Improvement of HSV-1 necrotizing keratitis with amniotic membrane transplantation. – PubMed
RESULTS: All children presented with dendritic or punctate epithelial keratitis, and stromal keratitis occurred concurrently with epithelial keratitis in 14 patients (61%). One favored mechanism to explain the role of viruses in the genesis of autoimmunity is molecular mimicry. In this review we discuss the pathogenesis of HSK referring to work mainly done using animal model systems. In this study, the effect of amniotic membrane transplantation (AMT) on corneal wound healing and on inflammation in mice with necrotizing HSK was examined. BALB/c mice were corneally infected with 10(5) plaque-forming units (PFU) of HSV-1 (KOS strain). More importantly, animals infected with HSV failed to develop responses that reacted with either peptide, and infection with a recombinant vaccinia UL6 vector failed to cause HSK, in spite of generating UL6 reactivity. Corneas in 16 infected mice remained uncovered and served as a control.
On days 2 and 7 after surgery, the amniotic membrane was removed (eight mice in each group), the HSV-1-infected cornea was evaluated clinically, and the eye was enucleated. Tissue sections were analyzed histologically for epithelialization and cellular infiltration and immunohistochemically with anti-CD3 mAb to T cells, anti-CD11b mAb to both macrophages and neutrophils, or anti-F4/80 mAb to macrophages. Profound regression of corneal inflammation and rapid closure of epithelial defects were observed clinically within 2 days in the amniotic membrane-covered eyes, whereas HSV-1 keratitis and ulceration progressed in all mice in the control group (P < 0.001). Histologically, corneal edema and inflammatory infiltration, and immunohistochemically the number of CD3(+), CD11b(+), and F4/80(+) cells in the cornea were markedly decreased at 2 and 7 days after amniotic membrane application, compared with the uncovered control corneas (P < 0.001). AMT promotes rapid epithelialization and reduces stromal inflammation and ulceration in HSV-1 keratitis. AMT in mice with HSV necrotizing stromal keratitis appears to be a useful model for investigating the effect and the action mechanism of human amniotic membrane.