Human mast cell subtypes in conjunctiva of patients with atopic keratoconjunctivitis, ocular cicatricial pemphigoid and Stevens-Johnson syndrome

Abstract

Purpose: Investigate mast cell (MC S ) subtypes in atopic keratoconjunctivitis (AKC), ocular cicatrical pemphigoid (OCP), and Stevens-Johnson Syndrome (SJS). Methods: MC S subtypes were determined by immunohistochemistry of conjunctiva (obtained from 34 patients – 9 AKC, 9 OCP, 9 SJS and 7 normal) using monoclonal antibodies directed against chymase (MC C ) and tryptase (MC T ). Double staining was used to distinguish MC S as positive for both chymase and tryptase (MC TC ). Results: The number of MC S was significantly increased in AKC, OCP and SJS patients, compared to normal subjects. MC C were especially high in AKC, and moderately high in OCP. MC T and MC TC were similar in each disease group. Conclusions: While the AKC findings were not surprising, the result in OCP and SJS suggests that MC S play an underappreciated role in the inflammatory process of these disorders. Disparate proportions of MC S subtypes in these diseases may imply differential functions of MC S in these disorders.