Development of pathophysiologically relevant models of sickle cell disease and β-thalassemia for therapeutic studies

Ex vivo cellular system that accurately replicates sickle cell disease and β-thalassemia characteristics is a highly sought-after goal in the field of erythroid biology. In this study, we present the generation of erythroid progenitor lines with sickle cell disease and β-thalassemia mutation using CRISPR/Cas9. The disease cellular models exhibit similar differentiation profiles, globin expression and proteome dynamics as patient-derived hematopoietic stem/progenitor cells. Additionally, these cellular models recapitulate pathological conditions associated with both the diseases. Hydroxyurea and pomalidomide treatment enhanced fetal hemoglobin levels. Notably, we introduce a therapeutic strategy for the above diseases by recapitulating the HPFH3 genotype, which reactivates fetal hemoglobin levels and rescues the disease phenotypes, thus making these lines a valuable platform for studying and developing new therapeutic strategies. Altogether, we demonstrate our disease cellular systems are physiologically relevant and could prove to be indispensable tools for disease modeling, drug screenings and cell and gene therapy-based applications.

Impact of COVID-19 outbreak on healthcare workers in a Tertiary Healthcare Center in India: a cross sectional study

Numerous speculations have continually emerged, trying to explore the association between COVID-19 infection and a varied range of demographic and clinical factors. Frontline healthcare workers have been the primary group exposed to this infection, and there have been limited global research that examine this cohort. However, while there are a few large studies conducted on Indian healthcare professionals to investigate their potential risk and predisposing factors to COVID-19 infection, to our knowledge there are no studies evaluating the development of long COVID in this population. This cross-sectional study systematically utilized the demographic and clinical data of 3329 healthcare workers (HCW) from a tertiary hospital in India to gain significant insights into the associations between disease prevalence, severity of SARS-Cov-2 infection and long COVID. Most of the study population was found to be vaccinated (2,615, 78.5%), while 654 (19.65%) HCWs were found to be SARS-CoV-2 positive at least once. Of the infected HCWs, 75.1% (491) did not require hospitalization, whereas the rest were hospitalized for an average duration of 9 days. A total of 206 (6.19%) individuals were found to be suffering from long COVID. Persistent weakness/tiredness was the most experienced long-COVID symptom, while females (1.79, 1.25-2.57), individuals who consumed alcohol (1.85, 1.3-2.64) or had blood group B (1.9, 1.33-2.7) were at a significantly higher risk for developing long COVID.

Systematic In-Silico Evaluation of the Diagnostic Impact of Mpox Genome Variants in the Current Outbreak

BACKGROUND AND OBJECTIVE

The rapid rate at which the current mpox virus outbreak has spread across the globe has led the World Health Organization to declare it a Public Health Emergency of International Concern. Polymerase chain reaction-based methods are one of the cornerstones for effective molecular detection of viruses including mpox virus. Genetic variants in primer binding sites are known to impact the efficiency of polymerase chain reaction and therefore diagnosis. Here we have analyzed the genetic variants and their impact on efficient binding of oligonucleotides used in diagnostics.

METHODS

In this study, we have systematically collected primers and probes used in the detection of mpox virus from published literature and public resources, and assessed the impact of primer binding region genetic variants in the detection of mpox virus by analysing the thermodynamic parameters, Gibbs free energy and melting temperature. These were calculated using the nearest neighbour method for variants in mpox virus genomes available and the deviation in parameters was computed with respect to the reference genome sequence.

RESULTS

We have identified 170 genetic variations that fall within the oligo binding region in 1176 mpox virus genomes out of which five oligos showed at least a 2 °C decrease in melting temperature, which could potentially affect the diagnostic efficacy.

CONCLUSIONS

Our analysis shows the importance of continuous monitoring of mpox virus detection primer efficacy and provides the list of oligos with potentially reduced detection efficiency in the current mpox virus outbreak.

Genomic characterization and epidemiology of an emerging SARS-CoV-2 variant in Delhi, India

Delhi, the national capital of India, experienced multiple severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreaks in 2020 and reached population seropositivity of >50% by 2021. During April 2021, the city became overwhelmed by COVID-19 cases and fatalities, as a new variant, B.1.617.2 (Delta), replaced B.1.1.7 (Alpha). A Bayesian model explains the growth advantage of Delta through a combination of increased transmissibility and reduced sensitivity to immune responses generated against earlier variants (median estimates: 1.5-fold greater transmissibility and 20% reduction in sensitivity). Seropositivity of an employee and family cohort increased from 42% to 87.5% between March and July 2021, with 27% reinfections, as judged by increased antibody concentration after a previous decline. The likely high transmissibility and partial evasion of immunity by the Delta variant contributed to an overwhelming surge in Delhi.

Variants of concern responsible for SARS-CoV-2 vaccine breakthrough infections from India

Emerging reports of SARS‐CoV‐2 breakthrough infections entail methodical genomic surveillance for determining the efficacy of vaccines. This study elaborates genomic analysis of isolates from breakthrough infections following vaccination with AZD1222/Covishield and BBV152/Covaxin. Variants of concern B.1.617.2 and B.1.1.7 responsible for cases surge in April–May 2021 in Delhi, were the predominant lineages among breakthrough infections.