Salivary IgA and IgG Subclass Levels in Patients with Oral Lichen Planus - A Pilot Study

Oral lichen planus (OLP) is a chronic inflammatory disease which is characterized by an immunoreactivity directed against basal keratinocytes and mediated by T/lymphocytes. However, it is well known that salivary immunoglobulins have important role in the protection of mucosal surfaces. The aim of this study was to determine salivary immunoglobulin A1 (IgA1) and IgA2, together with IgG 1,2,3,4 subclass levels in patients with oral reticular lichen planus during acute stage and remission period as well as in comparison to the controls. In the whole resting saliva of 19 patients with OLP, age range 30-72, mean 58 years in acute phase and during remission period, and in 21 controls, age range 20-52, mean 35 years, salivary IgA and IgG subclasses were determined with radial immunodiffusion and enzyme immunoassay respectively. There were no significant differences in salivary IgG1 and IgG2 as well as IgA1 and IgA2 between patients in acute phase and controls (p>0.05). Patients in acute phase had significantly increased IgG3, IgG4 and proteins in comparison to the controls (p=0,021; p=0,004; p=0,029). No significant differences could be found between patients in acute phase and during remission period in IgG1,2,3,4 and IgA1 while IgA2 was significantly increased in acute phase in comparison to the remission period (p=0,049). Between patients in remission period and controls there were no significant differences in any IgA or IgG salivary subclasses (p>0,05). We can conclude that acute phase is characterized with increase in IgA2 which might reflect increased activity of secretory immunity as a possible result of microbial stimulation seen in acute phase in comparison to the remission period.