A preliminary study on transforming growth factor⁃β combined with CD3+, CD4+, CD8+ T cells in detecting the immune microenvironment of glioblastoma

Abstract

Objective To analyze the expression of immune cells and immunosuppressive factors in the immune microenvironment of glioblastoma. Methods A total of 30 glioma specimens, all of which were glioblastoma (IDH⁃wildtype), were surgically removed and completely preserved in the First Affiliated Hospital of Ji'nan University and Guangdong Sanjiu Brain Hospital from November 2020 to April 2021. T lymphocytes (CD3+ T cells, CD4+ T cells, CD8+ T cells), suppressive immune cells [FoxP3+ regulatory T cell (Treg)], immunosuppressive factors [transforming growth factor⁃β (TGF⁃β)], immunosuppressive factors [programmed cell death protein ligand 1 (PDL1)] in the immune microenvironment of glioblastoma were detected by immunohistochemistry. Results The proportion of CD4+ T cells in glioblastoma was very low. CD3+ T cells accounted for more than 3% in 15 cases (50%), and CD8+ T cells were similar to CD3+ T cells. Few FoxP3+ Treg cells were detected in only 2 cases (6.67%). The cytoplasm of 24 cases (80%) of glioblastoma showed strong positive expression of TGF⁃β, and its expression was correlated with the distribution of CD3+ T cells. No CD3+ T cells were found in the areas with high expression of TGF⁃β, and CD3+ T cells were widely distributed in the areas with low expression of TGF⁃β. PDL1 expression was non⁃detected. Conclusions TGF⁃β protein was highly expressed in glioblastoma, and future drugs or immunotherapies designed to target TGF⁃β may contribute to the clinical treatment of glioblastoma.

Keywords

• glioblastoma
• tumor microenvironment
• transforming growth factor beta
• t⁃lymphocytes
• immunohistochemistry