中川 理恵

This study investigated the anti-tumor effects of andrographolide, a diterpene lactone derived from Andrographis paniculata, on T-cell acute lymphoblastic leukemia (T-ALL) cells. Andrographolide induced dose-dependent cytotoxicity and morphological changes in the T-ALL cell line Jurkat cells, including cell shrinkage and chromatin condensation. Mechanistically, andrographolide triggers apoptosis through reactive oxygen species (ROS) generation, mitochondrial membrane depolarization, and cytochrome c release. These effects were reversed by the ROS inhibitor N-acetyl-L-cysteine (NAC), indicating that andrographolide induces apoptosis through a ROS-dependent apoptotic pathway. In contrast, NAC treatment did not reverse cytarabine- and vincristine-induced apoptosis or the ROS-dependent apoptotic pathway in Jurkat cells. Intriguingly, andrographolide also induced ferroptosis, as evidenced by increased expression of the ferroptosis marker fatty acid-CoA ligase 4 and ultrastructural changes such as reduced mitochondrial area and disappearance of cristae. These effects were likewise reversed by NAC, further implicating ROS in the ferroptotic process. In MOLT-4 cells, where andrographolide suppressed viability, increased Annexin V positivity and ROS levels, and upregulated FACL4 expression in a NAC-sensitive manner. Unlike cytarabine and vincristine, andrographolide did not significantly alter cell cycle distribution. In conclusion, andrographolide induces both apoptosis and ferroptosis in T-ALL cells via ROS-dependent mechanisms that are distinct from those of conventional chemotherapeutic agents. These dual actions position andrographolide as a candidate for standalone or combination therapy in T-ALL.

BACKGROUND: Ethylenediamine tetraacetate/glycine acid (EGA) and chloroquine diphosphate (CDP) are used in transfusion testing to dissociate IgG antibodies from red blood cells (RBCs). However, the ability of these reagents to dissociate IgM antibodies sensitized to RBCs has not been comprehensively elucidated. We investigated whether EGA and CDP could dissociate cold-reactive antibodies from RBCs and their effect on RBCs after dissociation treatment. STUDY DESIGN AND METHODS: Cold-reactive antibody-sensitized RBC samples were prepared by mixing group A RBCs and group B plasma and treated with EGA, CDP, and dithiothreitol (DTT). Before and after the dissociation treatment, changes in the agglutination of these RBCs were assessed using the test tube method. Flow cytometric analysis was used to confirm the nature of antibodies bound to RBCs. Additionally, RBC morphology was evaluated using scanning electron microscopy. This study utilized off-label use of EGA and CDP. RESULTS: Flow cytometric analysis showed that antibodies sensitized to RBCs were mainly IgM antibodies. After antibody dissociation, agglutination disappeared in the EGA-treated samples to the same degree as in the DTT-treated samples. However, IgM antibodies remained in the CDP-treated samples. Regarding RBC morphology, RBC surface appeared coarser in both EGA- and CDP-treated samples, and RBC area was significantly smaller in the CDP-treated samples than in the EGA-treated samples. DISCUSSION: EGA could dissociate cold-reactive antibodies, whereas CDP had a higher residual antibody content. This difference in dissociation ability appears to correlate with the antibody pH of the dissociation reagent. EGA treatment may be useful in cases of sensitization by high-titer cold-reactive antibodies.

BACKGROUND: Donor-specific antibodies (DSAs) targeting human leukocyte antigens (HLAs) substantially reduce the longevity of transplanted organs. Desensitization of DSA-positive renal transplant recipients is achieved through intravenous administration of immunoglobulin (IVIg). However, the presence and detectability of anti-HLA antibodies in IVIg preparations following administration are not fully understood. We aimed to assess whether immunoglobulin preparations contain anti-HLA antibodies that can be detected as passive antibodies when administered into the body. METHODS: We evaluated 3 immunoglobulin preparations from different pharmaceutical companies, using anti-HLA class I and II antibody specificity tests and immunocomplex capture fluorescence analysis (ICFA). RESULTS: Direct testing for anti-HLA antibodies resulted in high background errors, particularly for Venoglobulin. Diluting Venoglobulin to physiological concentrations revealed the presence of anti-HLA class I antibodies; however, no common alleles were found between the specificity identification test and ICFA.For Glovenin and Venilon, anti-HLA class I and II antibodies were detected; however, variability was observed across different test reagent lots. Moreover, dilution of the globulin formulation revealed a prozone phenomenon. CONCLUSION: The administration of IVIg complicates the accurate detection of anti-HLA antibodies, underscoring the need for careful interpretation of test results post-IVIg administration.

体外式膜型人工肺（extracorporeal membrane oxygenation; ECMO）を使用する重症新型コロナウイルス感染症（COVID-19）症例は血液製剤を要するが，その使用状況についての報告は少ない。2019年11月から2021年8月までに当施設でECMO治療を受けた重症COVID-19患者19名の患者背景，血液製剤の使用量，ECMO稼働時間，臨床検査値，転帰を調査し，解析を行った。同時期にECMOを稼働した虚血性心疾患（IHD）患者18名を対照とした。ECMO稼働中，両群ともに臨床検査値の低下時とECMO離脱に際して輸血が行われていた。IHD症例ではECMO導入早期に各血液製剤が使用されていた。一方で，COVID-19症例では血液製剤が連日使用されており，特に新鮮凍結血漿（fresh frozen plasma; FFP）使用量がIHD症例と比較して有意に多かった。輸血療法の目安として臨床検査値が一般的であるが，ECMO稼働症例では両群ともにECMO離脱時にも輸血が実施されており，治療の進捗状況に留意する必要がある。輸血管理部門としては臨床検査値，治療状況を把握し輸血要請に迅速に対応できる製剤管理を行う必要がある。