Folate Receptor Beta Performs an Immune Checkpoint Function in Activated Macrophages

The study explores the role of folate receptor β (FRβ) in immune regulation, particularly in macrophages and its impact on tumor growth and immune response. Using FRβ knockout mice, researchers observed autoimmune symptoms such as alopecia and dermatitis, alongside slower tumor growth due to increased inflammatory macrophage activity and altered T cell populations. High FRβ expression in human cancers correlated with poorer survival, suggesting its role in tumor progression. The study concludes that FRβ is crucial for macrophage-mediated immunosuppression and impacts T cell activation, highlighting its potential as a target in cancer immunotherapy. Additionally, about 20% of FRβ KO mice exhibited spontaneous hair loss, indicating a possible link between FRβ and hair health.