IDH1 and central nervous system cancer: While T cell dysfunction in glioblastoma has been extensively characterized, the role of innate lymphoid cells (ILCs)-critical regulators of tissue homeostasis and early immune responses- remains poorly understood.<h4>Methods</h4>We investigated how IDH1 mutations and their oncometabolite D-2-hydroxyglutarate (D-2HG) influence ILC subset distribution, immune checkpoint expression, and cytokine production in glioma patients, glioma-conditioned medium (GCM) models, and in vivo mouse experiments.