Science & Immunity:巨噬細胞的兩個不同來源

圖片來源：www.proglyta.com

2016年2月1日 訊 /生物谷BIOON/ --一直以來，科學家們對巨噬細胞的起源存在一定誤解，巨噬細胞作為一種白細胞在機體發育和免疫力上扮演著重要角色，近日來自新加坡A*STAR的科學家們利用一種新型技術證明了，在早期胚胎發育期間成體組織中的巨噬細胞有兩種來源。

巨噬細胞是人體包括大腦、肺部和腸道在內主要器官的重要組分，其可以「巡視」機體中的病原體，幫助誘發防禦機制並且吞食掉損傷的細胞；巨噬細胞同樣還可以抵禦多種疾病的發生，並且參與了多種癌症的發生過程，因此根據必要的反應，新型療法就會限制或者增強巨噬細胞的活性。

截止到2010年，科學家們都認為所有的巨噬細胞都會通過單核細胞的持續供給來進行補充，單核細胞是另外一種白細胞，隨後研究者就通過研究發現，位於大腦中的小神經膠質細胞實際上是來自於胚胎中的卵黃囊巨噬細胞。研究者Ginhoux說道，基於以上研究結果我們就提出了關於胚胎中巨噬細胞發育的一種系統性見解，而且我們還利用一種「預測命運圖譜」來對祖細胞進行標記並且追蹤其在成年各個階段的行為。

研究者對小鼠模型進行研究，對小鼠的胚胎巨噬細胞祖細胞進行了標記，當進行注射後巨噬細胞祖細胞就會釋放螢光，這就可以幫助研究者根據細胞的運動和分化來對其進行追蹤研究。研究者指出，這項研究就可以幫助我們證實卵黃囊巨噬細胞和胚胎單核細胞是來自早期和晚期的祖細胞；卵黃囊巨噬細胞可以產生小膠質細胞，同時胚胎單核細胞則會在其分化成為成體組織的巨噬細胞之前在其它組織中定植，隨後巨噬細胞就會進行自我更新。

下一步研究者將會通過深入研究來回答是否巨噬細胞的起源非常重要，從本質上來講這是一場「先天和後天」的爭辯，即是否巨噬細胞的起源會影響到晚期發育階段，甚至是正常情況和疾病狀況下細胞的功能和行為呢？而更加深入細緻的研究或許對於研究癌症起源和發展也至關重要。（生物谷Bioon.com）

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Florent Ginhoux1,2,*, Melanie Greter1, Marylene Leboeuf1, Sayan Nandi3, Peter See2, Solen Gokhan4, Mark F. Mehler4,5, Simon J. Conway6, Lai Guan Ng2, E. Richard Stanley3, Igor M. Samokhvalov7, Miriam Merad1,*

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