Publications by authors named "Surya P Pandey"

Gasdermins are canonically associated with plasma membrane pore formation and lytic cell death. Gasdermin C (GsdmC), predominantly expressed in intestinal epithelial cells (IECs), seems to operate independently of these canonical roles. Here, we show that activated GsdmC is increased in response to type 2 immunity in the gut, driven by Cathepsin S (CTSS)-mediated cleavage.

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Exercise improves immune checkpoint inhibitor (ICI) efficacy in cancers such as melanoma; however, the mechanisms through which exercise mediates this antitumor effect remain obscure. Here, we identify that the gut microbiota plays a critical role in how exercise improves ICI efficacy in preclinical melanoma. Our study demonstrates that exercise stimulates microbial one-carbon metabolism, increasing levels of the metabolite formate, which subsequently enhances cytotoxic CD8 T cell (Tc1)-mediated ICI efficacy.

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Unlabelled: Understanding the initiation of T-helper (Th)-2 immunity is crucial for addressing allergic diseases that have been linked to the commensal microbiota. However, Th2 responses are notably absent from known host-microbiota intestinal immune circuits. Notably, the commensal protist induces a transient innate ILC2 circuit rather than a chronic Th2 circuit.

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Article Synopsis
  • The parasite Leishmania causes Leishmaniasis by residing in macrophage vacuoles and manipulating host cell signaling pathways.
  • The study finds that LmjMAPK4, a specific mitogen-activated protein kinase, is overexpressed in virulent L. major and affects macrophage responses by selectively interacting with certain MAPKs.
  • Targeting LmjMAPK4 with a specific inhibitor can restore protective immune functions in infected mice, highlighting its potential as a drug target for treating Leishmaniasis.
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Residing obligatorily as amastigotes within the mammalian macrophages, the parasite Leishmania donovani inflicts the potentially fatal, globally re-emerging disease visceral leishmaniasis (VL) by altering intracellular signaling through kinases and phosphatases. Because the phosphatases that modulate the VL outcome in humans remained unknown, we screened a human phosphatase siRNA-library for anti-leishmanial functions in THP-1, a human macrophage-like cell line. Of the 251 phosphatases, the screen identified the Ca-activated K-channel-associated phosphatase myotubularin-related protein-6 (MTMR6) as the only phosphatase whose silencing reduced parasite load and IL-10 production in human macrophages.

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The protozoan parasite Leishmania donovani resides within mammalian macrophages and alters its antigen-presenting functions to negatively regulate host-protective T cell responses. This negative regulation of human T cell responses in vitro is attributed to myotubularin-related protein-6 (MTMR6), an ion channel-associated phosphatase. As mouse and human MTMR6 share homology, we studied whether MTMR6 silencing by lentivirally expressed MTMR6shRNA (Lv-MTMR6shRNA) reduced Leishmania growth in macrophages and whether MTMR6 silencing in Leishmania-susceptible BALB/c mice reduced the infection and reinstated host-protective T cell functions.

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Systemic Lupus Erythematosus (SLE) or Lupus is a multifactorial autoimmune disease of multiorgan malfunctioning of extremely heterogeneous and unclear etiology that affects multiple organs and physiological systems. Some racial groups and women of childbearing age are more susceptible to SLE pathogenesis. Impressive progress has been made towards a better understanding of different immune components contributing to SLE pathogenesis.

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While the seasonal testicular cycle has been well studied regarding internal components, no attention has been given to the testicular capsule (tunica albuginea and tunica serosa). This study elucidated the structure-function modulations of intra-testicular functions by its capsule in the finch red munia (Amandava amandava) during the annual testicular cycle. The birds were studied during breeding (preparatory and breeding) and nonbreeding (regressive and quiescent) reproductive phases using hematoxylin-eosin and acridine orange-ethidium bromide capsule staining, hormonal ELISA (LH and testosterone) and immunohistochemical expression of neuropeptides (GnRH, GnIH) and androgen receptor (AR).

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Leishmania infection of macrophages results in altered Ras isoforms expression and Toll-like receptor-2 (TLR2) expression and functions. Therefore, we examined whether TLR2 would selectively alter Ras isoforms' expression in macrophages. We observed that TLR2 ligands- Pam3CSK4, peptidoglycan (PGN), and FSL- selectively modulated the expression of Ras isoforms in BALB/c-derived elicited macrophages.

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Loss of oral tolerance (LOT) to gluten, driven by dendritic cell (DC) priming of gluten-specific T helper 1 (Th1) cell immune responses, is a hallmark of celiac disease (CeD) and can be triggered by enteric viral infections. Whether certain commensals can moderate virus-mediated LOT remains elusive. Here, using a mouse model of virus-mediated LOT, we discovered that the gut-colonizing protist Tritrichomonas (T.

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The use of probiotics by cancer patients is increasing, including among those undergoing immune checkpoint inhibitor (ICI) treatment. Here, we elucidate a critical microbial-host crosstalk between probiotic-released aryl hydrocarbon receptor (AhR) agonist indole-3-aldehyde (I3A) and CD8 T cells within the tumor microenvironment that potently enhances antitumor immunity and facilitates ICI in preclinical melanoma. Our study reveals that probiotic Lactobacillus reuteri (Lr) translocates to, colonizes, and persists within melanoma, where via its released dietary tryptophan catabolite I3A, it locally promotes interferon-γ-producing CD8 T cells, thereby bolstering ICI.

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The triggers that drive interferon-γ (IFNγ)-producing CD8 T cell (Tc1 cell)-mediated autoimmune hepatitis (AIH) remain obscure. Here, we show that lack of hematopoietic Tet methylcytosine dioxygenase 2 (Tet2), an epigenetic regulator associated with autoimmunity, results in the development of microbiota-dependent AIH-like pathology, accompanied by hepatic enrichment of aryl hydrocarbon receptor (AhR) ligand-producing pathobionts and rampant Tc1 cell immunity. We report that AIH-like disease development is dependent on both IFNγ and AhR signaling, as blocking either reverts ongoing AIH-like pathology.

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Multiple pathogen-associated molecular patterns (PAMPs) on a pathogen's surface imply their simultaneous recognition by the host cell membrane-located multiple PAMP-specific Toll-like receptors (TLRs). The TLRs on endosomes recognize internalized pathogen-derived nucleic acids and trigger anti-pathogen immune responses aimed at eliminating the intracellular pathogen. Whether the TLRs influence each other's expression and effector responses-termed TLR interdependency-remains unknown.

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One major determinant of systemic immunity during homeostasis and in certain complex multifactorial diseases (e.g. cancer and autoimmune conditions), is the gut microbiota.

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IRF5 polymorphisms are associated with multiple immune-mediated diseases, including ulcerative colitis. IRF5 contributions are attributed to its role in myeloid lineages. How T cell-intrinsic IRF5 contributes to inflammatory outcomes is not well understood.

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causes cutaneous leishmaniasis. An antileishmanial vaccine for humans is unavailable. In this study, we report development of two attenuated strains-5ASKH-HP and LV39-HP-by continuous culture (high passage) of the corresponding virulent strains (low passage).

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IRF5 genetic variants leading to decreased IRF5 expression reduce risk for ulcerative colitis. However, how IRF5 regulates intestinal inflammation and contributes to the balance between defenses against intestinal pathogens and inflammation in vivo, and the cells mediating this balance, are not known. We found that deleting IRF5 in mice led to reduced intestinal inflammation in the T cell transfer colitis model, with reduced Th1 and Th17, and increased Th2 cytokines.

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Background: Blood biomarkers are a cost-effective and valid method to diagnose ischemic stroke and differentiate its subtypes in countries with poor resources.

Objective: To perform a systematic review of published literature evaluating the diagnostic utility of blood-based biomarkers to diagnose and differentiate the etiology of ischemic stroke.

Methods: A comprehensive literature search was carried out till December 2017 in major scientific and medical databases including PubMed, Cochrane, OVID and Google Scholar.

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Toll-like receptors (TLRs) recognize the pathogen-associated molecular patterns (PAMPs) and induce host-protective immune response. The role of the profilin-recognizing TLR11/TLR12 in Leishmania infection is unknown. Herein, we report that TLR11/ TLR12 expression increases in virulent L.

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The effect of two thyroid disrupting pesticides (TDPs) mancozeb (MCZ) and imidacloprid (IMI) on the hypothalamic-pituitary-gonadal/testicular (HPG) axis of a seasonally breeding bird, Amandava amandava has been evaluated. Male birds (n=8/group) were exposed to each of the pesticide (0.25% LD of respective pesticide) as well as to their two equimixture doses (0.

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Non-target organisms, including human and wildlife, are susceptible to deleterious effects of pesticide mixtures in their environment. Present study demonstrated the disruption of the hypothalamic-pituitary-thyroid (HPT) axis in a seasonally breeding wildlife bird Amandava amandava on co-exposure to dithiocarbamate mancozeb/MCZ and neonicotinoid imidacloprid/IMI, at concentrations even lower than respective environmentally realistic exposure level of each of the pesticide. Adult male birds (n=8/group) were exposed individually to 0.

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The exposure effects of two endocrine disrupting pesticides (EDPs), mancozeb/MCZ and imidacloprid/IMI of the group dithiocarbamate and neonicotinoid respectively, on reproductive behaviors and secondary sexual characters have been studied in a seasonally breeding wildlife bird, red munia (Amandava amandava). Adult male birds were exposed to both the pesticides individually (0.25% LD of each) as well as co-exposed (MIX-I: 0.

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Bacopa monnieri extract has been implicated in the recovery of memory impairments due to various neurological disorders in animal models and humans. However, the precise molecular mechanism of the role of CDRI-08, a well characterized fraction of Bacopa monnieri extract, in recovery of the diabetes mellitus-induced memory impairments is not known. Here, we demonstrate that DM2 mice treated orally with lower dose of CDRI-08 (50- or 100 mg/kg BW) is able to significantly enhance spatial memory in STZ-DM2 mice and this is correlated with a significant decline in oxidative stress and up regulation of the AMPA receptor GluR2 subunit gene expression in the hippocampus.

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The parasite Leishmania major counteractively modulates TLR2 and TLR9 expression and their functions. Although TLR1, TLR3, TLR4, and TLR7 are also implicated in Leishmania infection, whether their expression was altered in TLR2 or TLR9 deficiency remained unknown. Therefore, we examined TLR1, TLR3, TLR4 and TLR7 expression in L.

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