Reduced activity of matrix metalloproteinase-9 in trypanosoma cruzi-infected mouse embryo hepatocyte cell.
In this work, we are reporting differences in the proteolytic profile of Trypanosoma cruzi-infected and non-infected primary cultures of mouse embryo hepatocyte cells. In gelatin-SDS-PAGE, ours results showed the presence of a 100kDa metalloproteinase in the supernatant and in the cells of both systems and an 85kDa extracellular metalloproteinase found only in the non-infected hepatocyte cultures. An enzymatic assay using gelatin as substrate showed a decrease of 74 and 70% in metalloproteinase activity in the culture supernatant and in the cell hepatocyte system infected with T. cruzi, respectively. Western blotting analysis using anti-matrix metalloproteinase-9 (MMP-9) antibody recognized the 100 and 85kDa protein bands, indicating that hepatocyte metalloproteinases correspond to the latent and active forms of the gelatinase MMP-9, respectively. The localization of MMP-9 was established by immunocytochemistry analysis in the cytoplasm of the non-infected and infected hepatocyte cells. In normal and infected hepatocyte cells, cysteine-proteinases migrating in gelatin-SDS-PAGE at 60kDa were detected and should correspond to lysosomal cysteine-proteinases of T. cruzi (cruzipain) and hepatocytes. In T. cruzi-infected hepatocytes an increase of approximately 50% in this enzymatic activity was observed, possibly due to parasite's cruzipain.
Nogueira de Melo
Ana Cristina
AC
Department of General Microbiology, Institute of Microbiology Prof Paulo de Góes, Federal University of Rio de Janeiro, CCS, Bl I, 21941-590, RJ, Rio de Janeiro, Brazil
Meirelles
Maria Nazareth L.
MN
Porrozzi
Renato
R
Costa
Juliana Dias
JD
Branquinha
Marta Helena
MH
Vermelho
Alane Beatriz
AB