Distinct host-immune response toward species related intracellular mycobacterial killing : a transcriptomic study

CITATION: Madhvi Abhilasha et al. 2020. Distinct host-immune response toward species related intracellular mycobacterial killing : a transcriptomic study. Virulence, 11(1):170-182, doi:10.1080/21505594.2020.1726561.The original publication is availablle at: https://www.ncbi.nlm.nih.govThe comparison of the host immune response when challenged with pathogenic and nonpatho- genic species of mycobacteria can provide answers to the unresolved question of how pathogens subvert or inhibit an effective response. We infected human monocyte derived macrophages (hMDMs) with different species of mycobacteria, in increasing order of pathogenicity, i.e. M. smegmatis, M. bovis BCG, and M. tuberculosis R179 that had been cultured in the absence of detergents. RNA was isolated post-infection and transcriptomic analysis using amplicons (Ampliseq) revealed 274 differentially expressed genes (DEGs) across three species, out of which we selected 19 DEGs for further validation. We used qRT-PCR to confirm the differential expression of 19 DEGs. We studied biological network through Ingenuity Pathway Analysis® (IPA) which revealed up-regulated pathways of the interferon and interleukin family related to the killing of M. smegmatis. Apart from interferon and interleukin family, we found one up-regulated (EIF2AK2) and two down-regulated (MT1A and TRIB3) genes as unique potential targets found by Ampliseq and qRT-PCR which may be involved in the intracellular mycobacterial killing. The roles of these genes have not previously been described in tuberculosis. Multiplex ELISA of culture supernatants showed increased host immune response toward M. smegmatis as compared to M. bovis BCG and M.tb R179. These results enhance our understanding of host immune response against M.tb infection.Publisher's versio

Clinical utility of C-reactive protein-based triage for presumptive pulmonary tuberculosis in South African adults.

BACKGROUND: Identification of an accurate, low-cost triage test for pulmonary TB among people presenting to healthcare facilities is an urgent global research priority. We assessed the diagnostic accuracy and clinical utility of C-reactive protein (CRP) for TB triage among symptomatic adult outpatients, irrespective of HIV status. METHODS: We prospectively enrolled adults reporting at least one (for people with HIV) or two (for people without HIV) symptoms of cough, fever, night sweats, or weight loss at two TB clinics in Cape Town, South Africa. Participants provided sputum for culture and Xpert MTB/RIF Ultra. We evaluated the diagnostic accuracy of CRP (measured using a laboratory-based assay) against a TB-culture reference standard as the area under the receiver operating characteristic curve (AUROC), and sensitivity and specificity at pre-specified thresholds. We assessed clinical utility using decision curve analysis and benchmarked against WHO recommendations. RESULTS: Of 932 included individuals, 255 (27%) had culture-confirmed pulmonary TB and 389 (42%) were living with HIV. CRP demonstrated an AUROC of 0·80 (95% confidence interval 0·77-0·83), with sensitivity 93% (89-95%) and specificity 54% (50-58%) using a primary cut-off of ≥10 mg/L. Performance was similar among people with HIV to those without. In decision curve analysis, CRP-based triage offered greater clinical utility than confirmatory testing for all up to a number willing to test threshold of 20 confirmatory tests per true positive pulmonary TB case diagnosed (threshold probability 5%). If it is possible to perform more confirmatory tests than this, a 'confirmatory test for all' strategy performed better. CONCLUSIONS: CRP achieved the WHO-defined sensitivity, but not specificity, targets for a triage test for pulmonary TB and showed evidence of clinical utility among symptomatic outpatients, irrespective of HIV status. FUNDING: South African Medical Research Council, EDCTP2, Royal Society Newton Advanced Fellowship, Wellcome Trust, National Institute of Health Research, Royal College of Physicians

Impact of nicotine replacement therapy as an adjunct to anti-tuberculosis treatment and behaviour change counselling in newly diagnosed pulmonary tuberculosis patients: an open-label, randomised controlled trial.

We evaluated the impact of intensive smoking cessation activities as an adjunct to anti-tuberculosis treatment on patient-related treatment outcomes. In this open-label, randomised controlled trial, self-reporting smokers with pulmonary tuberculosis who initiated standard anti-tuberculosis treatment were randomised to either nicotine replacement therapy and behaviour change counselling (n = 400) or counselling alone (n = 400) provided at baseline and two follow-up visits. The primary outcomes were change in TBscore at 24-weeks and culture conversion at 8-weeks. Biochemical smoking quit rates defined as serum cotinine levels <10 ng/mL and/or exhaled carbon monoxide levels <6 ppm (47·8% vs 32·4%, p-value =< 0·001) and self-reported quit rates (69.3% vs 38·7%, p-value =< 0·001) were significantly higher in the intervention arm at 24-weeks. Though the TBscores at 24 weeks (95% CI) were lower in the intervention arm [2·07 (1·98, 2·17) versus 2.12 (2·02, 2·21)], the difference was not clinically meaningful. Patients in the control arm required treatment extension more often than intervention arm (6·4% vs 2·6%, p-value = 0·02). Combining nicotine replacement therapy with behaviour change counselling resulted in significantly higher quit rates and lower cotinine levels, however, impact on patient-related (TBscore) or microbiological outcomes (culture conversion) were not seen

Comparison of human monocyte derived macrophages and THP1-like macrophages as in vitro models for M. tuberculosis infection

CITATION: Madhvi, A., et al. 2019. Comparison of human monocyte derived macrophages and THP1-like macrophages as in vitro models for M. tuberculosis infection. Comparative Immunology, Microbiology and Infectious Diseases, 67:101355, doi:10.1016/j.cimid.2019.101355.The original publication is available at https://www.sciencedirect.comMacrophages are the preferential cell types to study various aspects of mycobacterial infection. Commonly used infection models for in-vitro studies are primary macrophages such as human monocyte derived macrophages (hMDMs) and macrophage like cell lines (THP-1). It is not clear if commercially available THP-1 cells can be used as hMDMs alternative for in-vitro M.tb infection experiments. We conducted a detailed investigation of the hMDM and THP-1 response to mycobacterial infection on a comparative basis and assess the most crucial aspects of infection which are most commonly studied. We assessed mycobacterial uptake and intracellular growth over time of a pathogenic drug-resistant and drug-susceptible M.tb strains (R179 and H37Rv) through colony forming units (CFUs). Both strains depicted similar uptake and intracellular growth in hMDMs and THP-1 macrophages over time (R179, p=0.954) (H37Rv, p=0.922). Cytotoxicity assays revealed a consistent viability up to day 16 post-infection across the strains in both THP-1 and hMDMs (R179, p=0.271) (H37Rv, p=0.068). Interestingly, both cell lines showed similar mycobacterial uptake and cellular viability in both susceptible as well as resistant M.tb strains. Cytokine/chemokine mRNA analysis through qPCR found no difference between cell types. Further, cytokine secretion measured through Luminex revealed no difference across the strains. Also, cytokine secretion analysis showed no difference in both cell lines across strains. In conclusion, our study shows that THP-1 and hMDMs bacterial uptake, viability and host response to drug-susceptible and drug-resistant mycobacterial infections are similar. Therefore, present study demonstrate that THP-1 cells are suitable substitutes for hMDMs for in-vitro M.tb infection experiments.https://www.sciencedirect.com/science/article/pii/S0147957119301523Publisher's versio

Prevalence and risk factors of syndrome Z in Urban Indians

Background Syndrome Z is defined as the co-occurrence of obstructive sleep apnea (OSA) and metabolic syndrome. There is a paucity of information on the magnitude of syndrome Z in the community and the factors associated with it. Methods We conducted a two-stage, cross-sectional, community-based study in four different socioeconomic zones of the South Delhi district, India, from April 2005 through June 2007. In stage 1, a systematic random sample of subjects of either gender aged 30-65 years were administered a questionnaire by door-to-door survey. Subjects that responded were classified as habitual and non-habitual snorers. In stage 2, all the habitual and 10% of randomly selected non-habitual snorers were invited for overnight polysomnography and evaluation for metabolic syndrome. The National Cholesterol Education Program-Adult Treatment Panel III (NCEP-ATPIII) criteria were used to define metabolic syndrome. Results Of the 2860 subjects approached, 2505 (88%) completed stage 1; 452 (18%) were habitual snorers. In stage 2, OSA (defined as apnea-hypopnea index ≥5) was observed in 94 (32.4%) of 290 habitual snorers and 3 (4%) of 75 non-habitual snorers. Seventy (77%) of the 91 habitual snorers with OSA also had metabolic syndrome; none of the non-habitual snorers with OSA had metabolic syndrome. The estimated population prevalence of metabolic syndrome was 43% [95% CI: (41.0-44.9%)] and syndrome Z was 4.5% (95% CI: 3.7-5.3). On multivariable analysis, age [OR: 1.05 (1.00-1.09)], male gender [OR: 5.64 (2.06-15.49)], percent body fat [OR: 1.08 (1.04-1.13)] and ΔSaO2 (%) (defined as the difference between baseline and minimum SaO2 during overnight sleep study) [OR: 5.80 (2.36-14.26), 17.70 (5.97-52.17) and 57.1 (19.12-170.40) for 10-20%, 20-30% and &gt;30% reduction respectively as compared to &lt;10% reduction] were independently associated with syndrome Z. Conclusions To the best of our knowledge, this is the first population-based study on the prevalence and risk factors of syndrome Z, and it reveals that a considerable proportion of community-dwelling northern Indian adults have syndrome Z. Age, male gender, percent body fat and severity of nocturnal desaturation were independent risk factors for syndrome Z

Fluorescent carbon nanomaterials from coal and its derivatives: structure, properties, and applications

Coal is a cheap and sustainable precursor for the preparation of fuorescent carbon nanomate�rials (FCNMs). Based on the size and morphology, these nanomaterials are classifed as carbon quan�tum dots (CQDs), carbon nanotubes (CNTs), carbon nanofbers (CNFs), carbon nanosheets (CNSs), graphene quantum dots (GQDs), carbon polymer dots (CPDs) etc. The FCNMs have sparked inter�est because of their distinctive fuorescence, efec�tive catalysis, water solubility, biocompatibility, ease of surface functionalization, cost-efective synthesis, photostability, and other potential benefts for various advanced applications. A substantial percentage of the scientifc community has been driven by a strong desire to prepare carbon nanomaterials (CNMs) using environmentally acceptable and low-cost synthe�sis methods. The precursors used in the preparation of carbon-based nanomaterials are critical to the technology’s future success. Most traditional syn�thesis procedures use high-cost carbon feedstocks like hydrocarbons and graphite, limiting their com�mercialization. In this review, coal is used as starting material for the synthesis of FCNMs and is applied in various current felds.Highlights • Coal and its derivatives derived fuo�rescent carbon nanomaterials are discussed. • Diferent type of methodology basically top-down and bottom-up for the preparation of fuorescent car�bon nanomaterials are described. • The physical and optical properties of fuorescent carbon nanomaterials are discussed. • The origin of fuorescence on coal-based nanomate�rials have been discussed. • The multifunctional applications of fuorescent car�bon nanomaterials are summarized in detail. • The advantage, challenges and future prospects of fuorescent Carbon Nanomaterials from Coal is discusse

Aetiology, outcomes &amp; predictors of mortality in acute respiratory distress syndrome from a tertiary care centre in north India.

Background &amp; objectivesAcute respiratory distress syndrome (ARDS) is a common disorder in critically ill patients and is associated with high mortality. There is a paucity of literature on this condition from developing countries. This prospective observational study was designed to find out the aetiology, outcomes and predictors of mortality in ARDS.MethodsSixty four consecutive patients who satisfied American-European Consensus Conference (AECC) definition of ARDS from medical Intensive Care Unit (ICU) of a tertiary care centre in New Delhi, India, were enrolled in the study. Demographic, biochemical and ventilatory variables were recorded for each patient. Baseline measurements of serum interleukin (IL)-1β, IL-6, tumour necrosis factor-alpha (TNF-α), procalcitonin (PCT) and high sensitivity C-reactive protein (hsCRP) were performed.ResultsCommon causes of ARDS included pneumonia [44/64 (68.7%)], malaria [9/64 (14.1%)] and sepsis [8/64 (12.5%]. Eight of the 64 (12.5%) patients had ARDS due to viral pneumonia. The 28-day mortality was 36/64 (56.2%).Independent predictors of mortality included non-pulmonary organ failure, [Hazard ratio (HR) 7.65; 95% CI 0.98-59.7, P=0.05], Simplified Acute Physiology Score (SAPS-II) [HR 2.36; 95% CI 1.14-4.85, P=0.02] and peak pressure (P peak ) [HR 1.13; 95% CI 1.00-1.30, P = 0.04] at admission.Interpretation &amp; conclusionsBacterial and viral pneumonia, malaria and tuberculosis resulted in ARDS in a considerable number of patients. Independent predictors of mortality included non-pulmonary organ failure, SAPS II score and P peak at baseline. Elevated levels of biomarkers such as TNF-α, PCT and hsCRP at admission might help in identifying patients at a higher risk of mortality

Aetiology, outcomes & predictors of mortality in acute respiratory distress syndrome from a tertiary care centre in north India

Background & objectives: Acute respiratory distress syndrome (ARDS) is a common disorder in critically ill patients and is associated with high mortality. There is a paucity of literature on this condition from developing countries. This prospective observational study was designed to find out the aetiology, outcomes and predictors of mortality in ARDS. Methods: Sixty four consecutive patients who satisfied American-European Consensus Conference (AECC) definition of ARDS from medical Intensive Care Unit (ICU) of a tertiary care centre in New Delhi, India, were enrolled in the study. Demographic, biochemical and ventilatory variables were recorded for each patient. Baseline measurements of serum interleukin (IL)-1β, IL-6, tumour necrosis factor-alpha (TNF-α), procalcitonin (PCT) and high sensitivity C-reactive protein (hsCRP) were performed. Results: Common causes of ARDS included pneumonia [44/64 (68.7%)], malaria [9/64 (14.1%)] and sepsis [8/64 (12.5%]. Eight of the 64 (12.5%) patients had ARDS due to viral pneumonia. The 28-day mortality was 36/64 (56.2%).Independent predictors of mortality included non-pulmonary organ failure, [Hazard ratio (HR) 7.65; 95% CI 0.98-59.7, P=0.05], Simplified Acute Physiology Score (SAPS-II) [HR 2.36; 95% CI 1.14-4.85, P=0.02] and peak pressure (P peak ) [HR 1.13; 95% CI 1.00-1.30, P = 0.04] at admission. Interpretation & conclusions: Bacterial and viral pneumonia, malaria and tuberculosis resulted in ARDS in a considerable number of patients. Independent predictors of mortality included non-pulmonary organ failure, SAPS II score and P peak at baseline. Elevated levels of biomarkers such as TNF-α, PCT and hsCRP at admission might help in identifying patients at a higher risk of mortality

Aetiology, outcomes &amp; predictors of mortality in acute respiratory distress syndrome from a tertiary care centre in north India.

Background &amp; objectivesAcute respiratory distress syndrome (ARDS) is a common disorder in critically ill patients and is associated with high mortality. There is a paucity of literature on this condition from developing countries. This prospective observational study was designed to find out the aetiology, outcomes and predictors of mortality in ARDS.MethodsSixty four consecutive patients who satisfied American-European Consensus Conference (AECC) definition of ARDS from medical Intensive Care Unit (ICU) of a tertiary care centre in New Delhi, India, were enrolled in the study. Demographic, biochemical and ventilatory variables were recorded for each patient. Baseline measurements of serum interleukin (IL)-1β, IL-6, tumour necrosis factor-alpha (TNF-α), procalcitonin (PCT) and high sensitivity C-reactive protein (hsCRP) were performed.ResultsCommon causes of ARDS included pneumonia [44/64 (68.7%)], malaria [9/64 (14.1%)] and sepsis [8/64 (12.5%]. Eight of the 64 (12.5%) patients had ARDS due to viral pneumonia. The 28-day mortality was 36/64 (56.2%).Independent predictors of mortality included non-pulmonary organ failure, [Hazard ratio (HR) 7.65; 95% CI 0.98-59.7, P=0.05], Simplified Acute Physiology Score (SAPS-II) [HR 2.36; 95% CI 1.14-4.85, P=0.02] and peak pressure (P peak ) [HR 1.13; 95% CI 1.00-1.30, P = 0.04] at admission.Interpretation &amp; conclusionsBacterial and viral pneumonia, malaria and tuberculosis resulted in ARDS in a considerable number of patients. Independent predictors of mortality included non-pulmonary organ failure, SAPS II score and P peak at baseline. Elevated levels of biomarkers such as TNF-α, PCT and hsCRP at admission might help in identifying patients at a higher risk of mortality

Clinical utility of C-reactive protein-based triage for presumptive pulmonary tuberculosis in South African adults

BACKGROUND: Identification of an accurate, low-cost triage test for pulmonary TB among people presenting to healthcare facilities is an urgent global research priority. We assessed the diagnostic accuracy and clinical utility of C-reactive protein (CRP) for TB triage among symptomatic adult outpatients, irrespective of HIV status. METHODS: We prospectively enrolled adults reporting at least one (for people with HIV) or two (for people without HIV) symptoms of cough, fever, night sweats, or weight loss at two TB clinics in Cape Town, South Africa. Participants provided sputum for culture and Xpert MTB/RIF Ultra. We evaluated the diagnostic accuracy of CRP (measured using a laboratory-based assay) against a TB-culture reference standard as the area under the receiver operating characteristic curve (AUROC), and sensitivity and specificity at pre-specified thresholds. We assessed clinical utility using decision curve analysis and benchmarked against WHO recommendations. RESULTS: Of 932 included individuals, 255 (27%) had culture-confirmed pulmonary TB and 389 (42%) were living with HIV. CRP demonstrated an AUROC of 0·80 (95% confidence interval 0·77–0·83), with sensitivity 93% (89–95%) and specificity 54% (50–58%) using a primary cut-off of ≥10mg/L. Performance was similar among people with HIV to those without. In decision curve analysis, CRP-based triage offered greater clinical utility than confirmatory testing for all up to a number willing to test threshold of 20 confirmatory tests per true positive pulmonary TB case diagnosed (threshold probability 5%). If it is possible to perform more confirmatory tests than this, a ‘confirmatory test for all’ strategy performed better. CONCLUSIONS: CRP achieved the WHO-defined sensitivity, but not specificity, targets for a triage test for pulmonary TB and showed evidence of clinical utility among symptomatic outpatients, irrespective of HIV status