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Giribhattanavar, P.

Publications and source records attributed to Giribhattanavar, P..

2 recordsLinked to original sources

Cytokine Dynamics and Oxidative Stress in Host Cells Stimulated with Drug-Resistant and Sensitive Mycobacterium tuberculosis Isolates

BackgroundThe immune response to Mycobacterium tuberculosis (M. tuberculosis) is central to the pathogenesis of tuberculosis (TB), yet the immune dynamics induced by drug-resistant strains remain underexplored. Understanding the hosts immune response to both drug-sensitive and drug-resistant M. tuberculosis isolates is crucial for elucidating the mechanisms of pathogenesis and resistance. This study aims to assess the cellular immune responses, including PBMC proliferation, cytokine secretion (IL-4 and IL-17a), and reactive oxygen species (ROS) production in response to live drug-sensitive and drug-resistant M. tuberculosis clinical isolates. MethodsPeripheral blood mononuclear cells (PBMCs) from PPD-negative and PPD-positive healthy volunteers were stimulated with live M. tuberculosis isolates, including MDR, SI-resistant, and sensitive strains. The immune responses were assessed by evaluating cell proliferation, secretion of IL-4 and IL-17a cytokines, and ROS production over a 9-day period. ResultsPBMCs from PPD-positive individuals exhibited a higher proliferative response compared to PPD-negative individuals, indicating more robust immune memory. IL-4 secretion was low but varied among samples, with higher levels observed in response to MDR isolates, suggesting a potential role in immunopathology. IL-17a levels increased over time, particularly in PPD-positive individuals, and MDR strains elicited a stronger response than sensitive isolates. ROS production was significantly elevated in response to resistant strains, reflecting the hosts oxidative defense mechanisms. ConclusionThis study demonstrates distinct immune responses to drug-resistant M. tuberculosis isolates, with variations in cell proliferation, cytokine secretion, and ROS production. These findings provide insights into the immune dynamics during infection with resistant strains and underscore the importance of genotype-environment interactions in TB pathogenesis. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=100 SRC="FIGDIR/small/626310v1_ufig1.gif" ALT="Figure 1"> View larger version (26K): org.highwire.dtl.DTLVardef@1bb9ad6org.highwire.dtl.DTLVardef@1b268e7org.highwire.dtl.DTLVardef@52800org.highwire.dtl.DTLVardef@85234b_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

Exploring variations in lipids among drug-resistant and sensitive Mycobacterium tuberculosis by Thin layer chromatography and mass spectrometry

Mycobacterium tuberculosis (M.tb) lipids are important in the host-pathogen interplay, variation in the lipids organization of cell wall can act as an adaptive response. Specific cell wall structures can possibly result in suboptimal intracellular concentrations of anti-TB drugs, which favors the acquisition of drug resistance. Therefore, lipids from M.tb (drug resistant and sensitive) were analyzed by 2D-thin layer chromatography and mass spectrometry. GraphPad Prism was used to perform Mann Whitney-U test to determine the statistical significance. Difference observed for total lipid content among different resistant isolates was insignificant. However, increase in phospholipids was identified in multi-drug resistant (MDR) isolate compared to sensitive isolate. Isoniazid, streptomycin-isoniazid, and isoniazid-ethambutol resistant isolates showed increased alpha-mycolic acids. MDR isolate showed a marginal decrease in alpha- and keto-form. Mycolipenic acid was seen only in sensitive isolate, and mycosanoic acids were observed in all the resistant isolates. Among the resistant isolates, there was an insignificant increase in the total phthiocerol dimycocerosates and sulfolipids. Drug resistance was associated with compositional imbalance of lipids. However, investigations to determine whether the changes notices are induced by the drugs is to be explored, which could give an insight into the drug resistant organisms pathogenesis.

microbiology↗