TGFB1 and corneal infection: In addition, HC-HA/PTX3′s anti-scarring action, demonstrated in human corneal fibroblasts by downregulating the TGF-β1 promoter activity34 and its anti-angiogenic action by inhibition of endothelial tube formation35 may help explain why the resultant visual acuity is better in the AM group despite the baseline corneal ulcers were more centrally located.