Regulatory T cells (Treg) are important in the development of immune tolerance under normal physiological conditions. However, in pathological situations such as cancer, Treg increases have been correlated with bad prognoses. Treg depletion can be achieved in vitro under several stimuli, including the activation of the purinergic P2X7 receptor. Our aim was to determine whether polymyxin B (PMB), which is a positive modulator of this receptor, could affect mice Treg depletion by ATP and related compounds. For that purpose, we evaluated by flow cytometry changes in Treg populations under several treatments with PMB and/or purinergic agonists and antagonists. We found that both ATP and NAD induce a dose-dependent decrease on the Treg CD4+ CD25+ population. PMB not only potentiated the effect of exogenous ATP and NAD, but also decreased the CD4+ CD25+ population when it was applied alone. While ATP mediated effects are related to the P2X7 receptor, PMB effects appear to be related to another mechanism. We conclude that PMB positively modulates the depletion of the CD4+ CD25+ population of Treg. Therefore PMB could constitute a non-canonical drug with potential use on Treg depletion and cancer treatment.
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http://dx.doi.org/10.1016/j.imbio.2011.10.006 | DOI Listing |
Sci Rep
January 2025
Department of Dermatology, Gunma University Graduate School of Medicine, 3-39-22, Showa, Maebashi, Gunma, 371-8511, Japan.
Systemic sclerosis (SSc) is an idiopathic systemic connective tissue disorder characterized by fibrosis of the skin and internal organs, with growing interest in the imbalance between Th17 cells and regulatory T cells (Tregs) in the disease's pathogenesis. Heligmosomoides polygyrus (Hp), a natural intestinal parasite of mice, is known to induce Tregs in the host. We aimed to investigate the effects of Hp-induced Tregs on bleomycin-induced dermal fibrosis and clarify the role of the Th17/Treg balance in SSc fibrosis.
View Article and Find Full Text PDFJ Immunother Cancer
January 2025
Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri, USA
Background: Treatment with immunotherapy can elicit varying responses across cancer types, and the mechanistic underpinnings that contribute to response vrsus progression remain poorly understood. However, to date there are few preclinical models that accurately represent these disparate disease scenarios.
Methods: Using combinatorial radio-immunotherapy consisting of PD-1 blockade, IL2Rβγ biased signaling, and OX40 agonism we were able to generate preclinical tumor models with conflicting responses, where head and neck squamous cell carcinoma (HNSCC) models respond and pancreatic ductal adenocarcinoma (PDAC) progresses.
Int J Mol Sci
December 2024
Department of Biomedical and Pharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul 02446, Republic of Korea.
The amount of sphingosine 1-phosphate (S1P) found in the synovial tissue of individuals with rheumatoid arthritis is five times greater than that in those with osteoarthritis. Our study aims to determine whether inhibiting S1P can mitigate collagen-induced rheumatoid arthritis (CIA) by using an S1P antagonist, JTE-013, alongside DBA-1J wild-type (WT) and knock-out (KO) mice. CIA causes increases in arthritis scores, foot swelling, synovial hyperplasia, pannus formation, proteoglycan depletion, cartilage damage, and bone erosion, but these effects are markedly reduced when JTE-013 is administered to WT mice.
View Article and Find Full Text PDFInt Immunopharmacol
January 2025
Department of Oral Biology, School and Hospital of Stomatology, Jilin University, Changchun, China; Key Laboratory of Tooth Development and Bone Remodeling of Jilin Province, School and Hospital of Stomatology, Jilin University, Changchun, China. Electronic address:
J Immunother Cancer
January 2025
Center for Translational Research in Hematologic Malignancies, Houston Methodist Neal Cancer Center, Houston Methodist Research Institute, Houston, Texas, USA
Background: Cancer immunotherapy using immune checkpoint blockade (ICB) has revolutionized cancer treatment. However, patients with multiple myeloma (MM) rarely respond to ICB. Accumulating evidence indicates that the complicated tumor microenvironment (TME) significantly impacts the efficacy of ICB therapy.
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