All-trans retinoic acid plus low-dose rituximab vs low-dose rituximab in corticosteroid-resistant or relapsed ITP.

The study aimed to compare the efficacy and safety of all-trans retinoic acid (ATRA) plus low-dose rituximab (LD-RTX) with LD-RTX monotherapy in corticosteroid-resistant or relapsed immune thrombocytopenia (ITP) patients. Recruited patients were randomized at a ratio of 2:1 into 2 groups: 112 patients received LD-RTX plus ATRA, and 56 patients received LD-RTX monotherapy. Overall response (OR), defined as achieving a platelet count of ≥30 × 109/L confirmed on ≥2 separate occasions (≥7 days apart), at least a doubling of the baseline platelet count without any other ITP-specific treatment, and the absence of bleeding within 1 year after enrollment, was observed in more patients in the LD-RTX plus ATRA group (80%) than in the LD-RTX monotherapy group (59%) (between-group difference, 0.22; 95% CI, 0.07-0.36). Sustained response (SR), defined as maintenance of a platelet count >30 × 109/L, an absence of bleeding, and no requirement for any other ITP-specific treatment for 6 consecutive months after achievement of OR during 1 year following enrollment, was achieved by 68 (61%) patients in the combination group and 23 (41%) patients in the monotherapy group (between-group difference, 0.20; 95% CI, 0.04-0.35). The 2 most common adverse events (AEs) for the combination group were dry skin and headache or dizziness. Our findings demonstrated that ATRA plus LD-RTX significantly increased the overall and sustained response, indicating a promising treatment option for corticosteroid-resistant or relapsed adult ITP. This study is registered at www.clinicaltrials.gov as #NCT03304288.

A predictive model of herpes zoster after allogeneic hematopoietic stem cell transplantation: VZV reactivation following antiviral prophylaxis discontinuation.

Herpes zoster (HZ) refers to the rash appearing on dermatomes due to varicella zoster virus (VZV) reactivation. The incidence of HZ is significantly higher in allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients than in non-HSCT recipients. Although acyclovir prophylaxis is routinely administered to every allo-HSCT recipient for 1 year after transplantation, some individuals eventually develop late-onset HZ after completing prophylaxis. Little information is known about the clinical features of HZ after prophylactic antiviral treatment discontinuation, and an effective predictive model of late-onset HZ needs to be established. A total of 3366 patients who had received allo-HSCT from 2012 to 2017 were included in our study, among whom 201 developed HZ after 1 year (late-onset HZ). We designed a nested case-control study to identify potential predictors of late-onset HZ. Finally, we established a predictive model using binary logistic regression analysis. Age (p < .001), use of immunosuppressants at +1 year (p < .001), CD4-CD8 ratio at +1 year (p < .001), certain mental disorders (depression, anxiety, insomnia and adjustment disorder) (p < .001), engraftment time of neutrophils (p < .001), and CD8+ cell count at +30 days (p < .001) were independent predictors of late-onset HZ. A risk grading system was established based on regression coefficients. Discrimination and calibration analysis indicated that the model had good performance. We also identified several predictive factors of the incidence of HZ-related complications. This is the first scoring system for predicting the incidence of late-onset HZ after allo-HSCT. This model can be applied to identify individuals at high risk of late-onset HZ in the early period after receiving allo-HSCT.

Tacrolimus prevents complement-mediated Nod-like receptor family pyrin domain containing 3 (NLRP3) inflammasome activation and pyroptosis of mesenchymal stem cells from immune thrombocytopenia.

The abnormal immunomodulatory functions of mesenchymal stem cells (MSCs) have been implicated in the development of immune thrombocytopenia (ITP). Recent studies have suggested important effects of complement on immune cell function. However, whether complement modulates bone marrow MSCs function in ITP is poorly defined. Tacrolimus has recently been applied to the treatment of autoimmune diseases. Here, we explored whether impaired ITP-MSCs could be targeted by tacrolimus. Our results showed that the Nod-like receptor family pyrin domain containing 3 (NLRP3) inflammasome was activated in ITP MSCs with complement deposition (MSCs-C+ ) and initiated caspase-1-dependent pyroptosis. Transcriptome sequencing results showed abnormal fatty acid metabolism in MSCs-C+ . Enhanced fatty acid ß-oxidation and reactive oxygen species production activated the NLRP3 inflammasome. Adipocytes derived from MSCs-C+ secreted less adiponectin. Adiponectin promoted the differentiation of megakaryocytes and inhibited the destruction of platelets. Tacrolimus inhibited NLRP3 inflammasome activation and MSCs-C+ pyroptosis in vitro and in vivo. Tacrolimus plus danazol elicited a higher sustained response than danazol monotherapy in corticosteroid-resistant patients with ITP. Our findings demonstrate that the activation of the NLRP3 inflammasome in ITP MSCs mediated by complement could be inhibited by tacrolimus, which might be a potential new therapy for ITP.

Predicting short-term and long-term mortalities from sepsis in patients who receive allogeneic haematopoietic stem cell transplantation.

Patients who receive allogeneic haematopoietic stem cell transplantation (allo-HSCT) may develop sepsis, which result in a highly intensive care unit admission rate and mortality. Therefore, short-term and long-term prognostic models for sepsis after allo-HSCT are urgently needed. We enrolled patients receiving allo-HSCT who developed sepsis after allo-HSCT at Peking University People's Hospital between 2012 and 2021, including 287 patients who received allo-HSCT in 2018-2021 in the derivation cohort, and 337 patients in 2012-2017 in the validation cohort. Multivariate logistic regression analysis was used to identify prognostic factors, and these identified factors were incorporated into two scoring models. Seven independent factors (acute graft-versus-host disease (GVHD), chronic GVHD (cGVHD), total bilirubin, lactate dehydrogenase (LDH) and organ dysfunction [renal, lung and heart]) were included in the 6-month prognostic model, and six factors (cGVHD, C-reactive protein, LDH, organ dysfunction [lung, neurologic and coagulation]) were included in the 14-day prognostic model. The area under the receiver operating characteristic curves, calibration plots and decision curve analysis demonstrated the robust predictive performance of the models, better than the Sequential Organ Failure Assessment score. Early identification of patients with high risk of 6-month and 14-day death may allow clinicians to provide timely treatments and improve the therapeutic effects.

Recombinant human thrombopoietin increases platelet count in severe thrombocytopenic patients with hepatitis B-related cirrhosis: Multicentre real-world observational study.

Patients with hepatitis B-related cirrhosis complicated with thrombocytopenia have a higher risk of bleeding, which may lead to higher mortality. We aimed to explore the efficacy and safety of recombinant human thrombopoietin (rhTPO) in the treatment of hepatitis B-related cirrhosis complicated with severe thrombocytopenia. Patients with hepatitis B-related compensated liver cirrhosis complicated with severe thrombocytopenia were divided into four groups according to the treatment method for thrombocytopenia. Platelet counts, the appearance of bleeding symptoms and adverse events were evaluated during the observation period. Also during the observational period, the platelet counts in the prednisone group, rhTPO group and prednisone plus rhTPO group were higher than those in the no treatment group. Patients without splenomegaly reacted better to rhTPO. Fewer bleeding events of grade 2 or worse were observed in the three treatment groups compared to the no treatment group. The platelet counts at baseline and treatment with rhTPO and/or prednisone were factors associated with bleeding events of grade 2 or worse in multivariate analysis. There could be a potential advantage for the use of rhTPO plus prednisone based on higher platelet counts and fewer bleeding events. Treatment with rhTPO was more effective in patients without splenomegaly.

The glycolytic enzyme PFKFB3 determines bone marrow endothelial progenitor cell damage after chemotherapy and irradiation.

Bone marrow (BM) endothelial progenitor cell (EPC) damage of unknown mechanism delays the repair of endothelial cells (EC) and recovery of hematopoiesis after chemo-radiotherapy. We found increased levels of the glycolytic enzyme PFKFB3 in the damaged BM EPC of patients with poor graft function, a clinical model of EPC damage-associated poor hematopoiesis after allogeneic hematopoietic stem cell transplantation. Moreover, in vitro the glycolysis inhibitor 3-(3-pyridinyl)- 1-(4-pyridinyl)-2-propen-1-one (3PO) alleviated the damaged BM EPC from patients with poor graft function. Consistently, PFKFB3 overexpression triggered BM EPC damage after 5-fluorouracil treatment and impaired hematopoiesis-supporting ability in vitro. Mechanistically, PFKFB3 facilitated pro-apoptotic transcription factor FOXO3A and expression of its downstream genes, including p21, p27, and FAS, after 5-fluorouracil treatment in vitro. Moreover, PFKFB3 induced activation of NF-κB and expression of its downstream adhesion molecule E-selectin, while it reduced hematopoietic factor SDF-1 expression, which could be rescued by FOXO3A silencing. High expression of PFKFB3 was found in damaged BM EC of murine models of chemo-radiotherapy-induced myelosuppression. Furthermore, a murine model of BM EC-specific PFKFB3 overexpression demonstrated that PFKFB3 aggravated BM EC damage, and impaired the recovery of hematopoiesis after chemotherapy in vivo, effects which could be mitigated by 3PO, indicating a critical role of PFKFB3 in regulating BM EC damage. Clinically, PFKFB3-induced FOXO3A expression and NF-κB activation were confirmed to contribute to the damaged BM EPC of patients with acute leukemia after chemotherapy. 3PO repaired the damaged BM EPC by reducing FOXO3A expression and phospho-NF-κB p65 in patients after chemotherapy. In summary, our results reveal a critical role of PFKFB3 in triggering BM EPC damage and indicate that endothelial-PFKFB3 may be a potential therapeutic target for myelosuppressive injury.

PU.1 inhibition attenuates atrial fibrosis and atrial fibrillation vulnerability induced by angiotensin-II by reducing TGF-ß1/Smads pathway activation.

Fibrosis serves a critical role in driving atrial remodelling-mediated atrial fibrillation (AF). Abnormal levels of the transcription factor PU.1, a key regulator of fibrosis, are associated with cardiac injury and dysfunction following acute viral myocarditis. However, the role of PU.1 in atrial fibrosis and vulnerability to AF remain unclear. Here, an in vivo atrial fibrosis model was developed by the continuous infusion of C57 mice with subcutaneous Ang-II, while the in vitro model comprised atrial fibroblasts that were isolated and cultured. The expression of PU.1 was significantly up-regulated in the Ang-II-induced group compared with the sham/control group in vivo and in vitro. Moreover, protein expression along the TGF-ß1/Smads pathway and the proliferation and differentiation of atrial fibroblasts induced by Ang-II were significantly higher in the Ang-II-induced group than in the sham/control group. These effects were attenuated by exposure to DB1976, a PU.1 inhibitor, both in vivo and in vitro. Importantly, in vitro treatment with small interfering RNA against Smad3 (key protein of TGF-ß1/Smads signalling pathway) diminished these Ang-II-mediated effects, and the si-Smad3-mediated effects were, in turn, antagonized by the addition of a PU.1-overexpression adenoviral vector. Finally, PU.1 inhibition reduced the atrial fibrosis induced by Ang-II and attenuated vulnerability to AF, at least in part through the TGF-ß1/Smads pathway. Overall, the study implicates PU.1 as a potential therapeutic target to inhibit Ang-II-induced atrial fibrosis and vulnerability to AF.

HCMV modulates c-Mpl/IEX-1 pathway-mediated megakaryo/thrombopoiesis via PDGFRα and αvß3 receptors after allo-HSCT.

Thrombocytopenia is a common complication of human cytomegalovirus (HCMV) infection in immunocompromised hosts, which contributes to poor prognosis even in patients receiving antiviral treatment. Here, we investigated the megakaryo/thrombopoiesis process, including the involvement of the c-Mpl/IEX-1 pathway, after HCMV infection, identified receptors mediating the interaction between megakaryocytes (MKs) and HCMV, and explored novel therapeutic targets. Our data shows that HCMV directly infects megakaryocytes in patients with HCMV DNAemia and influences megakaryopoiesis via the c-Mpl/IEX-1 pathway throughout megakaryocyte maturation, apoptosis, and platelet generation in vivo and in vitro. After treatment with inhibitors of PDGFRα and αvß3, the HCMV infection rate in MKs was significantly reduced, suggesting that IMC-3G3 and anti-αvß3 are potential therapeutic alternatives for viral infection. In summary, our study proposes a possible mechanism and potential treatments for thrombocytopenia caused by HCMV infection and other viral diseases associated with abnormal hemostasis.

Prognosis and risk factors for central nervous system relapse after allogeneic hematopoietic stem cell transplantation in acute myeloid leukemia.

We performed a nested case-control study to investigate the incidence, treatment, and prognosis of central nervous system (CNS) relapse after allogenic hematopoietic stem cell transplantation (allo-HSCT) for acute myeloid leukemia (AML) and compared the outcomes of patients with CNS relapse following haploidentical donor (HID) HSCT versus identical sibling donor (ISD) HSCT. A total of 37 patients (HID-HSCT, 24; ISD-HSCT, 13) developed CNS relapse after transplantation between January 2009 and January 2019, with an incidence of 1.81%. The median time from transplantation to CNS relapse was 239 days. Pre-HSCT CNS involvement (HR 6.940, 95% CI 3.146-15.306, p < .001) was an independent risk factor for CNS relapse after allo-HSCT for AML. The 3-year overall survival (OS) for patients with CNS relapse was 60.3 ± 8.8%, which was significantly lower than that in the controls (81.5 ± 4.5%, p = .003). The incidence of CNS relapse was 1.64% for patients who received HID-HSCT and 2.55% for those who received ISD-HSCT (p = .193). There was no significant difference in OS between the HID-HSCT and ISD-HSCT subgroups among the patients with CNS relapse. In conclusion, CNS relapse is a rare but serious complication after allo-HSCT for AML, and the incidence and outcomes of patients with CNS relapse are comparable following HID-HSCT and ISD-HSCT.

Risk stratification and outcomes of intracranial hemorrhage in patients with immune thrombocytopenia under 60 years of age.

Intracranial hemorrhage (ICH) is a devastating complication of immune thrombocytopenia (ITP). However, information on ICH in ITP patients under the age of 60 years is limited, and no predictive tools are available in clinical practice. A total of 93 adult patients with ITP who developed ICH before 60 years of age were retrospectively identified from 2005 to 2019 by 27 centers in China. For each case, 2 controls matched by the time of ITP diagnosis and the duration of ITP were provided by the same center. Multivariate analysis identified head trauma (OR = 3.216, 95%CI 1.296-7.979, P =.012), a platelet count ≤ 15,000/µL at the time of ITP diagnosis (OR = 1.679, 95%CI 1.044-2.698, P =.032) and severe/life-threatening bleeding (severe bleeding vs. mild bleeding, OR = 1.910, 95%CI 1.088-3.353, P =.024; life-threatening bleeding vs. mild bleeding, OR = 2.620, 95%CI 1.360-5.051, P =.004) as independent risk factors for ICH. Intraparenchymal hemorrhage (OR = 5.191, 95%CI 1.717-15.692, P =.004) and a history of severe bleeding (OR = 4.322, 95%CI 1.532-12.198, P =.006) were associated with the 30-day outcome of ICH. These findings may facilitate ICH risk stratification and outcome prediction in patients with ITP.

Monocyte subsets in bone marrow grafts may contribute to a low incidence of acute graft-vs-host disease for young donors.

Young donors are associated with a lower cumulative incidence of acute graft-vs-host disease (aGVHD) after allogenic haematopoietic stem cell transplantation (allo-HSCT) than old donors. Although grafts are harvested from healthy donors, it is unclear whether donor age is associated with aGVHD occurrence owing to its effect on cell compositions in grafts. Moreover, the differences in monocyte subsets in grafts between young and old donors and the association between monocyte subsets in bone marrow (BM) grafts and aGVHD remain to be elucidated. In the current study, non-classical monocytes and the CD4+ /CD8+ T cell ratio were remarkably decreased in BM grafts in donors <30 years old. Multivariate analysis further revealed that the level of non-classical monocytes in BM grafts (≥0.31 × 106 /kg) was an independent risk factor for the occurrence of II-IV aGVHD. In summary, our data indicate that non-classical monocytes in BM grafts may help identify patients at high risk for aGVHD after allo-HSCT. Although further validation is required, our results suggest that the low level of non-classical monocytes and a low ratio of CD4+ /CD8+ T cell in BM grafts may be correlated with the lower incidence of aGVHD in young donors.

Frequency, Risk Factors, and Outcome of Active Tuberculosis following Allogeneic Hematopoietic Stem Cell Transplantation.

We aimed to investigate the frequency, risk factors, and outcome of active tuberculosis (TB) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). This retrospective, nested, case-control study reviewed data from 6236 patients who received allo-HSCT from January 2008 to December 2018 at a single center; thirty-three patients (0.5%) with active TB and 99 controls without active TB after allo-HSCT were identified. We performed propensity score matching by randomly selecting 3 controls for each identified active TB patient according to the time of transplantation and follow-up period. History of pretransplant active TB previously treated and inactive at time of transplantation (P< .001) was an independent risk factor. No significant differences in overall survival (P= .342), nonrelapse mortality (P= .497), or incidence of relapse (P= .807) were found. Thirty (90.9%) patients were treated with 4-drug (isoniazid, rifampicin/three rifapentine, pyrazinamide, and ethambutol) or 3-drug combination first-line therapy, with a response rate of 76.7%. Twenty-six (78.8%) patients were treated with first-line and second-line combined therapy, and the response rate was 76.9%. Five (15.2%) patients developed hepatotoxicity. In conclusion, history of pretransplant active TB previously treated and inactive at time of transplantation was an independent risk factor of active TB after allo-HSCT. No significant differences in prognosis between the TB and control groups were found. More studies are needed to help develop standardized therapeutic strategies for patients with post-transplant TB.

Incidence, Risk Factors, Outcomes, and Risk Score Model of Acute Pancreatitis after Allogeneic Hematopoietic Stem Cell Transplantation.

Acute pancreatitis (AP) has been recognized as an uncommon yet potentially lethal complication after hematopoietic stem cell transplant (HSCT). This retrospective, nested, case-control study reviewed data from 5284 consecutive patients who underwent allogeneic (allo)-HSCT between 2009 and 2018 at a single center, identifying 40 patients (0.76%) with AP after allo-HSCT. The diagnosis and severity of AP were established and classified according to existing criteria. Younger age (P = .008), grades II to IV acute graft-versus-host disease (P = .010), a history of donor lymphocyte infusion (P = .033), and pre-existing gallstones (P = .003) were independent risk factors of AP after allo-HSCT. Post-transplant AP had a trend to negatively influence overall survival (OS) and nonrelapse mortality (NRM) (P = .063) for allo-HSCT recipients, but no significant difference was found. Patients with moderately severe and severe AP had significantly lower OS (P = .002) and higher NRM (P = .000) than other patients. Based on these findings, a risk score model was also established to predict the occurrence of AP. Our risk score model performed well in terms of discrimination when applied to derivation samples. Patients were classified into a low-risk group (0 to 1 point), a medium-risk group (2 to 3 points), and a high-risk group (4 points or more). Significant difference was observed in AP incidence among the 3 groups. The predictive tool explored by our study might contribute to target high-risk patients and guide personalized AP prevention in allo-HSCT recipients.

Comparison of central nervous system relapse outcomes following haploidentical vs identical-sibling transplant for acute lymphoblastic leukemia.

To explore the incidence, risk factors, and outcomes of central nervous system (CNS) relapse after allogeneic hematopoietic stem cell transplantation (allo-HSCT) for acute lymphoblastic leukemia (ALL) and to compare the differences in CNS relapse between haploidentical donor HSCT (HID-HSCT) and HLA-identical sibling donor HSCT (ISD-HSCT). We performed a retrospective nested case-control study on patients with CNS relapse after allo-HSCT. The cumulative incidence of CNS relapse was 4.06% after allo-HSCT in ALL, with a significantly poor prognosis. The incidence was 3.91% and 5.36% in HID-HSCT and ISD-HSCT, respectively (p = .227). Among the patients with CNS relapse, the overall survival (OS) at 3 years was 56.2 ± 6.8% in the HID-HSCT subgroup and 76.9 ± 10.2% in the ISD-HSCT subgroup (p = .176). The 3-year cumulative incidence of systemic relapse was also comparable between the two subgroups (HID-HSCT, 40.6 ± 7.4%; ISD-HSCT, 13.3 ± 8.7%, respectively, p = .085). Younger age (p = .045), T-ALL (p = .035), hyperleukocytosis at diagnosis (p < .001), advanced disease stage at transplant (p < .001), pre-HSCT CNS involvement (p < .001), and absence of chronic graft vs host disease (cGVHD) (p < .001) were independent risk factors for CNS relapse after allo-HSCT. In conclusion, CNS relapse was a significant complication after allo-HSCT in ALL and was associated with poor prognosis. The incidences and outcomes were comparable between HID-HSCT and ISD-HSCT.

Comparison of different cytomegalovirus diseases following haploidentical hematopoietic stem cell transplantation.

Cytomegalovirus (CMV) can cause end-organ diseases including pneumonia, gastroenteritis, retinitis, and encephalitis in hematopoietic stem cell transplantation recipients. Potential differences among different CMV diseases remain uncertain. This study aimed to compare the clinical characteristics, risk factors, and mortality among different CMV diseases. A retrospective nested case-control study was performed based on a cohort of 3862 patients who underwent haploidentical hematopoietic stem cell transplantation at a single-center. CMV diseases occurred in 113 (2.92%) of 3862 haplo-HSCT recipients, including probable CMV pneumonia (CMVP, n = 34), proven CMV gastroenteritis (CMVG, n = 34), CMV retinitis (CMVR, n = 31), probable CMV encephalitis (CMVE, n = 7), and disseminated CMV disease (Di-CMVD, n = 7). Most (91.2%) cases of CMVG developed within 100 days, while most (90.3%) cases of CMVR were late onset. Refractory CMV infection and CMV viral load at different levels were associated with an increased risk of CMVP, CMVG, and CMVR. Compared with patients without CMV diseases, significantly higher non-relapse mortality at 1 year after transplantation was observed in patients with CMVP and CMVR, rather than CMVG. Patients with CMVP, Di-CMVD, and CMVE had higher overall mortality after diagnosis than that of patients with CMVG and CMVR (61.7%, 57.1%, 40.0% vs 27.7%, 18.6%, P = 0.001). In conclusion, the onset time, viral dynamics, and mortality differ among different CMV diseases. The mortality of CMV diseases remains high, especially for CMVP, Di-CMVD, and CMVE.

Incidence, Risk Factors, and Outcome of Immune-Mediated Neuropathies (IMNs) following Haploidentical Hematopoietic Stem Cell Transplantation.

Immune-mediated neuropathies (IMNs) following hematopoietic stem cell transplantation have been described recently, which, excluding Guillain-Barré syndrome and chronic inflammatory demyelinating polyneuropathy, may present with atypical patterns. This retrospective, nested, case-control study reviewed data from 3858 patients who received haploidentical hematopoietic stem cell transplantation (haplo-HSCT) during the past 10 years at a single center, and 40 patients (1.04%) with IMN following haplo-HSCT were identified. Chronic graft-versus-host disease (cGVHD) (P = .043) and cytomegalovirus (CMV) viremia (P = .035) were recognized as independent risk factors for the development of IMN after haplo-HSCT. There were no significant differences in overall survival (P = .619), disease-free survival (P = .609), nonrelapse mortality (P = .87), or the incidence of relapse (P = .583) between patients with and without IMN after haplo-HSCT. However, patients with post-transplant IMN were at higher risk of developing cGVHD (P = .012) than patients who did not develop IMN. Twenty-four of the 40 patients with IMN (60%) attained neurologic improvement after treatments including vitamins B1 and B12 and/or immunomodulatory agents. However, 19 (47.5%) patients still had persistent motor/sensory deficits despite receiving timely treatment. More studies are needed to help develop standardized diagnostic and therapeutic strategies for patients with post-transplant IMN.

A novel recombinant human thrombopoietin for treating prolonged isolated thrombocytopenia after allogeneic stem cell transplantation.

Patients with prolonged isolated thrombocytopenia (PT) after allogeneic stem cell transplantation (allo-SCT) are known to have a poor prognosis. However, there is no standard treatment for PT. The present study aimed to investigate the potential effect of a novel recombinant human thrombopoietin (rhTPO) in a cohort of patients with PT following allo-SCT. A total of 24 patients with PT (including delayed platelet engraftment and secondary failure of platelet recovery) were treated with rhTPO from July 1, 2016 to May 31, 2017. rhTPO injections were administered at 300 IU/kg/d for 28 consecutive days or until platelet counts were ≥ 50 × 109/L, independent of platelet transfusion. Response was defined as platelet recovery to ≥ 20 × 109/L for seven consecutive days without transfusion support during or within 7 days of the end of rhTPO treatment. All patients completed the 28 days of treatment, and none were withdrawn due to adverse effects. The overall response was 45.8%, which was significantly higher than historical data (12.2%, p < 0.001). The median response time was 12 (7-25) days from the initiation of rhTPO treatment. A response to rhTPO was associated with megakaryocytes in the bone marrow (positive vs. negative, 81.8 vs. 22.2%; p = 0.022). Among 11 patients exhibiting a response to rhTPO, the median number of megakaryocytes in bone marrow was increased significantly (10 vs. 2; p = 0.036) after rhTPO treatment. In conclusion, the results of this preliminary study suggest that rhTPO may represent a therapeutic option, with a response of 45.8% for patients with PT after allo-SCT, and especially for those with megakaryocytes in the bone marrow. However, this should be further confirmed in randomized prospective clinical trials.

Incidence, Risk Factors, Microbiology and Outcomes of Pre-engraftment Bloodstream Infection After Haploidentical Hematopoietic Stem Cell Transplantation and Comparison With HLA-identical Sibling Transplantation.

Background: Bloodstream infection (BSI) is a common and serious complication after hematopoietic stem cell transplantation (HSCT). An investigation of the characteristics of pre-engraftment BSI after haploidentical HSCT compared with human leukocyte antigen (HLA)-identical sibling HSCT has not been conducted. Methods: A single-center cohort representing 1847 consecutive patients undergoing haploidentical or HLA-identical sibling HSCT from 2013 to 2016 was selected. We investigated the characteristics of pre-engraftment BSI after haploidentical HSCT and its impact on patient outcome, and we compared it with HLA-identical sibling HSCT. Results: After haploidentical HSCT, the cumulative incidence of pre-engraftment BSI was higher (30-day: 9.2% [7.6, 10.8] vs 1.7% [0.5, 2.9], P < .0001) and median onset of BSI was earlier (day +3 vs day +9, P = .001) than HLA-identical sibling HSCT. Escherichia coli, Klebsiella pneumoniae, and coagulase-negative staphylococci were the most common isolates after haploidentical HSCT. However, Enterococcus faecium was the most common isolate after HLA-identical sibling HSCT. A multivariate analysis suggested that variables associated with BSI after haploidentical HSCT included a diagnosis of myelodysplastic syndrome (MDS), an interval from diagnosis to HSCT ≥190 days, carbapenem therapy, and grade 3-4 intestinal mucositis. The same variables, except MDS, were also associated with BSI after HLA-identical sibling HSCT. The multivariate analysis also suggested that BSI was a risk factor for increased all-cause mortality at 3 months after haploidentical HSCT (hazard ratio = 2.281; 95% confidence interval: 1.334, 3.900; P = .003). Conclusions: Pre-engraftment BSI was more common after haploidentical HSCT than HLA-identical sibling HSCT. It was an independent factor associated with increased all-cause mortality at 3 months after haploidentical HSCT.

Mesenchymal stem cell deficiency influences megakaryocytopoiesis through the TNFAIP3/NF-κB/SMAD pathway in patients with immune thrombocytopenia.

Immune thrombocytopenia (ITP) is an autoimmune disease. Mesenchymal stem cells (MSCs) play important roles in the physiology and homeostasis of the haematopoietic system, including supporting megakaryocytic differentiation from CD34+ haematopoietic progenitor cells. Tumour necrosis factor alpha-induced protein 3 (TNFAIP3, also termed A20) plays a key role in terminating NF-κB signalling. Human genetic studies showed that the polymorphisms of the TNFAIP3 gene may contribute to ITP susceptibility. In this study, we showed a significant decrease in TNFAIP3 and increase in NF-κB/SMAD7 in ITP-MSCs. In co-cultures with CD34+ cells, NF-κB was overexpressed in MSCs from healthy controls (HC-MSCs) after transfection with NFKBIA (IκB)-specific short hairpin (sh)RNAs, resulting in MSC deficiency and a reduction in megakaryocytic differentiation and thrombopoiesis. Knockdown of TNFAIP3 expression using TNFAIP3-specific shRNAs in HC-MSCs affected megakaryocytopoiesis. However, IKBKB knockdown corrected megakaryocytopoiesis inhibition in the ITP-MSCs by decreasing NF-κB expression. Amplified TNFAIP3 expression in ITP-MSCs by TNFAIP3 cDNA can facilitate megakaryocyte differentiation. shRNA-mediated knockdown of SMAD7 expression rescued the impaired MSC function in ITP patients. Therefore, we demonstrate that a pathological reduction in TNFAIP3 levels induced NF-κB/SMAD7 pathway activation, causing a deficiency in MSCs in ITP patients. The ability of ITP-MSCs to support megakaryocytic differentiation and thrombopoiesis of CD34+ cells was impaired.

IgG synthesis rate and anti-myelin oligodendrocyte glycoprotein antibody in CSF may be associated with the onset of CNS demyelination after haplo-HSCT.

Haploidentical hematopoietic stem cell transplant (haplo-HSCT) is an upfront and effective therapy for hematology patients, but it usually has many complications, such as neurological complications. As one of the neurological complications following haplo-HSCT, immune-mediated demyelinating diseases of the central nervous system (CNS) seriously affect a patient's quality of life. However, the incidence, risk factors, and pathogenesis of CNS demyelination are not very well understood. Thirty of the 1526 patients (1.96%) suffered from CNS demyelination. In univariate analysis, we found that blood-brain barrier (BBB) permeability and the CSF IgG synthesis index (IgG-Syn) were related to the occurrence of CNS demyelination (p < 0.05). In a multivariate analysis, the IgG-Syn (OR = 1.017, 95% CI 1.003-1.031, p = 0.019) and CSF anti-myelin oligodendrocyte glycoprotein antibody (MOG.Ab) (OR = 12.059, 95% CI 1.141-127.458, p = 0.038) were independently associated with the onset of CNS demyelination. We also studied the possible pathogenesis of CNS demyelination. Immune reconstitution (the cell proportions of CD19+ B cells, CD3+ T cells, and CD4+ T cells); the counts of leucocytes, lymphocytes, monocytes, and platelets; and the levels of immunoglobulins A, G, and M 30, 60, and 90 days after HSCT showed no significant differences between CNS demyelination and no demyelination (p > 0.05). The probabilities of overall survival showed no significant differences between patients with and without demyelination (p > 0.05). Only four deaths in 30 patients, but bringing projected survival to less than 20%.We imply that IgG-Syn and CSF MOG. Ab may be associated with the onset of CNS demyelination during 2 weeks of neurological symptoms in patients with brain or spinal cord MRI abnormality. Immune reconstitution may not be the pathogenesis of CNS demyelination.