Biochemistry, Genetics and Molecular Biology, Immunology and Microbiology, Molecular Biology, Virology
71
Scopus Publications
Scopus Publications
Depletion of myeloid cells in AG129 mice reduces the infection-mediated oxidative stress and restrains dengue virus-induced thymic atrophy B. Kusuma, Surender Rawat, Oindrila Saha, Sakshi Nimesh, Srikanth Sadhu, Amit Awasthi, Tushar K. Maiti, Arup Banerjee Cell Communication and Signaling, 2026 Infection-associated thymic atrophy is common and results in T-cell imbalance and immune dysfunction. Severe dengue, caused by infection with the dengue virus (DV), is associated with perturbation of T cell functions. However, it is unclear whether perturbation of T cell functions is linked to changes in thymic function during dengue infection. Herein, we employed a dengue virus serotype 2 (DV-2)-infected mouse model and Neonatal Thymic Organ Culture (NTOC) to study the impact of DV-2 infection on thymic function. Further, the contribution of infiltrating immune cells, especially myeloid cells, and reactive oxygen species (ROS) in the thymus on DV-2-induced thymic atrophy was studied by depleting Gr-1 + myeloid cells and quenching ROS in mice. We have demonstrated that DV-2 infection caused a massive thymic atrophy, dominated by a loss of CD4+ CD8+ double-positive (DP) thymocytes, reduction in naïve T cells in blood and spleen, a significant increase in the infiltration of myeloid cells, and a reactive oxygen species (ROS) burst in the thymus. Using Neonatal Thymic Organ Culture (NTOC), we confirmed that DV-2 infection alone cannot induce thymic atrophy. Further, we documented that depletion of Gr-1 + myeloid cells, or quenching of ROS using N-acetylcysteine (NAC) during DV-2 infection, partially protected thymic architecture. This protection of thymus function is also reflected in the thymic interstitial fluid proteome profile, where myeloid cells depletion or NAC treatment in DV-2-infected mice confirmed the reversal of protein expression associated with oxidative stress and neutrophil degranulation pathways within the thymus. Further, managing oxidative stress also influenced cytokine production by T cells in the spleen of infected mice. Thus, our study confirms that thymic atrophy does not depend on viremia level but on the interaction between immune cells and the virus, highlighting the contribution of infiltrating myeloid cells and, thus, ROS in DV-2-associated thymic atrophy. Dengue virus serotypes 2 & 3 (DV-2, DV-3) infection, but not serotype 1 (DV-1), leads to thymic atrophy in an experimental mouse model. Thymic atrophy depends not on the viremia level but on the specific host-virus interaction. Myeloid cells abundance and ROS level affect thymic output in severe dengue. The thymic interstitial fluid (TIF) protein profile reflects the atrophied. and non-involuted thymus status. Myeloid cells depletion or ROS quenching reverses the thymic atrophy-associated proteins in the TIF. ROS inhibition modulates the cytokine expression profile of T cells in the splenocytes of DV-2-infected mice.
Extracellular vesicles: the double-edged sword in viral infections Sharda Kumari, Arup Banerjee Mbio, 2026 Extracellular vesicles (EVs) are lipid-bound nanocarriers released by various eukaryotic cells and found in diverse bodily fluids. EVs have transitioned from being considered cellular waste disposers to significant players in intercellular communication and signaling. These EVs carry signature cargos of infected cells and thus can be helpful as biomarkers or prognostic markers for infectious diseases. Viruses can manipulate the EV biogenesis machinery in their own dissemination. EVs released from virus-infected cells can carry immune modulatory molecules, thus contributing to disease progression. This comprehensive review collates the information on the impact of EVs on viral infection and disease progression.
Neutrophil depletion at the early stage of Japanese encephalitis virus infection affects CD8+ T cell infiltration into the mouse brain and causes severe encephalitis Rohit Soni, Prasanjit Jena, B. Kusuma, Arup Banerjee Frontiers in Immunology, 2026 Neutrophils have been reported to have protective and detrimental functions in viral infections. However, the role of neutrophils remains unexplored in Japanese encephalitis virus (JEV) infection. In this study, we elucidated the dynamics of neutrophils and their influence on immune cell recruitment in subclinical and severe encephalitis in mouse models. Further, we depleted neutrophils from 3–4 week-old C57BL/6 mice using mAb1A8 (anti-Ly6G) antibody and studied their association with inflammation, viral replication, immune cell infiltration and disease outcome. We observed that an increase in JEV replication is associated with increased infiltration of neutrophils in the spleen and brain. Further studies confirmed that depletion of neutrophils at an early stage of JEV infection reduced CD8 abundance in the infected brain and accelerated death in mice. We also observed that inhibition of the CXCL12-CXCR4 signalling axis by antagonist AMD3100 reduced CD8 abundance in the brain and augmented inflammasome activation, leading to fatal encephalitis. Reduced CXCR4 levels in the spleen and blood of CD8+T cells correlated with enhanced Granzyme B level, indicating CD8 cells differentiated more into effector phenotypes in neutrophil-depleted mice. Furthermore, CD8 depletion delayed the death of mice infected with a sublethal strain compared to neutrophil-depleted mice, suggesting that neutrophils play a vital role in the early restriction of viral replication, whereas CD8 is essential later in clearing the virus. Taken together, our study sheds new light on the role of neutrophils in the pathogenic mechanisms of JEV encephalitis and highlights the importance of neutrophils and CD8 cells associated with disease outcomes.
Proteome Profiling in Cerebrospinal Fluid Reveals Increased Levels of Peroxiredoxin 2 Discriminating Japanese Encephalitis Virus and Scrub Typhus Infection Naina Soni, Rashmi Rameshwari, Ankit Biswas, Prasanjit Jena, Tushar K. Maiti, Bishal Gupta, Bhaswati Bandyopadhyay, Arup Banerjee Journal of Medical Virology, 2025 Japanese encephalitis virus (JEV) and scrub typhus (ST) are major etiological agents of acute encephalitis syndrome (AES) in India and South Asia. The pathophysiological changes at the molecular level caused by JEV and ST have yet to be studied in detail. The cerebrospinal fluid (CSF) proteomic landscape is a critical indicator of CNS pathology. Here, we conducted label‐free quantitative proteomics on CSF from AES patients (n = 15) to identify etiology‐specific differentially expressed proteins (DEPs) linked to encephalitis. The key DEPs were validated via ELISA in CSF (n = 49) and serum (n = 33). Our findings revealed 50 proteins exhibited differential expression across JEV and ST groups, with a notable subset of three proteins, PRDX2, KLK6, and TTR. PRDX2 and KLK6 were markedly elevated in JEV CSF (AUC: 0.8933 and 0.9689) but not in ST or non‐JEV AES, while TTR was reduced in JEV yet elevated in ST (AUC: 0.5619 vs. 0.8238). Further, PRDX2 upregulation was validated in JEV‐infected mouse brains and cortical neurons. Overexpression of PRDX2 in human neuroblastoma cells correlated with enhanced antiviral gene expression, p‐STAT1, p‐AKT (ser473), and viral replication. Thus, our comprehensive proteomic analysis of CSF identifies PRDX2 as an important circulatory protein, differentially expressed between JEV and ST, with high specificity and enhancing viral propagation, underscoring its role in viral propagation and pathogenesis.
Induction of PD-1 and CD44 in CD4+ T cells by circulatory extracellular vesicles from severe dengue patients drives endothelial damage via the NF-kB signaling pathway Sharda Kumari, Ankit Biswas, Tushar Kanti Maiti, Bhaswati Bandyopadhyay, Arup Banerjee Journal of Virology, 2025 Extracellular vesicles (EVs) emerged as critical contributors to the pathogenesis of vascular endothelial barrier dysfunction during the inflammatory response to infection. However, the contribution of circulating EVs to modifying endothelial function during dengue virus infection remains unclear. In this study, we showed that severe dengue patients’ plasma-derived EV (SD-EV) were found to carry elevated levels of different protein cargos, e.g., immunoregulatory proteins (PD-L1, CD44). Further, we demonstrated that SD-EV induces PD-1 and CD44 expression on CD4 + T cells. SD-EV-modulated CD4 + T (SD-EV-CD4) cells released secretome delayed endothelial cell (EC) migration, arrested them in the G1 phase, and augmented the expression of PD-L1 and ICAM-1 expression on EC through the Notch signaling pathway. Blocking SD-EV and CD4 + T-cell interaction through the PD-1/PD-L1 pathway partially rescued the CD4 + T cell’s effect on EC but did not alter ICAM-1 expression on EC. We observed that the ICAM-1 expression on EC and hyaluronic acid (HA) release from EC was mediated by CD44, which was elevated on SD-EV-modulated CD4 + T cells (SD-EV-CD4), indicating a permeability defect. Blocking of CD44 on SD-EV-CD4 significantly reduced ICAM-1 expression on EC. Further, depletion of specific cytokines, e.g., TNF-α and not IFN-γ from the SD-EV-CD4 secretome, reduced ICAM-1 expression, decreased transendothelial electrical resistance, and induced apoptosis on EC significantly. Treatment with NF-kB inhibitor before secretome addition to EC reduced ICAM-1 expression on EC. In conclusion, we provided evidence that SD-EV-CD4 carrying PD-1 and CD44, when interacting with EC, significantly affected endothelial cell properties and may be significant in dengue-mediated endothelial dysfunction. IMPORTANCE Extracellular vesicles (EVs) are small membrane vesicles secreted into biological fluids, including plasma from living cells, holding insights into pathological processes. Studying EVs under pathological conditions is extremely important as they play a selective role in intercellular communication and modulation of immune response under diverse pathological conditions. However, there is less clarity on how circulatory extracellular vesicles influence immune cells during dengue virus (DV) infection and impact pathogenesis. Our present study highlights the impact of severe dengue patients’ plasma-derived EV (SD-EV) on CD4 + T cells and together induce endothelial barrier dysfunction. We provided evidence that SD-EV induces PD-1 and CD44 on CD4 + T cells and, when interacting with endothelial cells (EC), drives endothelial damage through direct interaction or secretome and may be significant in dengue-mediated endothelial dysfunction.
Integrated proteomics and connectivity map-based analysis reveal compounds with a potential antiviral effect against Japanese encephalitis virus infection in a mouse model Rohit Soni, Naina Soni, Abhijit Paul, Aarti Tripathi, Samrat Chatterjee, Arup Banerjee FEBS Journal, 2025 Japanese encephalitis virus (JEV) is the leading causative agent of viral encephalitis in India and contributes to a significant disease burden in South Asian countries. However, no antiviral treatment is available against JEV‐induced encephalitis, highlighting the urgent need for novel therapeutic approaches. Repurposing or repositioning drugs was found to be more economical and practical in the current drug development scenario. The present study aimed to develop a host‐directed strategy through a computational drug repurposing approach. As part of the strategy, we first generated a dynamic signature of differentially expressed JEV infection‐associated proteins in mice brains through a semiquantitative proteomics approach. With the help of the Connectivity Map (CMap) analysis, we narrowed down the lists of drugs with a high negative CMap score (−70 or lower). Based on the CMap score, we chose the top three compounds (Tipifarnib, Ly303511 and MDL11939) with CMap scores of −91.83, −88.18 and −91.15, respectively. The antiviral potential of these three compounds was further compared in both JEV‐infected mouse neuroblastoma cells and C57BL/6 mice. Oral administration of Ly303511 and MDL11939, alone or in combination, showed improved outcomes (e.g. delayed death, increased survival, and less viral load than Tipifarnib alone or combined). The JEV‐infected mice survived upon drug treatment, effectively reducing viral load and reversing the antiviral signature. Our results highlight Ly303511 and MDL11939 as promising host‐targeted inhibitors of JEV infection and pathogenesis. Moreover, our results favor the combination of Ly303511 and MDL11939 therapy to improve clinical symptoms and reduce JEV‐induced damage, thus warranting inclusion in clinical studies.
Phenotypic alteration by dengue virus serotype 2 delays neutrophil apoptosis and stimulates the release of prosurvival secretome with immunomodulatory functions Surender Rawat, Shubham Kumar, Shweta Duggal, Arup Banerjee Journal of Leukocyte Biology, 2024 Neutrophils are the most abundant granuloytes, are phenotypically heterogeneous, and exert detrimental or protective roles during antiviral response. Dengue virus has been reported to activate neutrophils. However, the effect of the dengue virus on the neutrophil phenotypes, survival, and release of inflammatory secretome is yet to be understood. Herein, we investigated the effect of dengue virus serotype 2 (DV-2) on effector functions of naïve neutrophils and studied the impact of its secretome on different immune cells. We found that DV-2 activates purified human neutrophils and causes a significant shift toward the CD16bright/CD62Ldim subtype in a multiplicity of infection and time-dependent manner. These phenotypically altered neutrophils show delayed apoptosis through nuclear factor κB and PI3K pathways and have decreased phagocytic capacity. Treatment of neutrophils with myeloperoxidase and PAD4 inhibitor before DV-2 incubation significantly reduced DV-2–induced double-stranded DNA release, suggesting that myeloperoxidase and PAD4 were involved at early stages for the neutrophil activation and double-stranded DNA release. We also report that DV-2–stimulated neutrophil secretome had a significant effect on viral infection, platelet activation, and naïve neutrophil survival via binding of tumor necrosis factor α to tumor necrosis factor receptor 1/2 receptors. Furthermore, incubation of endothelial cells with the DV-2–stimulated neutrophil secretome potentially inhibits proliferation and wound healing capacity and induces endothelial cell death, which can contribute to endothelial barrier dysfunction. In conclusion, the neutrophil–DV-2 interaction modulates the phenotype of neutrophils and the release of prosurvival and antiviral secretome that may act as a double-edged sword during dengue pathogenesis.
Methotrimeprazine is a neuroprotective antiviral in JEV infection via adaptive ER stress and autophagy Surendra K Prajapat, Laxmi Mishra, Sakshi Khera, Shadrack D Owusu, Kriti Ahuja, Puja Sharma, Eira Choudhary, Simran Chhabra, Niraj Kumar, Rajan Singh, Prem S Kaushal, Dinesh Mahajan, Arup Banerjee, Rajender K Motiani, Sudhanshu Vrati, Manjula Kalia EMBO Molecular Medicine, 2024 Japanese encephalitis virus (JEV) pathogenesis is driven by a combination of neuronal death and neuroinflammation. We tested 42 FDA-approved drugs that were shown to induce autophagy for antiviral effects. Four drugs were tested in the JE mouse model based on in vitro protective effects on neuronal cell death, inhibition of viral replication, and anti-inflammatory effects. The antipsychotic phenothiazines Methotrimeprazine (MTP) & Trifluoperazine showed a significant survival benefit with reduced virus titers in the brain, prevention of BBB breach, and inhibition of neuroinflammation. Both drugs were potent mTOR-independent autophagy flux inducers. MTP inhibited SERCA channel functioning, and induced an adaptive ER stress response in diverse cell types. Pharmacological rescue of ER stress blocked autophagy and antiviral effect. MTP did not alter translation of viral RNA, but exerted autophagy-dependent antiviral effect by inhibiting JEV replication complexes. Drug-induced autophagy resulted in reduced NLRP3 protein levels, and attenuation of inflammatory cytokine/chemokine release from infected microglial cells. Our study suggests that MTP exerts a combined antiviral and anti-inflammatory effect in JEV infection, and has therapeutic potential for JE treatment.
Dengue virus infection in mice induces bone marrow myeloid cell differentiation and generates Ly6Glow immature neutrophils with modulated functions Shweta Duggal, Surender Rawat, Gazala Siddqui, Preeti Vishwakarma, Sweety Samal, Arup Banerjee, Sudhanshu Vrati Journal of Leukocyte Biology, 2024 While neutrophil activation during dengue virus infection is known, the effect of dengue virus infection on neutrophil biogenesis has not been studied. We demonstrate that dengue virus serotype 2 induces the differentiation of mice progenitor cells ex vivo toward the CD11b+Ly6C+Ly6G+ granulocyte population. We further observed an expansion of CD11b+Ly6CintLy6Glow myeloid cells in the bone marrow of dengue virus serotype 2–infected AG129 mice with low CXCR2 expression, implying an immature population. Additionally, dengue virus serotype 2 alone could induce the differentiation of promyelocyte cell line HL-60 into neutrophil-like cells, as evidenced by increased expression of CD10, CD66b, CD16, CD11b, and CD62L, corroborating the preferential shift toward neutrophil differentiation by dengue virus serotype 2 in the mouse model of dengue infection. The functional analysis showed that dengue virus serotype 2–induced neutrophil-like cells exhibited reduced phagocytic activity and enhanced NETosis, as evidenced by the increased production of myeloperoxidase, citrullinated histones, extracellular DNA, and superoxide. These neutrophil-like cells lose their ability to proliferate irreversibly and undergo arrest in the G0 to G1 phase of the cell cycle. Further studies show that myeloperoxidase-mediated signaling operating through the reactive oxygen species axis may be involved in dengue virus serotype 2–induced proliferation and differentiation of bone marrow cells as ABAH, a myeloperoxidase inhibitor, limits cell proliferation in vitro and ex vivo, affects the cell cycle, and reduces reactive oxygen species production. Additionally, myeloperoxidase inhibitor reduced NETosis and vascular leakage in dengue virus serotype 2–infected AG129 mice. Our study thus provides evidence that dengue virus serotype 2 can accelerate the differentiation of bone marrow progenitor cells into neutrophils through myeloperoxidase and modulate their functions.
Hepatitis B virus genotype D infection among antenatal patients attending a maternity hospital in Calcutta, India: Assessment of infectivity status Southeast Asian Journal of Tropical Medicine and Public Health, 2005
