Does photobiomodulation change the synthesis and secretion of angiogenic proteins by different pulp cell lineages?

This study aimed to compare the synthesis and secretion of VEGF-A, VEGF-C, VEGF-D, VEGFR1, VEGFR2, and FGF-2 between pulp fibroblasts from human primary teeth (HPF) and stem cell from human deciduous teeth (SHED) before and after photobiomodulation. HPF were obtained from explant technique and characterized by immunohistochemistry, while SHED were obtained from digestion technique and characterized by flow cytometry. HPF (control group) and SHED were plated, let to adhere, and put on serum starvation to synchronize the cell cycles prior to photobiomodulation. Then, both cell lineages were irradiated with 660-nm laser according to the following groups: 2.5 and 3.7 J/cm2. MTT and crystal violet assays respectively verified viability and proliferation. ELISA Multiplex Assay assessed the following proteins: VEGF-A, VEGF-C, VEGF-D, VEGFR1, VEGFR2, FGF-2, at 6, 12, and 24 h after photobiomodulation, in supernatant and lysate. Two-way ANOVA/Tukey test evaluated cell viability and proliferation, while angiogenic production and secretion values were analyzed by one-way ANOVA (P < .05). Statistically similar HPF and SHED viability and proliferation patterns occurred before and after photobiomodulation (P > .05). HPF exhibited statistically greater values of all angiogenic proteins than did SHED, at all study periods, except for FGF-2 (supernatant; 12 h); VEGFR1 (lysate; non-irradiated; 12 h); and VEGFR1 (lysate; non-irradiated; 24 h). Photobiomodulation changed the synthesis and secretion of angiogenic proteins by HPF. HPF produced and secreted greater values of all tested angiogenic proteins than did SHED before and after irradiation with both energy densities of 2.5 and 3.7 J/cm2.

Effects of PBM in different energy densities and irradiance on maintaining cell viability and proliferation of pulp fibroblasts from human primary teeth.

This study aimed to compare the effects of photobiomodulation (PBM) in different energy densities and irradiances on maintaining cell viability, and proliferation of pulp fibroblasts from human primary teeth (HPF) were cultured in DMEM and used between the fourth and eighth passages. Then, HPF were irradiated with the following different energy densities: 1.25 J/cm2 (a), 2.50 J/cm2 (b), 3.75 J/cm2 (c), 5.00 J/cm2 (d), and 6.25 J/cm2 (e); but varying either the time of irradiation (groups 1a-1e) or the output power (groups 2a-2e). Positive (groups 1f and 2f) and negative controls (groups 1g and 2g), respectively, comprised non-irradiated cells grown in regular nutritional conditions (10% fetal bovine serum [FBS]) and under nutritional deficit (1% FBS). Cell viability and proliferation were respectively assessed through MTT and crystal violet (CV) assays at 24, 48, and 72 h after irradiation. Statistical analysis was performed by two-way ANOVA, followed by Tukey test (P < 0.05). The negative controls showed significantly lower viability in relation to most of the corresponding subgroups, both for MTT and CV assays. For both assays, the intragroup comparison showed that the periods of 24 h exhibited lower viability than the periods of 48 and 72 h for most of the subgroups, except the negative controls with lower viability. The different irradiation protocols (equal energy densities applied with different irradiances) showed no statistically significant differences on cell viability and proliferation at the evaluated periods. The proposed PBM in different energy densities and irradiance did not affect the viability and proliferation of pulp fibroblasts from human primary teeth.

Storage protocol of dental pulp cells from human exfoliated deciduous teeth / Protocolo de armazenamento de células pulpares de dentes decíduos humanos

Objetivo: O objetivo deste estudo foi isolar células do tecido pulpar de dentes decíduos humanos, avaliar a capacidade de proliferação, caracterizá-las e normatizar as técnicas de cultivo e expansão celular destas para a criação de um banco de células. Material e métodos: Dentes decíduos sem cárie e com indicação ortodôntica de para extração foram utilizados como doadores de tecido para a pesquisa. As células foram extraídas de tecidos pulpares, isoladas e cultivadas em condições ideais até alcançarem confluência. Resultados: Após consecutivas passagens, as células cultivadas foram caracterizadas por meio de técnicas de imunofluorescência e congeladas entre a 2ª e a 6ª passagem, criando-se um biorrepositório de células da polpa de dentes decíduos humanos. Conclusão: A criação de bancos de células pulpares de dentes decíduos humanos permite uma aplicação mais ágil nas pesquisas laboratoriais, reduzindo o tempo e o custo da obtenção de novas amostras. Evita necessidade de triagem e obtenção de novos doadores de dentes e tecidos, e permite maior rapidez nas repetições de protocolos de pesquisas. (AU)

Objective: This study aimed to isolate the cells from the dental pulp tissue of human primary teeth, study the capacity of proliferation, characterize the cells and standardize the technique of culture and expansion to create a cell banking. Material and Methods: Primary teeth with no caries and orthodontic reasons were extracted for pulp tissue obtainment. The cells were extracted from the pulp cells, isolated and cultured under ideal conditions until full expansion. Results: After consecutive passages, the cultured cells were characterized using immunofluorescence technique and frozen between the 2nd and 6th passage, thus creating a biorepository of dental pulp cells from human primary teeth. Conclusion: The creation of a cell banking from dental pulp cells from human primary teeth enables the easy application of cells in laboratorial studies, reducing the cost and time for obtaining the samples, avoid the involvement of new subjects and allow a fast reproducibility of the researches. (AU)