Molecular basis for the thymic microenvironments that characterize the immune system

2014 Fiscal Year Final Research Report

• Project/Area Number: 23249025
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Immunology
• Research Institution: The University of Tokushima
• Principal Investigator: TAKAHAMA Yousuke 徳島大学, 疾患プロテオゲノム研究センター, 教授 (20183858)
• Co-Investigator(Kenkyū-buntansha): TAKADA Kensuke 徳島大学, 疾患プロテオゲノム研究センター, 講師 (40570073)
• Co-Investigator(Renkei-kenkyūsha): OHIGASHI Izumi 徳島大学, 疾患プロテオゲノム研究センター, 特任助教 (00596588)
• Project Period (FY): 2011-04-01 – 2015-03-31
• Keywords: 獲得免疫 / Tリンパ球 / 胸腺 / レパトア形成 / 胸腺上皮細胞

Outline of Final Research Achievements

Towards understanding of molecular mechanisms that govern repertoire formation of T lymphocytes in the thymic microenvironments, this study identified and characterized (1) amino acid motifs for MHC-I-associated self-peptides that induce positive selection of CD8 T cells and (2) CCL21+ subpopulation of medullary thymic epithelial cells and beta5t+ thymic nurse cells. This study also indicated that (3) complete thymectomy in early human infancy reduces the number of circulating T cells and T-cell-mediated immune responses, suggesting that the thymus should be at least partially preserved during surgery in early infancy to maintain protective immunity. Furthermore, we found that (4) the number of Hassall's corpuscles and CCL21 expression in the thymic medulla was significantly elevated in the thymuses of myasthenia gravis patients with thymic hyperplasia, suggesting that the altered mTEC differentiation is associated with thymic hyperplasia and the onset of myasthenia gravis.

Free Research Field

免疫学