Most cited article - PubMed ID 16475500
Distribution of secreted aspartyl proteinases using a polymerase chain reaction assay with SAP specific primers in Candida albicans isolates
Fungal infections constitute a serious clinical problem in the group of patients receiving total parenteral nutrition. The majority of species isolated from infections of the total parenteral nutrition patients belong to Candida genus. The most important factors of Candida spp. virulence are the phenomenon of "phenotypic switching," adhesins, dimorphism of fungal cells and the secretion of hydrolytic enzymes such as proteinases and lipases, including aspartyl proteinases. We determined the proteolytic activity of yeast-like fungal strains cultured from the clinical materials of patients receiving total parenteral nutrition and detected genes encoding aspartyl proteinases in predominant species Candida glabrata--YPS2, YPS4, and YPS6, and Candida albicans--SAP1-3, SAP4, SAP5, and SAP6. C. albicans released proteinases on the various activity levels. All C. glabrata strains obtained from the clinical materials of examined and control groups exhibited secretion of the proteinases. All 13 isolates of C. albicans possessed genes SAP1-3. Gene SAP4 was detected in genome of 11 C. albicans strains, SAP5 in 6, and SAP6 in 11. Twenty-six among 31 of C. glabrata isolates contained YPS2 gene, 21 the YPS4 gene, and 28 the YPS6 gene. We observed that clinical isolates of C. albicans and C. glabrata differed in SAPs and YPSs gene profiles, respectively, and displayed differentiated proteolytic activity. We suppose that different sets of aspartyl proteinases genes as well as various proteinase-activity levels would have the influence on strains virulence.
- MeSH
- Candida albicans enzymology genetics isolation & purification MeSH
- Candida glabrata enzymology genetics isolation & purification MeSH
- Virulence Factors genetics metabolism MeSH
- Genome, Fungal MeSH
- Genes, Fungal MeSH
- Candidiasis microbiology MeSH
- Humans MeSH
- Parenteral Nutrition, Total adverse effects MeSH
- Peptide Hydrolases genetics metabolism MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Virulence Factors MeSH
- Peptide Hydrolases MeSH
Candidiases, infections caused by germination forms of the Candida fungus, represent a heterogeneous group of diseases from systemic infection, through mucocutaneous form, to vulvovaginal form. Although caused by one organism, each form is controlled by distinct host immune mechanisms. Phagocytosis by polymorphonuclears and macrophages is generally accepted as the host immune mechanism for Candida elimination. Phagocytes require proinflammatory cytokine stimulation which could be harmful and must be regulated during the course of infection by the activity of CD8+ and CD4+ T cells. In the vaginal tissue the phagocytes are inefficient and inflammation is generally an unwanted reaction because it could damage mucosal tissue and break the tolerance to common vagina antigens including the otherwise saprophyting Candida yeast. Recurrent form of vulvovaginal candidiasis is probably associated with breaking of such tolerance. Beside the phagocytosis, specific antibodies, complement, and mucosal epithelial cell comprise Candida eliminating immune mechanisms. They are regulated by CD4+ and CD8+ T cells which produce cytokines IL-12, IFN-gamma, IL-10, TGF-beta, etc. as the response to signals from dendritic cells specialized to sense actual Candida morphotypes. During the course of Candida infection proinflammatory signals (if initially necessary) are replaced successively by antiinflammatory signals. This balance is absolutely distinct during each candidiasis form and it is crucial to describe and understand the basic principles before designing new therapeutic and/or preventive approaches.
- MeSH
- Antifungal Agents therapeutic use MeSH
- Immunity, Cellular MeSH
- Candida classification immunology pathogenicity MeSH
- Phagocytosis MeSH
- Candidiasis drug therapy immunology MeSH
- Humans MeSH
- Carrier State immunology MeSH
- Immunity, Innate immunology MeSH
- T-Lymphocytes immunology MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Review MeSH
- Names of Substances
- Antifungal Agents MeSH
The ability of C. parapsilosis (an important cause of nosocomial infections) to produce biofilm was evaluated in 32 bloodstream isolates and 85 strains isolated from skin. The biofilm formation was found in 19 (59%) blood isolates and only in 33 (39%) isolates from skin. The antifungal susceptibility was assessed for amphotericin B, itraconazole and voriconazole in planktonic and biofilm form of the 19 biofilm-positive bloodstream strains by broth microdilution method according to NCCLS standards. The method was modified by the use of resazurin as a colorimetric indicator of the metabolically active cells which makes the determination of the effect of antifungal agents easier. Biofilm forms of all strains were more resistant than their planktonic form.
- MeSH
- Antifungal Agents pharmacology MeSH
- Biofilms drug effects MeSH
- Candida drug effects pathogenicity MeSH
- Drug Resistance, Fungal drug effects MeSH
- Fungemia drug therapy MeSH
- Cross Infection microbiology MeSH
- Colorimetry MeSH
- Humans MeSH
- Microbial Sensitivity Tests methods MeSH
- Microbiological Techniques MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Antifungal Agents MeSH