EFFECT OF ANTIVIRALS ON HUMAN CORNEAL CELLS IN-VITRO

Toxic effects of 10 antiviral substances [9-(2-hydroxyethoxymethyl)-gu anine (ACV), E-5-(2-bromo vinyl)-2'-deoxyuridine (BVDU), 5-(2-chloroet hyl)-2'-deoxyuridine (CEDU), 9-(1,3-dihydroxy-2-propoxymethyl) guanine (DHPG), (S)-9-(3-hydroxy-2-phosphonylmethoxypropyl) adenine (HPMPA), (S)-1-(3-hydroxy-2-phosphonylmethoxypropyl) cytosine (HPMPC), 5'-iodo- 2'-deoxyuridine (IDU), phosphonoformic acid (PFA), 9-(2-phosphonylmeth oxyethyl) adenine (P MEA) and 5-trifluoromethyl-2'-deoxyuridine (TFT)I on uninfected human corneal cells were evaluated in two experimental models (undisturbed adherence and growth, and wound closure) under con tinuous drug exposure. The antiviral drugs were ranked in order of tox icity in each of the tests. The influence on toxicity of different exp erimental parameters such as initial cell density, length of exposure and trauma, was evaluated. There was significant interaction between t oxicity and length of exposure. In undisturbed cultures antiviral comp ounds ranked as follows: PMEA less than or equal to DHPG less than or equal to ACV less than or equal to CEDU < PFA less than or equal to ID U less than or equal to BVDU much less than HPMPC < TFT < HPMPA. Wound ing or migration increased the apparent toxicity of the antiviral subs tances; trauma did not have an additional effect. In conditions where corneal epithelium is poorly populated and ulcerated, wound healing ca n be delayed by antiviral medication.