A Traceable Vaccine Supply Management System.

Everyone should be vaccinated, but the eligibility and safety of the vaccine are always overlooked by most people. The outbreak of COVID-19 has led many countries to intensify the development and production of the COVID-19 vaccine. and some countries have even required universal vaccination against this epidemic. However, such popularization of vaccination has also exposed various flaws in vaccine management that existed in the past, and vaccinators have become more concerned about the effectiveness of their vaccinations. In this paper, we propose a blockchain-based traceable vaccine management system. First, the system uses smart contracts to store the records generated during the whole process, from vaccine production to vaccination. Second, the proposed scheme uses the Edwards-curve digital signature algorithm (EdDSA) to guarantee the security and integrity of these data. Third, the system participants can access the corresponding data according to their authority to ensure the transparency of the whole system operation process. Finally, this paper will also conduct a security analysis of the whole system to ensure that the system can resist potential attacks by criminals.

Incentive EMR Sharing System Based on Consortium Blockchain and IPFS.

Electronic medical records (EMRs) are extremely private data in the medical industry. Clinicians use the patient data that the EMR stores to quickly assess a patient's status and save diagnostic information. In the conventional medical model, it is easy for duplicate exams, medical resource waste, or the loss of medical records to happen when a patient is transferred between several medical facilities due to problems with data sharing and exchange, inadequate data privacy, security, confidentiality, and difficulties with data traceability. This paper recommends a Hyperledger Fabric-based strategy to promote the exchange of EMR models. With the use of Hyperledger Fabric, EMR stakeholders can be brought into the channel to facilitate data sharing. Attribute-based access control (ABAC) allows users to design the data access control policy, and the data access control may improve security. Any record stored in the blockchain can be viewed using the Hyperledger Fabric feature and it cannot be altered or destroyed, ensuring data traceability. Through proxy re-encryption, which makes sure that the data is not leaked during data exchange, data secrecy can be ensured. A module for medical tokens has now been added. Many foreign medical institutions currently use the medical token system, and the system described in this paper can use the tokens to pay for some medical expenses. The tokens are obtained by the patient's initiative to share their EMR with the medical institution for research, which is how many foreign medical institutions currently use the medical token mechanism. This paradigm can encourage the growth of medical data by enabling stakeholders to collaborate and share EMR trust.

WPSS is a strong prognostic indicator for clinical outcome of allogeneic transplant for myelodysplastic syndrome in Southeast Asian patients.

To better understand the predictive factors and improve clinical outcome of allogeneic transplant for patients with myelodysplastic syndrome (MDS), we retrospectively analyzed the post-transplant outcome of 60 Southeast Asian patients with MDS. Multivariate analysis showed that WHO classification-based Prognostic Scoring System (WPSS) significantly affect overall survival (OS), progression-free survival (PFS), cumulative incidence of relapse (CIR), and cumulative incidence of non-relapse mortality (CINRM). Stratified by WPSS into very low/low, intermediate, high, and very high-risk categories, 3-year OS was 100, 61, 37, and 18% (p = 0.02); PFS was 100, 55, 32, and 18% (p = 0.014); CIR was 12, 24, 38, and 59% (p = 0.024); CINRM was 0, 6, 12, and 26% (p = 0.037), respectively. WHO classification, Revised International Prognostic Scoring System (IPSS-R), IPSS-R-defined cytogenetic risk groups, donor gender, and acute and chronic graft vs host disease (GVHD) also influenced different aspects of transplant outcome. We found that WPSS is a powerful predictor of post-transplant outcome. WPSS provides an important model not only for prognostication but also for exploration of further post-transplant measures such as immunological maneuvers or novel therapy to improve the poor outcome of high-risk patients.

Pre-transplant achievement of negativity in minimal residual disease and French-American-British L1 morphology predict superior outcome after allogeneic transplant for Philadelphia chromosome positive acute lymphoblastic leukemia: an analysis of Southeast Asian patients.

To better understand predictive factors and improve the clinical outcome of allogeneic transplant for patients with Philadelphia positive acute lymphoblastic leukemia, we analyzed 67 Southeast Asian patients transplanted in our institutions. Multivariate analysis showed that disease status before transplant, year of transplant and, interestingly, French-American-British (FAB) subtype had a significant impact on overall survival (OS) and non-relapse mortality. Patients who were minimal residual disease (MRD) negative at transplant had a 3-year OS of 73% compared to those who were MRD positive (45%) and refractory (0%). The 3-year cumulative incidence of relapse was 18% and 36% for the MRD negative and positive groups, respectively. FAB L1 subtype had a significantly superior 3-year OS of 63% vs. 29% for L2 subtype. Pre-transplant use of a tyrosine kinase inhibitor significantly improved outcomes in univariate but not multivariate analysis, as it served to induce more patients into MRD negativity, which was the factor that directly improved transplant outcome.

Long-term outcomes of alemtuzumab-based reduced-intensity conditioned hematopoietic stem cell transplantation for myelodysplastic syndrome and acute myelogenous leukemia secondary to myelodysplastic syndrome.

Allogeneic hematopoietic stem cell transplantation (HSCT) with reduced-intensity conditioning (RIC) offers a potential cure for patients with myelodysplastic syndrome (MDS) who are ineligible for standard-intensity regimens. Previously published data from our institution suggest excellent outcomes at 1 yr using a uniform fludarabine, busulfan, and alemtuzumab-based regimen. Here we report long-term follow-up of 192 patients with MDS and acute myelogenous leukemia (AML) secondary to MDS (MDS-AML) transplanted with this protocol, using sibling (n = 45) or matched unrelated (n = 147) donors. The median age of the cohort was 57 yr (range, 21 to 72 yr), and median follow-up was 4.5 yr (range, 0.1 to 10.6 yr). The 5-yr overall survival (OS), event-free survival, and nonrelapse mortality were 44%, 33%, and 26% respectively. The incidence of de novo chronic graft-versus-host disease (GVHD) was low at 19%, illustrating the efficacy of alemtuzumab for GVHD prophylaxis. Conversely, the 5-yr relapse rate was 51%. For younger patients (age <50 yr), the 5-yr OS and relapse rates were 58% and 39%, respectively. On multivariate analysis, advanced age predicted significantly worse outcomes, with patients age >60 yr having a 5-yr OS of 15% and relapse rate of 66%. Patients receiving preemptive donor lymphocyte infusions had an impressive 5-yr OS of 67%, suggesting that this protocol may lend itself to the incorporation of immunotherapeutic strategies. Overall, these data demonstrate good 5-yr OS for patients with MDS and MDS-AML undergoing alemtuzumab-based RIC-HSCT. The low rate of chronic GVHD is encouraging, and comparative studies with other RIC protocols are warranted.

Hepatitis B virus infection: pathogenesis, reactivation and management in hematopoietic stem cell transplant recipients.

Hepatitis B virus (HBV) is a partially double stranded DNA virus that can integrate into host cell chromosomes as covalently closed circular DNA forms. HBV reactivation following hematopoietic stem cell transplantation in recipients with evidence of past HBV exposure, as well as exacerbation of a current HBV infection in HBV carrier recipients, secondary to chemotherapy and post-transplant immunosuppression that affect both humoral and cell-mediated control of HBV infection, are well documented in the literature. Management options include HBV-DNA screening and antiviral prophylaxis. Nucleos(t)ide analogues have been used at the start of chemotherapy and pretransplantation, with the course continuing for 6 months. However, depending on the serum HBV-DNA level, the antiviral agent might be given until a therapeutic end point is reached.

Alemtuzumab-based reduced-intensity conditioning allogeneic transplantation for myeloma and plasma cell leukemia - a single-institution experience.

BACKGROUND: Reduced-intensity conditioning allogeneic transplantation for myeloma is associated with lower non-relapse mortality and higher relapse rates in comparison with myeloablative conditioning transplants. PATIENTS AND METHODS: We have retrospectively audited 19 patients with myeloma or primary plasma cell leukemia who received allogeneic transplantation with a uniform alemtuzumab-based reduced-intensity conditioning protocol. These patients had not been treated with bortezomib or lenalidomide before transplantation. RESULTS: The treatment-related mortality at 1 year was (4/19) 21% with low incidence of graft-versus-host disease (6%) and 2-year progression-free survival and overall survival rates of 35% and 42%, respectively. CONCLUSION: Progression-free survival in this cohort of patients is comparable to previously published data of reduced-intensity conditioning allogeneic transplantation in myeloma. However, there is no plateau observed on the survival curves with a significant transplant-related mortality of 21%. Therefore, alemtuzumab-based allogeneic transplantation cannot be recommended as standard practice outside of clinical trials for treatment of myeloma.

Alemtuzumab with fludarabine and cyclophosphamide reduces chronic graft-versus-host disease after allogeneic stem cell transplantation for acquired aplastic anemia.

We evaluated a novel alemtuzumab-based conditioning regimen in HSCT for acquired severe aplastic anemia (SAA). In a multicenter retrospective study, 50 patients received transplants from matched sibling donors (MSD; n = 21) and unrelated donors (UD; n = 29), using fludarabine 30 mg/m² for 4 days, cyclophosphamide 300 mg/m² for 4 days, and alemtuzumab median total dose of 60 mg (range:40-100 mg). Median age was 35 years (range 8-62). Overall survival at 2 years was 95% ± 5% for MSD and 83% for UD HSCT (p 0.34). Cumulative incidence of graft failure was 9.5% for MSD and 14.5% for UD HSCT. Full-donor chimerism (FDC) in unfractionated peripheral blood was 42%; no patient achieved CD3 FDC. Acute GVHD was observed in only 13.5% patients (all grade I-II) and only 2 patients (4%) developed chronic GVHD. A low incidence of viral infections was seen. Factors influencing overall survival were HSCT comorbidity 2-year index (92% with score 0-1 vs 42% with score ≥ 2, P < .001) and age (92% for age < 50 years vs 71% ≥ 50 years, P < .001). Our data suggest that the use of an alemtuzumab-based HSCT regimen for SAA results in durable engraftment with a low incidence of chronic GVHD.

Outcome of Chinese children with unrelated donor hematopoietic stem cell transplantation.

BACKGROUND: To evaluate the prognostic factors and outcomes in Chinese children undergoing unrelated donor hematopoietic stem cell transplantation (UDT). METHODS: Retrospective analysis of clinical data from 53 consecutive children who received UDT from November 2002 to December 2007 in our center. RESULTS: The median recipient age was 8.4 years (range 1.5-21). With a median follow-up of 36 months (range 18-80), the probability of 3-year overall survival (OS) was 71.5%. Treatment-related mortality (TRM) was 19.0%, and 9.5% died after post-transplant leukemia relapse. Incidence of grades I-II, III-IV acute and chronic graft versus host disease (GVHD) was 63%, 29%, and 46%. There was significant difference in OS between patients older or younger than 10 years (50.0% vs. 84.8%, P = 0.003), patients with different underlying diseases (ALL, AML, CML, and non-malignant disease: 36.4%, 80.0%, 61.5%, and 100%, P = 0.001) and patients receiving either HLA 0-1 versus 2-3 loci high-resolution mismatched UDT (83.3% vs. 53.3%, P = 0.034). The OS was not affected by the stem cell source (peripheral stem cell 70.3%, bone marrow 87.5% vs. cord blood 62.5%, P = 0.542) or the severity of acute GVHD (grade 0-II 77.8% vs. grade III-IV 60.0%, P = 0.140). CONCLUSIONS: The important prognostic factors for OS after UDT were the degree of HLA match, the age of patient and the type of underlying disease. Patients < 10-year with non-malignant disease receiving 0-1 locus high-resolution mismatched UDT had the most favorable outcomes.

Next-generation sequencing of the TET2 gene in 355 MDS and CMML patients reveals low-abundance mutant clones with early origins, but indicates no definite prognostic value.

Mutations in the TET2 gene are frequent in myeloid disease, although their biologic and prognostic significance remains unclear. We analyzed 355 patients with myelodysplastic syndromes using "next-generation" sequencing for TET2 aberrations, 91 of whom were also subjected to single-nucleotide polymorphism 6.0 array karyotyping. Seventy-one TET2 mutations, with a relative mutation abundance (RMA) ≥ 10%, were identified in 39 of 320 (12%) myelodysplastic syndrome and 16 of 35 (46%) chronic myelomonocytic leukemia patients (P < .001). Interestingly, 4 patients had multiple mutations likely to exist as independent clones or on alternate alleles, suggestive of clonal evolution. "Deeper" sequencing of 96 patient samples identified 4 additional mutations (RMA, 3%-6.3%). Importantly, TET2 mutant clones were also found in T cells, in addition to CD34(+) and total bone marrow cells (23.5%, 38.5%, and 43% RMA, respectively). Only 20% of the TET2-mutated patients showed loss of heterozygosity at the TET2 locus. There was no difference in the frequency of genome-wide aberrations, TET2 expression, or the JAK2V617F 46/1 haplotype between TET2-mutated and nonmutated patients. There was no significant prognostic association between TET2 mutations and World Health Organization subtypes, International Prognostic Scoring System score, cytogenetic status, or transformation to acute myeloid leukemia. On multivariate analysis, age (> 50 years) was associated with a higher incidence of TET2 mutation (P = .02).

Rapid recovery of lymphocyte subsets is not associated with protection from relapse of myelodysplastic syndromes and acute myeloid leukaemia after haematopoietic stem cell transplantation using a reduced intensity conditioning regimen and alemtuzumab.

Graft-versus-leukaemia (GvL) and graft-versus-host disease (GvHD) are both caused by alloreactive lymphocytes. We previously reported that GvHD correlated with higher numbers of effector CD4 T cells and Natural Killer cells early after allogeneic transplantation using a regimen comprising fludarabine, busulphan and alemtuzumab. Here, we assessed immune cell subset recovery in these patients in the context of early myeloid malignant disease relapse. Despite the close relationship between the GvL and GvHD immune responses, rapid recovery of lymphocyte subsets was not associated with protection from disease relapse. These results indicated that GvL may be weak in this treatment setting for patients with myelodysplastic syndromes and acute myeloid leukaemia. Consistent with low GvL activity, we previously reported that mixed T cell chimaerism had no detrimental effect on relapse in this treatment setting and instead correlated with better outcome because of reduced GvHD incidence. We now report that patients with significantly higher lymphocyte numbers prior to transplantation subsequently maintained the mixed T cell chimaeric state. This pre-transplant profile, together with absence of the early post-transplant signature indicative of GvHD predisposition, could potentially be used to identify patients suitable for early withdrawal of immunosuppression and prophylactic donor leucocyte infusion to boost GvL activity.

Allogeneic hematopoietic stem-cell transplantation for patients 50 years or older with myelodysplastic syndromes or secondary acute myeloid leukemia.

PURPOSE: This study was performed to examine the characteristics of transplant activity for patients with myelodysplastic syndromes (MDS) older than 50 years within the European Group for Blood and Marrow Transplantation, and to evaluate the factors predicting outcome within this group of patients. PATIENTS AND METHODS: We performed a retrospective multicenter analysis of 1,333 MDS patients age 50 years or older who received transplantation within the EBMT since 1998. The median recipient age was 56 years, with 884 patients (66%) age 50 to 60 years and 449 (34%) patients older than 60 years. There were 811 HLA-matched sibling (61%) and 522 (39%) unrelated donor transplants. Five hundred patients (38%) received standard myeloablative conditioning (SMC), and 833 (62%) received reduced intensity conditioning (RIC). RESULTS: The 4-year estimate for overall survival of the whole cohort was 31%. On multivariate analysis, use of RIC (hazard ratio [HR], 1.44; 95% CI, 1.13 to 1.84; P < .01) and advanced disease stage at transplantation (HR, 1.51; 95% CI, 1.18 to 1.93; P < .01) were associated with an increased relapse rate. In contrast, advanced disease stage at transplantation (HR, 1.43; 95% CI, 1.13 to 1.79; P = .01), use of an unrelated donor (P = .03), and RIC (HR, 0.79; 95% CI, 0.65 to 0.97; P = .03) were independent variables associated with nonrelapse mortality. Advanced disease stage at transplantation (HR, 1.55; 95% CI, 1.32 to 1.83; P < .01) was the major independent variable associated with an inferior 4-year overall survival. CONCLUSION: Allogeneic hematopoietic stem-cell transplantation remains a potential curative therapeutic option for many older patients with MDS. In this analysis, disease stage at time of transplantation, but not recipient age or the intensity of the conditioning regimens, was the most important factor influencing outcomes.

Imbalance of effector and regulatory CD4 T cells is associated with graft-versus-host disease after hematopoietic stem cell transplantation using a reduced intensity conditioning regimen and alemtuzumab.

BACKGROUND: A variety of immune pathways can lead to graft-versus-host disease. A better understanding of the type of immune response causing graft-versus-host disease in defined clinical hematopoietic stem cell transplant settings is required to inform development of methods for monitoring patients and providing them tailored care. DESIGN AND METHODS: Twenty-five patients were recruited presenting with myeloid malignancies and treated with a reduced intensity conditioning transplant regimen with graft-versus-host disease prophylaxis comprising in vivo lymphocyte depletion with alemtuzumab and cyclosporin. A prospective study was performed of lymphocyte subset reconstitution in peripheral blood in relation to the incidence of graft-versus-host disease. RESULTS: Acute graft-versus-host disease was associated with significantly higher numbers of natural killer cells and donor-derived effector CD4 T cells (CD45RO(+) CD27(-)) early (day 30) after transplantation (p=0.04 and p=0.02, respectively). This association was evident before the emergence of clinical pathology in six out of seven patients. Although numbers of regulatory CD4 T cells (CD25(high) Foxp3(+)) were similar at day 30 in all patients, a significant deficit in those who developed acute graft-versus-host disease was apparent relative to effector CD4 T cells (median of 41 effectors per regulatory cell compared to 12 to 1 for patients without graft-versus-host disease) (p=0.03). By day 180, a functional regulatory CD4 T-cell population had expanded significantly in patients who developed chronic graft-versus-host disease, reversing the imbalance (median of 3 effectors per regulatory cell compared to 9.6 to 1 for patients without graft-versus-host disease) (p=0.018) suggesting no overt absence of immune regulation in the late onset form of the disease. CONCLUSIONS: Imbalance of effector and regulatory CD4 T cells is a signature of graft-versus-host disease in this transplantation protocol.

IL-17-producing CD4(+) T cells, pro-inflammatory cytokines and apoptosis are increased in low risk myelodysplastic syndrome.

Immunological responses are increasingly recognised as being important in the initiation and progression of myelodysplastic syndrome (MDS). Indeed, autoimmune diseases commonly occur in association with MDS, particularly in subtypes with a low risk of leukaemic transformation. This study showed for the first time that the numbers of CD3(+) CD4(+) IL-17 producing T cells (Th17) were markedly increased in low risk MDS compared with high risk MDS (P < 0.01). An inverse relationship between the numbers of Th17 cells and naturally occurring CD4(+)CD25(high) FoxP3(+) regulatory T cells (Tregs) were also described. The Th17:Tregs ratio was significantly higher in low risk disease (P < 0.005) compared with high risk MDS and was correlated with increased bone marrow (BM) apoptosis (P < 0.01). Tregs from MDS patients suppressed interferon-gamma (IFN-gamma) secretion by effector CD4(+) T cells but had no effect on interleukin (IL)-17 production. In addition, the serum levels of IL-7, IL-12, RANTES and IFN-gamma are significantly elevated in low risk MDS, while inhibitory factors, such as IL-10 and soluble IL-2 receptor, are significantly higher in high risk disease. The 'unfavourable' Th17:Tregs ratio in low risk MDS may explain the higher risk of autoimmunity and the improved response to immune suppression in patients with low risk MDS compared to those with high risk disease.

Acute myeloid leukaemia presenting with mediastinal myeloid sarcoma: report of three cases and review of literature.

Although myeloid sarcomas (MS) are frequently associated with acute myeloid leukaemia (AML), the occurrence of mediastinal MS is a much rarer event. The authors describe a distinct group of three AML patients with mediastinal MS and complex cytogenetics presenting at their centre over a 7-year period. Clinical features consistent with superior vena caval obstruction were noted at presentation in two of the three patients. Mediastinal mass was detected on routine chest radiography, and biopsies confirmed the diagnosis of MS. One patient relapsed after consolidation chemotherapy and died from progressive disease. Two patients underwent allogeneic haemopoietic stem cell transplant, but succumbed to transplant related complications. Review of mediastinal MS over the last 20 years shows that a significant proportion of patients have complex cytogenetic abnormalities and a poor long-term prognosis. Early and accurate diagnosis is essential and patients should be managed along the lines of high risk AML.

Toxoplasmosis following alemtuzumab based allogeneic haematopoietic stem cell transplantation.

Alemtuzumab is a humanised monoclonal antibody against CD52 used as an immunosuppressive agent in allogeneic HSCT. Regimens including alemtuzumab for allogeneic haematopoietic stem cell transplant (HSCT) conditioning have been associated with an increased incidence of viral complications. Patients with prior toxoplasma exposure undergoing alemtuzumab containing HSCT could therefore be expected to be at a higher risk of toxoplasma reactivation. We conducted a retrospective review of 220 alemtuzumab based allogeneic HSCT performed over a 4 year period, of which 202 were reduced intensity conditioning (RIC) HSCT. A total of 67 patients (30%) in whom the pre-transplant recipient toxoplasma IgG test was positive were classified as high-risk for toxoplasma infection. All patients started trimethoprim/sulfamethoxazole prophylaxis following HSCT when the neutrophil count was > or = 1x10(9)/l. Two high-risk patients developed toxoplasma invasive disease with cerebral involvement at 2 and 4 months post-transplantation respectively. The incidence of toxoplasma disease in the entire cohort and amongst high-risk patients was 0.9% and 3.0% respectively. Despite in vivo T-cell depletion with alemtuzumab, the incidence of toxoplasma disease in our cohort was comparable with previously reported T-cell replete HSCT studies.

Outcomes of patients with haematological malignancies admitted to intensive care unit. A comparative review of allogeneic haematopoietic stem cell transplantation data.

The outcomes of 55 consecutive haemato-oncology patients admitted to the intensive care unit (ICU) were retrospectively analysed. Twenty-eight patients were admitted following haemopoietic stem cell transplantation (HSCT). Thirty-nine patients were admitted with respiratory failure, and all patients required respiratory support. Seventeen patients survived to be discharged from ICU, with an actuarial 1-year survival of 18%. Overall survival between patients who received intensive chemotherapy and those who underwent allogeneic HSCT was not significantly different (19% vs. 10%, P = 0.19). None of the nine myeloablative HSCT recipients survived (median survival: 9 d). Six of the 15 reduced-intensity conditioned HSCT recipients survived beyond 1 year (median survival: 1050 d, range: 438-1437).