[Measles vaccination in the Sudan-Sahel region of Africa. Absence of the immunodepressive effect of malaria]. / Vaccination antirougeoleuse en afrique soudano-sahelienne. Absence d'effet immunodépresseur du paludisme.

A survey aiming at assessing the effectiveness of anti-measles vaccination was carried out in a rural Upper-Volta population. The haemagglutination inhibition technique was used for detection of anti-measles antibodies; a reciprocal antibody titer of 20 or more was considered as a positive one and the subject considered as immunized. In the age group of 1-3 years old studied here, malaria does not seem to be a factor that modulates the ability of vaccinated subjects of producing anti-measles antibodies. Thus the immunodepressive properties of the Plasmodium is not observed in this immunizing system which effectiveness has been further improved by the development of thermostable vaccines.

Relevance of autoantigens to autoimmunity in African trypanosomiasis: study of DNA and thyroglobulin antibodies.

In order to investigate whether the autoantibody production in the course of African trypanosomiasis is the result of a generalized polyclonal activation or if it is a specific (antigen-dependent) phenomenon we looked for the presence of autoantibodies directed against autoantigens likely to be released (DNA) or unlikely to be released (thyroglobulin) into the circulation during human T. gambiense infection. Sera from 21 patients with African trypanosomiasis were screened for anti-native DNA or anti-denatured DNA antibodies by a Farr DNA binding radioimmunoassay. In addition, antibodies to native DNA were also assessed by indirect immunofluorescent assays using Crithidia luciliae or rat liver sections as substrates. Anti-thyroglobulin antibodies were studied by the passive hemagglutination technique. IgM levels and fluorescent anti-trypanosomal antibodies (FATA) were concomitantly evaluated. The denaturated DNA binding capacity was significantly higher in the sera from trypanosomiasis patients than in sera from healthy blood donors. These capacities were greater in patients with high IgM levels and high FATA titres. Anti-native DNA or anti-thyroglobulin antibodies were not detected. This preferential formation of anti-denatured DNA antibodies suggests a specific antigen-dependent) activation of autoreactive cells rather than a generalized polyclonal activation.