title: Bone marrow and intrathymic precursors of T-cells produce a factor which enhances colony formation in the spleen.
abstract: Bone marrow Ig-Thy-1-SC-1- stem cells (precursors of T-lymphocytes, PTL, containing the SC-1 antigen) spontaneously secrete a humoral factor. When bone marrow Ig-Thy-1-SC-1- cells were treated with this factor they became able to form haemopoietic colonies in the spleens of lethally irradiated mice. This new colony-stimulating factor (CSF) is thermostable and has a molecular mass of about 25-30 kDa. Production of the CSF by bone marrow SC-1+Thy-1- cells was stimulated by treatment with the thymus preparation Thymoptin. Such treatment of bone marrow SC-1+Thy-1- cells also induced the production of a suppressor factor (thermolabile, molecular mass about 45 kDa), that reversed the effect of the CSF. The CSF and the suppressor factor are both also produced by cortisone-resistant radioresistant L3T4-Lyt-2-SC-1+ thymocytes (i.e. intrathymic PTL). The regulation of haemopoiesis appears to be a normal function of bone marrow PTL.
authors.affiliation: Institute of Immunology, Ministry of Health of the USSR, Moscow.
authors.forename: A A
authors.initials: AA
authors.lastname: Yarilin
authors.forename: I V
authors.initials: IV
authors.lastname: Miroshnichenko
authors.forename: N I
authors.initials: NI
authors.lastname: Sharova
authors.lastname: Talaev VYu
authors.forename: I D
authors.initials: ID
authors.lastname: Ryabinina
authors.forename: V P
authors.initials: VP
authors.lastname: Shichkin
mesh_terms: D000818:Animals; D001853:Bone Marrow / Q000378:metabolism*; D001854:Bone Marrow Cells; D002458:Cell Fractionation; D002460:Cell Line; D003115:Colony-Stimulating Factors / Q000378:metabolism* / Q000502:physiology; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000378:metabolism*; D008297:Male; D051379:Mice; D008808:Mice, Inbred CBA; D010455:Peptides / Q000502:physiology; D013154:Spleen / Q000166:cytology / Q000378:metabolism*; D013601:T-Lymphocytes / Q000166:cytology*; D013947:Thymosin / Q000031:analogs & derivatives*; D013949:Thymus Extracts / Q000502:physiology
chemical_list: D003115:Colony-Stimulating Factors; D010455:Peptides; D013949:Thymus Extracts; C065652:timoptin; D013947:Thymosin