title: Thymosin alpha 1 enhances haemopoietic colony formation by stimulating the production of interleukin 3 in nu/nu mice.
abstract: We have studied the action mechanism of thymosin alpha 1 in modulation of haemopoietic system. The present study demonstrated that thymosin alpha 1 enhanced the colony formation as determined by CFU-s, GM-CFU and T-CFU, as well as the production of IL-3, when administered twice a week for a total of six or twelve times into nu/nu mice. The incubation of bone marrow cells with thymosin alpha 1 in vitro did not cause an increase of CFU-s, in contrast to IL-3 which caused a marked increase of CFU-s during the incubation of 72 h. These experiments indicate that thymosin alpha 1 exerts its effect on colony formation of haemopoietic stem cells (CFU-s) indirectly through the enhancement of the IL-3 production. The present finding may support clinical applications of thymosin alpha 1 in a wide range, since IL-3 is known to be the growth factor for many kinds of haemopoietic precursor cells including not only CFU-s but also GM-CFU, BFU-E, Eos-CFU, Meg-CFU, Mast cells, Pre B-cells and Pre T-cells.
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells; D002478:Cells, Cultured; D003114:Colony-Forming Units Assay; D005260:Female; D006410:Hematopoiesis / Q000187:drug effects*; D007377:Interleukin-3 / Q000096:biosynthesis*; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D013154:Spleen / Q000166:cytology; D013601:T-Lymphocytes / Q000187:drug effects; D000077596:Thymalfasin; D013947:Thymosin / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: D007377:Interleukin-3; D013947:Thymosin; D000077596:Thymalfasin