Downes Andrew, Mouras Rabah, Bagnaninchi Pierre, Elfick Alistair
Centre for Biomedical Engineering, University of Edinburgh, Edinburgh EH9 3JL, UK.
J Raman Spectrosc. 2011 Oct;42(10):1864-1870. doi: 10.1002/jrs.2975.
The characterisation of stem cells is of vital importance to regenerative medicine. Failure to separate out all stem cells from differentiated cells before therapies can result in teratomas - tumours of multiple cell types. Typically, characterisation is performed in a destructive manner with fluorescent assays. A truly non-invasive method of characterisation would be a major breakthrough in stem cell-based therapies. Raman spectroscopy has revealed that DNA and RNA levels drop when a stem cell differentiates into other cell types, which we link to a change in the relative sizes of the nucleus and cytoplasm. We also used Raman spectroscopy to investigate the biochemistry within an early embryo, or blastocyst, which differs greatly from colonies of embryonic stem cells. Certain cell types that differentiate from stem cells can be identified by directly imaging the biochemistry with CARS microscopy; examples presented are hydroxyapatite - a precursor to bone, and lipids in adipocytes.
干细胞的特性鉴定对再生医学至关重要。在治疗前未能从分化细胞中分离出所有干细胞可能会导致畸胎瘤——一种包含多种细胞类型的肿瘤。通常，特性鉴定通过荧光检测以破坏性方式进行。一种真正非侵入性的鉴定方法将是基于干细胞疗法的重大突破。拉曼光谱显示，当干细胞分化为其他细胞类型时，DNA和RNA水平会下降，我们将其与细胞核和细胞质相对大小的变化联系起来。我们还使用拉曼光谱研究了早期胚胎或囊胚内的生物化学，其与胚胎干细胞集落有很大不同。某些从干细胞分化而来的细胞类型可以通过相干反斯托克斯拉曼散射（CARS）显微镜直接对生物化学进行成像来识别；给出的例子有羟基磷灰石——骨骼的前体，以及脂肪细胞中的脂质。
