CD4 and neoplasm: As a result, the LGG-MHI + US and LGG-MHS + US therapy significantly facilitated the proliferation and activation of tumor-infiltrating HTLs (CD3+CD4+) and CTLs (CD3+CD8+), suggesting that LGG combined with IDO reduction strategy in the presence of US therapeutic arrangement modality can effectively activate the immune system to kill the tumor cells (Fig. 7e and Supplementary Fig. 11).