Rabies remains a major public health concern across many African and Asian countries, where accurate diagnosis is critical for effective epidemiological surveillance. The gold standard diagnostic methods rely heavily on fluorescence microscopy, necessitating skilled laboratory personnel for the accurate interpretation of results. Such expertise is often scarce, particularly in regions with low annual sample volumes. This paper presents an automated, AI-driven diagnostic system designed to address these challenges. We developed a robust pipeline utilizing fluorescent image analysis through transfer learning with four deep learning architectures: EfficientNetB0, EfficientNetB2, VGG16, and Vision Transformer (ViTB16). Three distinct data augmentation strategies were evaluated to enhance model generalization on a dataset of 155 microscopic images (123 positive and 32 negative). Our results demonstrate that TrivialAugmentWide was the most effective augmentation technique, as it preserved critical fluorescent patterns while improving model robustness. The EfficientNetB0 model, utilizing Geometric Color augmentation and selected through stratified 3fold cross-validation, achieved optimal classification performance on cropped images. Despite constraints posed by class imbalance and a limited dataset size, this work confirms the viability of deep learning for automating rabies diagnosis. The proposed method enables fast and reliable detection with significant potential for further optimization. An online tool was deployed to facilitate practical access, establishing a framework for future medical imaging applications. This research underscores the potential of optimized deep learning models to transform rabies diagnostics and improve public health outcomes.
IntroductionCervical tuberculous lymphadenitis (CTL) represents a localized manifestation of Mycobacterium tuberculosis infection in which immune responses are organized within lymphoid tissue. While cytotoxic lymphocyte responses contribute to antimycobacterial immunity, the cytokine networks coordinating these responses in human lymph node tuberculosis remain incompletely defined.MethodsWe performed integrated immune profiling of patients with CTL (n = 60) and non-tuberculous cervical lymphadenopathy (CNTL; n = 44). Immune−gene expression was quantified in peripheral blood and lymph node mononuclear cells by qPCR. Systems-level analyses including principal component and correlation-network approaches were used to define coordinated immune pathways. Serum IL−15 was measured by ELISA, and tissue localization of IL−15 and IL−15Rα was examined by immunohistochemistry.ResultsCTL was characterized by a structured cytotoxic immune program enriched for granulysin, granzyme B, perforin, IFN-γ, and CCL5. Network analysis identified IL-15 as a highly connected hub within this cytotoxic module in CTL. IL-15 transcripts were significantly elevated in both blood and lymph node compartments (p = 0.0003; p = 0.0007, respectively) and strongly correlated with cytotoxic effector genes. Circulating IL-15 concentrations were higher in CTL than CNTL (p < 0.0001) and increased with GeneXpert-defined bacillary burden (AUC 0.73). Immunohistochemistry demonstrated IL-15 and IL-15Rα expression within CD68+ macrophages localized to granulomatous regions, consistent with macrophage-mediated IL-15 trans-presentation within sites of infection.ConclusionsThese findings identify IL−15 as a potential central organizer of cytotoxic immune pathways in CTL and highlight IL−15–linked immune signatures as biologically informative features of CTL immunopathogenesis.
IntroductionTuberculosis (TB) remains the deadliest infectious disease in humans; however, a robust immune response can either protect against or control the infection. Household contacts of TB patients can remain uninfected for decades, while a quarter of the world's population that is latently infected can remain healthy for years. Characterization of the effectors of such an immune response would help in developing novel host-directed tools to better treat and/or prevent TB. IL-6 is a crucial cytokine that plays a central role in orchestrating a protective TB immune response; however, a delicate balance between its beneficial and detrimental effects must be maintained to effectively control the infection. Here, we aimed to characterize the cellular effectors that regulate IL-6 expression in mycobacteria-infected cells.MethodsWe used PI3K and AKT inhibitors, as well as FOXO3-specific siRNA, to modulate FOXO3 activity in BCG-infected macrophages and assessed the effect on IL-6 expression. Reporter gene assays were performed using four IL-6 promoter constructs (-600 bp, -900 bp, -1.5 kb, and -2 kb). In silico analysis was carried out using Genomatix software and the Eukaryotic Promoter Database to identify Forkhead binding motifs, followed by mutagenesis experiments to validate their function.ResultsThe PI3K/AKT/FOXO3 axis regulates IL-6 expression in human macrophages: FOXO3 activation (via PI3K or AKT inhibition) induced IL-6 expression, while FOXO3 silencing reduced IL-6 production in BCG-infected macrophages. FOXO3 positively regulated IL-6 promoter activity across all cloned fragments, with the strongest effect at -1.5 kb; extension to -2 kb modulated this FOXO3-mediated induction. In silico analysis identified three FOXO3-specific binding sites (-786, -1331, and -1631). Mutagenesis identified the motif at -1331 as the major positive regulator of IL-6 expression, while the motif at -1631 mediated the negative regulation exerted by the distal promoter fragment.DiscussionWe report for the first time that FOXO3 exerts both positive and negative regulation of IL-6 transcription, fine-tuning its expression in mycobacteria-infected macrophages. Together with our previous report on FOXO3-mediated suppression of IL-10, these results highlight the crucial role of FOXO3 in the TB immune response and support targeting the PI3K/Akt/FOXO3 axis as a host-directed approach to improve TB treatment and prevention.
Leishmania spp., the causative agents of leishmaniasis, pose significant global health threats, with visceral leishmaniasis being the most severe and fatal form. The increasing drug resistance in the treatment of leishmaniasis emphasizes the urgent need for novel therapeutic approaches. One promising strategy involves targeting essential cellular mechanisms such as nutrient acquisition, particularly iron, which is critical for energy metabolism and signal transduction. Leishmania spp. cannot synthesize heme de novo and rely on host-derived iron and heme for survival and pathogenicity. Gallium [Ga(III)] is an iron [Fe(III)]-mimetic molecule that has emerged as a promising antimicrobial agent, offering a novel approach to combat infections, mainly by replacing Fe(III) in redox enzymes thereby disrupting essential metabolic pathways and impairing microbial viability. In this study, the antiparasitic activity of Ga (III)-protoporphyrin IX (GaPPIX) was tested against Leishmania major and Leishmania infantum, both in promastigotes and intracellular amastigotes. Our results demonstrate that GaPPIX inhibits the viability of both species, specifically targeting the enzymatic activity of cytochrome c oxidase, with a higher sensitivity observed in L. major. The inhibitory effect is reversed by hemin, suggesting specificity for Leishmania heme-dependent cellular processes and a possible cytostatic action. Moreover, we found that GaPPIX can effectively synergize with miltefosine. This feature, coupled with its minimal toxicity toward human cells, makes GaPPIX a good candidate to be potentially developed as a novel anti-Leismania agent.IMPORTANCEThis study is significant as it addresses a critical challenge in leishmaniasis management, namely, the increasing incidence of drug resistance and toxicity, compounded by the scarcity of effective therapeutic options. We demonstrate that GaPPIX, a heme-mimetic compound, exhibits potent antiparasitic activity against both Leishmania major and Leishmania infantum, while displaying minimal cytotoxicity toward human cells, underscoring its potential as a safe and targeted therapeutic candidate. Importantly, the ability of GaPPIX to synergize with the first-line drug miltefosine highlights its translational relevance in combination therapies, which are essential for overcoming resistance and improving treatment efficacy. Collectively, these findings advance GaPPIX as a promising approach for the development of innovative therapeutics against a neglected but globally significant disease.
The number of individuals affected by dementia and cognitive decline is progressively increasing, becoming a serious global health challenge. Several investigations underline the role of nutrition and dietary habits as a preventive strategy. Recent studies suggest that dietary supplementation with polyphenols may constitute an efficient preventive strategy. Indeed, it is emerging that polyphenols exhibit a neuroprotective effect because of their pronounced antioxidant and anti-inflammatory activity. Notably, several studies underline the role of the gut microbiota in the metabolism of the polyphenols, producing bioactive molecules that are absorbed through the gastrointestinal tract. They may exhibit beneficial effects on the central nervous system. Moreover, dietary polyphenols modulate gut microbiota composition, demonstrating a reciprocal regulation between gut microbiota and polyphenol-induced effects on brain functions. Thus, polyphenols are proposed to have an important role on the gut-microbiota-brain axis regulation. The literature search for this narrative review was conducted across three electronic databases PubMed, Scopus, and Web of Science as well as the NIH ClinicalTrials.gov registry, covering the period from January 2000 to 10 February 2026. The following search terms were used: "polyphenols", "microbiota", "gut-brain axis", "dementia", "cognitive function", "polyphenols and cognitive dysfunction", and "polyphenols and microbiota". The study selection process was performed in two sequential stages: (i) screening of titles and abstracts, followed by (ii) full-text assessment for eligibility. Articles were included if they were peer-reviewed studies (in vitro, in vivo, or clinical trials), published in English, and addressed the effects of polyphenols on cognitive outcomes, gut microbiota composition, or the gut-microbiota-brain axis. Exclusion criteria included non-peer-reviewed sources, studies lacking relevant cognitive or microbiota-related endpoints, and publications not available in full.
