Discrepant Expression Of The HSGs In Biphasic Candida Albicans Strains From OLP And Hyphae Culture&the RNA Extraction Methods

Objective:To study the mechanism and role of morphology switch in Candida albicans from Oral Lichen Planus (OLP) and to investigate the effection factors on hyphal formation of Candida albicans, including suitable broken method for RNA extraction and the types of serum for culture.Method:Mycelium of standard experimental strains and Candida albicans isolated from100patients with41erosive and59non-erosive OLP were cultured with1640plus the different calf serum medium. The rate of hyphal formation was calculated; Total RNA was extracted using modified hot acid phenol method and acid-washed glass beads method from hyphal and yeast cell, with quantitate and integrity of RNA were detected; Expression level of the gene EFG1, a signal regulatory molecules, and the hyphal special genes HGC1, ECE1, HWP1, ALS3in hyphal and yeast cell were analyzed.Results:(1) Infection rate of Candida and Candida albicans:five cases were observed as positived with Candida albicans and one case with Candida tropicale among the59patients with non-erosive OLP, while six cases of Candida albicans, one case of Candida krusei, one case of Candida parapsilosis and one case of Monilia albicans were isolated from41patients with non-erosive OLP. The positive rate of Candidia and Candida albicans in erosive OLP group were both significantly higher than non-erosive OLP group (P＜0.05).(2) Hyphal formation time and culture purity:Candida albicans cultured by RPMI1640+121℃inactivated calf serum got the merit being better than by RPMI1640+56℃inactivated calf serum medium on either time or purity for hyphal formation.(3) RNA extraction of Candida albicans:the hyphae phase, the concentration of hyphae phase was384.74μg/ml and its260/280absorbance ratio was2.11-2.21extracted by modified hot acid phenol method, meanwhile was224.45μg/ml and1.62-1.87respectively when using acid-washed glass beads method. The yeast phase, the concentration was578.88μg/ml and the260/280absorbance ratio was2.07-2.2extracted by modified hot acid phenol method, meanwhile was636.41μg/ml and1.87-2.05respectively when using acid-washed glass beads method.(4) Real-time PCR showed that EFG1, ALS3, ECE1expression had no significant difference in yeast and mycelial phases. HWP1, HGC1were expressed in the hyphae phase, and just litter could be detected in yeast phase.Conclusion:(1) The positive rate of Candidia and Candida albicans in erosive OLP group were both significantly higher than non-erosive OLP group.(2) Candida albicans cultured by RPMI1640+121℃inactivated calf serum got the merit being better than by RPMI1640+56℃inactivated calf serum medium on either time or purity for hyphal formation.(3) Modified hot acid phenol method is proper for RNA extraction from Candida albicans hyphae, while pickling glass beads method is proper for Candida albicans RNA from yeast phase.(4) HWP1, HGC1may be necessarily essential genes for mycelium formation within the limitation of this research.