Histochemical and Immunochemical Study of the Fate of <i>Candida albicans</i> Inside Human Neutrophil Phagolysosomes

G, Marquis; Garzón, S.; Montplaisir, S; Strykowski, H; Benhamou, Nicole

doi:10.1002/jlb.50.6.587

Cited by 18 publications

(7 citation statements)

References 41 publications

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“…Pathogenic microbes are able to persist intracellularly in phagocytes (Russel, 1995). As shown previously, engulfed Candida are not digested completely (Marquis et al ., 1991). Obviously, one part of the ingested C .…”

Section: Discussionsupporting

confidence: 65%

The expression of the secreted aspartyl proteinases Sap4 to Sap6 from Candida albicans in murine macrophages

Zepelin

Beggah²,

Boggian³

et al. 1998

Molecular Microbiology

166

171

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SummaryMedically important yeasts of the genus Candida secrete aspartyl proteinases (Sap), which are of particular interest as virulence factors. Six closely related gene sequences, SAP1 to SAP6, for secreted proteinases are present in Candida albicans. The methylotrophic yeast Pichia pastoris was chosen as an expression system for preparing substantial amounts of each Sap isoenzyme. Interestingly, Sap4, Sap5 and Sap6, which have not yet been detected in C. albicans cultures in vitro, were produced as active recombinant enzymes. Different Sap polyclonal antibodies were raised in rabbits and tested before further application by enzyme-linked immunosorbent assay (ELISA) against each recombinant Sap. Two antisera recognized only Sap4 to Sap6. Using these antisera, together with sap null mutants obtained by targeted mutagenesis, we could demonstrate a high production of Sap4, Sap5 and Sap6 by C. albicans cells after phagocytosis by murine peritoneal macrophages. Furthermore, a ⌬sap4,5,6 null mutant was killed 53% more effectively after contact with macrophages than the wild-type strain. These results support a role for Sap4 to Sap6 in pathogenicity.

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Section: Discussionsupporting

confidence: 65%

The expression of the secreted aspartyl proteinases Sap4 to Sap6 from Candida albicans in murine macrophages

Zepelin

Beggah²,

Boggian³

et al. 1998

Molecular Microbiology

166

171

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“…5a, lysozyme had no effect on adherence. Lysozyme was tested because it had been shown to be fungicidal to Candida albicans by a direct effect on the yeast cell wall [7]. No such effect, manifested by a change in adherence, was observed after treatment of strain 52817.…”

Section: Resultsmentioning

confidence: 99%

Comparisons betweenin vitroglial cell adherence and internalization of non-encapsulated and encapsulated strains ofCryptococcus neoformans

Merkel

Scofield

1994

Med Mycol

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The adherence of non-encapsulated and encapsulated strains of Cryptococcus neoformans to rat glial cells in culture was compared. Like the encapsulated strain, the adherence of the unencapsulated strain was affected by the yeast culture age and growth temperature. Yeasts grown to late stationary phase at 37°C were the most adherent. Neither encapsulated nor non-encapsulated strains adhered to glial monolayers when the experiments were conducted at 5°C, indicating that metabolically active mammalian cells were required for yeast adherence. Additionally, the non-encapsulated strain was consistently three times more adherent than the encapsulated strain, suggesting that the non-encapsulated strain either had more adhesins or more adhesins were exposed. Electron microscope studies indicated that both strains were internalized by glial cells, an event previously not reported for this mammalian cell type. The same carbohydrates (N-acetyl-Dglucosamine, sucrose and inositol) that inhibited adherence of the encapsulated strain the most, also inhibited adherence of the non-encapsulated strain, again indicating similar adhesin mechanisms. Both encapsulated and non-encapsulated strains were made non-adherent by treatment with pronase, papain, trypsin and amylase. Immobilized amylase appeared to remove an adhesin fragment that bound to glial cells and inhibited the adherence of intact cryptococi.Cryptococcus neoformans is a frequent cause of pulmonary and/or disseminated infection in individuals with AIDS and other immunocompromising diseases [1-3, 6, 12, 13]. In normal individuals pulmonary cryptococcosis may develop following inhalation of yeast aerosols. In most cases this form is asymptomatic, or the symptoms are mild and resolve quickly. In immunocompromised individuals, however, cryptococcosis typically involves dissemination to the central nervous system. Indeed, cryptococcal meningitis is the most common form of cryptococcosis seen in patients with AIDS [8].Although the adherence of many pathogenic microbes to host tissues is now considered to be an important virulence factor associated with colonization and pathogenesis [5], the adherence of C. neoformans to cells derived from typical sites of in vivo infection (e.g. the lungs and central nervous system) has not been extensively examined. In an attempt to understand the role that host cell adherence plays in the pathogenesis of C. neoformans, we have been studying the interactions between cryptococci and potential target tissues. Our interests have specifically focused on certain environmental factors that modulate cryptococcal adherence to cells in culture. In our first report on this subject we demonstrated that yeast culture age and growth temperature both influenced the extent of cryptococcal adherence to lung epithelial cells without altering yeast capsule size [9]. We additionally showed that treating the yeasts with trypsin made the yeasts non-adherent, implying that a protein-containing surface

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“…A number of studies indicate that both peripheral blood monocytes and neutrophils are important components of host defense once C. albicans has entered the bloodstream [6][7][8][9]. Monocytes are known to phagocytize and degrade C. albicans and are likely more efficient than polymorphonuclear leukocytes in killing the organism [8][9][10].…”

Section: Introductionmentioning

confidence: 99%

Candida albicans induces the release of inflammatory mediators from human peripheral blood monocytes

Castro¹,

Bjoraker²,

Rohrbach

et al. 1996

Inflammation

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Candida albicans (C. albicans) is a major nosocomial pathogen. We examined arachidonic acid (AA) and cytokine production by monocytes stimulated with C. albicans. [14C]-AA labeled monocytes released 8.9 +/- 2.3% of the incorporated AA following stimulation with live C. albicans (C. albicans: monocyte of 16:1) (P = 0.0002). Prior studies indicate that soluble alpha-mannans and beta-glucans antagonize mannose and beta-glucan receptors, respectively. Preincubation of monocytes with alpha-mannan (100 micrograms/ml) caused 45.8 +/- 5.7% inhibition of [14C]-AA release, whereas beta-glucan (100 micrograms/ml) yielded 43.7 +/- 6.0% inhibition (P < 0.05 for each compared to control). Additionally, monocytes stimulated with C. albicans also released interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF alpha), interleukin-6 (IL-6) and interleukin-8 (IL-8). However, alpha-mannan or beta-glucan failed to inhibit IL-1 beta release. These data indicate that C. albicans induces monocytes to release AA and inflammatory cytokines. Furthermore, AA, but not cytokine liberation, is partially mediated by alpha-mannan and beta-glucan components of the fungus.

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Histochemical and Immunochemical Study of the Fate of Candida albicans Inside Human Neutrophil Phagolysosomes

Cited by 18 publications

References 41 publications

The expression of the secreted aspartyl proteinases Sap4 to Sap6 from Candida albicans in murine macrophages

The expression of the secreted aspartyl proteinases Sap4 to Sap6 from Candida albicans in murine macrophages

Comparisons betweenin vitroglial cell adherence and internalization of non-encapsulated and encapsulated strains ofCryptococcus neoformans

Candida albicans induces the release of inflammatory mediators from human peripheral blood monocytes

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