Chronic hepatitis E mostly occurs in organ transplant recipients and can lead to rapid liver fibrosis and cirrhosis. Previous studies found that the development of chronic hepatitis E virus (HEV) infection is linked to the type of immunosuppressant used. Animal models are crucial for the study of pathogenesis of chronic hepatitis E. We previously established a stable chronic HEV infection rabbit model using cyclosporine A (CsA), a calcineurin inhibitor (CNI)-based immunosuppressant. However, the immunosuppression strategy and timing may be optimized, and how different types of immunosuppressants affect the establishment of chronic HEV infection in this model is still unknown. Here, we showed that chronic HEV infection can be established in 100% of rabbits when CsA treatment was started at HEV challenge or even 4 weeks after. Tacrolimus or prednisolone treatment alone also contributed to chronic HEV infection, resulting in 100% and 77.8% chronicity rates, respectively, while mycophenolate mofetil (MMF) only led to a 28.6% chronicity rate. Chronic HEV infection was accompanied with a persistent activation of innate immune response evidenced by transcriptome analysis. The suppressed adaptive immune response evidenced by low expression of genes related to cytotoxicity (like perforin and FasL) and low anti-HEV seroconversion rates may play important roles in causing chronic HEV infection. By analyzing HEV antigen concentrations with different infection outcomes, we also found that HEV antigen levels could indicate chronic HEV infection development. This study optimized the immunosuppression strategies for establishing chronic HEV infection in rabbits and highlighted the potential association between the development of chronic HEV infection and immunosuppressants.IMPORTANCEOrgan transplant recipients are at high risk of chronic hepatitis E and generally receive a CNI-based immunosuppression regimen containing CNI (tacrolimus or CsA), MMF, and/or corticosteroids. Previously, we established stable chronic HEV infection in a rabbit model by using CsA before HEV challenge. In this study, we further optimized the immunosuppression strategies for establishing chronic HEV infection in rabbits. Chronic HEV infection can also be established when CsA treatment was started at the same time or even 4 weeks after HEV challenge, clearly indicating the risk of progression to chronic infection under these circumstances and the necessity of HEV screening for both the recipient and the donor preoperatively. CsA, tacrolimus, or prednisolone instead of MMF significantly contributed to chronic HEV infection. HEV antigen in acute infection phase indicates the development of chronic infection. Our results have important implications for understanding the potential association between chronic HEV infection and immunosuppressants.

Calcineurin, protein phosphatase 2B (PP2B) or protein phosphatase 3 (PP3), is a calcium-dependent serine/threonine protein phosphatase. Calcineurin is widely expressed in the kidney and regulates renal Na+ and K+ transport. In the thick ascending limb, calcineurin plays a role in inhibiting NKCC2 function by promoting the dephosphorylation of the cotransporter and an intracellular sorting receptor, called sorting-related-receptor-with-A-type repeats (SORLA), is involved in modulating the effect of calcineurin on NKCC2. Calcineurin also participates in regulating thiazide-sensitive NaCl-cotransporter (NCC) in the distal convoluted tubule. The mechanisms by which calcineurin regulates NCC include directly dephosphorylation of NCC, regulating Kelch-like-3/CUL3 E3 ubiquitin-ligase complex, which is responsible for WNK (with-no-lysin-kinases) ubiquitination, and inhibiting Kir4.1/Kir5.1, which determines NCC expression/activity. Finally, calcineurin is also involved in regulating ROMK (Kir1.1) channels in the cortical collecting duct and Cyp11 2 expression in adrenal zona glomerulosa. In summary, calcineurin is involved in the regulation of NKCC2, NCC, and inwardly rectifying K+ channels in the kidney, and it also plays a role in modulating aldosterone synthesis in adrenal gland, which regulates epithelial-Na+-channel expression/activity. Thus, application of calcineurin inhibitors (CNIs) is expected to abrupt calcineurin-mediated regulation of transepithelial Na+ and K+ transport in the kidney. Consequently, CNIs cause hypertension, compromise renal K+ excretion, and induce hyperkalemia.

Calcineurin inhibitors (CNIs) constitute the backbone of modern acute graft-versus-host disease (aGVHD) prophylaxis regimens but have limited efficacy in the prevention and treatment of chronic GVHD (cGVHD). We investigated the effect of CNIs on immune tolerance after stem cell transplantation with discovery-based single-cell gene expression and T cell receptor (TCR) assays of clonal immunity in tandem with traditional protein-based approaches and preclinical modeling. While cyclosporin and tacrolimus suppressed the clonal expansion of CD8+ T cells during GVHD, alloreactive CD4+ T cell clusters were preferentially expanded. Moreover, CNIs mediated reversible dose-dependent suppression of T cell activation and all stages of donor T cell exhaustion. Critically, CNIs promoted the expansion of both polyclonal and TCR-specific alloreactive central memory CD4+ T cells (TCM) with high self-renewal capacity that mediated cGVHD following drug withdrawal. In contrast to posttransplant cyclophosphamide (PT-Cy), CSA was ineffective in eliminating IL-17A-secreting alloreactive T cell clones that play an important role in the pathogenesis of cGVHD. Collectively, we have shown that, although CNIs attenuate aGVHD, they paradoxically rescue alloantigen-specific TCM, especially within the CD4+ compartment in lymphoid and GVHD target tissues, thus predisposing patients to cGVHD. These data provide further evidence to caution against CNI-based immune suppression without concurrent approaches that eliminate alloreactive T cell clones.

Transplantation-associated thrombotic microangiopathy (TA-TMA) is a well-recognized serious complication of hematopoietic stem cell transplantation (HSCT). The understanding of TA-TMA pathophysiology has expanded in recent years. Dysregulation of the complement system is thought to cause endothelial injury and, consequently, microvascular thrombosis and tissue damage. TA-TMA can affect multiple organs, and each organ exhibits specific features of injury. Central nervous system (CNS) manifestations of TA-TMA include posterior reversible encephalopathy syndrome, seizures, and encephalopathy. The development of neurological dysfunction is associated with a significantly lower overall survival in patients with TA-TMA. However, there are currently no established histopathological or radiological criteria for the diagnosis of CNS TMA. Patients who receive total body irradiation (TBI), calcineurin inhibitors (CNI), and severe acute and chronic graft-versus-host disease (GVHD) are at a high risk of experiencing neurological complications related to TA-TMA and should be considered for directed TA-TMA therapy. However, the incidence and clinical manifestations of TA-TMA neurotoxicity remain unclear. Studies specifically examining the involvement of CNS in TMA syndromes are limited. In this review, we discuss clinical manifestations and imaging abnormalities in patients with nervous system involvement in TA-TMA. We summarize the mechanisms underlying TA-TMA and its neurological complications, including endothelial injury, evidence of complement activation, and treatment options for TA-TMA.

OBJECTIVE: Recent case reports have drawn attention to the emergence of acute pancreatitis, a potentially life-threatening complication associated with tacrolimus. This study uses the Food and Drug Administration Adverse Event Reporting System (FAERS) to investigate the risk signal of acute pancreatitis associated with calcineurin inhibitors (CNIs), with a focus on tacrolimus.
METHODS: We conducted an observational retrospective pharmacovigilance study utilizing the FAERS database, encompassing data from its inception to the third quarter of 2023. The assessment of the association between CNIs and acute pancreatitis was carried out using the Information Component (IC) and Reporting Odds Ratio (ROR). Logistic regression analysis was employed to elucidate factors contributing to fatal outcomes. All analyses were performed using R version 3.2.5.
RESULTS: We identified 221 cases of acute pancreatitis linked to CNIs. The median age of individuals experiencing acute pancreatitis induced by tacrolimus was 43, with a predominant occurrence among male patients. Our study showed a significant association between CNIs and acute pancreatitis (ROR 1.82 [1.60-2.08], IC 0.85 [3.66-3.92]). Comparing tacrolimus and cyclosporine, the signal for tacrolimus seemed to be higher. Further analysis revealed that, with the exception of patients aged 60 and above, the signal for tacrolimus remained stable. Contrastingly, the signal for cyclosporine was unstable and limited to the male group and individuals aged less than 20 years. In cases of CNIs-related acute pancreatitis, the mortality rate was 31.67% (70/221 cases). Logistic regression analysis indicated that a younger age acts as a protective factor for death due to CNIs-related acute pancreatitis (OR 0.943, 95% CI 0.915-0.972, P = 0.000).
CONCLUSIONS: Our study has identified a safety signal for tacrolimus in relation to acute pancreatitis. Additionally, we observed advanced age as a significant risk factor for tacrolimus-related acute pancreatitis, leading to mortality. Given the widespread use of tacrolimus, it is crucial for healthcare providers to be vigilant and informed about the potential association with acute pancreatitis.

This study examines the association of standard-of-care systemic lupus erythematosus (SLE) medications with key outcomes such as low disease activity attainment, flares, damage accrual, and steroid-sparing, for which there is current paucity of data.
The Asia Pacific Lupus Collaboration (APLC) prospectively collects data across numerous sites regarding demographic and disease characteristics, medication use, and lupus outcomes. Using propensity score methods and panel logistic regression models, we determined the association between lupus medications and outcomes.
Among 1707 patients followed over 12,689 visits for a median of 2.19 years, 1332 (78.03%) patients achieved the Lupus Low Disease Activity State (LLDAS), 976 (57.18%) experienced flares, and on most visits patients were taking an anti-malarial (69.86%) or immunosuppressive drug (76.37%). Prednisolone, hydroxychloroquine and azathioprine were utilised with similar frequency across all organ domains; methotrexate for musculoskeletal activity. There were differences in medication utilisation between countries, with hydroxychloroquine less frequently, and calcineurin inhibitors more frequently, used in Japan. More patients taking leflunomide, methotrexate, chloroquine/hydroxychloroquine, azathioprine, and mycophenolate mofetil/mycophenolic acid were taking ≤ 7.5 mg/day of prednisolone (compared to > 7.5 mg/day) suggesting a steroid-sparing effect. Patients taking tacrolimus were more likely (Odds Ratio [95% Confidence Interval] 13.58 [2.23-82.78], p = 0.005) to attain LLDAS. Patients taking azathioprine (OR 0.67 [0.53-0.86], p = 0.001) and methotrexate (OR 0.68 [0.47-0.98], p = 0.038) were less likely to attain LLDAS. Patients taking mycophenolate mofetil were less likely to experience a flare (OR 0.79 [0.64-0.97], p = 0.025). None of the drugs was associated with a reduction in damage accrual.
This study suggests a steroid-sparing benefit for most commonly used standard of care immunosuppressants used in SLE treatment, some of which were associated with an increased likelihood of attaining LLDAS, or reduced incidence of flares. It also highlights the unmet need for effective treatments in lupus.

Alzheimer\'s disease is a progressive neurodegenerative disorder characterized by impairments in synaptic plasticity and cognitive performance. Current treatments are unable to achieve satisfactory therapeutic effects or reverse the progression of the disease. Calcineurin has been implicated as part of a critical signaling pathway for learning and memory, and neuronal calcineurin may be hyperactivated in AD. To investigate the effects and underlying mechanisms of FK506, a calcineurin inhibitor, on Alzheimer-like behavior and synaptic dysfunction in the 3 × Tg-AD transgenic mouse model of Alzheimer\'s disease, we investigated the effect of FK506 on cognitive function and synaptic plasticity in the 3 × Tg-AD transgenic mouse model of Alzheimer\'s disease. The results showed that FK506 treatment ameliorated cognitive deficits, as indicated by the decreased latency in the water maze, and attenuated tau hyperphosphorylation in 3 × Tg-AD mice. Treatment with FK506 also reduced the levels of certain markers of postsynaptic deficits, including PSD-95 and NR2B, and reversed the long-term potentiation deficiency and dendritic spine impairments in 3 × Tg-AD mice. These findings suggest that treatment with calcineurin inhibitors such as FK506 can be an effective therapeutic strategy to rescue synaptic deficit and cognitive impairment in familial Alzheimer\'s disease and related tauopathies.

OBJECTIVE: To describe the pharmacokinetic (PK) characteristics of nirmatrelvir/ritonavir in renal transplant recipients and explore the potential factors that related to the PK variance of nirmatrelvir/ritonavir and its interaction with calcineurin inhibitor (CNI).
METHODS: Renal transplant recipients treated with CNI and nirmatrelvir/ritonavir were prospectively enrolled. Steady-state plasma concentrations of nirmatrelvir/ritonavir were determined by high-performance liquid chromatography-tandem mass spectrometry, and the PK parameters were calculated using non-compartmental analysis. Spearman correlation analysis was used for exploring influencing factors.
RESULTS: A total of eight recipients were enrolled; for nirmatrelvir and ritonavir, AUC/dose was 0.24179 ± 0.14495 and 0.06196 ± 0.03767 μg·h·mL-1·mg-1. Red blood cell (RBC), hematocrit (Ht), hemoglobins (Hb), and creatinine clearance (Ccr) were negatively correlated with AUC/dose of nirmatrelvir, while Ccr, CYP3A5 genotype, and CYP3A4 genotype were related to the AUC/dose of ritonavir. Ccr was negatively correlated with the C0/dose of tacrolimus (TAC) after termination of nirmatrelvir/ritonavir (rs =  -0.943, p = 0.008).
CONCLUSIONS: The PK characteristics of nirmatrelvir/ritonavir vary greatly among renal transplant recipients. Factors including Ccr and CYP3A5 genotype were related to the in vivo exposure of nirmatrelvir/ritonavir. During the whole process before and after nirmatrelvir/ritonavir therapy, it is recommended to adjust the CNI basing on renal function to avoid CNI toxicity exposure.

The effect of Ryanodine receptor2 (RyR2) and its stabilizer on cardiac hypertrophy is not well known. C57/BL6 mice underwent transverse aortic contraction (TAC) or sham surgery were administered dantrolene, the RyR2 stabilizer, or control drug. Dantrolene significantly alleviated TAC-induced cardiac hypertrophy in mice, and RNA sequencing was performed implying calcineurin/NFAT3 and TNF-α/NF-κB/NLRP3 as critical signaling pathways. Further expression analysis and Western blot with heart tissue as well as neonatal rat cardiomyocyte (NRCM) model confirmed dantrolene decreases the activation of calcineurin/NFAT3 signaling pathway and TNF-α/NF-κB/NLRP3 signaling pathway, which was similar to FK506 and might be attenuated by calcineurin overexpression. The present study shows for the first time that RyR2 stabilizer dantrolene attenuates cardiac hypertrophy by inhibiting the calcineurin, therefore downregulating the TNF-α/NF-κB/NLRP3 pathway.

Objectives: To investigate the efficacy of short-term substitution of recombinant humanized anti-CD25 monoclonal antibody (Basiliximab) as acute GVHD (aGVHD) prophylaxis in calcineurin inhibitors (CNI) intolerant patients following allogeneic hematopoietic stem cell transplantation (allo-HSCT) . Methods: This study included 17 patients with refractory malignant hematological disorders who underwent salvage allo-HSCT at the Bone Marrow Transplantation Department of Shanghai Zhaxin Traditional Chinese and Western Medicine Hospital from August 2021 to August 2022 and were treated with Baliximab to prevent aGVHD due to severe adverse reactions to CNI. There were seven men and ten women, with a median age of 43 years (18-67). Following the discontinuation of CNI, Basiliximab was administered at a dose of 1 mg/kg once weekly until CNI or mTOR inhibitors were resumed. Results: Basiliximab was started at an average of 5 (1-32) days after HSCT. The median duration of substitution was 20 (7-120) days. All had neutrophil engraftment within a median of 12 (10-17) days. Thirteen patients had platelet engraftment after a median of 13 (11-20) days. Four patients did not develop stable platelet engraftment. Eight patients (47.1% ) developed Grade Ⅱ-Ⅳ aGVHD, while four (23.6% ) developed Grade Ⅲ/Ⅳ aGVHD. Only one patient died from aGVHD. Before the end of the followup period, seven of 17 patients died. The longest followup period of the survivors was 347 days, and the median survival rate was not met. The overall survival (OS) rate at six months was 62.6%. Among the 17 patients, 13 (76.4% ) experienced cytomegalovirus reactivation, 7 (41.2% ) experienced EB virus activation, and no cytomegalovirus disease was observed. Conclusions: When CNI intolerance occurs during allo-HSCT, short-term replacement with Baliximab can be used as an alternative to prevent aGVHD.
目的： 探讨在钙调蛋白抑制剂（CNI）不耐受患者中短期应用重组抗CD25人源化单克隆抗体巴利昔单抗（Basiliximab）单药预防异基因造血干细胞移植（allo-HSCT）后急性移植物抗宿主病（GVHD）的有效性。 方法： 本研究纳入2021年8月至2022年8月在上海闸新中西医结合医院骨髓移植科行挽救性allo-HSCT后因CNI严重不良反应而应用巴利昔单抗预防急性GVHD的17例难治性恶性血液病患者。男7例，女10例，中位年龄43（18～67）岁。停用CNI后，给予巴利昔单抗1 mg/kg每周1次进行替代预防，直至患者有条件重新启用CNI或哺乳动物雷帕霉素靶体蛋白（mTOR）抑制剂。 结果： 巴利昔单抗的替代预防中位开始时间为移植后5（1～32）d，替代治疗中位持续时间为20（7～120）d。所有患者均获得粒细胞植入，中位植入时间12（10～17）d。13例患者获得血小板植入，中位植入时间13（11～20）d。8例（47.1%）患者发生Ⅱ～Ⅳ度急性GVHD，4例（23.6%）发生Ⅲ/Ⅳ度急性GVHD。仅有1例患者死于急性GVHD。至随访截止，17例患者中7例死亡，存活患者中随访最长时间为347 d，中位生存时间未达到，移植后6个月总生存率为62.6%。17例患者中，13例（76.4%）发生巨细胞病毒再激活，7例（41.2%）发生EB病毒激活，未发生巨细胞病毒病。 结论： 在allo-HSCT过程中出现CNI不耐受时，短期单药应用巴利昔单抗可作为急性GVHD的替代预防方案。.