CD4 and glioblastoma: The above data indicated that LRRC4 promoted chemotaxis and accumulation of CD4+CCR4+ T cells, the LRRC4 deletion in GBM cells was one cause of the accumulation of Ti-Treg cells (mainly neuropilin− Treg cells) in GBM, and re-expression of LRRC4 created a permissive intratumoral environment for Ti-Teff cell infiltration by inhibiting Ti-Treg cells.