Molecular barcoding of viral vectors enables mapping and optimization of mRNA trans-splicing.

Genome editing has proven to be highly potent in the generation of functional gene knockouts in dividing cells. In the CNS however, efficient technologies to repair sequences are yet to materialize. Reprogramming on the mRNA level is an attractive alternative as it provides means to perform in situ editing of coding sequences without nuclease dependency. Furthermore, de novo sequences can be inserted without the requirement of homologous recombination. Such reprogramming would enable efficient editing in quiescent cells (e.g., neurons) with an attractive safety profile for translational therapies. In this study, we applied a novel molecular-barcoded screening assay to investigate RNA trans-splicing in mammalian neurons. Through three alternative screening systems in cell culture and in vivo, we demonstrate that factors determining trans-splicing are reproducible regardless of the screening system. With this screening, we have located the most permissive trans-splicing sequences targeting an intron in the Synapsin I gene. Using viral vectors, we were able to splice full-length fluorophores into the mRNA while retaining very low off-target expression. Furthermore, this approach also showed evidence of functionality in the mouse striatum. However, in its current form, the trans-splicing events are stochastic and the overall activity lower than would be required for therapies targeting loss-of-function mutations. Nevertheless, the herein described barcode-based screening assay provides a unique possibility to screen and map large libraries in single animals or cell assays with very high precision.

Occurrence of SARS-CoV-2 viremia is associated with genetic variants of genes related to COVID-19 pathogenesis.

Introduction: SARS-CoV-2 viral load has been related to COVID-19 severity. The main aim of this study was to evaluate the relationship between SARS-CoV-2 viremia and SNPs in genes previously studied by our group as predictors of COVID-19 severity. Materials and methods: Retrospective observational study including 340 patients hospitalized for COVID-19 in the University Hospital La Princesa between March 2020 and December 2021, with at least one viremia determination. Positive viremia was considered when viral load was above the quantifiable threshold (20 copies/ml). A total of 38 SNPs were genotyped. To study their association with viremia a multivariate logistic regression was performed. Results: The mean age of the studied population was 64.5 years (SD 16.6), 60.9% patients were male and 79.4% white non-Hispanic. Only 126 patients (37.1%) had at least one positive viremia. After adjustment by confounders, the presence of the minor alleles of rs2071746 (HMOX1; T/T genotype OR 9.9 p < 0.0001), rs78958998 (probably associated with SERPING1 expression; A/T genotype OR 2.3, p = 0.04 and T/T genotype OR 12.9, p < 0.0001), and rs713400 (eQTL for TMPRSS2; C/T + T/T genotype OR 1.86, p = 0.10) were associated with higher risk of viremia, whereas the minor alleles of rs11052877 (CD69; A/G genotype OR 0.5, p = 0.04 and G/G genotype OR 0.3, p = 0.01), rs2660 (OAS1; A/G genotype OR 0.6, p = 0.08), rs896 (VIPR1; T/T genotype OR 0.4, p = 0.02) and rs33980500 (TRAF3IP2; C/T + T/T genotype OR 0.3, p = 0.01) were associated with lower risk of viremia. Conclusion: Genetic variants in HMOX1 (rs2071746), SERPING1 (rs78958998), TMPRSS2 (rs713400), CD69 (rs11052877), TRAF3IP2 (rs33980500), OAS1 (rs2660) and VIPR1 (rs896) could explain heterogeneity in SARS-CoV-2 viremia in our population.

The impact of "faster aspart" on blood glucose control in children and adolescents with type 1 diabetes treated using a sensor-augmented insulin pump.

BACKGROUND AND AIMS: Post-prandial glucose control is essential to achieve metabolic goals in patients with type 1 diabetes mellitus (T1DM). The new "faster aspart" insulin has a pharmacological profile noted for its faster absorption and onset of action, and increased early availability, resulting in improved blood glucose control after meals. The main objective of the study was to analyse the efficacy of "faster aspart" vs. "insulin aspart" in children and adolescents with DM1 on sensor-augmented pump treatment. PATIENTS AND METHODS: Multicentre, longitudinal and prospective analytical trial evaluating the use of faster aspart insulin for three months in children with T1DM with MiniMed640G® sensor-augmented pumps previously treated with aspart insulin. At the beginning and end of the study the following variables were analysed for subsequent comparison: mean sensor glucose, percentage of time in range, hypoglycaemia and hyperglycaemia, area under the curve (AUC) <70 and >180 mg/dL, mean sensor glucose pre- and postprandial in main meals, daily insulin requirements, basal/bolus percentage, and HbA1c. Acute complications, adverse events and satisfaction survey were assessed. RESULTS: The study included 32 patients with a mean of 13.49 ± 2.42 years of age and with T1DM of 7.0 ± 3.67 years of onset. The use of faster aspart was associated with lower time in hyperglycaemia >180 mg/dL (25.8 ± 11.3 vs. 22.4 ± 9.5; p = .011) and >250 mg/dL (5.2±4.9 vs. 4.0 ± 3.6; p = .04), lower AUC >180 mg/dL (10.8 ± 6.5 vs. 9.3 ± 6.1; p = .03), and increased time in range (71.4 ± 10.0 vs. 74.3 ± 9.2; p = .03). No significant changes in hypoglycaemia, HbA1c, insulin requirements, and basal/bolus percentages were detected. Faster aspart was safe and well-evaluated by patients and caregivers. CONCLUSIONS: Faster aspart achieves better glycaemic control by increasing glucose time in range in children and adolescents with T1DM on treatment with sensor-augmented pumps.

Medically unexplained pain complaints are associated with underlying unrecognized mood disorders in primary care.

BACKGROUND: Patients with chronic pain frequently display comorbid depression, but the impact of this concurrence is often underestimated and mistreated. The aim of this study was to determine the prevalence of unrecognized major depression and other mood disorders and comorbid unexplained chronic pain in primary care settings and to explore the associated factors.Also, to compare the use of health services by patients with unexplained chronic pain, both with and without mood disorder comorbidity. METHODS: A cross-sectional study was carried out in a sample of primary care centers. 3189 patients consulting for "unexplained chronic pain" were assessed by the Visual Analogue Scales (VAS) and the Primary Care Evaluation of Mental Disorders (PRIME-MD) questionnaire. RESULTS: We report: a) a high prevalence of unrecognized mood disorders in patients suffering from unexplained chronic pain complaints (80.4%: CI 95%: 79.0%; 81.8%); b) a greater susceptibility of women to mood disorders (OR adjusted = 1.48; CI 95%:1.22; 1.81); c) a direct relationship between the prevalence of mood disorders and the duration of pain (OR adjusted = 1.01; CI 95%: 1.01; 1.02) d) a higher comorbidity with depression if the pain etiology was unknown (OR adjusted = 1.74; CI 95%: 1.45; 2.10) and, e) an increased use of health care services in patients with such a comorbidity (p < 0.0001). CONCLUSIONS: The prevalence of undiagnosed mood disorders in patients with unexplained chronic pain in primary care is very high, leading to dissatisfaction with treatment processes and poorer outcomes. Consequently, it seems necessary to explore this condition more regularly in general practice in order to reach accurate diagnoses and to select the appropriate treatment.

Evaluation of therapeutic targeting of CCR7 in acute graft-versus-host disease.

Graft-versus-host disease (GVHD) is the main complication after allogeneic hematopoietic stem cell transplantation. We previously unveiled a correlation between proportions of C-C motif chemokine receptor 7 (CCR7)+ T cells in the apheresis and the risk of developing GVHD. We wanted to evaluate in vivo whether apheresis with low proportion of CCR7+ cells or treatment with an anti-human CCR7 monoclonal antibody (mAb) were suitable strategies to prevent or treat acute GVHD in preclinical xenogeneic models. Therapeutic anti-CCR7 mAb was the most effective strategy in both prophylactic and therapeutic settings where antibody drastically reduced in vivo lymphoid organ infiltration of donor CCR7+ T cells, extended lifespan and solved clinical signs. The antibody neutralized in vitro migration of naïve and central memory T cells toward CCR7 ligands and depleted target CCR7+ subsets through complement activation. Both mechanisms of action spared CCR7- subsets, including effector memory and effector memory CD45RA+ T cells which may mediate graft versus leukemia effect and immunity against infections. Accordingly, the numbers of donor CCR7+ T cells in the apheresis were not associated to cytomegalovirus reactivation or the recurrence of the underlying disease. These findings provide a promising new strategy to prevent and treat acute GVHD, a condition where new specific, safety and effective treatment is needed.

[The impact of «faster aspart¼ on blood glucose control in children and adolescents with type 1 diabetes treated using a sensor-augmented insulin pump]. / Impacto de faster aspart sobre el control glucémico en niños y adolescentes con diabetes tipo 1 en tratamiento con un sistema integrado.

BACKGROUND AND AIMS: Post-prandial glucose control is essential to achieve metabolic goals in patients with type 1 diabetes mellitus (T1DM). The new «faster aspart¼ insulin has a pharmacological profile noted for its faster absorption and onset of action, and increased early availability, resulting in improved blood glucose control after meals. The main objective of the study was to analyse the efficacy of «faster aspart¼ vs. «insulin aspart¼ in children and adolescents with DM1 on sensor-augmented pump treatment. PATIENTS AND METHODS: Multicentre, longitudinal and prospective analytical trial evaluating the use of faster aspart insulin for three months in children with T1DM with MiniMed640G® sensor-augmented pumps previously treated with aspart insulin. At the beginning and end of the study the following variables were analysed for subsequent comparison: mean sensor glucose, percentage of time in range, hypoglycaemia and hyperglycaemia, area under the curve (AUC) < 70 and > 180 mg/dL, mean sensor glucose pre and postprandial in main meals, daily insulin requirements, basal/bolus percentage, and HbA1c. Acute complications, adverse events and satisfaction survey were assessed. RESULTS: The study included 31 patients with a mean of 13.49 ± 2.42 years of age and with T1DM of 7.0 ± 3.67 years of onset. The use of faster aspart was associated with lower time in hyperglycaemia > 180 mg/dL (25.8 ± 11.3 vs. 22.4 ± 9.5; p = 0.011) and > 250 mg/dL (5.2 ± 4.9 vs. 4.0 ± 3.6; p = 0.04), lower AUC > 180 mg/dL (10.8 ± 6.5 vs. 9.3 ± 6.1; p = 0.03), and increased time in range (71.4 ± 10.0 vs. 74.3 ± 9.2; p = 0.03). No significant changes in hypoglycaemia, HbA1c, insulin requirements, and basal/bolus percentages were detected. Faster aspart was safe and well-evaluated by patients and caregivers. CONCLUSIONS: Faster aspart achieves better glycaemic control by increasing glucose time in range in children and adolescents with T1DM on treatment with sensor-augmented pumps.

A novel process of viral vector barcoding and library preparation enables high-diversity library generation and recombination-free paired-end sequencing.

Detailed characterization and mapping of oligonucleotide function in vivo is generally a very time consuming effort that only allows for hypothesis driven subsampling of the full sequence to be analysed. Recent advances in deep sequencing together with highly efficient parallel oligonucleotide synthesis and cloning techniques have, however, opened up for entirely new ways to map genetic function in vivo. Here we present a novel, optimized protocol for the generation of universally applicable, barcode labelled, plasmid libraries. The libraries are designed to enable the production of viral vector preparations assessing coding or non-coding RNA function in vivo. When generating high diversity libraries, it is a challenge to achieve efficient cloning, unambiguous barcoding and detailed characterization using low-cost sequencing technologies. With the presented protocol, diversity of above 3 million uniquely barcoded adeno-associated viral (AAV) plasmids can be achieved in a single reaction through a process achievable in any molecular biology laboratory. This approach opens up for a multitude of in vivo assessments from the evaluation of enhancer and promoter regions to the optimization of genome editing. The generated plasmid libraries are also useful for validation of sequencing clustering algorithms and we here validate the newly presented message passing clustering process named Starcode.