Publications by authors named "Sudhir Kumar Chauhan"

The immune checkpoint inhibitor ipilimumab provides long term survival in some metastatic melanoma patients, but the majority has no benefit, and may experience serious side effects. Here, we investigated the dynamics of plasma cytokine concentrations and their potential utility for predicting treatment response, adverse events and overall survival (OS) in patients with metastatic melanoma undergoing ipilimumab monotherapy. A cohort of 148 patients was examined, with plasma samples collected prior to treatment initiation and at the end of the first and second treatment cycles.

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Immunotherapies blocking the PD-1/PD-L1 checkpoint show some efficacy in metastatic breast cancer (mBC) but are often hindered by immunosuppressive mechanisms. Understanding these mechanisms is crucial for personalized treatments, with peripheral blood monitoring representing a practical alternative to repeated biopsies. In the present study, we performed a comprehensive mass cytometry analysis of peripheral blood immune cells in 104 patients with HER2 negative mBC and 20 healthy donors (HD).

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Background: Immune checkpoint inhibitors have shown minimal clinical activity in hormone receptor-positive metastatic breast cancer (HRmBC). Doxorubicin and low-dose cyclophosphamide are reported to induce immune responses and counter regulatory T cells (Tregs). Here, we report the efficacy and safety of combined programmed cell death protein-1/cytotoxic T-lymphocyte-associated protein 4 blockade concomitant with or after immunomodulatory chemotherapy for HRmBC.

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Article Synopsis
  • - The study investigates the characteristics and functions of regulatory T (Treg) CD4 cells in the human small intestine, which are crucial for managing immune responses to harmless substances.
  • - Researchers examined Treg and conventional CD4 T cells from various human gut samples, revealing that Treg cells can be categorized into two subsets based on the expression of the transcription factor Helios, each with distinct cytokine production and suppressive abilities.
  • - The findings indicate that Treg cells are rare in healthy intestines but significantly increase in individuals with active celiac disease, highlighting the potential role of these cells in intestinal immune regulation during pathological conditions.
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Immune checkpoint inhibitors have shown efficacy against metastatic triple-negative breast cancer (mTNBC) but only for PD-L1 disease. The randomized, placebo-controlled ALICE trial ( NCT03164993 , 24 May 2017) evaluated the addition of atezolizumab (anti-PD-L1) to immune-stimulating chemotherapy in mTNBC. Patients received pegylated liposomal doxorubicin (PLD) and low-dose cyclophosphamide in combination with atezolizumab (atezo-chemo; n = 40) or placebo (placebo-chemo; n = 28).

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Studies in mice and humans have shown that CD8 T cell immunosurveillance in non-lymphoid tissues is dominated by resident populations. Whether CD4 T cells use the same strategies to survey peripheral tissues is less clear. Here, examining the turnover of CD4 T cells in transplanted duodenum in humans, we demonstrate that the majority of CD4 T cells were still donor-derived one year after transplantation.

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Resident memory CD8 T (Trm) cells have been shown to provide effective protective responses in the small intestine (SI) in mice. A better understanding of the generation and persistence of SI CD8 Trm cells in humans may have implications for intestinal immune-mediated diseases and vaccine development. Analyzing normal and transplanted human SI, we demonstrated that the majority of SI CD8 T cells were bona fide CD8 Trm cells that survived for >1 yr in the graft.

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Systemic lupus erythematosus (SLE) patients exhibit immense heterogeneity which is challenging from the diagnostic perspective. Emerging high throughput sequencing technologies have been proved to be a useful platform to understand the complex and dynamic disease processes. SLE patients categorised based on autoantibody specificities are reported to have differential immuno-regulatory mechanisms.

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Background: Association of Mycobacterium avium subspecies paratuberculosis (MAP) and Crohn's disease (CD) has been controversial due to contradictory reports. Therefore, we determined the prevalence of MAP in patients with CD and intestinal tuberculosis (ITB) and its association with clinical course.

Methodology: Blood and intestinal biopsies were taken from 69 CD, 32 ITB patients and 41 patients with haemorrhoidal bleed who served as controls.

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Systemic lupus erythematosus (SLE) patients are generally presented with autoantibodies against either dsDNA or RNA-associated antigens (also known as extractable nuclear antigens, ENA) or both. However, the mechanisms and processes that lead to this distinctive autoantibody profile are not well understood. Defects in clearance mechanism i.

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Generation of autoantigens of nuclear origin, like dsDNA and extractable nuclear antigens (ENA) have largely been associated with dysregulated apoptosis and defective clearance of apoptotic debris in SLE. Heat shock protein (HSP) 27 has been reported to have anti-apoptotic properties hence it was of interest to study the expression of HSP27 and its regulatory molecule Brn3a and hsa-miR-939 in SLE patients with distinct autoantibodies specificities. SLE patients were categorized into three subsets based on their distinct sero-positivity for either anti-dsDNA antibody alone (anti-dsDNA(+) group) or anti-ENA antibody alone (anti-ENA(+) group) or both (anti-dsDNA(+) ENA(+) group).

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Background: Morbidity and mortality rates are very high in low birth weight (LBW) newborns because of their increased susceptibility to infections compared with normal birth weight (NBW) newborns. A case and control study was designed to identify the status of toll-like receptor-4 (TLR-4) signaling and maternally derived immunoglobulin-G (IgG) subclasses in term LBW newborns compared with NBW newborns.

Methods: To understand the basis of increased susceptibility to infections in LBW newborns, the levels of pro- and antiinflammatory cytokines interleukin-1β (IL-1β) and interleukin-10 (IL-10), respectively, released in response to lipopolysaccharide (LPS) stimulation of cord blood cells of LBW (n = 20) and NBW (n = 18) newborns, were quantified by enzyme-linked immunosorbent assay.

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Purpose: Systemic lupus erythematosus (SLE) patients have anti-nuclear autoantibodies directed against dsDNA and RNA-associated antigens (extractable nuclear antigens; ENA). In this study, we investigated the differences in microRNA (miRNA) expression and its biological implications in SLE patients with distinct autoantibody specificities.

Methods: The SLE patients were grouped into three subsets based on the type of autoantibodies present in their sera (anti- ENA+ group with autoantibodies against ENA alone; antidsDNA+ group having autoantibodies against dsDNA only, and anti-ENA+dsDNA+ group having autoantibodies to both dsDNA and ENA).

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Background: Morbidity and mortality rates of low birth weight (LBW) newborns at term are higher than rates in normal birth weight (NBW) newborns. LBW newborns are at greater risk to acquire recurrent bacterial and viral infections during their first few weeks of life possibly as an outcome of compromised innate immune functions. As adaptive immunity is in a naive state, increased risk of infection of LBW as compared to NBW newborns may reflect impairments in innate immunity.

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Purpose: Systemic lupus erythematosus (SLE) patients have a wide array of autoantibodies against nuclear antigens. The two predominant classes of these autoantibodies are directed either against dsDNA or RNA-associated antigens (extractable nuclear antigens; ENA). Nucleic-acid sensing Toll-like receptors (TLRs) that recognize dsDNA and RNA, have been well implicated in some murine models of SLE.

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