Toxoplasma gondii infection:: analysis of serological response by 2-DE immunoblotting

Toxoplasma gondii is known to cause a variety of diseases ranging from asymptomatic infections to serious conditions in immunocompromised hosts such as AIDS-patients or transplant recipients. In addition they may cause abortion or fetal abnormalities during pregnancy. Despite the clinical importance, diagnosis, treatment and prevention still remain unsatisfactory. Analysis of the parasitic cell determinants, recognized by specific humoral and cellular immune responses, may have important implications for diagnosis, therapy and vaccination strategies. Two-dimensional electrophoresis (2-DE) was used to resolve and compare protein patterns from Toxoplasma gondii strains RH and BK (mouse virulent strains). Comparison of silver-stained gels showed that 35.2% to 60.3% of the spots had the same position. In a second series of experiments, the reactivity of the spots with human sera was tested. Proteins were transferred to PVDF membranes and were detected with sera from different patient groups. Depending upon the immunoglobulin class (IgG, IgM, IgA or IE) different epitope patterns were observed. Some of the spots seemed to be recognized in different stages of infection. Sera of two patients with similar serology and comparable stage of infection were compared in order to demonstrate an individual immune response. (C) 1999 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.