Although negative pressure wound therapy (NPWT) has been suggested for the management of acute and chronic wounds, the underlying mechanism of NPWT on the cellular level is not fully understood. Using a primary fibroblast culture model with controlled negative pressure, the cellular responses to the negative pressure was investigated. The present results showed that cell proliferation of fibroblasts was not affected under negative pressure. The mRNA expressions of collagen type I, collagen type Ill, and fibronectin were down-regulated when cells treated with negative pressure for once only. However, those mRNA expressions were up-regulated when cells subjected to periodical negative pressure consecutively for 5 days. The protein production of TGF-beta 1 was enhanced, while the TIMP-1, decorin, and IL-6 were not influenced. The pro-MMP-9 was not stimulated when fibroblasts subjected to negative pressure. The regulations of extracellular matrix production in fibroblasts provides an insight into the cellular mechanisms of NPWT. (C) 2015 Elsevier Ltd. All rights reserved.