The Influence of Immunosuppressive Agents Upon Correal Wound Healing

Abstract

Azathioprine is the S-imidazolyl derivative of 6-mercaptopurine. Both of these purine analogues have proven antineoplastic and immunosuppressive properties.^1-10 While their precise mechanism of action in producing these effects is unknown, it is likely that separate modalities are involved. The immunosuppressive effects of purine analogues are presumed to be exerted by interference with adaptive metabolic processes occurring during the inductive phase of the immune response^5,6,8,10; the antineoplastic effects are generally attributed to their cytostatic or cytotoxic potential.¹⁰ The demonstrated efficacy of azathioprine in suppression of experimental corneal graft reactions^11,12 will naturally lead to its evaluation at the clinical level. However, the cytostatic or biosynthetic alterations, or both, induced by the drug on rapidly proliferating cells may be detrimental to corneal wound healing. Consequently, assessment of the effect of systemic azathioprine on corneal reparative processes was deemed mandatory. The studies reported herein indicate that systemic azathioprine is capable