Search results for "immunology and allergy"

Donor interleukin-22 and host type I interferon signaling pathway participate in intestinal graft-versus-host disease via STAT1 activation and CXCL10.

2014

Acute graft-versus-host disease (aGVHD) remains a major complication following allogeneic hematopoietic cell transplantation, limiting the success of this therapy. We previously reported that interleukin-22 (IL-22) participates to aGVHD development, but the underlying mechanisms of its contribution remain poorly understood. In this study, we analyzed the mechanism of the pathological function of IL-22 in intestinal aGVHD. Ex-vivo colon culture experiments indicated that IL-22 was able to induce Th1-like inflammation via signal transducer and activator of transcription factor-1 (STAT1) and CXCL10 induction in the presence of type I interferon (IFN). To evaluate a potential synergy between IL…

Autoimmune diseases and 8.1 ancestral haplotype: an update

2018

The aim of the present review is to provide an update of the current research into the pathogenesis of autoimmune diseases associated with 8.1 ancestral haplotype. This is a common Caucasoid haplotype carried by most people who type for HLA-B8, DR3. Numerous genetic studies reported that individuals with certain HLA alleles have a higher risk of specific autoimmune disorders than those without these alleles. However, much remains to be learned about the heritability of autoimmune conditions. Recently, progress and advances in the field of genome-wide-association studies have revolutionized the capacity to perform large, economically feasible, and statistically robust analyses of HLA within …

Frontline Science: Mast cells regulate neutrophil homeostasis by influencing macrophage clearance activity

2019

Abstract The receptor tyrosine kinase cKit and its ligand stem cell factor are essential for mast cells (MC) development and survival. Strains with mutations affecting the Kit gene display a profound MC deficiency in all tissues and have been extensively used to investigate the role of MC in both physiologic and pathologic conditions. However, these mice present a variety of abnormalities in other immune cell populations that can affect the interpretation of MC-related responses. C57BL/6 KitW-sh are characterized by an aberrant extramedullary myelopoiesis and systemic neutrophilia. MC deficiency in KitW-sh mice can be selectively repaired by engraftment with in vitro-differentiated MC to va…

Group 3 Innate Lymphoid Cells Program a Distinct Subset of IL-22BP-Producing Dendritic Cells Demarcating Solitary Intestinal Lymphoid Tissues.

2019

Solitary intestinal lymphoid tissues such as cryptopatches (CPs) and isolated lymphoid follicles (ILFs) constitute steady-state activation hubs containing group 3 innate lymphoid cells (ILC3) that continuously produce interleukin (IL)-22. The outer surface of CPs and ILFs is demarcated by a poorly characterized population of CD11c+ cells. Using genome-wide single-cell transcriptional profiling of intestinal mononuclear phagocytes and multidimensional flow cytometry, we found that CP- and ILF-associated CD11c+ cells were a transcriptionally distinct subset of intestinal cDCs, which we term CIA-DCs. CIA-DCs required programming by CP- and ILF-resident CCR6+ ILC3 via lymphotoxin-β receptor sig…

Antigen-dependent competition shapes the local repertoire of tissue-resident memory CD8+ T cells.

2016

Muschaweckh et al. show that antigen presentation in the skin regulates the generation of tissue-resident memory T (TRM) cells by orchestrating local competition of antiviral CD8+ T cells, revealing a mechanism to fine-tune the repertoire of regional pools of TRM cells.

Treating severe asthma:Targeting the IL‐5 pathway

2021

Abstract Severe asthma is a heterogeneous disease with different phenotypes based on clinical, functional or inflammatory parameters. In particular, the eosinophilic phenotype is associated with type 2 inflammation and increased levels of interleukin (IL)‐4, IL‐5 and IL‐13). Monoclonal antibodies that target the eosinophilic inflammatory pathways (IL‐5R and IL‐5), namely mepolizumab, reslizumab, and benralizumab, are effective and safe for severe eosinophilic asthma. Eosinophils threshold represents the most indicative biomarker for response to treatment with all three monoclonal antibodies. Improvement in asthma symptoms scores, lung function, the number of exacerbations, history of late‐o…

IL-17 polarization of MAIT cells is derived from the activation of two different pathways

2017

MAIT cells are expanded in salivary glands of patients with Sjogren's syndrome and are IL-17 polarized. IL-7 and IL-23 induce IL-17 production activating two different pathways: IL-7 stimulation induces in fact a significant STAT3 and HIF1alpha upregulation, conversely, IL-23 stimulation significantly induces RORc overexpression in MAIT cells of patients with Sjogren's syndrome.

Regulatory T cells and vaccine effectiveness in older adults. Challenges and prospects

2021

Since the discovery of lymphocytes with immunosuppressive activity, increasing interest has arisen in their possible influence on the immune response induced by vaccines. Regulatory T cells (Tregs) are essential for maintaining peripheral tolerance, preventing autoimmune diseases, and limiting chronic inflammatory diseases. However, they also limit beneficial immune responses by suppressing anti-infectious and anti-tumor immunity. Mounting evidence suggests that Tregs are involved, at least in part, in the low effectiveness of immunization against various diseases where it has been difficult to obtain protective vaccines. Interestingly, increased activity of Tregs is associated with aging, …

HSP60 is a ubiquitous player in the physiological and pathogenic interactions between the chaperoning and the immune systems

2017

HSP60 participates in many interactions between the system integrated by all chaperones and closely associated molecules (chaperoning system or CS) and the immune system (IS). These interactions occur constantly to maintain normal cell physiology but, occasionally, they are perturbed and become mediators of pathologic events that may lead to disease. This switch to pathology may be initiated by various factors, genetic or acquired, which cause qualitative and/or quantitative modifications of HSP60, or immune crossreactivity between the human and microbial chaperonin orthologs, or a break in the balance between the pro- and anti-inflammatory actions of the chaperonin. Thus, autoimmune and ch…

2017

ABSTRACTTissue immunosurveillance is an important mechanism to prevent cancer. Skin treatment with the carcinogen 7,12-dimethylbenz(a)anthracene (DMBA), followed by the tumor promoter 12-O-tetra-decanoyl-phorbol-13-acetate (TPA), is an established murine model for squamous cell carcinoma (SCC). However, the innate immunological events occurring during the initiation of chemical carcinogenesis with DMBA remain elusive. Here, we discovered that natural killer (NK) cells and Langerhans cells (LC) cooperate to impair this oncogenic process in murine skin. The depletion of NK cells or LC caused an accumulation of DNA-damaged, natural killer group 2D-ligand (NKG2D-L) expressing keratinocytes and …