Mechanism of action of VEGF in immune suppression: Difference between normal and tumor immunity

2021 Fiscal Year Final Research Report

• Project/Area Number: 20K16553
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 52010:General internal medicine-related
• Research Institution: Kagoshima University
• Principal Investigator: Takenouchi Kazunori 鹿児島大学, 医歯学域医学系, 助教 (30646758)
• Project Period (FY): 2020-04-01 – 2022-03-31
• Keywords: 血管内皮増殖因子 / 2次リンパ節 / 3次リンパ節 / VEGF121 / VEGF165

Outline of Final Research Achievements

In this study, we used mice overexpressing vascular endothelial growth factor (VEGF) in a B cell-specific manner and compared the histopathology within secondary lymph nodes of B cell-specific VEGF-expressing mice and wild-type mice in four groups after treatment with ovalbumin. The results showed that CD11b+Gr1+Myeloid-derived suppressor cells (MDSCs) within the lymph nodes tended to increase, but no significant differences were observed. We also observed proliferation of regulatory T cells, which were inferred to play a part in tumor evasion. We developed an ELISA system capable of measuring VEGF121,165 subtypes and found that VEGF in the blood was predominantly 121 rather than 165.

Free Research Field

臨床検査医学

Academic Significance and Societal Importance of the Research Achievements

VEGF が外来抗原に対して免疫抑制効果を示す機序を ovalbumin 皮下投与後のリンパ節を観察することにより探索した。VEGF の過剰が 制御性T細胞の増殖を示すことは、腫瘍の免疫逃避機構の解明の一端として VEGF が関与している可能性を示唆する内容であった。また、血中 VEGF の主たるサブタイプが 165 よりも 121 であることを発見したことは、癌治療における抗 VEGF 戦略において重要な発見だったと考える。