Project description:Candida albicans is exposed to a different host environment during oropharyngeal candidiasis (OPC) compared to hematogenously disseminated candidiasis. Thus, different virulence factors may be active during these two types of infection. However,little is known about the C. albicans genes that are required for the initiation and maintenance of OPC. To identify potential virulence factors relevant to this disease, we determined the transcriptional response of C. albicans to oral epithelial cells in vitro. Keywords: cell interaction Two different Candida albicans strains, CAI4-URA and a clinical isolate 7392, were used to identify the transcriptional response of C. albicans to oral epithelial cells. The strains were incubated with either the FaDu oral epithelial cell line or bare plastic for 45, 90, and 180 min. C. albicans RNA was extracted and the transcriptional profile of these organisms was analyzed using the C. albicans oligonucleotide microarray. The transcriptional response to Fadu cells was compared to that to bare plastic as a control condition. Each time point contains six biological replicates, three of which are from each C. albicans strain.
Project description:Candida albicans is exposed to a different host environment during oropharyngeal candidiasis (OPC) compared to hematogenously disseminated candidiasis. Thus, different virulence factors may be active during these two types of infection. However,little is known about the C. albicans genes that are required for the initiation and maintenance of OPC. To identify potential virulence factors relevant to this disease, we determined the transcriptional response of C. albicans to oral epithelial cells in vitro. Keywords: cell interaction
Project description:This experiment was to look at the change in gene expression in oral epithelial cells infected for 6 h or 24 h with Candida albicans. The intent was to determine what changes were driven by early and late recognition of wild-type. invasive Candida albicans
Project description:Iron sequestration by host iron-binding proteins is an important mechanism of resistance to microbial infections. Inside oral epithelial cells, iron is stored within the ferritin, and is therefore usually not accessible to pathogenic microbes. We observed that the ferritin concentration within oral epithelial cells was directly related to their susceptibility to damage by the human pathogenic fungus Candida albicans. Thus, we hypothesized that host ferritin may be used as an iron source by this organism. A screen of C. albicans mutants lacking components of each of the three iron acquisition systems revealed that only the reductive pathway is involved in iron utilization from ferritin by this organism. Transcriptional profiling of wild-type and hyphal-defective C. albicans strains suggested that the C. albicans invasin-like protein Als3 plays a role in ferritin binding.
Project description:The effects of Candida albicans on the metastatic activity of oral squamous cell carcinoma was observed in vitro and in vivo. In the in vitro experimental setup HO-1-N-1 and HSC-2 human oral squamous cell carcinoma cell lines were treated with zymosan, heat-killed Candida albicans, heat-killed C. parapsilosis, live C. albicans and live C. parapsilosis. Whole transcriptomics was performed of the human tumor cells. In the in vivo experiment human HSC-2 tumor cells were injected to the tongue of mice. Whole transcriptomic analysis was performed of the human HSC-2 derived tumor cells comparing control tumor and oral candidiasis treated tumor.
Project description:Recent studies have shown that the transcriptional landscape of the pleiomorphic fungus Candida albicans is highly dependent upon growth conditions. Here using a dual RNA-seq approach we identified 299 C. albicans and 72 Streptococcus gordonii genes that were either up- or down-regulated specifically as a result of co-culturing these human oral cavity microorganisms. Seventy five C. albicans genes involved in responses to chemical stimuli, regulation, homeostasis, protein modification and cell cycle were statistically (P ≤0.05) upregulated, while 36 genes mainly involved in transport and translation were down-regulated. Upregulation of filamentation-associated TEC1 and FGR42 genes, and of ALS1 adhesin gene, concurred with previous evidence that the C. albicans yeast to hypha transition is promoted by S. gordonii. Increased expression of genes required for arginine biosynthesis in C. albicans was potentially indicative of a novel oxidative stress response. The transcriptional response of S. gordonii to C. albicans was less dramatic, with only eight S. gordonii genes significantly (P ≤0.05) up-regulated ≥ twofold (glpK, rplO, celB, rplN, rplB, rpsE, ciaR, and gat). The expression patterns suggest that signals from S. gordonii cause a positive filamentation response in C. albicans, while S. gordonii appears to be transcriptionally less influenced by C. albicans. Five Samples; Sample 1 - Candida albicans cells grown in hypha inducing conditions for two hours; Sample 2 - Candida albicans cells grown in hypha-inducing conditions for two hours before co-culture with Streptococcus gordonii cells for one hour in a 2:1 rato; Sample 3 - Candida albicans cells grown in hypha-inducing conditions for two hours before culture in Streptococcus gordonii media for one hour; Sample 4 - Candida albicans cells grown in hypha inducing conditions for two hours, filtered to remove Candida albicans cells and media added to Streptococcus gordonii cells for one hour; Sample 5 - Streptococcus gordonii cells alone for one hour. All samples extracted and sequenced in biological triplicate using Illumina HiSeq2500. Samples 1, 2 and 3 aligned to the reference genome for Candida albicans and Samples 2, 4 and 5 aligned to the reference genome for Streptococcus gordonii.
Project description:The opportunistic human pathogens, Candida albicans and Candida dubliniensis, are closely related species displaying large differences in virulence, but the reasons for these differences are elusive. Microarray-based comparative analysis of global gene expression in the two species incubated on reconstituted human oral epithelium (RHE) was used to identify specific and common changes in gene expression and find novel C. albicans virulence genes
Project description:Candida albicans and Candida dubliniensis are closely related species displaying differences in virulence and genome content, therefore providing potential opportunities to identify novel C. albicans virulence genes. C. albicans gene arrays were used for comparative analysis of global gene expression in the two species in reconstituted human oral epithelium (RHE). C. albicans (SC5314) showed upregulation of hypha-specific and virulence genes within 30 min postinoculation, coinciding with rapid induction of filamentation and increased RHE damage. C. dubliniensis (CD36) showed no detectable upregulation of hypha-specific genes, grew as yeast, and caused limited RHE damage. Several genes absent or highly divergent in C. dubliniensis were upregulated in C. albicans. One such gene, SFL2 (orf19.3969), encoding a putative heat shock factor, was deleted in C. albicans. ÎÎsfl2 cells failed to filament under a range of hypha-inducing conditions and exhibited greatly reduced RHE damage, reversed by reintroduction of SFL2 into the ÎÎsfl2 strain. Moreover, SFL2 overexpression in C. albicans triggered hyphal morphogenesis. Although SFL2 deletion had no apparent effect on host survival in the murine model of systemic infection, ÎÎsfl2 strain-infected kidney tissues contained only yeast cells. These results suggest a role for SFL2 in morphogenesis and an indirect role in C. albicans pathogenesis in epithelial tissues. Global gene expression in Candida albicans SC5314 or Candida dubliniensis CD36 on reconstituted human oral epithelium (RHE) 30 min postinoculation. Gene expression on RHE was compared to gene expression in cells used as inoculum (0 min). Performed in three biological replicates with dye swaps across the biological replicates. Gene expression of Candida cells on RHE was normalized to gene expression in reference control (0 min); log2 ratios were calculated by dividing spot intensity of experimental by that of the reference control.