Effects of early house dust mite exposure on the immunologic response in nasal mucosal cells of rhesus macaque monkeys

OBJECTIVE: The airway remodeling concept proposes that respiratory mucosa responds to allergens and toxins though inflammatory and immune-mediated responses that may persist even after exposure removal. House dust must (HDM) is a common allergen and a major cause of allergic disease. We aim to understand the effects of early house dust mite exposure in altering the immunologic response of nasal mucosal cells. STUDY DESIGN: Infant rhesus macaque monkeys were exposed to filtered air (FA) or episodic HDM. Animals were exposed to 11 3-day cycles of HDM during the first 6 months of life. All animals were raised in filtered air conditions until 3 years of age. METHODS: Sinonasal cells were harvested with necropsy. Cell cultures were grown, and cells were exposed to HDM in vitro at 10 ug/ml, 50 ug/ml, and 100 ug/ml. Enzymelinked immunosorbent assay (ELISA) was performed on cell apical and basolateral supernatant to measure IL-6 and IL-8 protein expression. RESULTS: HDM animals (n = 3) and FA animals (n = 5) showed dosedependent differences in relative IL-6 expression both apically and basolaterally. HDM animals showed significant increased relative IL-6 apical expression (p = 0.021) and decreased relative IL-6 basolateral expression (p = 0.033) at a high concentration of HDM exposure. No significant differences were seen in relative IL-8 expression between the treatment groups. CONCLUSION: Early HDM exposure increases relative apical IL-6 expression with high levels of HDM exposure. This effect is not seen with IL-8 expression. Early life allergen exposure may lead to apical remodeling in nasal mucosal cells with a persistent or enhanced IL-6 mediated immune response.