Previous Article | Next Article 
Journal of Clinical Microbiology, May 1999, p. 1376-1380, Vol. 37, No. 5
Department of Bacteriology and Medical
Mycology,
Received 9 December 1998/Returned for modification 30 January
1999/Accepted 17 February 1999
Vaginal isolates of Candida albicans from human
immunodeficiency virus-positive (HIV+) and
HIV Mucosal candidiases are common
opportunistic diseases in human immunodeficiency virus (HIV)-infected
patients (20, 25), but their immunopathogenesis is poorly
understood. The transition of Candida albicans, the most
common agent of mucosal candidiasis (29), from asymptomatic
carriage to invasion of mucosal tissues is associated with lowering of
the number of CD4+ T lymphocytes, perturbation in the
T-helper-type response, and lack of T-cell recognition of
immunodominant Candida antigens (31, 35).
However, in HIV+ subjects there might be a selection of
more virulent C. albicans strains and increasing resistance
to antimycotics (6-8, 26, 33, 34, 37), thus contributing to
the outbreak of the disease, as well as its easily relapsing nature and
treatment failures.
Since the ability to secrete one or more members of the secretory
aspartyl proteinase (Sap) family is a Candida virulence trait (11, 21, 32), we have previously assessed Sap
secretion by Candida isolates from the oral cavities of
subjects at different stages of HIV infection. Strains of C. albicans with particularly high Sap production were much more
frequently isolated from the oral cavities of HIV+ than
HIV In the light of this information, and also because Sap is a potential
target of new anticandidal agents, we have now compared, in vitro and
in vivo, levels of Sap production in HIV+ and
HIV Subjects.
Eighty-six HIV+, nonpregnant,
nondiabetic women attending as outpatients the Clinic of Obstetrics and
Gynecology of the "Università La Sapienza" (Rome, Italy)
during 1996 were consecutively examined for the presence of vaginal
candidiasis. Each case was diagnosed on the basis of fungus isolation,
the presence of the physical signs of a typical vaginal discharge
(clumpy, cottage-cheese-like appearance), and intense vulvovaginal
pruritus, with or without vulvar erythema and dyspareunia
(10). HIV+ women with no symptoms or signs of
vaginitis but with Candida isolation from the vagina were
considered Candida carriers. The criteria for HIV infection
and staging were those routinely adopted (2, 13, 15). The
CD4+ T-cell means (± standard errors [SE]) were 326 (±52) and 443 (±106) for subjects with vaginitis and asymptomatic
subjects, respectively.
Yeast isolation and identification.
Vaginal samples were
taken with cotton-tipped swabs and kept in sterile physiological
saline, before being transferred to the laboratory, where they were
streaked on plates of Sabouraud dextrose agar (BBL, Baltimore, Md.)
with added chloramphenicol (50 µg/ml) and on plates of Mycosel agar
before immersion into enrichment broth. All cultures were incubated for
48 to 72 h at 30°C. All isolates were identified on the basis of
their morphologies and profiles with the API 20C system (Biomerieux,
Marcy l'Etoile, France). Serological analysis done according to the
method of Tsuchiya et al. (36) was also performed as an aid
to the final identification of C. albicans.
0095-1137/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.
High Aspartyl Proteinase Production and Vaginitis
in Human Immunodeficiency Virus-Infected Women
ABSTRACT
Top
Abstract
Introduction
Materials and Methods
Results
Discussion
References
women with or without candidal vaginitis were
examined for secretory aspartyl proteinase (Sap) production in vitro
and in vivo and for the possible correlation of Sap production with
pathology and antimycotic susceptibility in vitro. HIV+
women with candidal vaginitis were infected by strains of C. albicans showing significantly higher levels of Sap, a virulence enzyme, than strains isolated from HIV+, C. albicans carrier subjects and HIV subjects with
vaginitis. The greater production of Sap in vitro was paralleled by
greater amounts of Sap in the vaginal fluids of infected subjects. In
an estrogen-dependent, rat vaginitis model, a strain of C. albicans producing a high level of Sap that was isolated from an
HIV+ woman with vaginitis was more pathogenic than a strain
of C. albicans that was isolated primarily from an
HIV, Candida carrier. In the same model,
pepstatin A, a strong Sap inhibitor, exerted a strong curative effect
on experimental vaginitis. No correlation was found between Sap
production and antimycotic susceptibility, as most of the isolates were
fully susceptible to fluconazole, itraconazole, and other antimycotics,
regardless of their source (subjects infected with strains producing
high or low levels of Sap, subjects with vaginitis or carrier subjects, or subjects with or without HIV). Thus, high Sap production is associated with virulence of C. albicans but not with
fungal resistance to fluconazole in HIV-infected subjects, and Sap is a
potentially new therapeutic target in candidal vaginitis.
INTRODUCTION
Top
Abstract
Introduction
Materials and Methods
Results
Discussion
References
subjects (13, 15, 30). We also showed that
HIV candidal vaginitis patients harbored in their vaginas
C. albicans strains with increased Sap production (1,
10, 12).
subjects with or without vaginitis. In addition, we
assessed with a rat vaginitis model the pathogenicity of a human
vaginal isolate of C. albicans that produces a high level of
Sap and the response of this infection to therapeutic treatment with
pepstatin A, a Sap inhibitor (21). Finally, because of the
reports on the increased resistance to fluconazole of C. albicans strains isolated from HIV+ subjects
(2-5, 18, 23), we also evaluated the susceptibility to
triazole drugs of Candida isolates by an improved,
internationally tested method of antimycotic susceptibility
determination (2a, 28).
MATERIALS AND METHODS
Top
Abstract
Introduction
Materials and Methods
Results
Discussion
References
outpatients, matched for age to the
HIV+ women, who were Candida carriers or
affected by symptomatic candidal vaginitis. All vaginitis subjects were
not under antimycotic therapy or prophylaxis at the moment of fungus isolation.
20°C, transported to the laboratory within 2 h, and kept
frozen until the Sap assay (see below).
Sap detection in vitro and in vaginal fluids.
All isolates
were tested for their ability to grow and produce a clear zone of
hydrolysis in bovine serum albumin (BSA) agar (yeast carbon base
[Difco], 1.17%; yeast extract [BBL], 0.01%; BSA [BDH], 0.2%),
as a measure of Sap activity. The medium was adjusted to pH 5, sterilized by filtration, and added to a stock solution of autoclaved
(2%) agar. Sap activity was scored as follows: when no visible
clarification of the agar around the colony was present, 1+ when a
visible clear zone (1 to 2 mm in diameter) was observed, and 2+ when
agar clarification largely exceeded (by 3 to 5 mm) the margin of colony
(see also references 12 and 13).
Antimycotic susceptibility test. A recently modified, improved method of antimycotic susceptibility assays in vitro, derived from the standardized method of the National Committee for Clinical Laboratory Standards (3, 28), was used throughout this study for the determination of Candida isolate susceptibility to fluconazole and itraconazole (2a). Susceptibility to other antimycotics was determined by the ATB fungus method (Biomerieux).
A stock solution of fluconazole (Pfizer Inc., New York, N.Y.) was prepared in sterile distilled water. A stock solution of itraconazole (Janssens Pharmaceutica, Beerse, Belgium) was prepared in polyethylene glycol 400 by heating the solution at 75°C for 45 min. The yeast isolates were grown on Sabouraud dextrose agar for 48 h at 35°C. The inoculum suspension was prepared by picking five colonies of at least 1 mm in diameter and suspending them in 5 ml of sterile distilled water. The cell density of the suspension was adjusted spectrophotometrically to a final transmission of 85% at 530 nm. The working suspension was made with a 1:50 dilution in sterile distilled water followed by a 1:20 dilution in medium to obtain a 2× final suspension. Inoculum sizes were confirmed by the enumeration of CFU on Sabouraud dextrose agar. The medium for susceptibility testing was RPMI 1640 (American Biorganics, Inc., Niagara Falls, N.J.) to which L-glutamine had been added; this medium was buffered at pH 7.0 with 0.165 M morpholinepropanesulfonic acid. Testing was performed in sterile, flat-bottom 96-well microtiter plates. Drugs were prepared at 10 times the strength of the final concentration, and these mother solutions were diluted 1:5 with RPMI 1640 to obtain two times the final concentrations. Volumes of 50 µl of the 2× drug dilutions were dispensed into wells; two wells of each row served as growth and sterility controls. The microtiter plates were stored at70°C until
use. The day of the test, 50 µl of the yeast suspension was added to
each well.
The microtiter plates were incubated at 35°C, and optical densities
were read at 24 and 48 h with the aid of a reading mirror after
the growth in each well was shaken and compared with that of the growth
control (drug-free) well.
A numerical score which ranged from 0 to 4 was given to each well by
using the following scale: 0, optically clear; 1, slightly hazy; 2, prominent decrease in turbidity; 3, slight reduction in turbidity; and
4, no reduction in turbidity. The MIC was defined as the lowest drug
concentration at which a score of 2 (prominent decrease in turbidity)
was observed (2a, 3, 28).
Experimental rat vaginitis and pepstatin A activity.
Oophorectomized, female Wistar rats (80 to 100 g; Charles River
Breeding Laboratories, Calco, Italy) were injected subcutaneously with
0.5 mg of estradiol benzoate (Benzatrone; Samil, Rome, Italy). Six days
after the first estradiol treatment, the animals were inoculated
intravaginally with 107 yeast cells in 0.1 ml of each
strain tested. The inoculum was dispensed into the vaginal cavity
through a syringe equipped with a multipurpose calibrated tip
(Combitip; Pool Bioanalysis International [PBI] Milan, Italy). The
inoculated cells had been previously grown in YEDP at 28°C on a
gyrotory shaker (200 rpm), harvested by centrifugation
(3,000 × g), washed, counted in a hemacytometer, and
suspended to the required number in 0.86% NaCl. The fungal cells in
the vaginal cavity were counted by culturing 1-µl samples of vaginal
fluid (taken from each animal with a calibrated plastic loop
[Disponoic; PBI]) on Sabouraud dextrose agar containing
chloramphenicol at 28°C for 72 h. One vaginal sample per rat was
evaluated, and a rat was considered infected when at least 1 CFU was
present, i.e., 
103 CFU/ml of vaginal fluid were present.
Statistics.
Differences were assessed for statistical
significance by Student's t test, the 
2
method, or Fisher's exact method, as appropriate. P values
of <0.05 (two-tailed) were considered significant.
| |
RESULTS |
|---|
|
Top
Abstract
Introduction
Materials and Methods
Results
Discussion
References
|
|---|
Prevalence and distribution of Candida species isolated
from HIV+ and HIV women.
Candida
spp. were isolated from the vaginas of 28 of 86 and 67 of 136 HIV+ and HIV women, respectively. Table
1 shows the species distribution and
their relative proportions in both vaginitis patients and carriers who
were either HIV+ or HIV. C. albicans accounted for almost all yeast isolations from
HIV+ women who either had vaginitis or were carriers. In
contrast, many other species of Candida and even
Saccharomyces cerevisiae were isolated in remarkable
proportions from HIV women. In particular, the isolation
of non-albicans species of Candida was
significantly more frequent from HIV carriers than from
symptomatic women, and Candida glabrata was isolated twice
as frequently as C. albicans from the vaginas of HIV subjects. Overall, the prevalence of C. albicans in HIV+ women was 30.2% compared with the
19.8% prevalence in HIV subjects, and 92.8% of the
isolates from HIV+ women compared with 40.2% of the
isolates from HIV women were C. albicans
(P < 0.01, 2 method).
|
Sap secretion in vitro.
Sap secretion in vitro was assessed by
measuring the proteolytic activity on BSA agar and by detecting Sap
antigen in supernatants in BSA broth by ELISA (16, 20).
Regardless of their source, all isolates of C. albicans
expressed an enzymatically active Sap and secreted the relevant antigen
in the culture medium (Table 2). However,
the isolates from HIV+ women with symptomatic vaginitis
produced the greatest amount of enzyme detectable by ELISA and all the
tested strains exhibited the highest proteolytic potential on BSA agar.
Compared to HIV subjects with vaginitis, HIV+
women with vaginitis were infected by significantly more proteolytic strains and their Sap antigen production was significantly higher. In
contrast, levels of Sap production by isolates from carriers were
relatively low and not significantly different between HIV+
and HIV subjects (Table 2).
|
Sap secretion in vivo.
The amounts of Sap in the vaginal
fluids of subjects in the various categories were also measured. Sap
was present in the vaginal fluids of all HIV+ and
HIV women from whose vaginas C. albicans was
isolated, while it was under the detection limit (<2 ng/ml) in all
other subjects, from whom either no yeast was isolated or a yeast
species other than C. albicans was isolated. The enzyme was
more abundant in the vaginal fluids of C. albicans-infected,
HIV+ subjects with vaginitis than in those of
HIV+ Candida carriers (235.5 ± 40.6 versus
73.2 ± 19.3 ng/ml; P < 0.05). Thus, the higher
levels of Sap secretion in the culture supernatants of individual
C. albicans isolates correlated with the increased levels of
Sap detected in the vaginal fluids. There was also a trend for higher
secretion of Sap in the vaginal fluids of HIV+ subjects
with vaginitis than in those of their HIV counterparts,
although the difference did not reach statistical significance (Table
3).
|
Experimental rat vaginitis.
A vaginal isolate of C. albicans from an HIV+ subject (strain CO11) that
produced a high level of Sap was assayed for its vaginopathic potential
in a rat vaginitis model and compared with a strain that produced a
significantly lower level of Sap in vitro, initially isolated from the
vagina of an HIV woman. In these experiments, the effect
of pepstatin A, an inhibitor of Sap activity (21, 32), was
also tested. As shown in Fig. 1, the
high-level-Sap strain CO11 was cleared from the rat vagina significantly more slowly than the low-level-Sap strain. At 3 weeks
postinfection, CO11 strain cells were still present in the vagina at a
high burden whereas the control strain cells had been substantially
eliminated. Pepstatin A greatly accelerated the clearance of the
infection by the high-level-Sap strain CO11 (Fig. 1). This experiment
was repeated, with totally comparable results.
|
) isolated from the vagina of an HIV+ subject with
vaginitis compared to the experimental infection caused by a
low-level-Sap strain (SA-40) from a stock culture collection, initially
isolated from the vagina of an HIV
). The 
symbols indicate results with the rats challenged with the CO11 strain
and cured with pepstatin A, a Sap inhibitor. Each curve represents the
means (± SE) of the Candida CFU of five rats per group. All
rats were still infected on day 15, when the experiment was stopped.
Usually, the rats clear the infection completely in 1 month (see
references Antimycotic susceptibilities of Candida spp. isolates
from the vaginas of HIV+ and HIV women.
Susceptibilities to antimycotic agents of Candida spp.
isolates from the vaginas of HIV+ and HIV
women were also investigated. Nineteen and 18 of the 21 isolates from
HIV+ subjects were susceptible to fluconazole and
itraconazole, respectively. All isolates were also susceptible to
amphothericin B. Four isolates were resistant to flucytosine, 11 were
resistant to miconazole, 5 were resistant to econazole, and 4 were
resistant to ketoconazole. Only 1 of the 22 isolates from
HIV women was resistant to fluconazole and itraconazole.
All isolates were susceptible to amphothericin B. One isolate was
resistant to flucytosine, four isolates were resistant to miconazole,
and all isolates were susceptible to econazole and ketoconazole. There was no correlation between antimycotic resistance and Sap production (data not shown).
| |
DISCUSSION |
|---|
|
Top
Abstract
Introduction
Materials and Methods
Results
Discussion
References
|
|---|
Although the introduction of highly active antiretroviral therapy with HIV protease inhibitors has a significant impact upon the incidence of opportunistic infections in HIV+ patients, mucosal candidiases remain a serious problem in these subjects. There is also some debate about selection, in AIDS patients, of more virulent biotypes of C. albicans with increased potential for adaptation to the mucosal environment. As preliminarily shown elsewhere (13, 15), C. albicans, the most pathogenic species of Candida, is almost invariably isolated from patients with AIDS whereas many other less virulent Candida species may colonize the mucosae of healthy subjects (1, 27, 29). Moreover, mucosal candidiasis in AIDS patients is often difficult to treat and recurrences of the infections are frequent even after appropriate antifungal treatments (4, 8), suggesting an increased potential of C. albicans to attack the debilitated host. Thus, it is likely that C. albicans participates actively in determining the nature of mucosal infection with its own virulence factors.
In the above context, Sap production has been indicated as being one of the most relevant factors of Candida virulence in mucosal diseases (10, 11, 32). In particular, experiments with individual SAP gene knockout mutants demonstrated that the SAP2 gene, which codes for the Sap2 protein, abundantly produced in the vaginal cavity, is essential for the expression of the vaginopathic potential of C. albicans (17). We and others (15, 30) have previously shown that the strains of C. albicans isolated from the oral cavities of HIV+ subjects were strong Sap producers. The results of this paper demonstrate that C. albicans strains with particularly high levels of Sap secretion are significantly more likely to be isolated from HIV+ women with symptomatic vaginitis than from asymptomatic HIV+ women. Interestingly, the higher levels of Sap secreted in vitro by C. albicans isolates had a correlate in increased levels of Sap in the vaginal fluids of HIV+ symptomatic subjects compared to levels of the enzyme detected in HIV+, fungal carriers. This result demonstrates that the high potential of the strains to produce Sap was not a mere characteristic of their in vitro growth but likely resulted from selection of strains that produce high levels of Sap in vivo.
These results parallel our previous findings with strains of C. albicans from oral cavities (17). Altogether, these data support the notion that more virulent strains of C. albicans may indeed by isolated from the mucosae of HIV-infected subjects. Enzymes of the Sap family (in particular, Sap2) are well known for their ability to degrade a number of proteins important in host defense, such as Igs, complement, and cytokines (21, 24, 32). Thus, the selection in AIDS patients of strains that produce high levels of Sap might be relevant for the aggressive potential of C. albicans and contribute to the aggravation of host conditions. Recently, Sap production has also been implicated in the enhancement of Candida virulence following HIV gp160 and gp41 binding to the fungus (19).
That Sap production may be relevant to the vaginopathic potential of C. albicans is also supported by our recent studies with an experimental rat vaginitis model, where anti-Sap antibodies of IgA and IgG isotypes, elicited during a primary vaginal infection, were capable of conferring protection to naive, uninfected rats (14, 16). The finding that the particularly high vaginopathic potential of the isolates from the vaginas of HIV+ subjects that produce high levels of Sap can be strongly inhibited by pepstatin A (21) also suggests that inhibitors of Sap synthesis and/or secretion, such as pepstatin A derivatives or analogues, might potentially be useful for vaginitis treatment.
Our antimycotic susceptibility data, obtained by an improved modification of an internationally standardized method of evaluating the triazole sensitivities of clinical isolates of Candida and Cryptococcus species (28), clearly indicated that resistance to efficacious triazole drugs was of low prevalence in our subjects and had no correlation with possible selection of increased proportions of high-level-Sap isolates. It has been shown that fluconazole-resistant cells are present in the infecting C. albicans population and that selective pressure for overgrowth of these clones is conferred upon the fungal cells by prolonged, repeated cycles of antimycotic treatment. However, no virulence correlates were found in the resistant strains (3, 5, 18, 23). A retrospective examination of clinical charts revealed that the great majority of the study subjects had not been treated other than occasionally with fluconazole for their candidiasis recurrences. However, most of them were treated with other azoles (miconazole and ketoconazole), to which several resistant strains were indeed found. In fact the isolation of fluconazole-resistant strains of C. albicans from AIDS patients is a common phenomenon only after prolonged treatment with the drug (3, 5, 18, 23). This fact is consistent with the suggestion that alternating cycles of treatment with different azoles, rather than using a single azole for prolonged periods, might prevent or retard the emergence of isolates resistant to this class of drugs.
| |
ACKNOWLEDGMENTS |
|---|
This work was supported by the National AIDS Project, Istituto Superiore di Sanità, contract 940/E.
We are grateful to Anna Botzios and Giuseppina Mandarino for help in the preparation of the manuscript.
| |
FOOTNOTES |
|---|
* Corresponding author. Mailing address: Department of Bacteriology and Medical Mycology, Istituto Superiore di Sanità, Viale Regina Elena, 299, 00161 Rome, Italy. Phone: 39.6.49387113. Fax: 39.6.49902934. E-mail: cassone{at}iss.it.
| |
REFERENCES |
|---|
|
Top
Abstract
Introduction
Materials and Methods
Results
Discussion
References
|
|---|
| 1. |
Agatensi, L.,
F. Franchi,
F. Mondello,
R. L. Bevilacqua,
T. Ceddia,
F. De Bernardis, and A. Cassone.
1991.
Vaginopathic and proteolytic Candida species in outpatients attending a gynecology clinic.
J. Clin. Pathol.
44:826-830 |
| 2. | Agresti, M. G., F. De Bernardis, F. Mondello, et al. 1994. Clinical and mycological evaluation of fluconazole in the secondary prophylaxis of esophageal candidiasis in AIDS patients. Eur. J. Epidemiol. 10:17-20[Medline]. |
| 2a. | Barchiesi, F., et al. Submitted for publication. |
| 3. | Barchiesi, F., R. J. Hollis, M. Delpoeta, D. A. McGough, G. Scalise, M. Rinaldi, and M. A. Pfaller. 1995. Transmission of fluconazole-resistant Candida albicans between patients with AIDS and oropharyngeal candidiasis documented by pulsed-field gel electrophoresis. Clin. Infect. Dis. 21:561-564[Medline]. |
| 4. |
Barchiesi, F. A.,
L. Colombo,
D. A. McGough,
A. W. Fothergill, and M. G. Rinaldi.
1994.
In vitro activity of itraconazole against fluconazole-susceptible and -resistant Candida albicans isolates from oral cavities of patients infected with human immunodeficiency virus.
Antimicrob. Agents Chemother.
38:1530-1533 |
| 5. |
Bart-Delabesse, E.,
P. Boiron,
A. Carlotti, and B. Dupont.
1993.
Candida albicans genotyping in studies with patients with AIDS developing resistance to fluconazole.
J. Clin. Microbiol.
31:2933-2937 |
| 6. | Boerlin, P., F. Berlin-Petzold, C. Durussel, M. Addo, J. L. Pagani, J. P. Chave, and J. Bille. 1995. Cluster of oral atypical Candida albicans isolates in a group of human immunodeficiency virus-positive drug users. J. Clin. Microbiol. 33:1129-1135[Abstract]. |
| 7. |
Brawner, D. L., and J. E. Cutler.
1989.
Oral Candida albicans isolates from nonhospitalized normal carriers, immunocompetent hospitalized patients, and immunocompromized patients with or without acquired immunodeficiency syndrome.
J. Clin. Microbiol.
27:1335-1341 |
| 8. |
Bruatto, M.,
V. Vidotto,
G. Marinuzzi,
R. Raiteri, and A. Sinicco.
1991.
Candida albicans biotypes in human immunodeficiency virus type 1-infected patients with oral candidiasis before and after antifungal therapy.
J. Clin. Microbiol.
29:726-730 |
| 9. |
Cantorna, M. T., and E. Balish.
1991.
Role of CD4+ lymphocytes in resistance to mucosal candidiasis.
Infect. Immun.
59:2447-2455 |
| 10. | Cassone, A., F. De Bernardis, F. Mondello, T. Ceddia, and L. Agatensi. 1987. Evidence for a correlation between proteinase secretion and vulvovaginal candidiasis. J. Infect. Dis. 156:777-783[Medline]. |
| 11. | Cutler, J. E. 1991. Putative virulence factors of Candida albicans. Annu. Rev. Microbiol. 45:187-218[Medline]. |
| 12. | De Bernardis, F., L. Agatensi, I. K. Ross, G. W. Emerson, R. Lorenzini, P. A. Sullivan, and A. Cassone. 1990. Evidence for a role for secreted aspartate proteinase of Candida albicans in vulvovaginal candidiasis. J. Infect. Dis. 161:1276-1283[Medline]. |
| 13. | De Bernardis, F., M. Boccanera, L. Rainaldi, C. E. Guerra, I. Quinti, and A. Cassone. 1992. The secretion of aspartyl proteinase, a virulence enzyme, by isolates of Candida albicans from the oral cavity of HIV-infected subjects. Eur. J. Epidemiol. 8:362-367[Medline]. |
| 14. | De Bernardis, F., A. Cassone, J. Sturtevant, and R. A. Calderone. 1995. Expression of Candida albicans SAP1 and SAP2 in experimental vaginitis. Infect. Immun. 63:1887-1892[Abstract]. |
| 15. | De Bernardis, F., P. Chiani, M. Ciccozzi, G. Pellegrini, T. Ceddia, G. D'Offizi, I. Quinti, P. Sullivan, and A. Cassone. 1996. Elevated aspartyl proteinase secretion and experimental pathogenicity of Candida albicans isolates from oral cavities of subjects infected with human immunodeficiency virus. Infect. Immun. 64:466-471[Abstract]. |
| 16. | De Bernardis, F., M. Boccanera, D. Adriani, E. Spreghini, G. Santoni, and A. Cassone. 1997. Protective role of antimannan and anti-aspartyl proteinase antibodies in an experimental model of Candida albicans vaginitis in rats. Infect. Immun. 65:3399-3405[Abstract]. |
| 17. | De Bernardis, F., S. Arancia, L. Morelli, B. Hube, D. Sanglard, W. Schäfer, and A. Cassone. Evidence that members of the secretory aspartyl proteinase gene family (SAP), in particular SAP2, are virulence factors for Candida vaginitis. J. Infect. Dis., in press. |
| 18. |
Fothergill, A. W., and M. G. Rinaldi.
1994.
Variations in fluconazole susceptibility and electrophoretic karyotype among oral isolates of Candida albicans from patients with AIDS and oral candidiasis.
J. Clin. Microbiol.
32:59-64 |
| 19. | Gruber, A., E. Lukasser-Volg, M. Borg-von Zeplin, M. P. Dierich, and R. Wurzner. 1998. Human immunodeficiency virus type 1 gp160 and gp41 binding to Candida albicans selectively enhanced Candida virulence in vitro. J. Infect. Dis. 177:1057-1063[Medline]. |
| 20. | Holmberg, K., and R. D. Meyer. 1986. Fungal infections in patients with AIDS and AIDS-related complex. Scand. J. Infect. Dis. 18:179-185[Medline]. |
| 21. | Hube, B. 1996. Candida albicans secreted aspartyl proteinases. Curr. Top. Med. Mycol. 7:55-69[Medline]. |
| 22. | Iman, N., C. J. Carpenter, H. M. Kenneth, A. Fisher, M. Stein, and S. B. Danforth. 1990. Hierarchical pattern of mucosal candidal infection in HIV-seropositive women. Am. J. Med. 89:142-146[Medline]. |
| 23. |
Johnson, M. E.,
D. W. Warnok,
J. Lukers,
S. R. Porter, and C. Scully.
1995.
Emergence of azole drug resistance in Candida species from HIV-infected patients receiving prolonged fluconazole therapy for oral candidosis.
J. Antimicrob. Chemother.
35:103-114 |
| 24. | Kaminishi, H., H. Miyaguchi, T. Tamaki, N. Suenaga, M. Hisamatsu, I. Mihashi, H. Matsumoto, H. Maeda, and Y. Hagihara. 1995. Degradation of humoral host defense by Candida albicans proteinase. Infect. Immun. 63:984-988[Abstract]. |
| 25. | Klein, R. S., C. A. Harris, C. Butkus Small, B. Moll, M. Lesser, and G. H. Friendland. 1984. Oral candidiasis in high risk patients as the initial manifestation of the acquired immunodeficiency syndrome. N. Engl. J. Med. 311:354-357[Abstract]. |
| 26. | Lupetti, A., G. Guzzi, A. Paladini, K. Swart, M. Campa, and S. Senesi. 1995. Molecular typing of Candida albicans in oral candidiasis: karyotype epidemiology with human immunodeficiency virus-positive patients in comparison with that with healthy carriers. J. Clin. Microbiol. 33:1238-1248[Abstract]. |
| 27. | Mondello, F., A. Guglielminetti, A. Torosantucci, T. Ceddia, L. Agatensi, and A. Cassone. 1986. Yeast species isolated from outpatients with vulvovaginal candidosis attending a gynecological center in Rome. IRCS (Int. Res. Commun. Syst.) Med. Sci. 14:746-747. |
| 28. | National Committee for Clinical Laboratory Standards. 1995. Reference method for broth dilution antifungal susceptibility testing of yeasts. Proposed standard M27-T, vol. 15. National Committee for Clinical Laboratory Standards, Wayne, Pa. |
| 29. | Odds, F. C. 1988. Candida and candidosis. Baillière Tindall, London, United Kingdom. |
| 30. | Ollert, M. W., C. Wende, M. Gorlich, C. G. McMullan-Vogel, M. Borg-Von Zepelin, C. W. Vogel, and H. C. Korting. 1995. Increased expression of Candida albicans secretory proteinase, a putative virulence factor, in isolates from human immunodeficiency virus-positive patients. J. Clin. Microbiol. 33:2543-2549[Abstract]. |
| 31. | Quinti, I., C. Palma, E. C. Guerra, M. J. Gomez, I. Mezzaroma, F. Aiuti, and A. Cassone. 1991. Proliferative and cytotoxic responses to mannoproteins of Candida albicans by peripheral blood lymphocytes of HIV-infected subjects. Clin. Exp. Immunol. 85:485-492[Medline]. |
| 32. | Ruchel, R., F. De Bernardis, T. L. Ray, P. A. Sullivan, and G. T. Cole. 1992. Candida acid proteinases. J. Med. Vet. Mycol. 29(Suppl.):1-9. |
| 33. |
Schmid, J.,
F. C. Odds,
M. J. Wiselka,
G. Nicholson, and D. R. Soll.
1992.
Genetic similarity and maintenance of Candida albicans strains from a group of AIDS patients, demonstrated by DNA fingerprinting.
J. Clin. Microbiol.
30:935-941 |
| 34. |
Sullivan, D.,
D. Bennett,
M. Henman,
P. Harwood,
S. Flint,
F. Mulcahy,
D. Shanley, and D. Coleman.
1993.
Oligonucleotide fingerprinting of isolates of Candida species other than C. albicans and of atypical Candida species from human immunodeficiency virus-positive and AIDS patients.
J. Clin. Microbiol.
31:2124-2133 |
| 35. | Torosantucci, A., C. Bromuro, M. J. Gomez, C. M. Ausiello, F. Urbani, and A. Cassone. 1993. Identification of a 65 kDa mannoprotein constituent as a main target of human cell-mediated immune response to Candida albicans. J. Infect. Dis. 168:427-435[Medline]. |
| 36. | Tsuchiya, T., M. Taguchi, Y. Fukazawa, and T. Shinoda. 1984. Serological characterization. Methods Microbiol. 16:75-76. |
| 37. | Whelan, W. L., D. R. Kirsch, K. J. Kwon-Chung, S. M. Wahl, and P. D. Smith. 1990. Candida albicans in patients with the acquired immunodeficiency syndrome: absence of a novel or hypervirulent strain. J. Infect. Dis. 162:513-518[Medline]. |
Journal of Clinical Microbiology, May 1999, p. 1376-1380, Vol. 37, No. 5
0095-1137/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.
This article has been cited by other articles:
-
Alarco, A.-M., Marcil, A., Chen, J., Suter, B., Thomas, D., Whiteway, M.
(2004). Immune-Deficient Drosophila melanogaster: A Model for the Innate Immune Response to Human Fungal Pathogens. J. Immunol.
172: 5622-5628
[Abstract] [Full Text] -
Naglik, J. R., Challacombe, S. J., Hube, B.
(2003). Candida albicans Secreted Aspartyl Proteinases in Virulence and Pathogenesis. Microbiol. Mol. Biol. Rev.
67: 400-428
[Abstract] [Full Text] -
Schaller, M., Bein, M., Korting, H. C., Baur, S., Hamm, G., Monod, M., Beinhauer, S., Hube, B.
(2003). The Secreted Aspartyl Proteinases Sap1 and Sap2 Cause Tissue Damage in an In Vitro Model of Vaginal Candidiasis Based on Reconstituted Human Vaginal Epithelium. Infect. Immun.
71: 3227-3234
[Abstract] [Full Text] -
PANAGIO, L.A., FELIPE, I., VIDOTTO, M.C., GAZIRI, L.C. J.
(2002). Early membrane exposure of phosphatidylserine followed by late necrosis in murine macrophages induced by Candida albicans from an HIV-infected individual. J Med Microbiol
51: 929-936
[Abstract] [Full Text] -
Santoni, G., Boccanera, M., Adriani, D., Lucciarini, R., Amantini, C., Morrone, S., Cassone, A., De Bernardis, F.
(2002). Immune Cell-Mediated Protection against Vaginal Candidiasis: Evidence for a Major Role of Vaginal CD4+ T Cells and Possible Participation of Other Local Lymphocyte Effectors. Infect. Immun.
70: 4791-4797
[Abstract] [Full Text] -
O’Day, D. M., Head, W. S., Csank, C., Shetlar, D. J., Robinson, R. D., McCollum, G. W., Yang, R., Zhu, T. L., Wang, M. X.
(2000). Differences in Virulence between Two Candida albicans Strains in Experimental Keratitis. IOVS
41: 1116-1121
[Abstract] [Full Text]
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»