McFarland Kevin L, Glaser Kathryn, Hahn Jennifer M, Boyce Steven T, Supp Dorothy M
Research Department, Shriners Hospitals for Children, Cincinnati, Ohio 45229, USA.
J Burn Care Res. 2011 Jul-Aug;32(4):498-508. doi: 10.1097/BCR.0b013e3182223cb1.
Fibroblasts, the main cell type of the dermis, are responsible for production and remodeling of extracellular matrix during wound healing. Disruption of either production or degradation of extracellular matrix can lead to abnormal scarring, resulting in hypertrophic scar or keloid scar. Aberrations in proliferation and gene expression have been observed in fibroblasts isolated from abnormal scars, but differences observed may be related to biologic responses to growth conditions and media formulations. This study examined gene expression in primary human fibroblasts from normal skin or abnormal scar in two culture media formulations and three relative cell densities. In general, higher expression of collagen type 1 alpha-1 (COL1A1) and alpha-2 (COL1A2) and matrix metalloproteinase 3 (MMP3) and lower levels of MMP1 were observed in all cell strains cultured in standard medium containing 10% fetal bovine serum compared with cells cultured in medium optimized for proliferation. Normal and scar-derived fibroblasts exhibited differences in gene expression in specific response to media formulations and cell density. COL1A1 and COL1A2 were increased, and MMP1 and MMP3 were decreased, in keloid cells compared with normal fibroblasts under most conditions analyzed. However, expression of plasminogen activator inhibitor 1 in keloid fibroblasts, which was significantly different than in normal fibroblasts, was either increased or decreased in response to the medium formulation and relative cell density. A related gene, plasminogen activator inhibitor 2, was shown for the first time to be significantly increased in keloid fibroblasts compared with normal fibroblasts, in both media formulations and at all three cell densities. The results emphasize the critical role of culture conditions in interpretation of cell behavior and expression data and for comparison of cells representing normal and fibrotic phenotypes.
成纤维细胞是真皮的主要细胞类型，在伤口愈合过程中负责细胞外基质的产生和重塑。细胞外基质产生或降解的破坏可导致异常瘢痕形成，从而产生增生性瘢痕或瘢痕疙瘩。在从异常瘢痕中分离出的成纤维细胞中观察到增殖和基因表达的异常，但观察到的差异可能与对生长条件和培养基配方的生物学反应有关。本研究在两种培养基配方和三种相对细胞密度下，检测了来自正常皮肤或异常瘢痕的原代人成纤维细胞中的基因表达。一般来说，与在优化用于增殖的培养基中培养的细胞相比，在含有10%胎牛血清的标准培养基中培养的所有细胞株中，观察到Ⅰ型胶原蛋白α-1（COL1A1）和α-2（COL1A2）以及基质金属蛋白酶3（MMP3）的表达较高，而MMP1的水平较低。正常和瘢痕来源的成纤维细胞在对培养基配方和细胞密度的特异性反应中表现出基因表达的差异。在大多数分析条件下，与正常成纤维细胞相比，瘢痕疙瘩细胞中的COL1A1和COL1A2增加，而MMP1和MMP3减少。然而，瘢痕疙瘩成纤维细胞中纤溶酶原激活物抑制剂1的表达与正常成纤维细胞相比有显著差异，其表达会因培养基配方和相对细胞密度而增加或减少。首次发现，在两种培养基配方和所有三种细胞密度下，与正常成纤维细胞相比，瘢痕疙瘩成纤维细胞中相关基因纤溶酶原激活物抑制剂2均显著增加。这些结果强调了培养条件在解释细胞行为和表达数据以及比较代表正常和纤维化表型的细胞方面的关键作用。
