Role of Candida albicans-Secreted Aspartyl Proteinases (Saps) in Severe Early Childhood Caries

Abstract

Candida albicans is strongly associated with severe early childhood caries (S-ECC). However, the roles of secreted aspartyl proteinases (Saps), an important virulence factor of C. albicans, in the progress of S-ECC are not clear. In our study, the Saps activities were evaluated by the yeast nitrogen base–bovine serum albumi (YNB–BSA) agar plate method and by the MTT method with bovine serum albumin (BSA) as the substrate. Genotypes of C. albicans and gene expression of Sap1–5 were evaluated. The relationships of Saps activities and genotypes with S-ECC were analyzed. The results showed that enzyme activities of Saps in the S-ECC group were significantly higher than those in the caries free (CF) group (p < 0.05). Genotypes A, B and C were detected in the S-ECC group, and genotypes A and C were detected in the CF group. In the genotype A group, Saps activity in the S-ECC group was significantly different from that in the CF group (p < 0.05). The gene expression level of Sap1 in the S-ECC group was significantly higher than that in the CF group (p = 0.001), while Sap4 expression was significantly lower than that in the CF group (p = 0.029). It can be concluded that Sap1–5 are the predominant proteinase genes expressed in C. albicans from dental biofilm and Sap1 may play an important role in the development of S-ECC.

Genotype comparison of Candida albicans isolates from different clinical samples

“…Genotype determinations of C. albicans strains tend to be genetically similar to each other, when originating from similar pop-ulation groups, in relation to the immune condition, anatomic site, or geographical location [9]. Genotypes A, B, and C were also detected in 73 strains sampled from dental biofilms of severe early childhood caries [5]. In another study, genotypes were detected by analysing 151 strains of C. albicans (71 samples from infant patients with cutaneous candidiasis and 61 samples from females with vaginal candidiasis), and no distinctive association was found between genotype and the site of cutaneous infection [7].…”

“…DNA was obtained by lysing the yeast cells at 95°C for 5 min followed by immersing in ice and centrifugation. PCR to detect the genotypes was performed according to the method previously described [4][5] using the primers CA-NT-L (5'-ATAAGG-GAAGTCGGCAAAATAGATCCGTAA-3') and CA-NT-R (5'-CCTTGGCTGTGGTTTC-GCTAGATAGTAGAT-3'). All PCR amplification reactions were performed in 50 μL of distilled water containing 2.0 μL of each primer, 2.0 μL of genomic DNA (5 μg/mL) and one PCR bead (Ready-to-Go PCR beads; Amersham Pharmacia Biotech, Piscataway, NJ, USA).…”

“…The products were analysed using DNA microfluidic chips of Experion Automated Electrophoresis System (Bio-Rad, USA). The genotypes of C. albicans can be divided into 5 groups by the size of DNA amplified fragments (450 bp for group A, 840 bp for group B, 450 and 840 bp for group C, 1080 bp for group D and 1400 bp for group E) [5][6][7]. The results were submitted to a preliminary multiple correspondence analysis (MCA) which had been assessed using XlStat-Ecology 2018.7 version.…”

Phenotypic and genotypic variations in Candida albicans isolates from Romanian patients

“…DNA was obtained by lysing the cells at 95°C for 5 min and by immersing in ice. PCR was performed according to the method previously described [16][17] using the primers CA-NT-L (5'-ATAAGGGAAGTCGGCAAAATAGATC-CGTAA-3') and CA-NT-R (5'-CCTTGGCT-GTGGTTTCGCTAGATAGTAGAT-3').…”

“…According to the PCR products, the genotypes of C. albicans can be classified by the size of DNA amplified into 3 groups: 450 bp for group A, 840 bp for group B, 450 and 840 bp for group C) [17][18][19].…”