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Following infection with SARS-CoV-2, cellular components of the adaptive immune system play a crucial role in eliminating the virus. Specifically, virus-specific CD4+ and CD8+ T cells generate effector cytokines and display cytotoxic activity. A number of studies carried out during the COVID-19 pandemic highlighted the importance of CD4+ T cells, CD8+ T cells, and memory cells in this process. T-cell responses emerge early and contribute to protection, but are comparatively impaired in severe cases, often accompanied by intense activation or lymphopenia. Since December 2020, SARS-CoV-2 vaccines have been licensed and administered worldwide. These vaccines induce a targeted T-cell response against SARS-CoV-2. The cellular response after the third dose was strong and superior to that obtained with the second dose. COVID-19 multiple vaccines elicit a robust CD4+ and CD8+ T cell response after the short-term booster. While, the T-cell response induced by COVID-19 vaccines has been shown to decline within 6-12 months of vaccination. In addition, the long-term persistence of cellular immunity may protect against the development of severe disease. In addition, adoptive T-cell therapies have shown considerable potential in the development of COVID-19 traitement. These therapies involve the transfer of T cells with specific antiviral properties into patients to boost their immune response against SARS-CoV-2.

Background: Latent TB infection (LTBI) affects one fourth of the global population. Currently, there is an absence of an optimal strategy for distinguishing between active tuberculosis (aTB) and LTBI. While some researchers have explored cytokines other than interferon-gamma (IFN-γ) as biomarkers, results have shown significant variability in their ability to differentiate between these conditions. This meta-analysis aims to evaluate the performance of activation phenotype and chemokine markers in distinguishing between aTB and LTBI. Objectives: To assess the diagnostic accuracy of specific biomarkers (HLA-DR+ IFNγ+, CD38+ IFNγ+, MCP-1, and RANTES) in differentiating aTB from LTBI. Design: This study was conducted in accordance with the PRISMA guidelines for systematic reviews and meta-analyses of diagnostic studies. Data sources and methods: We conducted a comprehensive search of PubMed, Scopus, Sciences Direct, and Web of Science for primary studies published in English up to 2023. Studies were included if they reported sensitivity, specificity, diagnostic odds ratio (DOR), and area under the curve (AUC) for the biomarkers in question. We calculated pooled diagnostic sensitivity, specificity, DOR, and AUC, and used the summary receiver operating characteristic curve (SROC) to summarize the diagnostic performance of each biomarker. Results: Sixteen studies involving 1696 participants were included in the analysis. Among them, 925 individuals were diagnosed with aTB, while 771 were classified as having LTBI. The specificity, sensitivity, DOR, and AUC for CD38+ IFNγ+, HLA-DR+ IFNγ+, RANTES, and MCP-1 were (0.97 [95% CI: 0.72-1.00], 0.90 [95% CI: 0.75-0.96], 291.863, and 0.9432), (0.90 [95% CI: 0.70-0.97], 0.83 [95% CI: 0.63-0.94], 41.819, and 0.8598), (0.68 [95% CI: 0.55-0.79], 0.72 [95% CI: 0.56-0.84], 5.733, and 0.7979), and (0.63 [95% CI: 0.54-0.72], 0.63 [95% CI: 0.50-0.75], 2.892, and 0.7290) respectively. Conclusion: The findings indicate that CD38+ IFNγ+ and HLA-DR+ IFNγ+ demonstrated the highest diagnostic accuracy. Additional prospective research is necessary to identify the optimal combination of biomarkers to enhance diagnostic accuracy in clinical settings. Registration: This review has been registered on PROSPERO: (CRD42023472091). Available from: https://www.crd.york.ac.uk/prospero/#recordDetails [ABSTRACT FROM AUTHOR]

Background: In Morocco, latent tuberculosis infection (LTBI) is a public health concern affected by the country's location as transit area between sub-Saharan Africa with high TB burden to Europe. This study aimed to assess the influence of exposure intensity to Mycobacterium tuberculosis (Mtb), age, and Bacille Calmette–Guérin (BCG) vaccination on LTBI prevalence in Morocco. Methods: A cross-sectional study of 131 participants, including 98 non-exposed healthy volunteers (NEHV) and 33 healthcare workers exposed to active TB (exposed healthcare workers [EHCW]), was conducted. The Interferon-γ Release Assay (IGRA) was used to detect LTBI, and results were analyzed according to participants' age and BCG vaccination status. Results: EHCW showed a higher prevalence of LTBI than NEHV (36.7% vs. 57.6%) and of EHCW were positive for LTBI. In both groups, the mean age of those with LTBI was higher than those without. Furthermore, we showed within both groups, that LTBI prevalence was positively associated with subjects less covered by BCG vaccination in comparison with subjects likely totally covered by this vaccination (adjusted odds ratio [aOR], 2.783; 95% confidence intervals [CI], 1.180–6.57; P = 0, 01), (aOR, 6.717; 95% CI, 1.254–35.977; P = 0.02). Conclusion: Our results showed that in the Moroccan TB epidemic context, the prevalence of LTBI still lower among healthy adults general population than within EHCW. Furthermore, this LTBI showed to be positively impacted by age in the two condition of exposure. We also showed that BCG vaccination seems to affect the prevalence of LTBI within both high and low intensity of exposure to Mtb infection. [ABSTRACT FROM AUTHOR]

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Background: Allium sativum L. (A.S.) "garlic", one of the most interesting medicinal plants, has been suggested to contain compounds that could be beneficial in numerous pathological situations including cancer. In this work, we aimed to assess the immunomodulatory effect of A.S. preparation on human peripheral blood mononuclear cells from healthy individuals. Methods: Nontoxic doses of A.S. were identified using MTT assay. Effects on CD4+ or CD8+ T lymphocyte proliferation were studied using flow cytometry. The effect of A.S. on cytokine gene expression was studied using qRT-PCR. Finally, qualitative analysis of A.S. was performed by HPLC approach. Data were analyzed statistically by one-way ANOVA test. Results: The nontoxic doses of A.S. preparation did not affect neither spontaneous nor TCR-mediated CD4+ or CD8+ T lymphocyte proliferation. Interestingly, A.S. exhibited a statistically significant regulation of IL-17 gene expression, a cytokine involved in several inflammatory and autoimmune diseases. In contrast, the expression of IL-4, an anti-inflammatory cytokine, was unaffected. Qualitative analysis of A.S. ethanol preparation indicated the presence of three polyphenol bioactive compounds, which are catechin, vanillic acid and ferulic acid. Conclusion: The specific inhibition of the pro-inflammatory cytokine, IL-17 without affecting cell proliferation in human PBMCs by the Allium sativum L. preparation suggests a potential valuable effect of the compounds present in this plant for the treatment of inflammatory diseases and cancer, where IL-17 is highly expressed. The individual contribution of these three compounds to this global effect will be assessed. [ABSTRACT FROM AUTHOR]

Background: Capparis Spinosa L. is an aromatic plant growing wild in dry regions around the Mediterranean basin. Capparis Spinosa was shown to possess several properties such as antioxidant, antifungal, and anti-hepatotoxic actions. In this work, we aimed to evaluate immunomodulatory properties of Capparis Spinosa leaf extracts in vitro on human peripheral blood mononuclear cells (PBMCs) from healthy individuals. Results: Using MTT assay, we identified a range of Capparis Spinosa doses, which were not toxic. Unexpectedly, we found out that Capparis Spinosa aqueous fraction exhibited an increase in cell metabolic activity, even though similar doses did not affect cell proliferation as shown by CFSE. Interestingly, Capparis Spinosa aqueous fraction appeared to induce an overall anti-inflammatory response through significant inhibition of IL-17 and induction of IL-4 gene expression when PBMCs were treated with the non toxic doses of 100 and/or 500 µg/ml. Phytoscreening analysis of the used Capparis Spinosa preparations showed that these contain tannins; sterols, alkaloids; polyphenols and flavonoids. Surprisingly, quantification assays showed that our Capparis Spinosa preparation contains low amounts of polyphenols relative to Capparis Spinosa used in other studies. This Capparis Spinosa also appeared to act as a weaker scavenging free radical agent as evidenced by DPPH radical scavenging test. Finally, polyphenolic compounds including catechin, caffeic acid, syringic acid, rutin and ferulic acid were identified by HPLC, in the Capparis spinosa preparation. Conclusion: Altogether, these findings suggest that our Capparis Spinosa preparation contains interesting compounds, which could be used to suppress IL-17 and to enhance IL-4 gene expression in certain inflammatory situations. Other studies are underway in order to identify the compound(s) underlying this effect. [ABSTRACT FROM AUTHOR]

Mycobacterium tuberculosis (Mtb) infection remains one of the world's major causes of illness and mortality. A clear understanding of the host defense against Mtb is imperatively needed for the control of this epidemic. When tuberculosis (TB) infection occurs, a variety of pro and anti-inflammatory cytokines play a vital role in the pathogenesis of this disease. Interleukin-10 (IL-10) is one of the most important anti-inflammatory cytokines reported to suppress the protective immune response against tuberculosis. Aim. The aim of the present study was to evaluate the association of plasma IL-10 levels with various disease stages of TB and the possible effects of treatment on these levels. Materials and methods. A group of 30 patients with active pulmonary TB and a control group of 21 healthy individuals were enrolled in this study. The levels of IL-10 were measured before, during, and after treatment using commercially available enzyme-linked immune-sorbent assay (ELISA). Data were analyzed using GraphPad Prism version 5.0. Results. The results showed that the levels of IL-10 had significant differences between the TB and control groups (p<0.05). The patients with abnormal chest X-Ray findings had higher IL-10 levels when compared to patients with normal X-Rays (p=0.03). A subgroup of 18 patients were followed during the treatment and the mean plasma concentration of IL-10 in patients before therapy was higher than in patients at 3 months of therapy and in patients after 6 months of therapy (p=0.01). However, the IL-10 level remained significantly higher in patients at the end of treatment compared with controls. These findings could be used in follow-up as clinical biomarker of the success of tuberculosis therapy. [ABSTRACT FROM AUTHOR]

Background and aim. Tuberculosis (TB) remains a major public health issue in Romania. The aim of the present study was to evaluate the potential demographic, socioeconomic and behavioral risk factors for TB among hospitalized patients in Romania. Methods. This is a case-control study conducted between March 1st 2014 and March 30th 2015 at Leon Daniello Clinical Hospital of Pneumology, Cluj Napoca. A total of 150 TB patients defined as "cases" were matched for age, sex and county of residence to 150 controls selected from patients attending the same hospital with respiratory diseases other than TB. Data collection was obtained through patient interviews using a structured questionnaire. Factors potentially associated with TB infection were analyzed using univariate and multivariate logistic regression. Results. Factors independently associated with TB were illiteracy (OR=2.42, 95% CI 1.09-5.37), unemployment (OR=2.08, 95% CI 1.23-3.53), low household income (OR=4.12, 95% CI 2.53-6.71), smoking (more than 20 cigarettes per day) (OR=2.12, 95% CI 1.20-3.74), poor knowledge of TB (OR=3.46, 95% CI 1.97-6.07), presence of TB patient in household (OR=4.35, 95% CI 1.42-13.36), prior TB treatment (OR=2.2, 95% CI 1.93-2.5) and diabetes (OR=3.32, 95% CI 1.36-8.08). Conclusion. This study provided useful information that might help to develop and adapt effective policies for TB control in Romania. [ABSTRACT FROM AUTHOR]