Interaction of Rhodococcus equi with phagocytic cells from R. equi-exposed and non-exposed foals
The interaction of Rhodococcus equi with alveolar macrophages from adult horses, foals experimentally exposed to R. equi (sensitized foals) and non-exposed foals was studied using in vitro bactericidal assays, cytochemical staining and transmission electron microscopy. It was demonstrated that R. eq...
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Published in | Veterinary microbiology Vol. 14; no. 3; pp. 307 - 320 |
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Main Authors | , |
Format | Journal Article |
Language | English |
Published |
Netherlands
Elsevier B.V
01.08.1987
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Subjects | |
Online Access | Get full text |
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Summary: | The interaction of
Rhodococcus equi with alveolar macrophages from adult horses, foals experimentally exposed to
R. equi (sensitized foals) and non-exposed foals was studied using in vitro bactericidal assays, cytochemical staining and transmission electron microscopy. It was demonstrated that
R. equi is a facultative intracellular parasite, able to survive and multiply within the alveolar macrophages of the host by interfering with phagosome-lysosome fusion. Opsonization of
R. equi with antibody against capsular components was associated with increased phagosome-lysosome fusion and significantly enhanced (
P<0.05) killing of the organism by alveolar macrophages from non-exposed foals.
Macrophages from non-exposed foals were able to ingest the non-opsonized organism, but unable to kill > 65% of the infective dose by 6 h post-exposure. Alveolar macrophages from sensitized foals behaved as adult macrophages, able to kill > 95% of the infective dose by 6 h. Lymphocyte factors, derived by in vitro incubation of sensitized peripheral blood lymphocytes with
R. equi surface antigens, enhanced macrophage bactericidal activity. Macrophages from non-exposed foals incubated in the presence of the lymphocyte factors had a 50% increase in killing of
R. equi, while sensitized macrophages incubated with lymphocyte factors had a > 100% increase in killing capacity. |
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Bibliography: | ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 ObjectType-Article-1 ObjectType-Feature-2 |
ISSN: | 0378-1135 1873-2542 |
DOI: | 10.1016/0378-1135(87)90118-0 |