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Pillai, D.

Publications and source records attributed to Pillai, D..

4 recordsLinked to original sources

Detection of five viruses commonly implicated with Bovine Respiratory Disease using loop-mediated isothermal amplification

Herein, we present novel quantitative loop-mediated isothermal amplification (qLAMP) and reverse-transcription qLAMP (RT-qLAMP) assays for the detection of five viruses commonly implicated with the onset and progression of bovine respiratory disease (BRD): Bovine Alphaherpesvirus Type 1 (BHV-1), Bovine Adenovirus Type 3 (BAV-3), Bovine Respiratory Syncytial Virus (BRSV), Bovine Viral Diarrhea Virus Type 1 (BVDV-1), and Bovine Parainfluenza Virus Type 3 (BPIV-3). Using contrived samples spiked with whole viruses, we found that our extraction-free assays have limits of detection between 30 and 1,057 copies per reaction (1.8% final sample concentration) with minimal sample processing. Using dual-tipped swabs and 1.4 mL resuspension volumes, these limits of detection are on the order of 2 x 105 copies per swab for BAV-3 and BHV-1 and between 6.31 x 106 to 8.22 x 106 copies per swab in the case of BPIV-3, BRSV, and BVDV-1. Analytical sensitivities ranged from 73 - 100% and analytical specificities ranged from 90 - 100%. Additionally, we introduced a streamlined pipeline to minimize the experimental workload to design, screen, select, and characterize LAMP performance for developing assays. The assays targeting these BRD viruses can be utilized to develop colorimetric LAMP assays that enable the sensitive and specific detection of these viruses chute side to aid in diagnosing and treating BRD. The associated development pipeline enables more rapid development of LAMP-based diagnostic tools targeting emerging pathogens.

bioengineering↗

Development and Evaluation of Novel Quantitative PCR (qPCR) and Loop-Mediated Isothermal Amplification (LAMP) Assays for Bovine Adenovirus Type 7

Herein, we report the development of molecular assays for the specific detection of bovine adenovirus type 7 (BAV-7), a prevalent pathogen associated with bovine respiratory disease (BRD). To overcome the limitations of the current diagnostic methods, we developed and optimized a TaqMan quantitative polymerase chain reaction (qPCR) assay with a limit of detection (LOD) of 50 copies per reaction (10 copies/{micro}L) and 100% analytical specificity, showing no cross-reactivity with nine other viral pathogens commonly linked to BRD. Additionally, we designed a fluorescent quantitative loop-mediated isothermal amplification (qLAMP) assay demonstrating equivalent LOD and specificity. Both assays were evaluated using 24 bovine nasal swabs from BRD animals, revealing a 92% agreement between qPCR and qLAMP results. These assays provide powerful tools for advancing our understanding of BAV-7 epidemiology and improving disease management strategies. The qLAMP assay, with its rapid and isothermal amplification, presents potential for future development as a field-deployable diagnostic tool to enable timely detection of BAV-7 in cattle.

bioengineering↗

Dysregulated airway epithelial antiviral immunity in Down Syndrome impairs type III IFN response and amplifies airway inflammation during RSV infection.

Trisomy 21 (TS21), also known as Down syndrome (DS), increases pediatric mortality risk from respiratory syncytial virus (RSV) by nine-fold, yet its underlying immunological basis remains unclear. Here, we investigated RSV-induced immunological responses in TS21 airway epithelial cells (AECs), the primary site of respiratory virus entry and host defense. TS21 AECs exhibit hyperactive interferon (IFN) signaling and reduced RSV infectivity, but they also show impaired type-III IFN responses during viral infection. Furthermore, TS21 AECs demonstrate heightened production of proinflammatory mediators CXCL5 and CXCL10 both before and after RSV exposure. Infants with DS suffering from severe viral bronchiolitis demonstrate dysregulated airway immune responses in vivo, characterized by diminished type-III IFN levels and increased CXCL5/CXCL10 secretion. Our results indicate that RSV severity in DS is not due to impaired viral control but to dysregulated airway proinflammatory responses, offering new therapeutic opportunities to mitigate the severity of RSV infection in children with DS.

immunology↗

Pro-inflammatory Pathways Contribute to Pathogenesis of Clostridioides difficile Infection in a Murine Model - A Spatial Transcriptomics Study

Clostridioides difficile (C. difficile) is a common cause of antibiotic-induced diarrhea and causes the highest number of nosocomial infections. Only two antibiotics are currently recommended for treating C. difficile infection (CDI), which may contribute to unsatisfactory treatment outcomes and an increased likelihood of recurrence. Clostridioides difficile exists as a non-pathogenic member of the human intestinal microbiome in 10-20% of the population, a phenomenon observed in mouse models after infection with bacterial spores. In this study, we aim to evaluate the difference in gene expression between symptomatic and asymptomatic mice after infection with C. difficile using spatial transcriptomics analysis. We also aim to evaluate the spatial aspect of altered genes between different layers of intestinal mucosa (superficial vs deep) and identify the key pathways. Formalin-fixed paraffin-embedded (FFPE) intestinal sections were utilized for analysis using NanoString platform to evaluate differential gene expressions in the caecum and colon. The IL-17 pathway, including Lcn2, Cxcl2, and S100a8 genes, was significantly upregulated in symptomatic mice. The IL-17 signaling pathway activated downstream signaling through NF-{kappa}B and MAPK pathways. Gene expression was significantly altered between the intestinal superficial and deep mucosal layers, highlighting layer-specific differences in gene expression patterns in the intestines of symptomatic and asymptomatic mice. Gene expression patterns in the enteric mucosa explain several clinical signs and lesions in CDI mice.

microbiology↗