title: Post-chemotherapy and cytokine pretreated marrow stromal cell layers suppress hematopoiesis from normal donor CD34+ cells.
abstract: Marrow stromal layers were used to investigate the potential role of negative regulators produced by the marrow microenvironment as one potential cause of hematopoietic suppression after chemotherapy and cytokines. Stromal layers were established from marrow of normal or prechemotherapy donors and breast cancer patients after hematological recovery from one cycle of 5-fluorouracil, leucovorin, doxorubicin, and cyclophosphamide and GM-CSF or PIXY321 (GM-CSF/IL-3 fusion protein). Normal donor CD34+ cells were placed in contact with stromal layers, and the number of colony-forming units for granulocytes and macrophages (CFU-GM) was determined. There were 25-79% fewer CFU-GM in post-chemotherapy stromal layer cocultures than in no chemotherapy cocultures. With neutralizing antibody to TNF-alpha the number of CFU-GM in no chemotherapy and post-chemotherapy stromal cocultures was, respectively, 96 +/- 7% (n = 5) and 142 +/- 8% (n = 5) of the number with no antibody treatment. PIXY321 and GM-CSF pretreated stromal layers also suppressed production of CFU-GM. Anti-TNF-alpha promoted an increase in CFU-GM numbers from GM-CSF, but not PIXY321, pretreated stromal cocultures. The results demonstrate that post-chemotherapy marrow stromal layers were deficient in supporting in vitro hematopoiesis and suggest that negative regulators induced by chemotherapy and cytokines may be one cause for this defect.
authors.affiliation: Department of Experimental Transplantation and Immunology, National Cancer Institute, Bethesda, MD 20892, USA.
authors.forename: G N
authors.initials: GN
authors.lastname: Schwartz
authors.forename: M K
authors.initials: MK
authors.lastname: Warren
authors.forename: S W
authors.initials: SW
authors.lastname: Rothwell
authors.forename: J
authors.initials: J
authors.lastname: Zujewski
authors.forename: D C
authors.initials: DC
authors.lastname: Halverson
authors.forename: K H
authors.initials: KH
authors.lastname: Cowan
authors.forename: A
authors.initials: A
authors.lastname: Tolcher
authors.forename: J
authors.initials: J
authors.lastname: O'Shaughnessy
authors.forename: R E
authors.initials: RE
authors.lastname: Gress
mesh_terms: D018952:Antigens, CD34; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology* / Q000627:therapeutic use; D001772:Blood Cell Count; D001854:Bone Marrow Cells / Q000187:drug effects / Q000473:pathology*; D001943:Breast Neoplasms / Q000188:drug therapy / Q000473:pathology*; D002450:Cell Communication; D018920:Coculture Techniques; D005260:Female; D006410:Hematopoiesis; D006412:Hematopoietic Stem Cells / Q000166:cytology*; D006801:Humans; D017154:Stromal Cells / Q000187:drug effects / Q000473:pathology*
chemical_list: D018952:Antigens, CD34