Lectin and its possible role in allergic rhinitis

Abstract

The incidence of respiratory allergic diseases such as bronchial asthma, allergic rhinitis and allergic bronchopulmonary aspergillosis is rising globally, including developing countries such as Egypt. Allergic rhinitis is inflammation in the nasal mucosa characterized by sneezing, nasal itching and discharge. It’s an IgE mediated immune reaction characterized by sensitization of mast cells upon exposure to certain allergens and release of multiple allergy mediators. Mannan-binding lectin (MBL), a protein of the innate immune system coded for by the MBL2 gene, constitutes an important effector molecule of innate immunity in the serum. It binds allergens/antigens, activates the lectin complement pathway and modulates the levels of proinflammatory cytokines. Earlier studies have reported elevated plasma MBL levels and complement activity in allergic patients. (Kaur et al., 2005; Uguz et al., 2005) The current study involved 60 adult patients with allergic rhinitis and 30 healthy medically free control subjects. There was no statistically significant difference between patients and control as regard gender or age. When serum MBL level was compared between cases and controls, a high statistically significant difference was detected, with higher mean ±SD for serum mbl level (564.667 ± 282.3 ng/ml) in allergic rhinitis patients than control subjects. On comparing serum MBL level among various study parameters only statistically significant difference was detected between patients with mild AR and those with moderate to severe AR. Although there was a positive correlation between MBL serum level and age and duration of illness (yrs), there was no statistical significance as well as an inverse correlation with serum total IgE level.