Dunn G A, Ireland G W
Nature. 1984;312(5989):63-5. doi: 10.1038/312063a0.
When a confluent culture of 3T3 cells is wounded, new growth occurs at the wound margins. This indicates that the suppression of growth in the intact confluent sheet is under local control, a phenomenon known as 'topoinhibition', and it has been suggested that intercellular contact is responsible. An alternative explanation for topoinhibition is possible, however, namely that a soluble factor necessary for growth is locally depleted from the medium by cells so that each cell in a confluent sheet normally receives an insufficient supply and its growth is inhibited. Here we show that the pattern of release from topoinhibition in a wounded culture can be distorted simply by inducing a gentle laminar flow of medium across the wound. Growth remains suppressed at the upstream margin of the wound despite the reduced level of intercellular contact at wound edges. We conclude that the signal for topoinhibition is carried by the flow as would be predicted if it were the local depletion of growth factor.
当3T3细胞的汇合培养物受到损伤时，伤口边缘会出现新的生长。这表明完整汇合细胞层中生长的抑制受局部控制，这种现象称为“接触抑制”，有人认为细胞间接触是其原因。然而，对于接触抑制还有另一种解释，即生长所需的可溶性因子被细胞局部消耗，以至于汇合细胞层中的每个细胞通常供应不足，其生长受到抑制。在这里我们表明，只需在伤口上诱导培养基的平缓层流，就可以改变受伤培养物中接触抑制的释放模式。尽管伤口边缘的细胞间接触水平降低，但伤口上游边缘的生长仍然受到抑制。我们得出结论，接触抑制的信号是由流动携带的，这正如如果是生长因子的局部消耗所预测的那样。
