CD4 and glioblastoma: A study of tumor infiltrating immune cell profiles revealed the lymphocyte proportion in GBM, primarily including CD4+ T (0.5%±0.7%) and CD8+ T cells (0.6% ± 0.7%), and smaller numbers of CD4-CD8-T cells (0.2% ± 0.4%), Tregs (0.1% ± 0.2%), B lymphocytes (0.1% ± 0.2%), and NK cells (0.05% ± 0.05 %) 128.