Leishmania ( Viannia) braziliensis: Influence of successive in vitro cultivation on the expression of promastigote proteinases

• Published in: Experimental parasitology Vol. 126; no. 4; pp. 570 - 576
• Main Authors: Rebello, Karina Mastropasqua, Britto, Constança, Pereira, Bernardo Acácio Santini, Pita-Pereira, Daniela de, Moraes, Milton Ozório, Ferreira, Anna Beatriz Robottom, Cysne-Finkelstein, Léa, Otto, Thomas Dan, Côrtes, Luzia Monteiro de Castro, da-Silva, Gabriel Gomes, Alves, Carlos Roberto
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01-12-2010; Elsevier
• Subjects: Animals; Biological and medical sciences; Cathepsin L-like; CPB gene; Cysteine Proteases - biosynthesis; Cysteine Proteases - genetics; Cysteine proteinases; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation, Enzymologic - physiology; Immunoblotting; Leishmania; Leishmania ( Viannia) braziliensis; Leishmania braziliensis - enzymology; Leishmania braziliensis - growth & development; Leishmania braziliensis - pathogenicity; Life cycle. Host-agent relationship. Pathogenesis; Macrophages, Peritoneal - parasitology; Mice; Mice, Inbred BALB C; pGlu-Phe-Leu-p Nitroanilide; Protozoa; Real-time PCR; Reverse Transcriptase Polymerase Chain Reaction; Serial Passage; trans-epoxysuccinyl l-leucylamido-(4-guanidino)butane; Virulence; Virulence Factors - biosynthesis; Virulence Factors - genetics; Cysteine proteinases; Real-time PCR; Cathepsin L-like; pGlu-Phe-Leu-p Nitroanilide; Leishmania ( Viannia) braziliensis; Kinetoplastida; Leishmania braziliensis; Leishmania (Viannia) braziliensis; Protozoa; Cathepsin L; Cysteine; Enzyme; Cysteine endopeptidases; Parasite; In vitro; Polymerase chain reaction; Peptidases; Cathepsin L-like, trans-epoxysuccinyl L-leucylamido-(4-guanidino)butane; Hydrolases; Promastigote
• ISSN: 0014-4894; 1090-2449
• DOI: 10.1016/j.exppara.2010.06.009

Cysteine proteinases are an important virulence factor in
Leishmania parasites. In this study we analyzed the cysteine proteinase expression of infective
Leishmania (
Viannia)
braziliensis promastigotes, examining the expression induced by successive
in vitro passages in culture. We observed that this parasite presents a decrease in its virulence over BALB/c macrophages, after successive passages in culture, but still they present proteinase activity, being capable of hydrolyzing the substrate pGlu-Phe-Leu-p Nitroanilide at pH 7.0. This proteinase activity also decreases in the course of the successive passages. Additionally, the decrease in the amount of CPB proteins following successive passages of promastigotes was verified by immunoblotting assays, using an anti-CPB antiserum. Real-time PCR assays were performed to assess the relative
cpb expression when compared to a housekeeping gene in promastigote cDNA preparations from the first, fourth and seventh passages. Interestingly, the data indicate a relative increase in
cpb gene transcripts as the promastigotes were maintained under
in vitro culture: 2.2 times higher for fourth and 2.7 times higher for seventh passages when compared to the first passage. Thus, the information gathered here shows that the expression of cysteine proteinases is modified during
in vitro cultivation of
L. (
V.)
braziliensis promastigotes.