title: Characterization of γδ T Cells from Zebrafish Provides Insights into Their Important Role in Adaptive Humoral Immunity.
abstract: γδ T cells represent an evolutionarily primitive T cell subset characterized by distinct T cell receptors (TCRs) and innate and adaptive immune functions. However, the presence of this T cell subset in ancient vertebrates remains unclear. In this study, γδ T cells from a zebrafish (Danio rerio) model were subjected to molecular and cellular characterizations. The constant regions of zebrafish TCR-γ (DrTRGC) and δ (DrTRDC) were initially identified. Zebrafish γδ T cells accounted for 7.7-20.5% of the total lymphocytes in spleen, head kidney, peripheral blood, skin, gill, and intestine tissues. They possess typical morphological features of lymphocytes with a surface phenotype of γ+δ+CD4-CD8+. Zebrafish γδ T cells functionally showed a potent phagocytic ability to both soluble and particulate antigens. They can also act as an antigen-presenting cell to initiate antigen (KLH)-specific CD4+TKLHcell activation and to induce B cell proliferation and IgM production. Particularly, zebrafish γδ T cells also play a critical role in antigen-specific IgZ production in intestinal mucus. These findings demonstrated that γδ T cells had been originated as early as teleost fish, which providing valuable insights into the evolutionary history of T cell subset. It is anticipated that this study would be used as a guide to develop a zebrafish model for the cross-species investigation of γδ T cell biology.
authors.affiliation: College of Life Sciences, Zhejiang University, Hangzhou, China; Key Laboratory for Cell and Gene Engineering of Zhejiang Province, Hangzhou, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Wan
authors.affiliation: College of Life Sciences, Zhejiang University, Hangzhou, China; Key Laboratory for Cell and Gene Engineering of Zhejiang Province, Hangzhou, China.
authors.forename: Chong-Bin
authors.initials: CB
authors.lastname: Hu
authors.affiliation: College of Life Sciences, Zhejiang University, Hangzhou, China; Key Laboratory for Cell and Gene Engineering of Zhejiang Province, Hangzhou, China.
authors.forename: Jun-Xia
authors.initials: JX
authors.lastname: Ma
authors.affiliation: College of Life Sciences, Zhejiang University, Hangzhou, China; Key Laboratory for Cell and Gene Engineering of Zhejiang Province, Hangzhou, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Gao
authors.affiliation: College of Life Sciences, Zhejiang University, Hangzhou, China; Key Laboratory for Cell and Gene Engineering of Zhejiang Province, Hangzhou, China.
authors.forename: Li-Xin
authors.initials: LX
authors.lastname: Xiang
authors.affiliation: College of Life Sciences, Zhejiang University, Hangzhou, China; Key Laboratory for Cell and Gene Engineering of Zhejiang Province, Hangzhou, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
authors.forename: Jian-Zhong
authors.initials: JZ
authors.lastname: Shao
keywords: adaptive humoral immunity; antigen-presenting cells; identification; mucosal IgZ antibody; origin of T cell subset; zebrafish γδ T cells