COL1A1 and infection: We have shown that for more than a year after infection with O. felineus: (i) amount of connective tissue increased significantly (without reaching a plateau); (ii) deposition of collagen type 1 increased with a significant increase in the expression of the Col1a1 gene at week 52 p.i.; (iii) Mmps/TIMP imbalance was detected at all stages of infection.