title: Circulating thrombopoietin concentrations in thrombocytopenic patients, including cancer patients following chemotherapy, with or without peripheral blood progenitor cell transplantation.
abstract: Thrombopoietin, the ligand for the c-mpl receptor, promotes proliferation and maturation of megakaryocytes. An ELISA using a chimaeric receptor, mpl-IgG, for capture, and rabbit antibody to thrombopoietin for detection was developed for the quantitation of thrombopoietin in human serum or plasma. This ELISA preferentially detects full-length thrombopoietin compared to the bioactive N-terminal half of the molecule which has homology to erythropoietin. Thrombopoietin was not detected (< 0.16 ng/ml) in 88/89 healthy individuals. However, elevated thrombopoietin concentrations of up to 3 ng/ml were detected in 59/63 thrombocytopenic patients, including cancer patients following chemotherapy. In cancer patients receiving chemotherapy with (n = 12) or without (n = 6) peripheral blood progenitor cell transplantation, thrombopoietin concentrations varied inversely with platelet counts throughout the treatment period. In general, patients who received myeloablative chemotherapy on days -7 to -2 and peripheral blood progenitor cell transplantation on day 0 had high thrombopoietin levels (0.6-2.9 ng/ml) around day 5. Low platelet counts (< 20 x 10(9)/l) occurred between days 4 and 9. Patients who received high-dose chemotherapy on day 1 (equivalent to day -7 for transplantation patients) to day 6 without transplantation had high thrombopoietin concentrations (1.4-2.3 ng/ml) around day 13 and low platelet counts occurred between days 7 and 17.
authors.affiliation: BioAnalytical Technology and Molecular Oncology Department, Genentech Inc., South San Francisco, California, USA.
authors.forename: Y G
authors.initials: YG
authors.lastname: Meng
authors.forename: T G
authors.initials: TG
authors.lastname: Martin
authors.forename: M L
authors.initials: ML
authors.lastname: Peterson
authors.forename: M A
authors.initials: MA
authors.lastname: Shuman
authors.forename: R L
authors.initials: RL
authors.lastname: Cohen
authors.forename: W L
authors.initials: WL
authors.lastname: Wong
mesh_terms: D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D004797:Enzyme-Linked Immunosorbent Assay; D004921:Erythropoietin / Q000378:metabolism; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000097:blood / Q000188:drug therapy / Q000628:therapy*; D010976:Platelet Count; D013921:Thrombocytopenia / Q000097:blood*; D013926:Thrombopoietin / Q000737:chemistry / Q000378:metabolism*
chemical_list: D000970:Antineoplastic Agents; D004921:Erythropoietin; D013926:Thrombopoietin