Publications by authors named "Priyoshi Lahiri"

Digital dermatitis (DD) is a skin disease in cattle characterized by painful inflammatory ulcerative lesions in the feet, mostly associated with local colonization by spp., including . The reason why most DD lesions remain actively inflamed and progress to chronic conditions despite antibiotic treatment remains unknown.

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Article Synopsis
  • - Calves are very vulnerable to gastrointestinal infections, especially from pathogens like C. parvum, which can lead to severe diarrhea, poor growth, or even death. Consequently, studying the interaction between the pathogen and the gut microbiota is essential for developing better treatment strategies.
  • - In a study with neonatal calves challenged by C. parvum, significant symptoms like fever and diarrhea were observed five days after exposure, along with signs of severe intestinal inflammation and an unbalanced gut microbiome characterized by harmful bacteria and toxins.
  • - Supplementing calves with high-quality colostrum showed some promise in easing clinical symptoms and improving gut immune responses, making the gut environment resemble that of healthy calves, although its overall effectiveness in reducing diarrhea was limited.
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Cathelicidin peptides secreted by leukocytes and epithelial cells are microbicidal but also regulate pathogen sensing via toll-like receptors (TLRs) in the colon by mechanisms that are not fully understood. Herein, analyses with the attaching/effacing pathogen Citrobacter rodentium model of colitis in cathelicidin-deficient (Camp-/-) mice, and colonic epithelia demonstrate that cathelicidins prevent apoptosis by sustaining post-transcriptional synthesis of a TLR adapter, toll-interacting protein (TOLLIP). Cathelicidins induced phosphorylation-activation of epidermal growth factor receptor (EGFR)-kinase, which phosphorylated-inactivated miRNA-activating enzyme Argonaute 2 (AGO2), thus reducing availability of the TOLLIP repressor miRNA-31.

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Cathelicidins are small, cationic peptides produced by macrophages with protective effects against infection although their involvement in phagocytosis is not fully understood. This study demonstrates that fewer macrophages were recruited in mice genetically deficient in cathelicidin (Camp) during acute Escherichia coli-induced peritonitis and those macrophages had impaired phagocytosis. These defects seem due to endogenous functions of murine cathelicidin (CRAMP) as phagocytosis was not improved by synthetic human cathelicidin (LL-37) in a murine phagocytic cell line.

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Digital dermatitis (DD) causes lameness in cattle with substantial negative impact on sustainability and animal welfare. Although several species of bacteria have been isolated from various DD stages, their individual or synergistic roles in the initiation or development of lesions remain largely unknown. The objective of this study was to compare effects of the three most common species isolated from DD lesions in cattle (), both as individual and as mixed inoculations, in a murine abscess model.

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Cell types differentiated from induced pluripotent stem cells (iPSCs) are frequently arrested in their development program, more closely resembling a fetal rather than an adult phenotype, potentially limiting their utility for downstream clinical applications. The fetal phenotype of iPSC-derived dendritic cells (ipDCs) is evidenced by their low expression of MHC class II and costimulatory molecules, impaired secretion of IL-12, and poor responsiveness to conventional maturation stimuli, undermining their use for applications such as immune-oncology. Given that iPSCs display an epigenetic memory of the cell type from which they were originally derived, we investigated the feasibility of reprogramming adult DCs to pluripotency to determine the impact on the phenotype and function of ipDCs differentiated from them.

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Mycobacterium avium subsp. paratuberculosis (MAP) causes chronic diarrheic intestinal infections in domestic and wild ruminants (paratuberculosis or Johne's disease) for which there is no effective treatment. Critical in the pathogenesis of MAP infection is the invasion and survival into macrophages, immune cells with ability to carry on phagocytosis of microbes.

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Digital dermatitis (DD), a common ulcerative disease of the bovine foot causing lameness and reducing productivity and animal welfare, is associated with infection by spirochete Treponema bacteria. Topical tetracycline, the most common treatment, has inconsistent cure rates; therefore, new therapeutic options are needed. We compared effects of topical oxytetracycline and vitamin D on innate immunity in DD-affected skin.

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Digital dermatitis (DD) commonly associated with spp. infection is a prevalent infectious bovine foot disease characterized by ulcerative and necrotic lesions. Lesions associated with DD are often classified using the M-stage scoring system, with M0 indicating healthy heel skin and M4 indicating chronic lesions.

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Few topics in regenerative medicine have inspired such impassioned debate as the immunogenicity of cell types and tissues differentiated from pluripotent stem cells. While early predictions suggested that tissues derived from allogeneic sources may evade immune surveillance altogether, the pendulum has since swung to the opposite extreme, with reports that the ectopic expression of a few developmental antigens may prompt rejection, even of tissues differentiated from autologous cell lines. Here we review the evidence on which these contradictory claims are based in order to reach an objective assessment of the likely magnitude of the immunological challenges ahead.

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