Character of interaction between irradiated and non-irradiated cells in culture in diffusion chambers in vivo.

OBJECTIVE

Current investigation is devoted to determination of interaction type between the non-irradiated murine bone-marrow cells and irradiated microenvironment in cell culture in diffusion chambers in vivo.

MATERIALS AND METHODS

To study the characteristics of interaction between the cells we implemented an original cultivation model with bone-marrow cells of intact Balb/c mice inserted in the diffusion chambers in peritoneum of irradiated animals (it provided the access of nutrients and signaling molecules from outside).

RESULTS

As a result of investigations performed, we have determined the direct influence of microenvironment factors of irradiated mice organism on the non-irradiated bone-marrow cells. Thus, cultivation of the cells in the organism of non-irradiated mice revealed a low colony-forming activity due to the absence of additional growth factors release. At the same time an irradiation of the recipient mice and, to a lesser extent, a treatment by cytostatic agent cyclophosphamide increased the proliferative activity of bone-marrow cells in chambers, which indicated the pronounced impact of factors released by the cells as an effect of ionizing radiation. Influence of signaling molecules was realized through the wall of diffusion chamber, causing the stimulation of colony-forming activity. Moreover, we should mention that a direct contact between cells was not necessary for the delivery of a signal.

CONCLUSIONS

Stimulating influence on the colony-forming activity of non-irradiated hematopoietic progenitor cells in diffusion chambers, which is performed by cellular and extra-cellular structures forming external microenvironment, is associated with the action of growth factors produced by irradiated cells and affecting non-irradiated cells through the chamber wall, which is impermeable for the cells but freely transmits diffusible molecules.