Exosomes and HIV-1 Association in AIDS-Defining Patients

Exosomes are membranous nanovesicles of endocytic origin that help to facilitate cell-to-cell communication by transporting cellular cargo locally or systemically to a recipient cell. These are subsequently fused and internalised by recipient cells. Exosomes are secreted from all cell types in HIV-1 infected patients. Recent studies reveal that exosomes from various sources modulate the pathophysiology of HIV-1, and conversely, exosomes are also targeted by HIV-1 factors. Semen or plasma exosomes could suppress/inhibit HIV-1 replication in humans and rodent models. Exosomal cargo components could be used as a biomarker in HIV-1patients and AIDS-defining patients. Exosome in semen and plasma is a useful tool for the diagnosis of HIV-1 and an alternative therapeutic tool for antiretroviral therapy

Genome Sequencing of Polydrug-, Multidrug-, and Extensively Drug-Resistant Mycobacterium tuberculosis Strains from South India.

The genomes of 16 clinical Mycobacterium tuberculosis isolates were subjected to whole-genome sequencing to identify mutations related to resistance to one or more anti-Mycobacterium drugs. The sequence data will help in understanding the genomic characteristics of M. tuberculosis isolates and their resistance mutations prevalent in South India.This publication presents research supported by the MRC-DBT-funded partnership between the National Institute for Research in Tuberculosis, Chennai, India (Indian Council of Medical Research, New Delhi 5/2-8/LDCE/2014 for S.K., Department of Biotechnology [BT/IN/DBT-MRC (UK)/12/SS/2015-2016] for D.N., M.N., S.P.T., S.S., and U.D.R.) and the University of Cambridge (UK Medical Research Council [MR/N501864/1] for N.K. and S.P.)

Prevalence of Tuberculosis Infection and Disease Among Homeless Persons Staying in NGO Shelters in Chennai

Latent tuberculosis infection (LTBI) is a inactive stage after being infected with Mycobacterium tuberculosis and it reactivates into pulmonary tuberculosis (PTB). This study was to estimate the prevalence of LTBI in homeless persons staying in 13 shelters run by NGOs in Chennai metro city, India. A cross-sectional survey was conducted from January to April 2018. All inmates aged 15 years and above were screened for PTB infection using tuberculin skin test (TST) and disease smear and culture examinations. Out of a total of 1,068 registered, 1,016 persons were screened for PTB disease and 818 persons for LTBI. Among them, PTB was detected in two persons and TST was positive in 275 persons. Univariate and multivariate analyses were performed to find out the factors associated with LTBI. It was found that LTBI is significantly associated with male gender, aged more than 40 years and with chest X-ray TB lesions. This study finding highlights that low prevalence of TB disease and one third of homeless persons infected with tuberculosis. Our finding suggests that there is a need for prevention interventions to eliminate TB in this key populatio

Differential Frequencies of Intermediate Monocyte Subsets Among Individuals Infected With Drug-Sensitive or Drug-Resistant Mycobacterium tuberculosis

The rampant increase in drug-resistant tuberculosis (TB) remains a major challenge not only for treatment management but also for diagnosis, as well as drug design and development. Drug-resistant mycobacteria affect the quality of life owing to the delayed diagnosis and require prolonged treatment with multiple and toxic drugs. The phenotypic modulations defining the immune status of an individual during tuberculosis are well established. The present study aims to explore the phenotypic changes of monocytes & dendritic cells (DC) as well as their subsets across the TB disease spectrum, from latency to drug-sensitive TB (DS-TB) and drug-resistant TB (DR-TB) using traditional immunophenotypic analysis and by uniform manifold approximation and projection (UMAP) analysis. Our results demonstrate changes in frequencies of monocytes (classical, CD14(++)CD16(-), intermediate, CD14(++)CD16(+) and non-classical, CD14(+/-)CD16(++)) and dendritic cells (DC) (HLA-DR(+)CD11c(+) myeloid DCs, cross-presenting HLA-DR(+)CD14(-)CD141(+) myeloid DCs and HLA-DR(+)CD14(-)CD16(-)CD11c(-)CD123(+) plasmacytoid DCs) together with elevated Monocyte to Lymphocyte ratios (MLR)/Neutrophil to Lymphocyte ratios (NLR) and alteration of cytokine levels between DS-TB and DR-TB groups. UMAP analysis revealed significant differential expression of CD14(+), CD16(+), CD86(+) and CD64(+) on monocytes and CD123(+) on DCs by the DR-TB group. Thus, our study reveals differential monocyte and DC subset frequencies among the various TB disease groups towards modulating the immune responses and will be helpful to understand the pathogenicity driven by Mycobacterium tuberculosis

Whole-Genome Sequencing of a Mycobacterium orygis Strain Isolated from Cattle in Chennai, India.

Here, we report the isolation of Mycobacterium orygis from dairy cattle in Chennai, India. Spoligotyping assigned the isolate to spoligotype 587 (ST587), which belongs to M. orygis This species was confirmed as M. orygis using whole-genome sequencing