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Anti-CD19 chimeric antigen receptor T (CAR-T) cell therapy has facilitated progress in treatment of refractory/relapsed diffuse large B-cell lymphoma (DLBCL). A well-known adverse event after CAR-T therapy is cytokine release syndrome(CRS). However, the etiology and pathophysiology of CRS-related coagulopathy remain unknown. Therefore, we conducted a prospective cohort study to comprehensively analyze coagulation/ fibrinolysis parameters present in peripheral blood of adult DLBCL patients treated with tisagenlecleucel in a single institution. Samples were collected from 25 patients at 3 time points: before lymphocyte-depletion chemotherapy and on days 3 and 13 after CAR-T infusion. After infusion, all patients except 1 experienced CRS, and 13 required the administration of tocilizumab. A significant elevation in the plasma level of total plasminogen activator inhibitor 1 (PAI-1), which promotes the initial step of coagulopathy (mean, 22.5 ng/mL before lymphocyte-depletion and 41.0 on day 3, P = .02), was observed at the onset of CRS. Moreover, this suppressed fibrinolysis-induced relatively hypercoagulable state was gradually resolved after CRS remission with normalization of total PAI-1 to preinfusion levels without any organ damage (mean values of soluble fibrin: 3.16 µg/mL at baseline, 8.04 on day 3, and 9.16 on day 13, P < .01; and mean PAI-1: 25.1 ng/mL on day 13). In conclusion, a hypofibrinolytic and relatively hypercoagulable state concomitant with significant total PAI-1 elevation was observed at the onset of CRS even in DLBCL patients with mild CRS. Our results will facilitate understanding of CRS-related coagulopathy, and they emphasize the importance of monitoring sequential coagulation/fibrinolysis parameters during CAR-T therapy., キメラ抗原受容体T細胞療法による血液凝固と線溶の変動を解析 --サイトカイン放出症候群に伴う凝固障害の病態解析にむけて--. 京都大学プレスリリース. 2022-06-20.

Key Clinical Message This report demonstrates that not only heparin‐induced thrombocytopenia, but also hemodialysis conditions (platelet activation due to hemodiafiltration and heparin underdosing) may markedly reduce the platelet count and cause clotting in the hemodialysis circuit in patients in a hypercoagulable state. The clot prevention effects of bortezomib are therefore of great importance.

X-linked sideroblastic anemia (XLSA) is associated with mutations in the erythroid-specific δ-aminolevulinic acid synthase (ALAS2) gene. Treatment for XLSA is mainly supportive, except in pyridoxine-responsive patients. Female XLSA often represents a late onset of severe anemia, mostly due to the acquired skewing of X-chromosome inactivation. Here, we successfully generated active wild-type and mutant ALAS2 induced pluripotent stem cell (iPSC) lines from the peripheral blood cells of an affected mother and two daughters in a family with pyridoxine-resistant XLSA due to a heterozygous ALAS2 missense mutation (R227C). The erythroid differentiation potential was severely impaired in active mutant iPSC lines compared to that in active wild-type iPSC lines. Most of the active mutant iPSC-derived erythroblasts revealed an immature morphological phenotype, and some showed dysplasia and perinuclear iron deposits. Additionally, globin and HO-1 expression and heme biosynthesis in active mutant erythroblasts were severely impaired compared to that in active wild-type erythroblasts. Furthermore, genes associated with erythroblast maturation and karyopyknosis showed significantly reduced expression in active mutant erythroblasts, recapitulating the maturation defects. Notably, the erythroid differentiation ability and hemoglobin expression of active mutant iPSC-derived hematopoietic progenitor cells (HPCs) were improved by the administration of δ-aminolevulinic acid, verifying the suitability of the cells for drug testing. Administration of a DNA demethylating agent, azacitidine, reactivated the silent wild-type ALAS2 allele in active mutant HPCs and ameliorated erythroid differentiation defects, suggesting that azacitidine is a potential novel therapeutic drug for female XLSA. Our patient-specific iPSC platform provides novel biological and therapeutic insights for XLSA., 女性のX連鎖性鉄芽球性貧血患者さん由来のiPS細胞を使った病態モデルの作製と治療薬候補の発見. 京都大学プレスリリース. 2021-12-01.

Introduction While white blood cell (WBC) parameters have been suggested to depend on ethnicity and gender, reference intervals in healthy Asian populations are limited. The present study established reference intervals of WBC parameters for healthy adults in Japan. Methods A total of 750 healthy adults (447 women and 303 men; 18-67 years old, median 40 years old) at 7 Japanese centers who participated in regular medical checkups entered this study. The WBC parameters were measured using automated hematocytometers and blood film reviews by a manual microscopic examination. Results The reference intervals of the WBC parameters according to gender in healthy adults were determined. Age-specific decreases in WBC counts of both gender groups and in neutrophil counts of women were noted. Favorable correlations between the hematocytometer and microscopic methods were found in neutrophils, lymphocytes, and eosinophils but not in monocytes or basophils. Conclusion This study suggests the need to consider gender and age in the clinical use of reference intervals of WBC parameters.

Thrombomodulin (TM) is an endothelial receptor for thrombin. The thrombin-thrombomodulin complex activates protein C in the anticoagulant pathway. Soluble TM is thought to be a marker for endothelial cell damage. We have evaluated the analytical performance of the HISCL TM test, a chemiluminescent enzyme immunoassay that measures soluble TM using biotinylated thrombomodulin monoclonal antibodies on Sysmex HISCL-2000i analyzer. Within-run coefficient of variation (CV) for control samples with low and high TM levels were 1.67% and 1.95% whereas between-run CVs for the control samples were 2.18% and 3.25% respectively. The assay showed excellent dilution linearity up to a TM level of 198 TU/mL with the lower limit of detection of 0.34 TU/mL. There was no effect of interfering substances on TM measurements. Results obtained on 362 patients showed that for those patients with a high TM level, C-reactive protein (CRP), fibrinogen (FIB), D-dimer, thrombin-antithrombin complex (TAT) and plasmin-α2 plasmin inhibitor complex (PIC) levels were significantly higher than in those patients with a normal TM level, and glomerular filtration rates (eGFR) were significantly lower than in those patients with a normal TM level. It was also observed that patients with high TM levels have significantly higher levels of von Willebrand factor antigen (vWFAg) and ristocetin cofactor activity (vWFRCo) which are associated with marked endothelial dysfunction. This study demonstrates that the HISCL TM test fulfils the analytical performance requirements for routine laboratory testing and an increased TM level detected is a useful indicator of endothelial dysfunction.

Functional fibrinogen concentration of a male infant showed0.50 g/l and we speculated this patient as a dysfibrinogenemia or hypofibrinogenemia.We analyzed propositus and his parent by DNA sequencing and by thrombin-catalyzed fibrin polymerization for purified plasma fibrinogen.Although functional fibrinogen determinations based on Clauss method showed the marked discrepancy of values among 3 sets of reagent and analyzer, we found a novel heterozygous variant fibrinogen, Kyoto IV, caused by 3-bp deletion in Bbeta-chain gene corresponding to the deletion of 111Ser located in coiled-coil region. We suggested that the discrepancy of fibrinogen values among 3 assays was caused by the difference in NaCl concentration in reagents for determination and analyzed the polymerization under the conditions of various NaCl concentrations. Although under normal physiological conditions Kyoto IV fibrinogen augmented the polymerization as compared with normal control, in 0.21 mol/l NaCl Kyoto IV fibrinogen showed abruptly impaired polymerization curve compared with normal control.Variant fibrinogen, BbetaDelta111Ser, showed augmented lateral aggregation under normal physiological conditions and the residue located in coiled-coil region, Bbeta111Ser, plays an important role in the lateral aggregation.