T helper 17 in the formation of intracranial aneurysm

Abstract

Objective To detect the level of interleukln 17 （IL-17） and transcription factor of orphan nuclear hormone receptor-γt （RORγt） in the intracranial aneurysm of humans and rats, and confirm whether T helper 17 （ Th17 ） takes part in the formation of intracranial aneurysm. Methods The models of intracranial aneurysm induced by nephrotic hypertension in Sprague-Dawley （ SD ） rats were established. Eight aneurysmal changes were found in the junction of the anterior cerebral （ACA） and the olfactort artery （OA） of rats, and immunohistochemistry was used to detect the expression level of IL-17 and RORTt, as well as 15 patients with intracranial aneurysms. Results Both IL-17 and RORγt were obviously expressed in the brain of rats with intracranial aneurysms as compared with the opposite control group. The percentage of IL-17 positive cells was associated with the percentage of RORγt positive cells （r = 0. 917 ,P 〈 0. 01 ）. No intraeranial aneurysm was induced in control group. Both IL-17 and RORγt in patients with intracranial aneurysms were obviously expressed, as well as LCA and CD4. The percentage of IL-17 positive cells was associated with the percentage of RORγt positive cells （r =0. 903 ,P 〈0. 01 ）. There was no expression of IL-17 and RORγt in the superficial temporal artery of normal controls. Conclusion Obvious expression of IL-17 and RORγt in the intracranial aneurysm of humans and rats may imply that Th17 response involves in the formation of intracranial aneurysm. Key words: Intracranial aneurysm; T cell; IL-17