The effects of single doses of b radiation on the wound healing behaviour of human Tenon’s capsule fibroblasts

Aim: To determine the effects of single doses of b radiation on the wound healing functions of human Tenon’s capsule fibroblasts (hTf). Methods: hTf were grown in tissue culture and irradiated with b radiation using a strontium 90 source. The effects of b radiation on fibroblast migration was studied using microporous transwell membranes. The effects of radiation on fibroblast contraction was investigated using a fibroblast populated collagen gels model. Production of extracellular matrix molecules (collagen I, collagen III, and fibronectin) by monolayers of irradiated fibroblasts was quantified for 14 days following single doses of b radiation. Results: Growth inhibiting doses of b radiation did not inhibit fibroblast migration or contraction at any time point. Levels of soluble fibronectin from irradiated populations were significantly reduced after .500 cGy b radiation. Collagen I and III levels were not reduced after any dose of radiation, and increased following treatment with 1000 cGy b radiation. Conclusions: Growth arresting doses of b radiation have unique effects on the wound healing behaviour of human Tenon’s capsule fibroblasts. There was no significant effect on cellular migration or contraction, but ECM production was altered. Fibronectin production was inhibited following higher radiation doses, and collagen I and III production increased after 1000 cGy. The effects of single doses of b radiation on ocular fibroblast wound healing behaviour are very different from those of 5-fluorouracil and mitomycin C, and these differences may be exploited clinically in the regulation of wound healing after glaucoma filtration surgery.