title: Proliferating cell nuclear antigen (PCNA) expression of megakaryocytopoiesis in normal human bone marrow and reactive lesions with special emphasis on HIV-myelopathy.
abstract: A morphometric analysis was performed on bone marrow trephine biopsies using sequential double-immunostaining, to evaluate endoreduplicative activity of megakaryocytopoiesis. A total of 104 marrow specimens were studied with employment of monoclonal antibodies PC10 (anti-proliferating cell nuclear antigen-PCNA) and Y2/51-CD61 (anti-platelet glycoprotein IIIa). In addition to the control group patients included non-specific inflammatory changes, HIV-myelopathy with normal or decreased platelet counts, idiopathic thrombocytopenic purpura (ITP), and finally reactive thrombocytosis (TH). To exclude an undue overexpression of PCNA, in a comparative pilot study we also applied MIB1 (Ki-67 antigen) on normal bone marrow specimens. In accordance with the various modalities of cell-cycle marker expression, no significantly different findings were disclosed. PCNA-labelling index was relatively low, ranging from 0.8 to 1.7% of the total megakaryocytopoiesis (promegakaryoblasts to mature platelet-shedding megakaryocytes). A significant relationship between megakaryocyte size and PCNA-expression was determinable. This implies that some of the cases with a prevalence of small megakaryocytes, like ITP, have the tendency to show a higher proportion of positively-stained cells. Moreover, this feature confirms a hypothesis postulating a decrease in the time for DNA-synthesis (S-phase) and a relative prolongation of the G1/G2-phases of the cell-cycle at higher ploidy levels (large-sized megakaryocytes). On the other hand, it may be speculated that some of the hyperpolyploid giant megakaryocytes may have reached their endstage of endoreduplication and enter into G0-phase. In comparison with the control group and the other entities under study, a significant reduction of PCNA-reactivity was recognizable in HIV-myelopathy accompanied by thrombocytopenia.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Institute of Pathology, University of Cologne, FRG.
authors.forename: J
authors.initials: J
authors.lastname: Thiele
authors.forename: B R
authors.initials: BR
authors.lastname: Titius
authors.forename: H M
authors.initials: HM
authors.lastname: Kvasnicka
authors.forename: H P
authors.initials: HP
authors.lastname: Bertsch
authors.forename: S
authors.initials: S
authors.lastname: Erdmann
authors.forename: R
authors.initials: R
authors.lastname: Fischer
mesh_terms: D000328:Adult; D001853:Bone Marrow / Q000503:physiopathology*; D001855:Bone Marrow Diseases / Q000503:physiopathology*; D005260:Female; D006410:Hematopoiesis; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D008533:Megakaryocytes; D008875:Middle Aged; D009687:Nuclear Proteins / Q000378:metabolism*; D015493:Paraparesis, Tropical Spastic / Q000503:physiopathology*; D018809:Proliferating Cell Nuclear Antigen; D011696:Purpura, Thrombocytopenic / Q000503:physiopathology; D012016:Reference Values; D013194:Staining and Labeling; D013922:Thrombocytosis / Q000503:physiopathology
chemical_list: D009687:Nuclear Proteins; D018809:Proliferating Cell Nuclear Antigen