Hence, it could be proposed that lipases play a role in the invasion of epithelial tissue in the RHE model. check details On the other hand, the role of lipases in in vitro grown biofilms is not that obvious. It is possible that lipases play a role in nutrient acquisition [8], particularly in the MTP as nutrients become limited after prolonged biofilm growth. Together, our data demonstrate that LIP genes are upregulated in biofilms and extracellular lipases

are produced by sessile C. albicans cells. However, the role and function of these secreted enzymes in C. albicans biofilms remains to be investigated. Gene expression analysis is often used to identify candidate genes involved in C. albicans biofilm formation [21–28]. Previous studies have already examined the global transcriptional response in biofilms grown in Barasertib particular model systems Ro 61-8048 datasheet [26, 44–46]. Similar to the in vitro models previously studied [26, 31, 45], the current study found an overexpression of HWP1 and of several genes belonging to the ALS gene family. In addition, analysis of gene expression in biofilms grown in the MTP and CDC also identified differences from previous studies.

We found that most of the genes belonging to the SAP and LIP gene families are overexpressed in biofilms grown in vitro with or without flow. Recently, a global transcriptional analysis was performed in an vivo venous catheter biofilm model, and ALS1, ALS2 and ALS4 as well as SAP5 and SAP10 were upregulated in this model system [46]. In the present study we found an upregulation of HWP1 and of all ALS and SAP genes (except ALS9) in the in vivo subcutaneous catheter rat model. Similar to the venous catheter model [46], the current study observed an upregulation of several genes belonging to the LIP gene family

and a downregulation of PLB genes. When comparing previously reported gene expression results from in vitro [26, 44, 45] or in vivo [46] biofilm experiments with Exoribonuclease the current data, both similarities and differences in gene expression were observed. This again highlights the fact that the biofilm model system can have a considerable impact on gene expression. Conclusions In conclusion, we can state that HWP1 and most of the genes belonging to the ALS, SAP and LIP gene families are upregulated in C. albicans biofilms in all model systems tested. Future functional analyses of these genes in sessile C. albicans cells will allow us to better understand the exact roles of adhesins and extracellular hydrolytic enzymes in C. albicans biofilms. Comparison of the fold expression of genes encoding potential virulence factors between the two in vitro models, the in vivo model and the RHE model revealed similarities in expression levels for some genes, while for others model-dependent expression levels were observed.