Antonio R.L. Teixeira; Zulmira Lacava; Jaime M. Santana; Helena Luna
RESUMO
Observamos a cromatina deformas amastigotas de T. cruzi associada a cromossomos de macrófagos metafásicos obtidos em diversos períodos da infecção aguda. O estudo imunocitogenético demonstrou que o material genético inserido naqueles cromossomos era produto do T. cruzi. Pelo teste de hibridizaçâo in situ com sonda biotinilada de DNA de T. cruzi, foi confirmada a inserção de DNA do protozoário nos cromossomos murinos. A inserção seletiva de 3H-DNA do protozoário em alguns cromossomos sugere que podem ocorrer rearranjos transxenogénicos em infecções de mamíferos pelo T. cruzi.
Palavras-chaves: Trypanosoma cruzi. Macrófago. Transxenogene
SUMMARY
Trypanosoma cruzi chromatin was observed in macrophage chromosome spreads obtained at different periods of infections in BALB/c mice. Immunofluorescent studies showed that genetic materials associated with the chromosomes were T. cruzi products. In situ hybridization showed the protozoon DNA insertion in the host cell genome. In addition, selective 3H-DNA insertion in chromosomes 3, 6 and 11 was observed, which suggested that transxenogene rearrangement may take place in T. cruzi infections of mammals.
Keywords: Trypanosoma cruzi. Macrophage. Transxenogene.
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Endereço para correspondência:
Dr. Antonio R. L. Teixeira.
Laboratório de Imunologia/FCS/UnB. Caixa Postal 15
3121, 70910 Brasília, DF.
Recebido para publicação em 28/03/91.
