Assessment of Surface Markers Derived from Human Periodontal Ligament Stem Cells: An In Vitro Study

Objectives: Periodontal tissue regeneration for treatment of periodontal disease has not yet been mastered in tissue engineering. Stem cells, scaffold, and growth factors are the three main basic components of tissue engineering. Periodontal ligament (PDL) contains stem cells; however, the number, potency and features of these cells have not yet been understood. This study aimed to isolate and characterize the properties of PDL stem cells. Materials and Methods: In this experimental study, samples were isolated from the PDL of extracted teeth of five patients and then stained immunohistochemically for detection of cell surface markers. Cells were then examined by immuno-flow cytometry for mesenchymal markers as well as for osteogenic and adipogenic differentiation. Results: The isolated cell population had fibroblast-like morphology and flow cytometry revealed that the mesenchymal surface markers were (means): CD90 (84.55), CD31 (39.97), CD166 (33.77), CD105 (31.19), CD45 (32/44), CD44 (462.11), CD34 (227.33), CD38 (86.94), CD13 (34.52) and CD73 (50.39). The PDL stem cells also differentiated into osteoblasts and adipocytes in osteogenic and adipogenic media, respectively. Conclusions: PDL stem cells expressed mesenchymal stem cell (MSC) markers and differentiated into osteoblasts and adipocytes in osteogenic and adipogenic media, respectively.

A survey of the safety conditions of student housings: A case study in a type one university in Shiraz, Iran

Objectives: This study aimed to investigate the extent of implementation of safety measures in 14 student housings in one of the largest universities in Fars province, Shiraz, Iran. Method: A cross-sectional study was conducted in 14 student housings of one of the largest universities, located in Shiraz, Iran. Audit checklists were completed and rated thought field inspection and interview. Safety Requirement Index (SRI) was then used to evaluate the safety of student housings. SRI was graded on five scales (0-19%: very poor (unsafe); 20-39%: poor (relatively unsafe); 40-59%: moderate; 60-79%: good (relatively safe): and 80-100%: excellent (safe). Results: The mean SRI score was 71.01±15.46%. The highest and lowest level of SRI was 94.11±6.60% for dimensions of public health (and 47.70±18.42% for elevator safety. Conclusion: None of the studied housings was completely safe in all dimensions. Most of the studied housings were categorized as safe in the dimensions of public health and ventilation and air-conditioning systems; relatively safe in the dimensions of electrical, building, fire and kitchen safety; and moderate in the elevator safety and emergency response. Establishment of safety management system is necessary to promote safety in the studied housings. The results of this study indicated the need to inform the authorities about the safety priorities in housings, to promote the safety conditions. The results could also be used to raise awareness regarding their role and responsibilities about the safety of housings

Oral Administration of Recombinant Saccharomyces boulardii Expressing Ovalbumin-CPE Fusion Protein Induces Antibody Response in Mice

Saccharomyces boulardii, a subspecies of Saccharomyces cerevisiae, is a well-known eukaryotic probiotic with many benefits for human health. In the present study, a recombinant strain of S. boulardii was prepared to use as a potential oral vaccine delivery vehicle. In this sense, a ura3 auxotroph strain of S. boulardii CNCM I-745 (known as S. cerevisiae HANSEN CBS 5926, Yomogi®) was generated using CRISPR/Cas9 methodology. Then a gene construct encoding a highly immunogenic protein, ovalbumin (OVA), was prepared and transformed into the ura3- S. boulardii. To facilitate the transport of the recombinant immunogen across the intestinal barrier, a claudin-targeting sequence from Clostridium perfringens enterotoxin (CPE) was added to the C-terminus of the expression cassette. The recombinant S. boulardii strain expressing the OVA-CPE fusion protein was then administered orally to a group of mice, and serum IgG and fecal IgA levels were evaluated by ELISA. Our results demonstrated that anti-OVA IgG in serum significantly increased in test group (P < 0.001) compared to control groups (receiving wild type S. boulardii or PBS), and the fecal IgA titer was significantly higher in test group (P < 0.05) than control groups. In parallel, a recombinant S. boulardii strain expressing the similar construct lacking C-terminal CPE was also administered orally. The result showed an increased level of serum IgG in group receiving yeasts expressing the CPE negative construct compared to control groups; however, the fecal IgA levels did not increase significantly. In conclusion, our findings indicated that the yeast S. boulardii, as a delivery vehicle with possible immunomodulatory effects, and c-CPE, as a targeting tag, synergistically assist to stimulate systemic and local immunity. This proposed recombinant S. boulardii system might be useful in the expression of other antigenic peptides, making it as a promising tool for oral delivery of vaccines or therapeutic proteins