HLA-DQ8 is a predisposing molecule for detergent enzyme subtilisin BPN′-induced hypersensitivity

Several million individuals are exposed to agents in the workplace associated with atopy and asthma. Detergent enzymes have been implicated in occupationally induced hypersensitivity. However, the genetic susceptibility and T cell responses to detergent enzymes are undefined. We generated and used HLA-DQ6, -DQ8, -DR2, -DR3, and -DR4 transgenic mice to examine the immune and inflammatory components involved in the response to the detergent enzyme subtilisin BPN′. Based on in vitro and in vivo studies, for the first time, we present evidence that DQ8 is a strong susceptibility marker for BPN′-induced hypersensitivity. Only DQ8 mice showed consistent T cell responses to five immunodominant regions of BPN′ comprising peptides #14 to 16, 36–37, 42–43, 62–63, and 80–81. The DQ8 mice also developed allergic eosinophilic inflammatory reactions in the airways following intranasal instillations of this enzyme. The DQ8 mice also responded to BPN′ with a significant IgG1 and IgE production. We propose that the HLA Class II tg mice are useful for understanding allergenic responses to enzymes in humans, screening of allergenic and immunogenic properties of detergent enzymes, and for the development of modified enzymes to maintain efficient detergent qualities without allergic properties.