title: Restoring capacity of immunomodifiers for radiation-induced inhibition of colony-forming T cells.
abstract: Six immunomodifier drugs have been studied with regard to their capacity for decreasing radiation-induced effects on lymphocytes. The T cell colony method was selected for this evaluation because this technique takes into account reproductive integrity of the lymphocyte. Irradiation was delivered either in vitro to murine splenocytes or in vivo (total body) at 0.75 Gy, a dose close to the D37 calculated for lymphocyte survival, using the same technique. Among immunomodifiers, only the drugs known for their specific action on ionizing radiation effects (quenching of free radicals) were shown capable of radiorestoration: this is essentially true for retinoic acid--even more than for its derivative--which restored the T cell colony formation up to 80% of the control at 10(-6) M final concentration in vitro. However, when given in vivo to irradiated mice, retinoic acid is active only at high doses.
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000818:Animals; D002945:Cisplatin / Q000494:pharmacology; D002999:Clone Cells / Q000528:radiation effects; D003114:Colony-Forming Units Assay; D005260:Female; D007376:Interleukin-2 / Q000096:biosynthesis; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D011837:Radiation-Protective Agents; D013601:T-Lymphocytes / Q000187:drug effects / Q000528:radiation effects*; D014212:Tretinoin / Q000494:pharmacology
chemical_list: D000276:Adjuvants, Immunologic; D007376:Interleukin-2; D011837:Radiation-Protective Agents; D014212:Tretinoin; D002945:Cisplatin