T Lymphocyte Infiltration in Association with IDO1 Expression in Resected Lung Adenocarcinoma and Normal Adjacent Lung Tissues

• Published in: BioMed research international 2022-02, Vol.2022, p.2381018-9
• Main Authors: Zhao, Xiaoling, Li, Yaran, Yang, Xu, Zhang, Xiaochong, Xie, Jing, Li, Shaoteng, Liu, Hongzhen, Guo, Jun, He, Lili, Chen, Wei, Liu, Dengxiang
• Format: Article
• Language: English
• Subjects: Adenocarcinoma; Adenocarcinoma of Lung - immunology; Adenocarcinoma of Lung - pathology; Adenocarcinoma of Lung - surgery; Adult; Aged; Antibodies; Apoptosis; Biomarkers; Catabolism; CD3 antigen; CD4 antigen; CD4-Positive T-Lymphocytes - immunology; CD8 antigen; Chemotherapy; Development and progression; Female; Gene expression; Genetic aspects; Health aspects; Histology; Humans; Immunoblotting; Immunohistochemistry; Immunosurveillance; Immunotherapy; Indoleamine-Pyrrole 2,3,-Dioxygenase - immunology; Infiltration; Kinases; Lung cancer; Lungs; Lymphocytes; Lymphocytes T; Male; Metastases; Middle Aged; mRNA; Mutation; Natural killer cells; Neoplasm Staging; Oxidoreductases; Proteins; RNA, Messenger - metabolism; Statistical analysis; T cells; Thoracic surgery; Tissues; Tryptophan; Tryptophan 2,3-dioxygenase; Tryptophan metabolism; Tumor cells; Tumors
• ISSN: 2314-6133; 2314-6141
• DOI: 10.1155/2022/2381018

Background. Indoleamine 2,3-dioxygenase 1 (IDO1) catalyzes the first step of tryptophan catabolism in the kynurenine (Kyn) pathway. IDO1 downregulates natural killer cell receptors, and by mechanism, tumor cells escape immune surveillance. Methods. IDO1 protein and mRNA were assessed by immunohistochemistry, immunoblotting, and PCR in the 68 resected lung adenocarcinomas at stages I–III as well as adjacent normal lung tissues. Infiltration of CD3, CD8, and CD4 lymphocytes in the tumor and adjacent normal lung tissues was assessed by immunohistochemical staining. Results. IDO1 protein and mRNA were detected in various stages of lung adenocarcinoma with highest expression at stage III. In contrast, biomarkers of T cell subset, CD3, CD4, and CD8, were highly expressed in the normal lung tissues and stage I adenocarcinoma tissues but significantly reduced in the stage II and III tumor tissues. Conclusions. The current study demonstrated that the higher level of IDO1 expression in the lung adenocarcinoma was, the less infiltration of T lymphocytes was found in the tumors. Findings of this study indicated that IDO1 may contribute to the reduction of T lymphocyte infiltration into the lung adenocarcinoma.