Anin vitroassay to study the transcriptional response during adherence ofCandida albicansto different human epithelia

Abstract

Adhesion to mammalian epithelia is one of the prerequisites that are essential to accomplish pathogenesis of Candida albicans in the mammalian host. In this context C. albicans is able to adhere to a plethora of different cell types providing different microenvironments for colonization. To study the response of C. albicans adhering to different surfaces on the transcriptional level we have established an in vitro adhesion assay exploiting confluent monolayers of the human colorectal carcinoma cell line Caco-2 or epidermoid vulvo-vaginal A-431 cells. Candida albicans very efficiently adheres to these epithelia growing as hyphae. Using whole-genome DNA microarrays comprising probes for almost 7000 predicted ORFs we found that transcriptional profiles of C. albicans adhering to Caco-2 or to A-431 cells, although very similar, still significantly differ from those of Candida cells adhering to plastic surfaces. Differences became even more obvious when comparing C. albicans cells either growing in an adherent manner or in suspension culture. Correspondingly, we found for several cell surface genes, including PRA1, PGA23, PGA7 and HWP1, an adhesion-dependent induction of transcription. Obviously, C. albicans is able to respond specifically to very subtle differences in the environment during adhesion to various growth substrates.

Transcriptional Responses of Candida albicans to Epithelial and Endothelial Cells

“…To our knowledge, the transcriptional response of C. albicans to endothelial cells has not been determined previously. However, two other groups of investigators have studied the response of this organism to contact with vaginal, cervical, and intestinal epithelial cell lines as compared to polystyrene (60,65). Both groups found that contact with epithelial cells caused only a two-to fourfold change in C. albicans gene transcript levels.…”

Decreased expression of 14-3-3 inParacoccidioides brasiliensisconfirms its involvement in fungal pathogenesis

“…The ability to adhere is a biological phenomenon that is widely distributed and shared by many pathogens, enabling the colonization of their respective habitats. 15,16 Some adhesins have been described for P. brasiliensis, such as gp43, 17,18 glyceraldehyde-3-phosphate dehydrogenase, 19 triose phosphate isomerase, 20 enolase, 21,22 a 32-Kda hydrolase, 23,24 malate synthase, 25 isocitrate lyase 26 and the 14-3-3 protein (30 KDa) 27,28 ; this last adhesin is the focus of the present study.…”

Biofilm formation and adhesive/invasive properties of Candida dubliniensis in comparison with Candida albicans

“…A quantitative adhesion assay and an investigation of adhesion kinetics was performed in polystyrene 24-well plates (ThinCert-24well-Multiwell-Platte, Greiner Bio-one) with 5 selected time points (0, 30, 60, 120, 240 min; time point 0 min was used as the background control), according to the published protocol of Sohn et al [23]. For this experiment, a polystyrene plastic surface and RHE were used as described by Dieterich et al [14] with the minor modifications reported by Sohn & Rupp [25].…”

“…Cells were cultivated at 37°C under 5% CO 2 and at saturated humidity up to 80% confluence. Cell cultures were then split 1:5 using standard methods [23,24] and distributed into the 24-well plates for the adhesion assay, as well as plating onto collagen-coated surfaces for the adhesion assay and invasion experiment, as described below.…”