McConachie A, Newman D, Tucci M, Puckett A, Tsao A, Hughes J, Benghuzzi H
University of Mississippi Medical Center, Jackson, MS 39216, USA.
Biomed Sci Instrum. 1999;35:45-50.
Cell surface adhesion receptors interact with a family of adhesion molecules known as integrins. It is assumed that the cells recognize and bind a specific amino acid sequence. It is likely that the host inflammatory response may be mediated via the recognition of the inflammatory cells with the specific integrin molecules. The mechanism of such behavior has not been fully elucidated. This investigation was designed to provide more insight regarding the cellular response associated with incubation of macrophages with polymers either freely in solution or adhered to surfaces. Peripheral macrophages were seeded at a density of 4 x 10(6) cells on supports coated with either amino-acid heteropolymers of RGE, RGD, or amino-acid homopolymer Poly-L-lysine. Cells were also seeded at the same density in 24 well plates and the wells were treated with RGD, RGE or Poly-L-lysine. The cells were examined morphologically and biochemically at 24, 48, and 72 hours. The results showed cells growing on supports coated with RGD had significantly (p < 0.05) higher numbers of cells adhering and remaining viable, in comparison to cells growing on Poly-L-lysine or RGE supports. Cells growing on supports coated with RGE appeared irregularly (elongated and spindle) shaped and unevenly spaced. The cells growing on Poly-L-Lysine coated supports showed cellular disruption and lysis, whereas cells growing on the RGD appeared intact, regularly spaced and began fusing into giant cells. Lactate dehydrogenase activity was used as a measure of membrane integrity, and cells grown on coated supports with Poly-L lysine showed a two-fold increase in activity over control and peptide treated groups. On the other hand, cells growing in media containing the free RGE, RGD and Poly-L-lysine showed no statistical differences in cell number, and did not show increased activity of LDH for the entire duration of the experiment. The data suggests that the RGD, RGE and Poly-L-lysine dissolved in solution are highly biocompatible to the macrophages. However, when they are attached to a support they can affect cellular adherence as well as cellular activation.
细胞表面黏附受体与一类称为整合素的黏附分子相互作用。据推测，细胞识别并结合特定的氨基酸序列。宿主的炎症反应很可能是通过炎症细胞与特定整合素分子的识别来介导的。这种行为的机制尚未完全阐明。本研究旨在更深入地了解巨噬细胞与溶液中自由存在或附着于表面的聚合物孵育相关的细胞反应。将外周巨噬细胞以4×10⁶个细胞的密度接种在涂有RGE、RGD的氨基酸杂聚物或氨基酸同聚物聚-L-赖氨酸的载体上。细胞也以相同密度接种在24孔板中，并用RGD、RGE或聚-L-赖氨酸处理孔。在24、48和72小时对细胞进行形态学和生化检查。结果显示，与在聚-L-赖氨酸或RGE载体上生长的细胞相比，在涂有RGD的载体上生长的细胞黏附并保持存活的细胞数量显著更多（p<0.05）。在涂有RGE的载体上生长的细胞呈现不规则（细长和纺锤形）形状且间距不均匀。在聚-L-赖氨酸包被的载体上生长的细胞出现细胞破裂和裂解，而在RGD上生长的细胞看起来完整、间距规则并开始融合成巨细胞。乳酸脱氢酶活性用作膜完整性的指标，在聚-L-赖氨酸包被的载体上生长的细胞的活性比对照组和肽处理组增加了两倍。另一方面，在含有游离RGE、RGD和聚-L-赖氨酸的培养基中生长的细胞在细胞数量上没有统计学差异，并且在整个实验期间没有显示出LDH活性增加。数据表明，溶解在溶液中的RGD、RGE和聚-L-赖氨酸对巨噬细胞具有高度生物相容性。然而，当它们附着于载体时，它们会影响细胞黏附以及细胞活化。
