Leblanc G G, Holbert T E, Darland T
Department of Biological Structure and Function, Oregon Health Sciences University, Portland 97201, USA.
J Neurobiol. 1995 Apr;26(4):497-510. doi: 10.1002/neu.480260404.
Cranial and trunk neural crest cells produce different derivatives in vitro. Cranial neural crest cultures produce large numbers of cells expressing fibronectin (FN) and procollagen I (PCol I) immunoreactivities, two markers expressed by mesenchymal derivatives in vivo. Trunk neural crest cultures produce relatively few FN or PCol I immunoreactive cells, but they produce greater numbers of melanocytes than do cranial cultures. Treatment of trunk neural crest cultures with transforming growth factor-beta 1 (TGF-beta 1) stimulates them to express both FN and PCol I immunoreactivities at levels comparable to those normally seen in cranial cultures and simultaneously decreases their expression of melanin. These observations raised the possibility that endogenous TGF-beta is involved in specifying differences in the phenotypes expressed by cranial and trunk neural crest cells in vitro. Consistent with this idea, we found that treatment of cranial cultures with a function-blocking TGF-beta antiserum inhibits the development of FN immunoreactive cells and stimulates the development of melanocytes. Cranial and trunk neural crest cells express approximately equal levels of TGF-beta mRNA. However, trunk neural crest cells are significantly less sensitive to the FN-inducing effect of TGF-beta 1 than are cranial neural crest cells. These results suggest that: (1) endogenous TGF-beta is required for the expression of mesenchymal phenotypes by cranial neural crest cells, and (2) differences in the phenotypes expressed by cranial and trunk neural crest cells in vitro result in part from differences in the sensitivities of these two cell populations to TGF-beta.
颅神经嵴细胞和躯干神经嵴细胞在体外产生不同的衍生物。颅神经嵴细胞培养物产生大量表达纤连蛋白（FN）和I型前胶原（PCol I）免疫反应性的细胞，这是体内间充质衍生物表达的两种标志物。躯干神经嵴细胞培养物产生相对较少的FN或PCol I免疫反应性细胞，但它们产生的黑素细胞数量比颅神经嵴细胞培养物更多。用转化生长因子-β1（TGF-β1）处理躯干神经嵴细胞培养物，可刺激它们表达FN和PCol I免疫反应性，其水平与颅神经嵴细胞培养物中正常所见水平相当，同时降低它们的黑色素表达。这些观察结果提出了一种可能性，即内源性TGF-β参与了体外颅神经嵴细胞和躯干神经嵴细胞所表达表型差异的特异性调控。与此观点一致，我们发现用功能阻断型TGF-β抗血清处理颅神经嵴细胞培养物会抑制FN免疫反应性细胞的发育，并刺激黑素细胞的发育。颅神经嵴细胞和躯干神经嵴细胞表达的TGF-β mRNA水平大致相等。然而，躯干神经嵴细胞对TGF-β1诱导FN表达的作用比颅神经嵴细胞明显不敏感。这些结果表明：（1）内源性TGF-β是颅神经嵴细胞表达间充质表型所必需的；（2）体外颅神经嵴细胞和躯干神经嵴细胞所表达表型的差异部分源于这两种细胞群体对TGF-β敏感性的差异。
