Pediatric Immunology
こどもの健康免疫

Takahito Takeuchi
担当：竹内　孝仁

New born immune system, which is initially protected by mother-derived IgG during several months after birth, then gradually matures depending on environmental factors. One of important environmental factors may be enteric microorganisms, which composition is altered by several factors such as food, hygiene, and vaginal delivery versus caesarean section. Appendix, which is composed of numerous lymphoid follicles, provides a major reservoir of enteric microorganisms. Interestingly, appendectomy underwent during early childhood has been reported to prevent the development of ulcerative colitis.
In addition, gut-associated lymphoid tissues (GALT) provides a place for the development of unique B cell subsets termed Regulatory B cells (Breg) and Regulatory plasma cells (Preg), both of which contribute for regulating immune responses to preserve healthy conditions.
Therefore, we strongly believe that dissecting out the immune mechanism played in the appendix and intestine would shed a light to understand the pediatric immune system for saving the lives of children who are facing potential risks of broad spectrum of diseases ranging from inflammatory bowel disease to autism.



子どもが秘める未知の免疫メカニズム

小児の免疫系は、生後数カ月は母体由来の免疫グロブリンIgGに依存し、その後は環境因子等に依存して徐々に確立されていく。免疫の成長に重要な役割を担う環境因子の一つは腸内微生物叢であり、この微生物叢の構成は食生活、衛生状態、分娩法（経腟分娩対帝王切開）など様々な因子により変動する。腸内微生物叢の主な貯留部位である虫垂には、膨大な数の免疫細胞が存在すると共に、幼少期の虫垂切除は潰瘍性大腸炎の発症を抑制することも疫学的に明らかとなっている。また、種々の自己免疫疾患及びアレルギー疾患に対して抑制的に働く”Breg”や”Preg”と呼ばれる新たなB細胞群も腸管免疫系には存在することも明らかとなってきている。よって、腸内微生物・虫垂免疫・新たなB細胞群・全身免疫の成長及び疾患に伴う関連性の包括的な解析により、小児の免疫系発達の機序を明らかにし、更に種々の小児疾患に対するBreg・Pregを利用した新たな細胞療法開発の基礎基盤構築のため日夜研究を続けている。



研究業績　受賞歴
Mizoguchi A, Takeuchi T, Himuro H, Okada T, and Mizoguchi E. Genetically engineered mouse models of IBD. J Pathol 238: 205-219, 2016

The 4th Annual Meeting of Asian Organization for Crohn's and Colitis 2016 Best Abstract Award　
Takahito Takeuchi, Atsushi Nishida, Jyunya Kizaki, Tetsushi Kinugasa, Yoshito Akagi, Toshiriro Noake, Yasumi Araki, Akira Andoh, Keiichi Mitsuyama, Atsushi Mizoguchi. Colonic IL-10 producing Plasmablasts in UC Patients.