biostudies-literatureUnknown7(2)Li ZTumor necrosis factor receptor superfamily member 4 (TNFRSF4), also known as OX40, plays a crucial role in the regulation of T-cell immune responses under normal physiological conditions. Abnormal expression of OX40 and its cognate ligand OX40L (TNFSF4) have been associated with various autoimmune diseases, indicating that blocking the OX40/OX40L pathway could be a promising strategy for the treatment of a broad range of T cell-mediated autoimmune diseases. Here, we screened and characterized a fully human anti-OX40 antibody (JY007) from a naïve human scFv phage library. JY007 has an affinity constant of 7.71 nmol/L and effectively inhibited the OX40-OX40L interaction at both molecular and cellular levels, with IC₅₀ values of 1.088 and 10.12 nmol/L, respectively. Furthermore, JYMarine life science & technology328-339https://www.ebi.ac.uk/biostudies/studies/S-EPMC12102438biostudies-literatureA novel anti-OX40 human monoclonal antibody that blocks OX40/OX40L signaling and depletes OX40<sup>+</sup> T cells.PMC12102438Li ZLiu LIqbal MOChen JGu YZhang YChen XWang YZhang BWu XfalseA novel anti-OX40 human monoclonal antibody that blocks OX40/OX40L signaling and depletes OX40<sup>+</sup> T cells.Tumor necrosis factor receptor superfamily member 4 (TNFRSF4), also known as OX40, plays a crucial role in the regulation of T-cell immune responses under normal physiological conditions. Abnormal expression of OX40 and its cognate ligand OX40L (TNFSF4) have been associated with various autoimmune diseases, indicating that blocking the OX40/OX40L pathway could be a promising strategy for the treatment of a broad range of T cell-mediated autoimmune diseases. Here, we screened and characterized a fully human anti-OX40 antibody (JY007) from a naïve human scFv phage library. JY007 has an affinity constant of 7.71 nmol/L and effectively inhibited the OX40-OX40L interaction at both molecular and cellular levels, with IC₅₀ values of 1.088 and 10.12 nmol/L, respectively. Furthermore, JY2025-01-01T00:00:00Z2025 May2026-06-01T11:36:50.151Z2026-04-08T11:56:52.956ZS-EPMC121024384041725710.1007/s42995-025-00284-y