Alessi M C, Chomiki N, Berthier R, Schweitzer A, Fossat C, Juhan-Vague I
Laboratory of Hematology, CHU Timone, Marseille, France.
Thromb Haemost. 1994 Dec;72(6):931-6.
Platelets have been described to contain a large proportion of the circulating plasminogen activator inhibitor type 1 (PAI-1) which is released on platelet activation. This protein could be taken up by platelets from the plasma or synthesized by megakaryocytes (MKs). Recently, PAI-1 mRNA has been detected in a human megakaryoblastic leukemia cell line (MEG-01) by the polymerase chain reaction (PCR). However, a direct-demonstration of its presence in normal human MKs is lacking. In order to prove directly the megakaryocytic origin of platelet PAI-1, the MEG-01 cell line, human bone marrow enriched in MKs, and bone marrow smears from allogeneic bone marrow transplantation donors were investigated for the presence of PAI-1 mRNA using in situ hybridization (ISH). Specimens of bone marrow were first stained with May-Grünwald Giemsa (MGG) for cell identification according to their morphology. Subsequently, the same slides were used for ISH. PAI-1 mRNA was clearly demonstrated in the MEG-01 cell line and in MKs, and its presence correlated with the detection of PAI-1 antigen by immunocytochemistry. PAI-1 mRNA was also detected in morphologically characterized mature granulocytes of marrow samples.
血小板被认为含有大量循环中的纤溶酶原激活物抑制剂1型（PAI-1），其在血小板激活时释放。这种蛋白质可以从血浆中被血小板摄取，或者由巨核细胞（MKs）合成。最近，通过聚合酶链反应（PCR）在人巨核母细胞白血病细胞系（MEG-01）中检测到了PAI-1 mRNA。然而，缺乏其在正常人类MKs中存在的直接证据。为了直接证明血小板PAI-1的巨核细胞起源，使用原位杂交（ISH）研究了MEG-01细胞系、富含MKs的人骨髓以及同种异体骨髓移植供体的骨髓涂片，以检测PAI-1 mRNA的存在。首先用May-Grünwald Giemsa（MGG）对骨髓标本进行染色，以便根据其形态识别细胞。随后，将同一张玻片用于ISH。在MEG-01细胞系和MKs中清楚地证明了PAI-1 mRNA的存在，并且其存在与通过免疫细胞化学检测到的PAI-1抗原相关。在骨髓样本中形态学特征明确的成熟粒细胞中也检测到了PAI-1 mRNA。
