Document Detail


Leishmania infection of human skin fibroblasts in vitro: absence of phagolysosomal fusion after induced phagocytosis of promastigotes, and their intracellular transformation.
MedLine Citation:
PMID:  727316     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Cellular interactions between human skin fibroblasts and promastigotes of two leishmanial species were studied in vitro by light and electron microscopy. Fibroblasts were found to become infected by the species with a history of causing mucocutaneous infection, but not by that of the visceral type or Leishmania donovani. Scanning and transmission electron microscopy revealed that promastigotes of the invasive species entered fibroblasts flagellum-end first through pseudopodia-like structures formed on the host cell surface, reminiscent of "induced phagocytosis." Ingested promastigotes became lodged in vacuoles that did not fuse with secondary lysosomes prelabeled with an electron-dense marker for identification. Transformation of promastigotes into amastigotes occurred among those located within host cells and was influenced by the ambient temperature. Intracellular parasite populations gradually decreased during a 3-week period in vitro, although dividing forms were occasionally seen at all incubation temperatures (32--37 degrees C). There was evidence that viable amastigotes were liberated by cytolysis and/or exocytosis of some infected cells. It is postulated that invasion of non-phagocytic cells by promastigotes and their subsequent transformation therein may allow them to escape from the often fatal consequence of direct confrontation with mononuclear phagocytes, and may be a survival mechanism associated with this parasite stage during the early host-parasite interaction in natural infection.
Authors:
K P Chang
Related Documents :
20049986 - Development and ultrastructure of cystoisospora canis nemeséri, 1959 (syn, isospora can...
2499976 - Liver parenchymal cell parasitism in human visceral leishmaniasis.
18944766 - Biotrophic development of sporisorium reilianum f. sp. zeae in vegetative shoot apex of...
19762436 - Influence of type iv pilus retraction on the architecture of the neisseria gonorrhoeae-...
14509576 - Expression of e-cadherin in normal, hyperplastic and neoplastic feline mammary tissue.
20183796 - Absorptive activities of the efferent ducts evaluated by the immunolocalization of aqua...
Publication Detail:
Type:  Comparative Study; In Vitro; Journal Article; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  The American journal of tropical medicine and hygiene     Volume:  27     ISSN:  0002-9637     ISO Abbreviation:  Am. J. Trop. Med. Hyg.     Publication Date:  1978 Nov 
Date Detail:
Created Date:  1979-02-26     Completed Date:  1979-02-26     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0370507     Medline TA:  Am J Trop Med Hyg     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  1084-96     Citation Subset:  AIM; IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Fibroblasts / immunology,  pathology
Humans
Leishmania / parasitology*
Leishmaniasis / immunology*,  pathology
Leishmaniasis, Mucocutaneous / immunology
Leishmaniasis, Visceral / immunology
Phagocytosis*
Skin / immunology*,  pathology
Species Specificity

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Psychogenic impotence and the black man's burden.
Next Document:  Giardiasis in American travelers to Madeira Island, Portugal.