title: Thrombopoietin concentrations in peripheral blood correlated with platelet numbers in two patients with thrombocytopenia by chronic graft-versus-host disease.
abstract: Thrombocytopenia is well known to be one of the clinical manifestations of chronic graft-versus-host disease (cGVHD). However, there exist cases in which the cause of thrombocytopenia has been unexplained. Recently, thrombopoietin (TPO) from bone marrow (BM) stromal cells and transforming growth factor (TGF)-beta from platelets and megakaryocytes have been identified as strong positive and negative regulators of megakaryopoiesis in vivo. We hypothesized that the decreased TPO production from BM could be one of the causes of thrombocytopenia in the patients with cGVHD. In the present study, therefore, TPO and TGF-beta concentrations in peripheral blood (PB) and BM were measured serially in two patients with acute leukemia who had received fully matched stem cell transplantation from relatives and subsequently developed extensive cGVHD with thrombocytopenia. The results showed that platelet numbers correlated well with the TPO concentrations, which were consistently higher in BM than in PB. The difference in TPO concentrations between BM and PB was decreased when the platelet levels were low, indicating that the amount of TPO production from BM decreased throughout the duration of thrombocytopenia. TGF-beta concentrations were normal during all periods in which measurements were carried out. Thus, our results suggest that one mechanism of thrombocytopenia in patients with cGVHD is low TPO production by BM cells.
authors.affiliation: Department of Internal Medicine, Higashi Sapporo Hospital, Sapporo, Japan. yhirayama@hsh.or.jp
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Hirayama
authors.forename: Sumio
authors.initials: S
authors.lastname: Sakamaki
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Tsuji
authors.forename: Tamotsu
authors.initials: T
authors.lastname: Sagawa
authors.forename: Hiroki
authors.initials: H
authors.lastname: Chiba
authors.forename: Takuya
authors.initials: T
authors.lastname: Matsunaga
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kuroda
authors.forename: Toshiro
authors.initials: T
authors.lastname: Kusakabe
authors.forename: Takehide
authors.initials: T
authors.lastname: Akiyama
authors.forename: Junji
authors.initials: J
authors.lastname: Kato
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Niitsu
mesh_terms: D000328:Adult; D001853:Bone Marrow / Q000737:chemistry; D002908:Chronic Disease; D005260:Female; D006086:Graft vs Host Disease / Q000150:complications*; D018380:Hematopoietic Stem Cell Transplantation / Q000009:adverse effects; D006801:Humans; D007938:Leukemia / Q000150:complications / Q000628:therapy; D010976:Platelet Count; D013921:Thrombocytopenia / Q000209:etiology*; D013926:Thrombopoietin / Q000032:analysis* / Q000097:blood; D016212:Transforming Growth Factor beta / Q000032:analysis / Q000097:blood
chemical_list: D016212:Transforming Growth Factor beta; D013926:Thrombopoietin