{"id":3535,"date":"2018-04-18T14:26:59","date_gmt":"2018-04-18T05:26:59","guid":{"rendered":"http:\/\/www.med.osaka-u.ac.jp\/eng\/?page_id=3535"},"modified":"2018-10-04T11:00:48","modified_gmt":"2018-10-04T02:00:48","slug":"nagasawa0418","status":"publish","type":"page","link":"https:\/\/www.med.osaka-u.ac.jp\/eng\/activities\/results\/2018year\/nagasawa0418","title":{"rendered":"NAGASAWA Takashi \u226aStem Cell Biology and Developmental Immunology\u226b <span>New light shed on how bone marrow niches keep stem cells thriving<\/span>"},"content":{"rendered":"<ul class=\"linkBar clearfix\">\n<li><a href=\"http:\/\/www.med.osaka-u.ac.jp\/activities\/results\/2018year\/18-03-29-nagasawa\">Text in Japanese<\/a><\/li>\n<\/ul>\n<p>2018-03-29<br \/><span class=\"lineFrame\">Publish<\/span> Genes &amp; Development \u00a0\u00a0 DOI: 10.1101\/gad.311068.117.<\/p>\n<p>Japanese researchers uncover cellular factor needed to maintain the environment that regulates hematopoietic stem cells<\/p>\n<p class=\"figure\"><img loading=\"lazy\" decoding=\"async\" class=\"alignleft wp-image-3539\" src=\"http:\/\/www.med.osaka-u.ac.jp\/eng\/wp-content\/uploads\/2018\/04\/795316b92fc766b0181f6fef074f03fa-4-400x300.png?_t=1524029312\" alt=\"\" width=\"500\" height=\"375\" srcset=\"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-content\/uploads\/2018\/04\/795316b92fc766b0181f6fef074f03fa-4-400x300.png 400w, https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-content\/uploads\/2018\/04\/795316b92fc766b0181f6fef074f03fa-4-768x576.png 768w, https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-content\/uploads\/2018\/04\/795316b92fc766b0181f6fef074f03fa-4-1024x768.png 1024w\" sizes=\"(max-width: 500px) 100vw, 500px\" \/><a href=\"http:\/\/www.med.osaka-u.ac.jp\/eng\/wp-content\/uploads\/2018\/04\/795316b92fc766b0181f6fef074f03fa-4.png\">\u00a0<span class=\"caption\">Figure1. CAR cells are specialized mesenchymal stem cells, which express the specific transcription factors, Ebf1\/3, inhibiting osteoblast differentiation to remain undifferentiated, maintain marrow cavities, enhance CXCL12 and SCF expression, and create HSC niches.\u00a0 \u00a0<\/span> <span class=\"click\">Click to enlarge<\/span><\/a><\/p>\n<p>Hematopoietic stem cells (HSCs) are a class of stem cells located in bone marrow. HSCs give rise to every type of blood cell\u2014from the red blood cells that carry oxygen to the white blood cells of the immune system. Bone marrow provides a niche that both houses and regulates HSCs to ensure proper formation of blood cells. However, the precise mechanisms that maintain the HSC niche are not fully understood.<\/p>\n<p>Now, in a new study published in Genes &amp; Development, researchers centered at Osaka University report they identified a key cellular protein involved in maintaining the bone marrow cavities and the HSC niche.<\/p>\n<p>The HSC niche is a microscopic, specialized environment located around blood vessels within the bone marrow. A wide array of cells and molecules have been found to reside in the niche and play a role in regulating HSCs. The researchers were especially interested in one particular cell type: chemokine ligand 12-abundant reticular (CAR) cells.<\/p>\n<p>\u201cSeveral lines of evidence from prior studies pointed to CAR cells as having a crucial function in the HSC niche,\u201d lead author Masanari Seike explains. \u201cWe wanted to take a closer look at specific proteins expressed in these cells, to really pinpoint what the cells were doing in the niche.\u201d<\/p>\n<p>The researchers found that a protein involved in regulating gene expression, called Ebf3, is highly abundant in CAR cells of mice. When they removed the gene that produces Ebf3 from these cells, they saw a significant decrease in the number of HSCs in the bone marrow\u2014as well as some other, more surprising effects.<\/p>\n<p>\u201cIn the absence of Ebf3, the stem cell population dropped fairly sharply, consistent with CAR cells playing a major role HSC regulation,\u201d Seike adds. \u201cWhat we didn\u2019t expect was the impact the removal would have on the shape of the niche itself. We found that bone density increased dramatically, essentially filling in the cavities that form niches. It appears the Ebf3-deficient CAR cells take on bone-synthesizing properties, similar to osteoblasts that typically make bone. We believe that CAR cells need Ebf3 to create the physical and molecular environment that ultimately becomes the HSC niche.\u201d<\/p>\n<p>The central role of Ebf3 in correctly balancing bone formation in the niche has significant clinical implications, and Ebf3 may eventually become a target of therapeutic interventions.<\/p>\n<p>\u201cOur findings suggest that drugs which modulate the activity of Ebf3 could have substantial clinical value,\u201d lead investigator Takashi Nagasawa notes. \u201cOn the one hand, Ebf3 inhibitors may be able to increase bone mass in diseases like osteoporosis. On the other, Ebf3 activators may allow for the fine-tuning of HSC niches, which would improve the effectiveness of regenerative therapies that allow patients to use their own stem cells. We hope this discovery opens up exciting new areas of exploration in both directions.\u201d<\/p>\n<p>&nbsp;<\/p>\n<p><b>The Article<\/b>: <b>\u00a0<\/b>\u201cStem cell niche-specific Ebf3 maintains the bone marrow cavity\u201d, was published in Genes &amp; Development at DOI: 10.1101\/gad.311068.117.<\/p>\n<p><strong>Summary<\/strong>: Hematopoietic stem cells (HSCs) require specialized niches in bone marrow to generate functional blood cells. CAR cells are among cell types located in niches, but their function is poorly understood. Researchers identified a protein, Ebf3, in CAR cells that is needed to maintain the bone marrow cavities and the HSC niche. With no Ebf3, HSC abundance is greatly reduced, and bone overgrowths fill the cavities forming the niches. The finding offers a new therapeutic target for bone and blood disorders.<\/p>\n<p><strong>Article<\/strong>: Stem cell niche-specific Ebf3 maintains the bone marrow cavity<br \/><strong>Journal<\/strong>:Genes &amp; Development<\/p>\n<p><strong>DOI<\/strong>:10.1101\/gad.311068.117<\/p>\n<p><strong>Authors<\/strong>: Masanari Seike, Yoshiki Omatsu, Hitomi Watanabe, Gen Kondoh and Takashi Nagasawa<\/p>\n<p><strong>Funding<\/strong>: Japan Society for the Promotion of Science \/ Uehara Memorial Foundation \/ Princess Takamatsu Cancer Research Fund<\/p>\n<p><strong>Primary Keyword<\/strong>: Biology<\/p>\n<p><strong>Additional Keywords<\/strong>: Cell Biology, Genetics, Molecular Biology<\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Text in Japanese 2018-03-29Publish Genes &amp; Development \u00a0\u00a0 DOI: 10.1101\/gad.311068.117. Japanese researcher [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":3539,"parent":3238,"menu_order":130,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"_links":{"self":[{"href":"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-json\/wp\/v2\/pages\/3535"}],"collection":[{"href":"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-json\/wp\/v2\/comments?post=3535"}],"version-history":[{"count":15,"href":"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-json\/wp\/v2\/pages\/3535\/revisions"}],"predecessor-version":[{"id":4055,"href":"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-json\/wp\/v2\/pages\/3535\/revisions\/4055"}],"up":[{"embeddable":true,"href":"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-json\/wp\/v2\/pages\/3238"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-json\/wp\/v2\/media\/3539"}],"wp:attachment":[{"href":"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-json\/wp\/v2\/media?parent=3535"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}