Sera of patients with systemic lupus erythematosus react with plasmodial antigens and can inhibit the in vitro growth of Plasmodium falciparum.
The acquisition of protective immunity in malaria is a slow process during which autoantibodies are produced. The present work aimed at studying a possible interference of autoimmune responses on malaria immune protection. This was done by investigating the presence of autoantibodies in the sera of malarious patients, by searching for reactivity of autoantibodies from autoimmune patients against plasmodial antigens, and by studying the effect of such antibodies on the in vitro growth of Plasmodium falciparum. Sera from systemic lupus erythematosus (SLE) and malaria patients were tested against autologous and plasmodial antigens. Out of the 109 SLE sera tested, 48 (44%) reacted against the parasite. In addition, 26 (47%) out of 55 randomly selected sera, mainly those containing anti-DNA and antinuclear autoantibodies, were able to inhibit parasite growth to some extent. Conversely, a high frequency (81%) of sera of malaria patients exhibited reactivity against autoantigens. The results show that patients with autoimmune processes can produce antibodies that recognize plasmodial antigens in the absence of plasmodial infection, that malaria patients can produce autoantibodies, that SLE sera can inhibit plasmodial growth in vitro, and that the presence of anti-DNA and antinuclear antibodies may be important in such anti-plasmodial activity. It is concluded that autoimmune responses may have influence on the protective immunity against malaria.
Zanini
Graziela Maria
GM
Instituto Oswaldo Cruz and Center for Malaria Research and Training - Fiocruz, Rio de Janeiro, Brazil.
De Moura Carvalho
Leonardo Jose
LJ
Brahimi
Karima
K
De Souza-Passos
Luiz Fernando
LF
Guimarães
Swami Jose
SJ
Da Silva Machado
Eduardo
E
Bianco-Junior
Cesare
C
Riccio
Evelyn Kety Pratt
EK
De Sousa
Maria Auxiliadora
MA
Alecrim
Maria Das Gracas Costa
MD
Leite
Nocy
N
Druilhe
Pierre
P
Daniel-Ribeiro
Claudio Tadeu
CT
D000818:Animals; D000953:Antigens, Protozoan / Q000276:immunology* / Q000378:metabolism; D001323:Autoantibodies / Q000276:immunology* / Q000494:pharmacology; D003429:Cross Reactions; D006801:Humans; D007106:Immune Sera / Q000276:immunology* / Q000494:pharmacology; D008180:Lupus Erythematosus, Systemic / Q000097:blood* / Q000276:immunology; D010963:Plasmodium falciparum / Q000187:drug effects* / Q000254:growth & development / Q000276:immunology*
D000953:Antigens, Protozoan; D001323:Autoantibodies; D007106:Immune Sera