biostudies-literatureUnknown13Liu ZThyroid associated ophthalmopathy (TAO), characterized by T cell infiltration and orbital fibroblast activation, is an organ-specific autoimmune disease which is still short of effective and safety therapeutic drugs. The PD-1/PD-L1 pathway has been reported hindering the progression of Graves' disease to some extent by inhibiting T cell activity, and tumor therapy with a PD-1 inhibitor caused some adverse effects similar to the symptoms of TAO. These findings suggest that the PD-1/PD-L1 pathway may be associated with the pathogenesis of TAO. However, it remains unknown whether the PD-1/PD-L1 pathway is involved in orbital fibroblast activation. Here, we show that orbital fibroblasts from patients with TAO do not express PD-L1. Based on <i>in vitro</i> OF-T cell co-culture system, exogenousFrontiers in immunology849480https://www.ebi.ac.uk/biostudies/studies/S-EPMC9128409biostudies-literaturePD-L1 Inhibits T Cell-Induced Cytokines and Hyaluronan Expression <i>via</i> the CD40-CD40L Pathway in Orbital Fibroblasts From Patients With Thyroid Associated Ophthalmopathy.PMC9128409Liu YLi XLiu ZLiu MGong QGuan XShi AHao BYuan HBai XZhou XLiu FfalsePD-L1 Inhibits T Cell-Induced Cytokines and Hyaluronan Expression <i>via</i> the CD40-CD40L Pathway in Orbital Fibroblasts From Patients With Thyroid Associated Ophthalmopathy.Thyroid associated ophthalmopathy (TAO), characterized by T cell infiltration and orbital fibroblast activation, is an organ-specific autoimmune disease which is still short of effective and safety therapeutic drugs. The PD-1/PD-L1 pathway has been reported hindering the progression of Graves' disease to some extent by inhibiting T cell activity, and tumor therapy with a PD-1 inhibitor caused some adverse effects similar to the symptoms of TAO. These findings suggest that the PD-1/PD-L1 pathway may be associated with the pathogenesis of TAO. However, it remains unknown whether the PD-1/PD-L1 pathway is involved in orbital fibroblast activation. Here, we show that orbital fibroblasts from patients with TAO do not express PD-L1. Based on <i>in vitro</i> OF-T cell co-culture system, exogenous2022-01-01T00:00:00Z20222025-04-19T21:50:23.481Z2025-02-19T01:23:42.496ZS-EPMC91284093561970010.3389/fimmu.2022.849480