Alternation of HWP1 and PLB1 mRNA Expression Level in Progression of Candida albicans in Different Anatomical Sites

Candida albicans can cause oral, vaginal, and cutaneous infections, as well as systemic candidiasis. It has been recently documented that molecular factors play significant roles in the pathogenesis of Candida albicans in various anatomical sites of the host.

The present study was designed to answer the hypothesis of whether PLB1 and HWP1 mRNA expression patterns are related to the progression of infection in different anatomical sites of the body.

The experimental study was performed on 120 clinical isolates of C. albicans obtained from various sites of non-immune-compromised and immune-compromised patients. Initially, all samples were cultured on Sabouraud-dextrose agar and then CHROM agar Candida medium to isolate and obtain a pure colony of yeasts. Quantitative real-time PCR was carried out for the quantitative evaluation of HWP1 and PLB1 mRNA expression in all clinical samples. The frequency of the PLB1 and HWP1 genes among C. albicans strains isolated from four clinical sites was analyzed using Fisher’s exact test with a significance threshold of P < 0.05. Finally, data obtained from real-time PCR was interpreted using the comparative Ct method (∆∆Ct) by REST© software.

The HWP1 gene was detected at a higher frequency than the PLB1 gene in C. albicans strains. The HWP1 mRNA expression level of clinical samples was upregulated by 70, 83.3, 43.3, and 33.3% in four sites (oral, vaginal, BAL, and cutaneous sites), respectively. The PLB1 mRNA expression level of all samples was upregulated by 46.7, 53.3, 40, and 3.3% (P < 0.001) in four sites compared to the control group.

The PLB1 and HWP1 genes were expressed predominantly in mucosal (oral, vaginal, and BAL) specimens. This clearly shows that the expression pattern of these candidate genes depends on the organ localization. Furthermore, the presence of samples with no expression of HWP1 and PLB1 genes mRNA confirmed the recent hypothesis that there is a meaningful relationship between the higher expression level of candidate genes mRNA and the presence of infections in a specific site of the body. However, more studies are required on larger samples to characterize the exact molecular mechanism of candidate genes involved in the severity of symptoms, as well as their contribution to the site of infection.