Clonación de cDNAs que codifican para antígenos del parásito Toxocara canis


  • Lily Jiménez Y. Universidad de Chile
  • Ana Ledesma O. Universidad de Chile
  • Boris León R. Universidad de Chile
  • Juan Venegas H. Universidad de Chile


Toxocariasis is a parasite infectious disease provoked by worm larvae from Toxocara species. Different nematodes are involved in the pathogenesis of the disease, being Toxocara canis the most frequently found. The disease is known as "Larva migrans syndrorne" and it may involve any human organ, and in sorne cases cause a serious condition. This parasite has a worldwide distribution, affecting mainly children. Since it is very difficult to isolate it (direct diagnosis), serologic techniques have been mostly used to detect the presence of the parasite in the organism, being ELISA the one preferred, using excreted and secreted antigens by the parasite larva. Besides being a troublesome technique, it has been widely documented that it has cross reactions with a wide variety of other parasites. Our main goal is to improve these serologic methods, we proposed to start cloning cDNA that codifies T. canis recombinant antigens. Methods. We started to trace a T. canis cDNA gene library, using infected patients ' serum. Results - Conclusions. After a very arduous work we have been able to clone 2 cDNA made of 1500 and 900 pair of bases that would codify a recombinant protein still not described.

Palabras clave:

cDNA gene library, recombinant proteins, Toxocara canis


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