SUPEROXIDE DISMUTASES IN HUMAN PALATINE TONSILS

In order to investigate the protective system of human palatine tonsil s against the cytotoxic superoxide radicals (O-2(-)) generated from th e oxygen-related bactericidal system, immunohistochemistry and electro n spin resonance (ESR) spectrometry were used to detect the distributi on and activities of superoxide dismutases (SODs) in tonsils of differ ent related systemic diseases. Immunohistochemistry showed that SODs d istribute in extrafollicular lymphatic tissue and crypt epithelium. No distribution difference could be found between tonsils of different r elated systemic diseases. ESR revealed no significant difference betwe en SODs activities in tonsils of different related systemic diseases. However, the mitochondrial SOD activity was found to constitute approx imately 50%-60% of the total tonsillar cellular SODs activity. The res ults suggest: i) tonsils possess the ability to control cytotoxic O-2( -), ii) crypt epithelium and extrafollicular lymphatic tissue may enco unter more O-2(-) threat, iii) SODs may be important in protecting ger minal centers from O-2(-) injury, and iv) systemic diseases are less r elated to the local expression of tonsillar SODs.