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A 25-year-old male physician with acute hepatitis C after needle-stick injury was treated with combination therapy including twice-a-day interferon-beta (IFN-beta) and standard interferon-alpha (IFN-alpha). The infecting strain was of genotype 1b. Pretreatment hepatitis C virus (HCV) RNA levels were high. Because severe paresthesias occurred with initial daily administration of 5 million units (MU) of lymphoblastoid IFN-alpha, the dose was reduced to 3 to 6 MU of IFN-alpha2b three times a week. However, HCV RNA was not cleared from serum after 20 weeks of standard IFN-alpha2b treatment. A 4-week course with IFN-beta, at the dosage of 3 MU twice daily i.v. drip, was then started and followed by an 18-week course with IFN-alpha2b, 6 MU thrice weekly. After IFN-beta treatment, HCV RNA was cleared from serum without severe adverse effects, including paresthesias. Total amounts of IFN administered were 20 MU of lymphoblastoid IFN-alpha, 648 MU of IFN-alpha2b, and 252 MU of IFN-beta. Complete response and avoidance of chronic HCV infection were achieved. Thus, combination therapy with twice-a-day IFN-beta and standard IFN-alpha was effective in treating an acute hepatitis C patient with a high viral load and sensitivity to adverse effects of high-dose IFN-alpha.

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To determine the optimal time of peripheral blood stem cell harvest (PBSCH), we evaluated the usefulness of the detection of immature hematopoietic cells (immature leukocytes and reticulocytes) using newly developed automatic cell analyzers, and compared the results with those of conventional CD34 measurement by flow cytometry (FCM). The presence of immature leukocytes and reticulocytes was calculated as immature leukocyte information (IMI)-positive rate and high fluorescence reticulocyte (HFR)-positive rate by multi-item autoanalyzers. Both the IMI-positive rate and HFR-positive rate positively correlated with the CD34-positive rate and was more highly correlated with the colony forming units-mixed (CFU-Mix) count in peripheral blood. In addition, they positively correlated not only with the CD34-positive rate, but also with the colony forming units-granulocyte/macrophage (CFU-GM) count and CFU-Mix count in harvested stem cell juice. These findings imply that the parameters of IMI and HFR could be used for determining the optimal time of PBSCH, and could also be useful for quantifying stem cells.

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Platelet adhesion to the exposed surface of the extracellular matrix in flowing blood is the first and critical reaction for in vivo thrombus formation. However, the mechanism of this in vivo platelet adhesion has yet to be studied extensively. One of the reasons for this is the lack of a practical assay method for assessing platelet adhesion under flow conditions. We have devised an assay method (the fluorescent adhesion assay) that is based on the technique originally reported by Hubbell and McIntire (Biomaterials 7:354, 1986) with some modifications to make it more amenable for assaying small samples and have developed an analysis method to quantify the extent of platelet adhesion and aggregation from fluorescence images by using a computer-assisted image analysis system. In our assay, platelet adhesion, expressed as the percentage of the area covered by adhered platelets, was found to increase biphasically as a function of time. In the first phase, platelets interacted with the coated collagen, transiently stopping on the surface; we called this reaction the temporary arrest. In the second phase, platelets adhered much more rapidly and permanently on the surface, and this adhesion was dependent on the shear rate; platelets formed aggregates in this phase. We used our assay to analyze the effects of platelet aggregation inhibitors on platelet adhesion. All three examined inhibitors, EDTA (10 mmol/L), antiglycoprotein (GP) IIb/IIIa, and GRGDS peptide (1 mmol/L), inhibited the second phase adhesion in flowing blood. Furthermore, GPVI-deficient platelets also showed defective second-phase adhesion under the same conditions. These results suggested that GPIIb/IIIa activation and GPVI contribute to the reaction inducing the second phase. The second-phase adhesion has been extensively investigated, and the consensus is that this reaction is mainly attributable to the platelet-platelet interaction. In this report, we were able to detect an earlier reaction, the temporary arrest. This temporary arrest would reflect the fast and weak interaction between platelet GPIb/IX and collagen-von Willebrand factor complexes on the collagen-coated surface.

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In contrast to therapeutic benefits of interferon-alpha (IFN-alpha) in patients with human T lymphotropic virus type I (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP), little is known about the mechanisms underlying its clinical efficacy. To investigate the anti-viral and/or immunomodulatory properties of IFN-alpha in HTLV-I infection, the effects of IFN-alpha on HTLV-I-induced in vitro phenomena were evaluated. In vitro activation of HTLV-I in fractionated CD4+ T lymphocyte-rich cells (CD4+ cells) could be demonstrated by increased thymidine incorporation into the cells, detection of proviral HTLV-I and viral RNA, and by assays of reverse transcriptase activities in culture supernatants. T cell immune responses were evaluated by thymidine incorporation into CD8+ T lymphocyte-rich cells (CD8+ cells) responding to cultured and irradiated autologous CD4+ cells possessing HTLV-I antigens. It could be shown that IFN-alpha suppressed both the in vitro activation of HTLV-I and the CD8+ cell response. Moreover, 1 day supplementation of IFN-alpha as a pretreatment was sufficient for the induction of these properties. These findings, together with the clinical efficacy of IFN-alpha administration in patients with HAM/TSP, support the view that viral activation and T cell responses are critical components in the pathogenic processes involved in HAM/TSP.

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Homologous transfusion has been known to cause viral infections and other complications. Recently, autologous transfusion has been adopted widely as a safer and more effective procedure to prevent these complications. The authors report the experiences of 29 patients who had been operated on after preparation of autologous blood. Furthermore, the authors report a study concerning maximum surgical blood order schedule (MSBOS) of these operations. 212 patients operated on between January, 1991 and June, 1993 were used for this study of MSBOS. Although intraoperative transfusion was performed on 14 of 29 patients, the need for homologous transfusion was avoided in 12 of these 14 patients by the use of autologous blood. The frequency of homologous transfusion was reduced significantly after the introduction of pre-operative autologous blood collection in our clinic. The patients' value of hemoglobin fell after the collection of blood but these levels were not so seriously low as to impede the performance of operations. 212 cases of operated patients were divided according to the operative methods and diagnosis for calculation of MSBOS. The results were as follows; Craniotomy and removal of glioma 5u, meningioma 11u, neurinoma 7u, AVM 5u, transsphenoidal surgery 3u, Moyamoya disease 2u and V-P or S-P shunt 0u. Pre-operative autologous blood collection is easy to achieve for scheduled neurosurgical operations, and autologous transfusion is a beneficial procedure which should be used more widely.

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Thrombomodulin is an endothelial cell surface glycoprotein that forms a 1:1 complex with thrombin. In this form, thrombin can activate approximately 1,000-fold more protein C than thrombin alone and does not activate coagulation factors, V and VIII, and platelets. Activated protein C inactivates factors Va and VIIIa. Thus thrombomodulin converts thrombin from a procoagulant protease to an anticoagulant. The soluble thrombomodulin present in human urine and plasma appears to represent a truncated form that lacks the transmembrane and cytoplasmic domains of tissue thrombomodulin. The plasma level of thrombomodulin has been used as a marker for endothelial injury in vivo. Elevated levels of soluble thrombomodulin were reported in the plasma from the patients with disseminated intravascular coagulation, adult respiratory distress syndrome (ARDS), and diabetes mellitus retinopathy.

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One of the major regulatory mechanisms operating in the blood coagulation cascade is the thrombomodulin-protein C anticoagulant pathway. It consists of thrombin, thrombomodulin, protein C (PC) and protein S (PS), and is initiated when the circulating zymogen PC is converted to activated PC (APC) by a thrombin-thrombomodulin complex on the surface of endothelial cells. The formed APC in the presence of its co-factor PS, downregulates the coagulation cascade by proteolytic inactivation of the procoagulant cofactors Va and VIIIa, and also enhances the fibrinolysis system by inhibition of plasminogen activator inhibitor 1. PS circulates in plasma in two forms in dynamic equilibrium. One is the free protein (approximately 40% of total PS in normal plasma) which has the APC cofactor activity; the other is the protein reversibly complexed to C4b-binding protein (C4bp), a regulatory component of the complement system. When bound to C4bp, PS can no longer function as a cofactor of APC. As complexing of PS with C4bp is regulated by the law of mass action, elevation of C4bp leads to reduced levels of free (active) PS. In comparison with antithrombin III, heparin cofactor II contributes less in neutralizing thrombin and has higher affinity to dermatan sulfate on the surface of vascular smooth muscle cells. Therefore, it is regarded as an extravascular antithrombin. Clinical evidence that these regulatory factors function as natural anticoagulants derives from the observation of patients with congenital deficiency of each factor suffering from severe venous and anterial thrombosis.(ABSTRACT TRUNCATED AT 250 WORDS)

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The short-term effects of low-density lipoprotein (LDL) apheresis using a dextran sulfate-cellulose (DSC) column equipped with a plasma separator using a polysulfone (PS) membrane filter on the serum total cholesterol, lipoprotein(a) (Lp(a)), C4b binding protein (C4bp), protein C and protein S and complement components levels were examined in a patient with familial hypercholesterolemia (heterozygote, type IIa). PS/DSC-LDL apheresis markedly lowered the total cholesterol by 69.9 +/- 2.9%, serum Lp(a) level by 80.2 +/- 3.4%, and C4bp by 81.1 +/- 2.5% after 8 apheresis sessions. All the above parameters gradually returned to the baseline levels within 10 days. The free protein S level was not significantly changed, while the C4bp/protein S complex level was markedly decreased relative to the decrease in C4bp. The protein C level was moderately reduced by 29%. Almost all serum complements and complement co-factors as well as C4bp were moderately to markedly decreased after LDL apheresis, but returned to the initial levels within a few days. PS/DSC-LDL apheresis effectively eliminated both serum LDL and Lp(a), and did not have an adverse effect on fibrinolysis or complement cascade in the blood.

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The authors measured serum neopterin by HPLC in 3 patients with hemophagocytic histiocytosis (HH) with DIC which occurred during the clinical course of T cell malignant lymphoma (T-ML). Extremely high levels of serum neopterin (754.3 +/- SD 467.3 pmol/ml) were found in the patients, about 200, 13 and 10 times higher than that of normal subjects, non-HH DIC patients and non-HH/DIC T-ML patients. Moreover their serum soluble interleukin-2 receptor levels were markedly elevated. These results indicate that markedly raised serum neopterin would be a sensitive parameter for activation of the mononuclear phagocyte system closely associated with T-cell activation and may serve as a useful diagnostic marker for HH.

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Antithrombotic effect of recombinant human thrombomodulin (TM) on experimentally induced thrombosis in mice was studied. The soluble recombinant human TM (TMD 123), which was expressed in Chinese hamster ovary cells and purified from the conditioned medium, prolonged thrombin clotting time for mouse plasma in a dose-dependent fashion. Thrombosis was induced by the injection of lipopolysaccharide (LPS) from E. coli into a lateral tail vein of mice and was identified as disseminated intravascular coagulation (DIC) syndrome by hematological and histological examinations. Simultaneous injection of TMD 123 with LPS into another lateral tail vein of mice significantly corrected the hematological abnormalities compatible with DIC, and also corrected the histological abnormalities i. e. fibrin deposition and decrease of cellular TM in the target organs including kidney, liver and lung. These results indicate that recombinant human TM is a potent antithrombotic agent and that this would be an expectative anticoagulant for DIC or thrombosis in man.

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The immunocytochemical study of thrombomodulin (TM), a newly recognized anticoagulant endothelial surface protein, was performed with a surgical specimen of a superficial temporal artery (STA) obtained from a 29-year-old woman with familial moyamoya disease. The staining of TM showed positive immunoreactivity in smaller vessels in the surrounding connective tissue of the specimen, whereas negative in STA. Immunoelectronmicroscopically the luminal plasma membrane of endothelial cells was positive for TM. These staining pattern was the same as that in controls. She concurrently suffered from von Willebrand disease type I, and she had two cerebral hemorrhagic attacks. A quantitative defect of the von Willebrand factor in the endothelium was demonstrated immunocytochemically.

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In order to elucidate the prevalence of von Willebrand factor (vWF) deficiency state, we investigated plasma vWF levels among 343 patients with bleeding tendency, 465 patients without bleeding tendency and 704 random unrelated normals living in Kagoshima prefecture. The prevalence of symptomatic vWF deficiency state was at least 2.3 per 100,000 of the population, and that of asymptomatic one in healthy individuals was 1.3%. These results indicate that the overall incidence of vWF deficient state in general population would be considerably higher than that previously reported.

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The gene coding for plasminogen has been compared with several abnormal genes from Japanese patients by the polymerase chain reaction and DNA sequence analysis. Two types of abnormal genes coding for plasminogen were identified in these patients. In the type I mutation, a guanosine in GCT coding for Ala-601 near the active-site histidine was replaced by an adenosine resulting in ACT coding for threonine. This mutation was also shown by the loss of a cleavage site for Fnu4HI endonuclease, a restriction enzyme that recognizes GCTGC but not ACTGC. In the type II mutation, a guanosine in GTC coding for Val-355 was replaced by a thymidine resulting in TTC coding for phenylalanine. This change was readily shown by digestion with Ava II endonuclease, a restriction enzyme that recognizes GGTCC and not GTTCC. The type I mutation has been found to be identical to a plasminogen variant identified in Japanese patients by amino acid sequence analysis and also detected by isoelectric focusing, whereas the type II mutation is a unique amino acid substitution in the connecting region between the third and fourth kringles in plasminogen. DNA sequence analysis also revealed that the abnormal genes carry several silent nucleotide substitutions located primarily within introns and 5' and 3' flanking regions.

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A family with two complex disorders of hemostasis, von Willebrand disease (vWD) and hypofibrinogenemia was reported. The probands were 21- and 16-year-old full brothers suffering from serious bleeding tendencies from childhood. The elder brother had a subarachnoid hemorrhage at the age of 15. The younger brother had repeated episodes of gastrointestinal bleedings since he was 10 years of age. Coagulation studies revealed that both of them had almost the same hemostatic abnormalities, i.e. severe vWD, 9 to 12% of plasma vWF levels, and mild hypofibrinogenemia, 125 to 130 mg/dl of plasma fibrinogen levels. Multimeric compositions of their vWF were normal, and functional assay for fibrinogen concentration yielded essentially the same values as did immunologic assay. These results indicated that they had two complex disorders, extreme type I vWD and heterozygous state of afibrinogenemia resulting in serious bleeding tendency. Family study showed that these two hemostatic disorders were paternal inheritance, and it was strongly postulated that vWD and hypofibrinogenemia might be highly-combined hemostatic disorders.

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Previously, we reported a case of 26-year-old woman with a mild bleeding tendency whose platelets specifically lacked collagen-induced aggregation and adhesion to collagen fibrils. In this report, we investigated the membrane glycoproteins of this patient's platelets and found that her platelets were absent in a 61-kDa glycoprotein, which was identified to be glycoprotein VI (GP VI) of the platelet membrane. Her parents platelets contained about 50% the normal amount of GP VI. These results indicate that our patient has a congenital homozygous GP VI deficiency and that GP VI functions as a collagen receptor.

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Occurrence of the two congenital hemorrhagic disorders, von Willebrand disease (vWD) and hemophilia A, was found in the same family. The propositus was a 21-year-old male patient with findings of moderate hemophilia A. Father, the eldest sister and second eldest sister were found to have mild type I vWD. Mother was confirmed to be a hemophilia A carrier, and the eldest son of second eldest sister to be a moderate hemophilia A. These results suggest that the occurrence of the two hemorrhagic disorders may have been resulted from the incidental mating of father's vWD gene and mother's hemophilia A gene, and suggest that second eldest sister may be the double heterozygosity of type I vWD and hemophilia A.

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We reported a 34-year-old female patient with refractory idiopathic thrombocytopenic purpura (ITP) in whom a subacute subdural hematoma occurred without any preceding trauma during danazol administration which resulted in a marked decrease of plasma fibrinogen level. It is strongly suggested that danazol should be very carefully administered in ITP patients with serious bleeding tendency.

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A very rare case with coincidental idiopathic thrombocytopenic purpura (ITP) and familial von Willebrand disease (vWD) was reported. A 23-year-old female was admitted because of unusual bleeding tendency lasting still after the remission of thrombocytopenic state associated with ITP. Coagulation studies indicated the presence of a mild vWD, which was thought to be responsible for the bleeding tendency. The qualitative analysis of von Willebrand factor by crossed immunoelectrophoresis and SDS-1.2% agarose gel electrophoresis showed normal multimeric composition compatible with type I vWD. vWF-inhibitor was negative, and family study revealed that her mother was also affected with type I vWD. These results suggested that there was no immediate causal relation between the two disease states. The prevalence of concomitant disease states with ITP and vWD was discussed.

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Molecular level studies on platelets deficient in collagen-induced aggregation provide evidence for identifying possible platelet collagen receptors. We investigated platelets from a patient with mild bleeding time prolongation, but otherwise normal coagulation data. Her platelets lacked collagen-induced aggregation and adhesion, but retained normal aggregation and release by other agonists. Labeling her platelets with 125I or 3H and analysis by SDS-PAGE/autoradiography showed normal levels of glycoproteins Ia, Ib, IIa, IIb, IIIa, and IV. However, there were significantly decreased incorporations of both radioactivities into a 61-kD membrane glycoprotein (GP), which was identified as GPVI from its mobility on unreduced-reduced, two-dimensional SDS-PAGE. Sugiyama et al. (1987. Blood. 69: 1712) reported that the serum from an idiopathic thrombocytopenic purpura (ITP) patient contained an antibody against a 62-kD platelet protein. Our patient's platelets lacked the antigen for the ITP patient's antibody, demonstrating that the ITP serum contains a specific antibody against GPVI. The patient's parents' platelets contained approximately 50% the normal amount of GPVI, but still had normal collagen-induced aggregation and adhesion. The patient's platelets did not bind to types I and III collagen fibrils. Our results suggest that GPVI functions as a collagen receptor.

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