HLA-DR antigen expression in tonsillar epithelium. With special reference to focal infection.

Palmoplantar pustulosis (PPP) has long been regarded as a tonsillar focal infection because tonsillectomy is so effective in its treatment. Immune mechanisms of focal infection have been discussed mainly with regard to humoral immunity as an autoimmune disease. The present immunological study demonstrates the expression of HLA-DR antigen in tonsillar epithelium. The patterns of the HLA-DR antigen appearance in the epithelium were categorized into 4 types, and the intensity was compared between hypertrophic tonsils, recurrent tonsillitis, and tonsils with PPP. In addition, paired fluorescent staining, a combination of CD3 and anti-HLA-DR antibodies, was performed. The activity of intraepithelial T-lymphocytes was determined as an index of the HLA-DR antigen expression. In an age matching study, HLA-DR antigen appeared in high intensity in tonsils with PPP. A close correlation was found between the appearance of HLA-DR antigens and activation of infiltrating T-lymphocytes. These findings suggest that the tonsillar epithelium plays an important role in focal infection.