Abstract

The value of hyperimmune gammaglobulin (HGG) therapy in ulcerative herpetic keratitis was assessed in rabbits. HGG treated of early disease in normal rabbits was very effective, producing a 10-fold rise in the virus concentration needed to infect 50% of sites (CID50) and an 88% inhibition of ulceration after 2 days. The efficacy of the gammaglobulin preparations tested depended on their anti-HSV antibody content. Established disease was considerably less responsive to HGG therapy. No conclusive effect of HGG therapy could be demonstrated in rabbits with a previous HSV skin infection ('immunised'). Corticosteroid-induced geographic ulceration in immunised rabbits was not prevented by concurrent HGG therapy. The findings indicate that HGG is unlikely to represent a useful therapy for ulcerative herpetic keratitis but that it may be valuable in primary disease and in long-term prophylaxis.