Hostname: page-component-cd9895bd7-dk4vv Total loading time: 0 Render date: 2024-12-27T02:21:57.476Z Has data issue: false hasContentIssue false
  • English
  • Français

Intracellular differentiation of Leishmania amazonensis promastigotes to amastigotes: presence of megasomes, cysteine proteinase activity and susceptibility to leucine-methyl ester

Published online by Cambridge University Press:  06 April 2009

L. Galvao-Quintao ,
S. C. Alfieri ,
A. Ryter  and
M. Rabinovitch
L. Galvao-Quintao
Affiliation:
Unité d’ Immunoparasitologie, Institut Pasteur et CNRS (URA 361)
S. C. Alfieri
Affiliation:
Unité d’ Immunoparasitologie, Institut Pasteur et CNRS (URA 361)
A. Ryter
Affiliation:
Unité de Microscopie électronique, Institut Pasteur et CNRS (URA 1148), 25 rue du Dr Roux, 75724 Paris Cedex 15, France
M. Rabinovitch
Affiliation:
Unité d’ Immunoparasitologie, Institut Pasteur et CNRS (URA 361)
Get access Rights & Permissions [Opens in a new window]

Summary

Intracellular differentiation of Leishmania promastigotes to amastigotes is a critical step in the establishment of infection. In this report three related features of mexicana subspecies amastigotes were used to follow the differentiation of the parasites within macrophages. Early after infection, (a) parasites did not contain ultrastructurally recognizable megasomes, (b) cysteine proteinase activity of parasite lysates was not detected in gelatin-containing acrylamide gels, and (c) parasites were essentially resistant to L-leucine-methyl ester (Leu-OMe). Typical megasomes were first identified on the 5th day, were more prevalent on day 7, and underwent swelling in macrophages exposed to Leu-OMe. Cysteine proteinase activity was first detected on day 3 and increased thereafter. Susceptibility to Leu-OMe of parasites studied in situ or isolated from infected macrophages increased with time of intracellular residence and by 7 days approached that of amastigotes isolated from mouse lesions. In contrast, parasites derived from either promastigotes or amastigotes were equally susceptible to another leishmanicidal compound, tryptophanamide (Trp-NH2). The results provide additional support for the involvement of megasomes and their cysteine proteinases in parasite killing by Leu-OMe, and highlight the slow pace of the intracellular differentiation of L. amazonensis promastigotes to amastigotes.

Keywords

Leishmania amazonensismegasomecysteine proteinasesleucine-methyl ester
Type
Research Article
Information
Parasitology , Volume 101 , Issue 1 , August 1990 , pp. 7 - 13
Copyright
Copyright © Cambridge University Press 1990

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Alfieri, S. C., Ramazeilles, C., Zilberfarb, V., Galpin, I., Norman, S. E. & Rabinovitch, M. (1988). Proteinase inhibitors protect Leishmania amazonensis amastigotes from destruction by amino acid esters. Molecular and Biochemical Parasitology 29, 191–201.CrossRefGoogle ScholarPubMed
Alfieri, S. C., Shaw, E., Zilberfarb, V. & Rabinovitch, M. (1989). Leishmania amazonensis: involvement of cysteine proteinases in the killing of isolated amastigotes by L-leucine methyl ester. Experimental Parasitology 68, 423–31.CrossRefGoogle ScholarPubMed
Alfieri, S. C., Zilberfarb, V. & Rabinovitch, M. (1987). Destruction of Leishmania mexicana amazonensis amastigotes by leucine methyl ester: protection by other amino acid esters. Parasitology 95, 31–41.CrossRefGoogle ScholarPubMed
Antoine, J. C., Jouanne, C. & Ryter, A. (1989). Megasomes as the target of leucine methyl ester in Leishmania amazonensis amastigotes. Parasitology 99, 1–9.CrossRefGoogle ScholarPubMed
Coombs, G. H., Tetley, L., Moss, V. A. & Vickerman, K. (1986). Three dimensional structure of the Leishmania amastigote as revealed by computer-aided reconstruction from serial sections. Parasitology 92, 13–23.CrossRefGoogle ScholarPubMed
Fong, D., Wallach, M., Keithly, J., Meleran, P. W. & Chang, K. P. (1984). Differential expression of mRNAs for α- and β-tubulin during differentiation of the parasitic protozoan Leishmania mexicana. Proceedings of the National Academy of Sciences, USA 81, 5782–6.CrossRefGoogle ScholarPubMed
Hunter, C. A., Macpherson, L. M. & Coombs, G. H. (1989). Antileishmanial activity of L-leucine methyl ester and L-tryptophanamide. In Leishmaniasis, The Current Status and New Strategies for Control (ed. Hart, D. T.), pp. 741–7. New York: Plenum Press.CrossRefGoogle Scholar
Lockwood, B. C., North, M. J., Mallinson, D. J. & Coombs, G. H. (1987). Analysis of Leishmania proteinases reveals developmental changes in species-specific forms and a common 68-kDa activity. FEMS Microbiology Letters 48, 345–50.CrossRefGoogle Scholar
Neal, R. A. (1987). Experimental chemotherapy. In The Leishmaniasis, vol. 2. (ed. Peters, W. & Killick-Kendrick, R), pp. 793–845. London: Academic Press.Google Scholar
Pan, A. A. & Mcmahon-pratt, D. (1988). Monoclonal antibodies specific for the amastigote stage of Leishmania pifanoi. I. Characterization of antigens associated with stage- and species-specific determinants. Journal of Immunology 140, 2406–14.CrossRefGoogle ScholarPubMed
Pupkis, M. F. & Coombs, G. H. (1984). Purification and characterization of proteolytic enzymes of Leishmania mexicana mexicana amastigotes and promastigotes. Journal of General Microbiology 130, 2375–83.Google Scholar
Pupkis, M. F., Tetley, L. & Coombs, G. H. (1986). Leishmania mexicana: amastigote hydrolases in unusual lysosomes. Experimental Parasitology 62, 29–39.CrossRefGoogle ScholarPubMed
Rabinovitch, M. (1989). Leishmanicidal activity of amino acid and peptide esters. Parasitology Today 5, 299–301.CrossRefGoogle ScholarPubMed
Rabinovitch, M. & Zilberfarb, v. (1988). Destruction of intracellular and isolated Leishmania mexicana amazonensis by amino acid amides. Parasitology 96, 289–96.CrossRefGoogle ScholarPubMed
Rabinovitch, M., Zilberfarb, V. & Ramazeilles, C. (1986). Destruction of Leishmania mexicana amazonensis amastigotes within macrophages by lysosomotropic amino acid esters. Journal of Experimental Medicine 163, 520–35.CrossRefGoogle ScholarPubMed
Ramazeilles, C. & Rabinovitch, M. (1989). Leishmania amazonensis: uptake and hydrolysis of 3H-amino acid methyl esters by isolated amastigotes. Experimental Parasitology 68, 135–43.CrossRefGoogle ScholarPubMed
Sacks, D. L. (1989). Metacyclogenesis in Leishmania promastigotes. Experimental Parasitology 68, 135–43.Google Scholar
Spector, T. (1978). Refinement of the Coomassie method of protein quantitation. A simple and linear spectrophotometric assay for 0·5–50 g protein. Analytical Biochemistry 86, 142–6.CrossRefGoogle Scholar
Tetley, L., Hunter, C. A., Coombs, G. H. & Vickerman, K. (1989). Generation of megasomes during the promastigote-amastigote transformation of Leishmania mexicana mexicana in vitro. In Leishmaniasis, The Current Status and New Strategies for Control (ed. Hart, D. T.), pp. 449–455. New York: Plenum Press.CrossRefGoogle Scholar