GDP-Driven purine metabolic rewiring promotes Th17-like polarization of CD4⁺ T cells and reveals a RANBP1-associated nucleo-metabolic program

Here, we asked whether extracellular GDP acts as an instructive purine signal and whether RANBP1, a regulator of Ran-GTP hydrolysis and nucleo-cytoplasmic trafficking, mediates the GDP-dependent phenotype. In primary human CD4⁺ T and Th17 cells, we integrated Raman imaging, RNA-seq, proteomics, purine metabolomics, Seahorse bioenergetics, lactate assays, flow cytometry, western blotting and RANBP1 perturbation.

GDP stimulation induced a coordinated nucleo-metabolic program rather than nonspecific activation. In CD4⁺ T cells, GDP remodeled nuclear biochemical composition, altered purine pools, enriched mitochondrial membrane and nucleotide-transporter pathways, and promoted a Th17-like signature marked by IL-23R, RORγt and IL-17A. Integrated RNA-seq/proteomic analysis revealed convergence on mitochondrial ATP/ADP transport, purine handling and immune differentiation, while western blotting showed modulation of PNP, LDHA and MCT1 together with lysine and histone-associated acetylation signals.