Generation of functional mammary glands by mammary stem cells

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K10552
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: General surgery
• Research Institution: The University of Tokushima
• Principal Investigator: MORIMOTO Masami 徳島大学, 病院, 特任助教 (90563817)
• Co-Investigator(Kenkyū-buntansha): 丹黒 章 徳島大学, 大学院医歯薬学研究部(医学域), 教授 (10197593) ; 鳥羽 博明 徳島大学, 大学院医歯薬学研究部(医学域), 助教 (40403745)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 乳房再建 / 乳腺幹細胞 / 乳汁分泌

Outline of Final Research Achievements

To generate the functional mammary gland, we focused on mammary stem cells (MaSCs) which are the local stem cells, and can differentiate to myoepithelial and luminal cells constructing the mammary gland. We could isolate the cell populations including 2.5% MaSCs from mammary glands of 8 weeks female mice. And then, we implanted these cells including MaSCs to mammary fat pads of 3 weeks female mice. After 4 weeks, the implanted cells could survive in the mammary fat pad. After 8 to 12 weeks, the implanted cells could form the mammary gland-like structures, and myoepithelial cells were recognized in some areas. Moreover, there were milk drop-like lesions produced inside the mammary gland-like structure.

Free Research Field

医歯薬学　乳腺外科学

Academic Significance and Societal Importance of the Research Achievements

乳癌の罹患率は増え，若年乳癌患者も増えている．若年乳癌患者の問題点としては，乳房切除によって乳汁分泌機能が失われることにある．乳汁産生機能を有する乳腺を再生することができれば非常に有意義であると考えた．そこで今回，われわれは，乳腺局所の幹細胞である乳腺幹細胞（Mammary stem cells: MaSCs）に着目した．まずマウスの乳腺からMaSCsを含む細胞の集団を単離し，マウスの乳腺近傍にある脂肪組織に移植した．移植4週後には細胞群が生着し，移植8～12週後には，一部で乳腺様の構造部分が確認できるとともに，乳管内に乳汁滴と思われる部分を確認することができた．