CCR4 and glioblastoma: The exosomes derived from LRRC4 overexpression GBM cells caused significant chemotaxis and expansion of CD4+CCR4+ T cells (Figures 2C,D), inhibited the proportion of Ti-Treg cells (Figure 2E), mainly the CD4+CD25+CD127−neuropilin− Ti-iTreg cells (Figure 2F), and promoted Ti-Teff cell expansion (Figure 2G), consistent with the results obtained using the conditioned medium.