Effects of gamma-interferon on keratocyte-induced collagen gel contraction and keratocyte proliferation.

PURPOSE Gamma-interferon has been shown to be an effective immunoregulatory polypeptide that can modulate fibroblastic response. We investigated the effects of gamma-interferon on keratocyte proliferation and keratocyte-induced collagen gel contraction. METHODS Gamma-interferon in concentrations of 0.01, 1, 100, and 1000 U/ml of media was added to keratocytes embedded in polymerized type I collagen and the gel area was measured after 5 days with an image analysis system. The rate of keratocyte proliferation within and outside the collagen gel under the influence of gamma-interferon was also investigated. RESULTS Keratocyte-induced collagen gel contraction was significantly inhibited at all concentrations above 0.01 U/ml. The keratocyte proliferation was not affected by low and moderate concentrations and was significantly stimulated at concentration of 1000 U/ml. CONCLUSION Keratocyte-induced collagen gel contraction is inhibited by gamma-interferon and the mechanism of this effect is not inhibition of keratocyte proliferation by gamma-interferon.