Bach2, also known as BTB Domain and CNC Homolog 2, is a transcription factor. It serves as a central regulator of immune cell differentiation and function, especially in T and B lymphocytes. Bach2 is involved in multiple pathways, such as controlling the balance between different CD4+ T cell subsets, Th2-related immune responses, and stem-like CD8+ T cell development [1,2,3,5]. Genetic models, like KO/CKO mouse models, are valuable for studying its functions.

In KO mouse models, Bach2 deficiency leads to spontaneous development of Th2 inflammation in the airway and gastrointestinal tract, indicating its role in regulating Th2 immune responses [3]. In CD8+ T cells, Bach2 deficiency impairs stem-like CD8+ T cell differentiation, revealing its importance in maintaining long-term immunity [2]. In T cells, deletion of Bach2 results in spontaneous development of type 2 airway inflammation, suggesting it suppresses Th2 cytokine production and differentiation [4]. Also, in B cells, Bach2 knockout affects class switch recombination and plasma cell differentiation [3,5].

In conclusion, Bach2 plays essential roles in immune cell differentiation and function, especially in maintaining the balance of different T and B cell subsets. KO/CKO mouse models have revealed its significance in Th2-related inflammatory diseases, stem-like CD8+ T cell-mediated immunity, and B cell-related humoral immunity. These findings provide insights into the mechanisms of immune-mediated diseases and potential therapeutic targets [1-3].

References:

1. Zwick, Daniel, Vo, Mai Tram, Shim, Young Jun, Reijonen, Helena, Do, Jeong-Su. 2024. BACH2: The Future of Induced T-Regulatory Cell Therapies. In Cells, 13, . doi:10.3390/cells13110891. https://pubmed.ncbi.nlm.nih.gov/38891024/

2. Yao, Chen, Lou, Guohua, Sun, Hong-Wei, Schwartzberg, Pamela L, Wu, Tuoqi. 2021. BACH2 enforces the transcriptional and epigenetic programs of stem-like CD8+ T cells. In Nature immunology, 22, 370-380. doi:10.1038/s41590-021-00868-7. https://pubmed.ncbi.nlm.nih.gov/33574619/

3. Liu, Guo, Liu, Feng. 2022. Bach2: A Key Regulator in Th2-Related Immune Cells and Th2 Immune Response. In Journal of immunology research, 2022, 2814510. doi:10.1155/2022/2814510. https://pubmed.ncbi.nlm.nih.gov/35313725/

4. Yamashita, Masakatsu, Kuwahara, Makoto. . The critical role of Bach2 in regulating type 2 chronic airway inflammation. In International immunology, 30, 397-402. doi:10.1093/intimm/dxy020. https://pubmed.ncbi.nlm.nih.gov/29529253/

5. Yang, Lingyi, Chen, Shuli, Zhao, Qiuyu, Sun, Ying, Nie, Hong. 2019. The Critical Role of Bach2 in Shaping the Balance between CD4+ T Cell Subsets in Immune-Mediated Diseases. In Mediators of inflammation, 2019, 2609737. doi:10.1155/2019/2609737. https://pubmed.ncbi.nlm.nih.gov/32082072/