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Parihar, S.

Publications and source records attributed to Parihar, S..

2 recordsLinked to original sources

The C3HeB/FeJ Kramnik mouse as a model to investigate the efficacy of therapeutic tuberculosis interventions

Tuberculosis (TB) remains a formidable global health challenge, classified as the leading infectious disease killer, driven by the increasing prevalence of multidrug-resistant Mycobacterium tuberculosis strains. This persistent threat not only overwhelms public health infrastructures but also deepens socio-economic inequalities worldwide, underscoring the urgent need for novel therapeutic strategies. The C3HeB/FeJ Kramnik mouse model, frequently used for its capacity to mimic human-like granulomatous lesions, has emerged as a pivotal tool in TB research. However, despite its advantages, the model has limitations, particularly in terms of macrophage pathology and restricted B-cell activity, which pose significant hurdles for translating preclinical findings into human applications. By developing models that better reflect human immune responses, the translation of findings into clinical applications may be improved, ultimately leading to more effective TB treatments and vaccines. This study aims to evaluate the Kramnik model by investigating the efficacy of a novel Pheroid(R) formulation containing traditional TB therapeutics in the C3HeB/FeJ Kramnik mouse model. The potential and limitations inherent to the Kramnik model are explored and the need for complementary genomic analyses, such as sequencing SP110 and SP140, to elucidate the susceptibility linked to the SST1 locus is illustrated. In addition, this article attempts to serve as a critical evaluation of the inherent limitations of current animal models like the Kramnik model, with the aim of paving the way for more accurate and reliable translational research in the fight against TB.

microbiology↗

Murine peritoneal macrophages undergo female-specific remodeling with aging

Aging is a complex process characterized by a progressive decline in physiological functions. Immune function is strongly influenced by biological sex, affecting both innate and adaptive responses. Here, we investigated the effects of age and sex on mouse peritoneal immune cells and identified macrophages as the top affected cell type. Macrophages, as central components of the innate immune system, play critical roles in homeostasis maintenance and infection response. We found that aging induces sex-specific remodeling of mouse peritoneal macrophage omic landscapes, which is accompanied by female-specific age-related functional remodeling (i.e. decreased phagocysis, increased glycolysis). We show that age-related changes in circulating estrogen levels likely drive aspects of female-specific macrophage age-related changes, specifically age-related phagocytosis decline. By leveraging our multi-omic dataset, we identify transcription factors whose female-specific age-regulation may drive female-specific age-related changes in peritoneal macrophage phenotypes. Interestingly, Irf2 downregulation was sufficient to recapitulate aspects of female peritoneal macrophage aging phenotypes, including increased glycolysis. Mechanistically, decreased Irf2 expression leads to decreased binding to its target genes, including Hk3, which encodes hexokinase (the rate-limiting enzyme of glycolysis). Our findings support the notion that aging leads to female-specific remodeling of mouse peritoneal macrophages through hormone-dependent and -independent mechanisms.

immunology↗