title: Identification and characterization of CD4(+)AT2(+) T lymphocyte population in human thoracic aortic aneurysm.
abstract: Thoracic aortic aneurysm (TAA) is progressive fatal aortic pathological dilation. However, the underlying molecular mechanisms are still largely unknown. Evidences suggest that endothelial cells and renin-angiotensin system may participate in the pathogenesis of TAA. This study aimed to investigate whether angiotensin II type 2 receptor (AT2) positive cells are involved in TAA formation. The mRNA level of AT2 is dramatically elevated in TAA compared with in controls. CD4(+)AT2(+) cells increased in both aortic wall and circulation of TAA patients. The levels of IL-1β and IL-17B in CD4(+)AT2(+) cells were lower than those in CD4(+)AT2(-) cells. When compared with endothelial cells (ECs) cultured alone, CD4(+)AT2(+) cells showed an inhibitory effect on proliferation and MMP2 expression in ECs, but CD4(+)AT2(-) cells promoted proliferation and MMP2 expression in ECs. Both CD4(+)AT2(+) and CD4(+)AT2(-) cells suppressed apoptosis of ECs. In conclusion, we have identified a novel population of CD4(+)AT2(+) T lymphocytes that show protective effect in TAA through inhibition of growth, apoptosis, and MMP2 expression in ECs.
authors.affiliation: Department of Cardiovascular Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China ; Department of Renji-Med X Clinical Stem Cell Research Center, Renji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China.
authors.forename: Chenxi
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Renji-Med X Clinical Stem Cell Research Center, Renji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Wu
authors.affiliation: Department of Renji-Med X Clinical Stem Cell Research Center, Renji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China.
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Hu
authors.affiliation: Department of Cardiovascular Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China.
authors.forename: Ritai
authors.initials: R
authors.lastname: Huang
authors.affiliation: Department of Cardiovascular Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Lian
authors.affiliation: Department of Cardiovascular Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China.
authors.forename: Weijun
authors.initials: W
authors.lastname: Wang
authors.affiliation: Department of Cardiovascular Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Feng
authors.affiliation: Department of Cardiovascular Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Xie
authors.affiliation: Department of Cardiovascular Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China.
authors.forename: Zhenlei
authors.initials: Z
authors.lastname: Hu
authors.affiliation: Department of Cardiovascular Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China.
authors.forename: Xinming
authors.initials: X
authors.lastname: Zhai
authors.affiliation: Department of Cardiovascular Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China.
authors.forename: Jidong
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Cardiovascular Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China.
authors.forename: Jianmin
authors.initials: J
authors.lastname: Gu
authors.affiliation: Department of Renji-Med X Clinical Stem Cell Research Center, Renji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of Cardiovascular Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China ; Department of Renji-Med X Clinical Stem Cell Research Center, Renji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Cardiovascular Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China.
authors.forename: Song
authors.initials: S
authors.lastname: Xue
keywords: Angiotensin II type 2 receptor; endothelial cell; inflammation; matrix metalloprotease 2; thoracic aortic aneurysm