HLA-C dysregulation as a possible mechanism of immune evasion in SARS-CoV-2 and other RNA-virus infections

One of the mechanisms by which viruses can evade the host's immune system is to modify the host's DNA methylation pattern. This work aims to investigate the DNA methylation and gene expression profile of COVID-19 patients, divided into symptomatic and asymptomatic, and healthy controls, focusing on genes involved in the immune response. In this study, changes in the methylome of COVID-19 patients' upper airways cells, the first barrier against respiratory infections and the first cells presenting viral antigens, are shown for the first time. Our results showed alterations in the methylation pattern of genes encoding proteins implicated in the response against pathogens, in particular the HLA-C gene, also important for the T-cell mediated memory response. HLA-C expression significantly decreases in COVID-19 patients, especially in those with a more severe prognosis and without other possibly confounding co-morbidities. Moreover, our bionformatic analysis revealed that the identified methylation alteration overlaps with enhancers regulating HLA-C expression, suggesting an additional mechanism exploited by SARS-CoV-2 to inhibit this fundamental player in the host's immune response. HLA-C could therefore represent both a prognostic marker and an excellent therapeutic target, also suggesting a preventive intervention that conjugate a virus-specific antigenic stimulation with an adjuvant increasing the T-cell mediated memory response

Synthesis of SARS-CoV-2 Mpro inhibitors bearing a cinnamic ester warhead with in vitro activity against human coronaviruses

COVID-19 now ranks among the most devastating global pandemics in history. The causative virus, SARS-CoV-2, is a new human coronavirus (hCoV) that spreads among humans and animals. Great efforts have been made to develop therapeutic agents to treat COVID-19, and among the available viral molecular targets, the cysteine protease SARS-CoV-2 Mpro is considered the most appealing one due to its essential role in viral replication. However, the inhibition of Mpro activity is an interesting challenge and several small molecules and peptidomimetics have been synthesized for this purpose. In this work, the Michael acceptor cinnamic ester was employed as an electrophilic warhead for the covalent inhibition of Mpro by endowing some peptidomimetic derivatives with such a functionality. Among the synthesized compounds, the indole-based inhibitors 17 and 18 efficiently impaired the in vitro replication of beta hCoV-OC-43 in the low micromolar range (EC50 = 9.14 μM and 10.1 μM, respectively). Moreover, the carbamate derivative 12 showed an antiviral activity of note (EC50 = 5.27 μM) against another hCoV, namely hCoV-229E, thus suggesting the potential applicability of such cinnamic pseudopeptides also against human alpha CoVs. Taken together, these results support the feasibility of considering the cinnamic framework for the development of new Mpro inhibitors endowed with antiviral activity against human coronaviruses

A validated cellular biobank for β-thalassemia

Background: Cellular biobanking is a key resource for collaborative networks planning to use same cells in studies aimed at solving a variety of biological and biomedical issues. This approach is of great importance in studies on β-thalassemia, since the recruitment of patients and collection of specimens can represent a crucial and often limiting factor in the experimental planning. Methods: Erythroid precursor cells were obtained from 72 patients, mostly β-thalassemic, expanded and cryopreserved. Expression of globin genes was analyzed by real time RT-qPCR. Hemoglobin production was studied by HPLC. Results: In this paper we describe the production and validation of a Thal-Biobank constituted by expanded erythroid precursor cells from β-thalassemia patients. The biobanked samples were validated for maintenance of their phenotype after (a) cell isolation from same patients during independent phlebotomies, (b) freezing step in different biobanked cryovials, (c) thawing step and analysis at different time points. Reproducibility was confirmed by shipping the frozen biobanked cells to different laboratories, where the cells were thawed, cultured and analyzed using the same standardized procedures. The biobanked cells were stratified on the basis of their baseline level of fetal hemoglobin production and exposed to fetal hemoglobin inducers. Conclusion: The use of biobanked cells allows stratification of the patients with respect to fetal hemoglobin production and can be used for determining the response to the fetal hemoglobin inducer hydroxyurea and to gene therapy protocols with reproducible results

現地観測に基づく河川流の乱流特性に関する研究

博士（工学）神戸大

Rituximab Monotherapy or in Combination with Bendamustine Is Not Inferior to Rituximab-CHOP Regimen in the Treatment of Patients with Splenic Marginal Zone Lymphoma in the Real Life

Splenic marginal zone lymphoma (SMZL) is a rare lymphoma belonging to the marginal zone lymphoproliferative disorders. Usually, SMZL occurs with indolent presentation and, when required, the standard of care is represented by rituximab-based regimens. No direct comparison of different rituximab-based combinations and polychemotherapy regimens has been conducted to date. In a monocentric cohort of 68 SMLZ patients, we showed that rituximab in monotherapy or in combination with bendamustine, compared with rituximab associated with the polychemotherapy cycle cyclophosphamide, hydroxydaunorubicin, vincristine and prednisolone (CHOP), resulted in a higher 5-year progression-free survival (91.3 ± 9% and 75 ± 15.7% vs. 30.8 ± 12.1%, p < 0.001). Platelets at diagnosis <100 ×109/L (p = 0.034, HR = 4.3) and transformation into diffuse large B-cell lymphoma (p = 0.031, HR = 4.3) were associated with a lower overall survival

Point-of-Care and Rapid Tests for the Etiological Diagnosis of Respiratory Tract Infections in Children: A Systematic Review and Meta-Analysis

Fever is one of the most common causes of medical evaluation of children, and early discrimination between viral and bacterial infection is essential to reduce inappropriate prescriptions. This study aims to systematically review the effects of point-of-care tests (POCTs) and rapid tests for respiratory tract infections on changing antibiotic prescription rate, length of stay, duration of therapy, and healthcare costs. Embase, MEDLINE, and Cochrane Library databases were systematically searched. All randomized control trials and non-randomized observational studies meeting inclusion criteria were evaluated using the NIH assessment tool. A meta-analysis was performed to assess the effects of rapid influenza diagnostic tests and film-array respiratory panel implementation on selected outcomes. From a total of 6440 studies, 57 were eligible for the review. The analysis was stratified by setting and POCT/rapid test type. The most frequent POCTs or rapid tests implemented were the Rapid Influenza Diagnostic Test and film-array and for those types of test a separate meta-analysis assessed a significant reduction in antibiotic prescription and an improvement in oseltamivir prescription. Implementing POCTs and rapid tests to discriminate between viral and bacterial infections for respiratory pathogens is valuable for improving appropriate antimicrobial prescriptions. However, more studies are needed to assess these findings in pediatric settings

Vaccination and Antiviral Treatment Reduce the Time to Negative SARS-CoV-2 Swab: A Real-Life Study

Clinical trials demonstrated the role of vaccines and antiviral treatments against SARS-CoV-2 in reducing the likelihood of disease progression and death. However, there are limited data available regarding the time to negativity of people who received these treatments. Further, several comorbidities and risk factors might affect the impact of vaccines and antiviral treatments. To this end, we aimed to evaluate and disentangle the impact of anti-SARS-CoV-2 treatments and that of underlying clinical factors associated with a shortened length of SARS-CoV-2 infection. Hence, we recorded the timeframe of positive nasopharyngeal swab in people infected while being hospitalized for reasons other than SARS-CoV-2 infection. All patients who died or were discharged with a positive swab were excluded from the study. A total of 175 patients were included in this study. Clinical conditions encompass malignancies, immunological disorders, cardiovascular, metabolic, neurodegenerative, and chronic kidney disease. Most of the participants (91.4%) were vaccinated before admission to the hospital, and 65.1% received antiviral treatment within three days after the symptom’s onset. Unvaccinated patients had a longer median time to negativity than people who received at least two doses of vaccine (18 vs. 10 days). Concerning the clinical conditions of all patients, multivariate analysis highlighted a lower probability of 14-day conversion of antigenic test positivity in patients with hematological malignancy, including those vaccinated and those exposed to antiviral therapies. In conclusion, our data showed that prompt administration of antiviral treatments accelerates the clearance of SARS-CoV-2. Further, in the elderly patients under study, previous vaccination and antiviral treatment synergize to reduce time to negativity. This translates into a shorter hospitalization time and a lower risk of transmission through patients and connected healthcare workers in a hospital ward setting, with considerable improvement in cost-effective care management

Targeted genome editing in human repopulating haematopoietic stem cells

Targeted genome editing by artificial nucleases has brought the goal of site-specific transgene integration and gene correction within the reach of gene therapy. However, its application to long-term repopulating haematopoietic stem cells (HSCs) has remained elusive. Here we show that poor permissiveness to gene transfer and limited proficiency of the homology-directed DNA repair pathway constrain gene targeting in human HSCs. By tailoring delivery platforms and culture conditions we overcame these barriers and provide stringent evidence of targeted integration in human HSCs by long-term multilineage repopulation of transplanted mice. We demonstrate the therapeutic potential of our strategy by targeting a corrective complementary DNA into the IL2RG gene of HSCs from healthy donors and a subject with X-linked severe combined immunodeficiency (SCID-X1). Gene-edited HSCs sustained normal haematopoiesis and gave rise to functional lymphoid cells that possess a selective growth advantage over those carrying disruptive IL2RG mutations. These results open up new avenues for treating SCID-X1 and other diseases

Genetic engineering of hematopoiesis for targeted IFN-α delivery inhibits breast cancer progression

The immunosuppressive tumor microenvironment represents a major hurdle to cancer therapy. We developed a gene transfer strategy into hematopoietic stem cells (HSCs) to target transgene expression to tumor-infiltrating monocytes/macrophages. Using a combination of transcriptional and microRNA-mediated control, we achieved selective expression of an interferon-α (IFN-α) transgene in differentiated monocytes of human hematochimeric mice. We show that IFN-α transgene expression does not impair engraftment and long-term multilineage repopulation of NSG (NOD/LtSz-scidIL2Rγ) mice by transplanted human HSCs. By providing a source of human cytokines in the mice, we improved the functional reconstitution of human myeloid, natural killer, and T cell lineages, and achieved enhanced immune-mediated clearance of transplanted human breast tumors when hematopoiesis was engineered for tumor-targeted IFN-α expression. By applying our strategy to mouse breast cancer models, we achieved inhibition of tumor progression and experimental metastases in an autologous setting, likely through enhanced generation of effector T cells and their recruitment to the neoplastic tissues. By forcing IFN-α expression in tumor-infiltrating macrophages, we blunted their innate protumoral activity and reprogrammed the tumor microenvironment toward more effective dendritic cell activation and immune effector cell cytotoxicity. Overall, our studies validate the feasibility, safety, and therapeutic potential of a new cancer gene therapy strategy, and open the way to test this approach as adjuvant therapy in advanced breast cancer patients