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    近日，英國謝菲爾德大學Marcelo Rivolta教授帶領(lǐng)的研究團隊將人類的胚胎干細胞分化為止關(guān)重要的聽覺細胞，從而治愈了耳聾的沙鼠。相關(guān)論文發(fā)表在9月12日的Nature雜志上。

    耳聾主要是因為聽覺毛細胞（sensory hair cell）或與之相作用的耳蝸螺旋神經(jīng)節(jié)神經(jīng)元（spiral ganglion neurons，SGNs）受損所致。SGNs負責將毛細胞接收的信號傳遞給大腦。聽覺神經(jīng)病變（auditory neuropathy）發(fā)病率最高，這類病人的毛細胞完好，但SGNs受損。盡管受損的毛細胞可以通過人工耳蝸移植治愈，但是SGNs的受損尚無法通過常規(guī)方法治療。

    在這一研究中，研究人員采用纖維母細胞生長因子（fibroblast growth factor）FGF3和FGF10將人胚胎干細胞誘導(dǎo)分化耳祖細胞（otic progenitors），進而分化為SGNs，而后移植到聽覺神經(jīng)病變的沙鼠中。10周以后，用電極測定大腦對于聲音的反應(yīng)，發(fā)現(xiàn)這些沙鼠的聽力平均恢復(fù)了46%。所用聲音大小在50分貝左右，相當于安靜環(huán)境中的談話聲。

    雖然這一方法尚無法應(yīng)用于耳聾的人，但是為干細胞治療耳聾開辟了道路。

    編譯自In gerbils, stem cells boost hopes of ending deafness

    Nature原文：

    Restoration of auditory evoked responses by human ES-cell-derived otic progenitors

    Wei Chen,1, 2, 4 Nopporn Jongkamonwiwat,1, 2, 3, 4 Leila Abbas,1, 2 Sarah Jacob Eshtan,1, 2 Stuart L. Johnson,2 Stephanie Kuhn,2 Marta Milo,2 Johanna K. Thurlow,1, 2 Peter W. Andrews,1, 2 Walter Marcotti,2 Harry D. Moore1, 2 & Marcelo N. Rivolta1, 2

    Deafness is a condition with a high prevalence worldwide, produced primarily by the loss of the sensory hair cells and their associated spiral ganglion neurons （SGNs）。 Of all the forms of deafness, auditory neuropathy is of particular concern. This condition, defined primarily by damage to the SGNs with relative preservation of the hair cells1, is responsible for a substantial proportion of patients with hearing impairment2. Although the loss of hair cells can be circumvented partially by a cochlear implant, no routine treatment is available for sensory neuron loss, as poor innervation limits the prospective performance of an implant3. Using stem cells to recover the damaged sensory circuitry is a potential therapeutic strategy. Here we present a protocol to induce differentiation from human embryonic stem cells （hESCs） using signals involved in the initial specification of the otic placode. We obtained two types of otic progenitors able to differentiate in vitro into hair-cell-like cells and auditory neurons that display expected electrophysiological properties. Moreover, when transplanted into an auditory neuropathy model, otic neuroprogenitors engraft, differentiate and significantly improve auditory-evoked response thresholds. These results should stimulate further research into the development of a cell-based therapy for deafness.