Search results for "Immune system"

Induced arginine transport via cationic amino acid transporter-1 is necessary for human T-cell proliferation

2015

Availability of the semiessential amino acid arginine is fundamental for the efficient function of human T lymphocytes. Tumor-associated arginine deprivation, mainly induced by myeloid-derived suppressor cells, is a central mechanism of tumor immune escape from T-cell-mediated antitumor immune responses. We thus assumed that transmembranous transport of arginine must be crucial for T-cell function and studied which transporters are responsible for arginine influx into primary human T lymphocytes. Here, we show that activation via CD3 and CD28 induces arginine transport into primary human T cells. Both naive and memory CD4(+) T cells as well as CD8(+) T cells specifically upregulated the hum…

Genetics and Pathogenetic Role of Inflammasomes in Philadelphia Negative Chronic Myeloproliferative Neoplasms: A Narrative Review

2021

The last decade has been very important for the quantity of preclinical information obtained regarding chronic myeloproliferative neoplasms (MPNs) and the following will be dedicated to the translational implications of the new biological acquisitions. The overcoming of the mechanistic model of clonal evolution and the entry of chronic inflammation and dysimmunity into the new model are the elements on which to base a part of future therapeutic strategies. The innate immune system plays a major role in this context. Protagonists of the initiation and regulation of many pathological aspects, from cytokine storms to fibrosis, the NLRP3 and AIM2 inflammasomes guide and condition the natural hi…

A Weaning Reaction to Microbiota Is Required for Resistance to Immunopathologies in the Adult.

2019

International audience; Microbes colonize all body surfaces at birth and participate in the development of the immune system. In newborn mammals, the intestinal microbiota is first shaped by the dietary and immunological components of milk and then changes upon the introduction of solid food during weaning. Here, we explored the reactivity of the mouse intestinal immune system during the first weeks after birth and into adulthood. At weaning, the intestinal microbiota induced a vigorous immune response—a “weaning reaction”—that was programmed in time. Inhibition of the weaning reaction led to pathological imprinting and increased susceptibility to colitis, allergic inflammation, and cancer …

Component-Resolved Diagnosis of American Cockroach (Periplaneta americana) Allergy in Patients From Different Geographical Areas

2021

Background:Manifestation of respiratory allergy to American cockroach (Periplaneta americana) is prominent in the subtropical and tropical areas. However, co-existing perennial indoor inhalant allergies frequently compromise clinical diagnosis of cockroach allergy, and the analysis of sensitization pattern is limited by the lack ofPeriplanetaallergens widely available for component-resolved diagnostics (CRD).Objective:To evaluate a collection of previously described recombinantPeriplanetaallergens for CRD in cockroach allergy.Methods:A panel of nine recombinantPeriplaneta allergens (Per a 1–5, 7–10) was generated, purified, and subjected to physicochemical characterization by applying circu…

Activation of Mevalonate Pathway Via LKB1 is Essential for Stability of Treg Cells

2019

Summary: The function of regulatory T (Treg) cells depends on lipid oxidation. However, the molecular mechanism by which Treg cells maintain lipid metabolism after activation remains elusive. Liver kinase B1 (LKB1) acts as a coordinator by linking cellular metabolism to substrate AMP-activated protein kinase (AMPK). We show that deletion of LKB1 in Treg cells exhibited reduced suppressive activity and developed fatal autoimmune inflammation. Mechanistically, LKB1 induced activation of the mevalonate pathway by upregulating mevalonate genes, which was essential for Treg cell functional competency and stability by inducing Treg cell proliferation and suppressing interferon-gamma and interleuk…

Intra-tumour heterogeneity of diffuse large B-cell lymphoma involves the induction of diversified stroma-tumour interfaces

2020

Abstract Background Intra-tumour heterogeneity in lymphoid malignancies encompasses selection of genetic events and epigenetic regulation of transcriptional programs. Clonal-related neoplastic cell populations are unsteadily subjected to immune editing and metabolic adaptations within different tissue microenvironments. How tissue-specific mesenchymal cells impact on the diversification of aggressive lymphoma clones is still unknown. Methods Combining in situ quantitative immunophenotypical analyses and RNA sequencing we investigated the intra-tumour heterogeneity and the specific mesenchymal modifications that are associated with A20 diffuse large B-cell lymphoma (DLBCL) cells seeding of d…

2016

Atopic dermatitis (AD) is a widespread inflammatory skin disease with an early onset, characterized by pruritus, eczematous lesions and skin dryness. This chronic relapsing disease is believed to be primarily a result of a defective epidermal barrier function associated with genetic susceptibility, immune hyper-responsiveness of the skin and environmental factors. Although the important role of abnormal immune reactivity in the pathogenesis of AD is widely accepted, the role of regulatory T cells (Tregs) remains elusive. We found that the Treg population is expanded in a mouse model of AD, i.e. mice topically treated with vitamin D3 (VitD). Moreover, mice with AD-like symptoms exhibit incre…

Increased tumor vascularization is associated with the amount of immune competent PD‑1 positive cells in testicular germ cell tumors

2018

Testicular germ cell cancer in a metastatic state is curable with a cisplatin‑based first line chemotherapy. However, 10‑15% of these patients are resistant to first line chemotherapy and are thus left with only palliative options. Immunotherapies and inhibition of angiogenesis used in multiple types of cancer; however, the molecular context of angiogenesis and immune checkpoints in the development and progression of testicular cancers is still unknown. Therefore, the present study performed tissue micro array based analysis of 84 patients with immunohistochemistry of programmed cell death protein 1 (PD‑1), programmed cell death ligand 1 (PD‑L1) and vascular endothelial growth factor recept…

Immune-Endocrine Interactions in the Fish Gonad during Infection: An Open Door to Vertical Transmission

2018

The interaction between the immune and endocrine systems has long been recognized in vertebrates. In fish, it is known that the prevalence and intensity of such infections are higher in males than in females and probably related to sex steroid hormone levels. In addition, the immune response in the fish gonad tissues is specifically regulated to prevent infertility. This condition is used by some pathogens to colonize the fish gonad, evade the systemic immune response, and so spread to the progeny. This review brings up to date our knowledge concerning fish gonad immunity and its regulation, immune-endocrine interactions, and how some pathogens use this tissue to spread to the progeny throu…

Protein corona–mediated targeting of nanocarriers to B cells allows redirection of allergic immune responses

2018

Background Nanoparticle (NP)–based vaccines are attractive immunotherapy tools because of their capability to codeliver antigen and adjuvant to antigen-presenting cells. Their cellular distribution and serum protein interaction ("protein corona") after systemic administration and their effect on the functional properties of NPs is poorly understood. Objectives We analyzed the relevance of the protein corona on cell type–selective uptake of dextran-coated NPs and determined the outcome of vaccination with NPs that codeliver antigen and adjuvant in disease models of allergy. Methods The role of protein corona constituents for cellular binding/uptake of dextran-coated ferrous nanoparticles (DE…