別再讓您培養(yǎng)的細(xì)胞睡在硬板床上了??！

    *，體內(nèi)細(xì)胞所處周邊環(huán)境的軟硬度(softness，stiffness)可謂千差萬別，憑直覺想想脂肪細(xì)胞和骨細(xì)胞吧?？墒俏覀凅w外培養(yǎng)細(xì)胞時卻選擇使用了幾乎相同的材質(zhì)，硬邦邦的培養(yǎng)皿、板或培養(yǎng)瓶。
    你可能說：“這沒啥呀，大家不都是這樣做的嗎？我的細(xì)胞也長的挺好呀！”
    別再固執(zhí)的認(rèn)為細(xì)胞生長在“硬板床”上對其沒有什么影響了，大量的研究表明細(xì)胞所處環(huán)境的硬度對其生物學(xué)行為影響可謂相當(dāng)?shù)拇?。下面選擇幾篇CNS級別文章的摘要，感興趣的話可以下載讀一讀，即刻更新一下我們陳舊的觀點吧。

Matrix crosslinking forces tumor progression by enhancing integrin signaling. Cell. 2009 Nov 25;139(5):891-906.
SUMMARY
Tumors are characterized by extracellular matrix (ECM) remodeling and stiffening. The importance of ECM remodeling to cancer is appreciated; the relevance of stiffening is less clear. We found that breast tumorigenesis is accompanied by collagen crosslinking, ECM stiffening, and increased focal adhesions. Induction of collagen crosslinking stiffened the ECM, promoted focal adhesions, enhanced PI3 kinase (PI3K) activity, and induced the invasion of an oncogene-initiated epithelium. Inhibition of integrin signaling repressed the invasion of a premalignant epithelium into a stiffened, crosslinked ECM and forced integrin clustering promoted focal adhesions, enhanced PI3K signaling, and induced the invasion of a premalignant epithelium. Consistently, reduction of lysyl oxidase-mediated collagen crosslinking prevented MMTV-Neu-induced fibrosis, decreased focal adhesions and PI3K activity, impeded malignancy, and lowered tumor incidence. These data show how collagen crosslinking can modulate tissue fibrosis and stiffness to force focal adhesions, growth factor signaling and breast malignancy.
 
Matrix elasticity directs stem cell lineage specification.Cell. 2006 Aug 25;126(4):677-89.
SUMMARY
Microenvironments appear important in stem cell lineage specification but can be difficult toadequay characterize or control with soft tissues. Naive mesenchymal stem cells (MSCs)are shown here to specify lineage and commit tophenotypes with extreme sensitivity to tissuelevel elasticity. Soft matrices that mimic brainare neurogenic, stiffer matrices that mimic muscle are myogenic, and comparatively rigidmatrices that mimic collagenous bone proveosteogenic. During the initial week in culture,reprogramming of these lineages is possiblewith addition of soluble induction factors, butafter several weeks in culture, the cells committo the lineage specified by matrix elasticity,consistent with the elasticity-insensitive commitment of differentiated cell types. Inhibitionof nonmuscle myosin II blocks all elasticitydirected lineage specification–without stronglyperturbing many other aspects of cell functionand shape. The results have significant implications for understanding physical effects of thein vivo microenvironment and also for therapeutic uses of stem cells.
 
Role of YAP/TAZ in mechanotransduction. Nature. 2011 Jun 8;474(7350):179-83.
SUMMARY
Cells perceive their microenvironment not only through soluble signals but also through physical and mechanical cues,such as extracellular matrix (ECM) stiffness or confined adhesiveness. By mechanotransduction systems, cells translatethese stimuli into biochemical signals controlling multiple aspects of cell behaviour, including growth, differentiationand cancer malignant progression, but how rigidity mechanosensing is ultimay linked to activity of nucleartranscription factors remains poorly understood. Here we report the identification of the Yorkie-homologues YAP(Yes-associated protein) and TAZ (transcriptional coactivator with PDZ-binding motif, also known as WWTR1) asnuclear relays of mechanical signals exerted by ECM rigidity and cell shape. This regulation requires Rho GTPaseactivity and tension of the actomyosin cytoskeleton, but is independent of the Hippo/LATS cascade. Crucially, YAP/TAZ are functionally required for differentiation of mesenchymal stem cells induced by ECM stiffness and for survival ofendothelial cells regulated by cell geometry; conversely, expression of activated YAP overrules physical constraints indictating cell behaviour. These findings identify YAP/TAZ as sensors and mediators of mechanical cues instructed by thecellular microenvironment.
 
Substrate elasticity regulates skeletal muscle stem cell self-renewal in culture.Science. 2010 Aug 27;329(5995):1078-81.
SUMMARY
Stem cells that naturally reside in adult tissues, such as muscle stem cells (MuSCs), exhibit robustregenerative capacity in vivo that is rapidly lost in culture. Using a bioengineeredsubstrate to recapitulatekey biophysical and biochemical niche features in conjunction with a highly automated single-celltracking algorithm, we show that substrate elasticity is a potent regulator of MuSC fate in culture. UnlikeMuSCs on rigid plastic dishes (~106kilopascals), MuSCs cultured on soft hydrogel substrates that mimicthe elasticity of muscle (12 kilopascals) self-renew in vitro and contribute extensively to muscleregeneration when subsequently transplanted into miceandassayedhistologically and quantitatively bynoninvasive bioluminescence imaging. Our studies provide novel evidence that by recapitulatingphysiological tissue rigidity, propagation of adult muscle stem cells is possible, enabling future cell-basedtherapies for muscle-wasting diseases.

    需要更多關(guān)于細(xì)胞培養(yǎng)表面彈性對不同類型細(xì)胞的生物學(xué)行為影響的研究文獻(xiàn)？下面是針對不同組織細(xì)胞的另外一些例子：

    其實，要根據(jù)所培養(yǎng)細(xì)胞所處的體內(nèi)環(huán)境環(huán)境選擇相應(yīng)軟硬度的基質(zhì)，盡zui大可能保持細(xì)胞固有的特性并不難：Matrigen Life Technologies根據(jù)不同細(xì)胞類型設(shè)計生產(chǎn)了硬度各異的Softwell透明水凝膠，并已經(jīng)將這些水凝膠鋪設(shè)在我們常用細(xì)胞培養(yǎng)板、皿等用材的表面，用戶可以根據(jù)所培養(yǎng)細(xì)胞的體內(nèi)環(huán)境選擇相應(yīng)硬度的水凝膠培養(yǎng)板或培養(yǎng)皿，十分方便。

    Matrigen Life Technologies專一致力于重塑細(xì)胞培養(yǎng)之景象：你只需簡單的改變培養(yǎng)用品即可讓你的細(xì)胞培養(yǎng)條件更接近于體內(nèi)真實狀況。

    別擔(dān)心使用鋪設(shè)了水凝膠的培養(yǎng)皿（或板）對你的實驗結(jié)果會造成不良影響，softwell系統(tǒng)與各種實驗相兼容，不會干擾實驗結(jié)果；也不會因為有了這層薄薄的水凝膠而給你的實驗帶來麻煩：softwell不影響核酸和蛋白提取，不影響顯微鏡下觀測拍照-----