ABNORMAL IMMUNE FUNCTION IN MALIGNANT HYPERTENSION

Objective: To investigate the extent to which the immune system is inf luenced in patients with previous malignant hypertension. Design: Twen ty-three patients with malignant hypertension (fundus hypertonicus gra des III or IV) in the Gothenburg area were studied over a 3-year perio d. After treatment had been instituted they were investigated to estab lish the function of the cellular immune system (number of T lymphocyt es and the proliferative response to T-cell mitogens), human leucocyte antigens A, B and C and frequency of autoantibodies. Methods: The num bers of T lymphocytes were quantified as erythrocyte rosettes. Lymphoc yte-stimulation tests were carried out using the T-cell mitogens phyto haemagglutinin and concanavalin-A. Autoantibodies were determined with immunoassay techniques and leucocyte A, B and C antigens with a lymph ocytotoxicity test. Results: The frequency of T lymphocytes and their baseline thymidine incorporation were significantly depressed in patie nts with previously malignant hypertension compared with control subje cts. The group with malignant hypertension also had a decreased prolif erative response to concanavalin-A but not to phytohaemagglutinin, and they had an increased frequency of antinuclear antibodies. Human leuc ocyte antigen B15 tended to occur more frequently in patients with mal ignant and non-malignant hypertension than in control subjects, especi ally if a family history of hypertension was taken into consideration. Conclusion: The results from the present study indicate that immune m echanisms are involved in malignant hypertension, either secondary to the vascular damage or as a primary abnormality.