Determination of Total Protein and Calcium in Gingival Mesenchymal Stem Cell-Conditioned Medium

Gingival mesenchymal stem cell-conditioned medium (GMSC-CM) is a conditioned medium obtained from cultured gingival mesenchymal stem cells. GMSCs are easily isolated from gingival tissue, whereas gingival tissue is easily obtained by minimally invasive techniques. On the other hand, CM contains proteins, cytokines, chemokines and growth factors that play an important role in osteogenic differentiation.This study aims to determine the total protein and calcium levels in GMSC-CM.GMSCs were grown in culture media with 10% of FBS. CM of GMSC was obtained from the media collection process with a 0.22 µm filter and concentrated with a centrifugal filter to obtain a concentrated GMSC-CM. The concentration of total protein was performed by bicinchoninic acid protein assay on GMSC-CM and concentrated GMSC-CM. Calcium level was performed by atomic absorption spectroscopy method. The results arethat GMSC-CM had a total protein concentration of 2502±0.06 µg/ml, and the concentratedGMSC-CM was 1.912±0.08 μg/ml.The calcium level of GMSC-CM was 0.009% and concentratedGMSC-CM was 0.009%. It can be concluded thatGMSC-CM had a high concentration of total protein and calcium. These parameters were used to develop bioprocesses to enhance the production of GMSC-CM, which will support the implementation of cell-free therapy for tissue regeneration.

Protective effects of low-molecular-weight components of adipose stem cell-derived conditioned medium on dry eye syndrome in mice

The present study demonstrated the protective effects of low-molecular-weight adipose-derived stem cell-conditioned medium (LADSC-CM) in a mouse model of dry eye syndrome. Mice subjected to desiccating stress and benzalkonium chloride had decreased tear secretion, impaired corneal epithelial tight junction with microvilli, and decreased conjunctival goblet cells. Topical application of adipose-derived stem cell-conditioned medium (ADSC-CM) stimulated lacrimal tear secretion, preserved tight junction and microvilli of the corneal epithelium, and increased the density of goblet cells and MUC16 expression in the conjunctiva. The low-molecular-weight fractions (< 10 kDa and < 3 kDa) of ADSC-CM (LADSC-CM) provided better protections than the > 10 kDa or > 3 kDa fractions of ADSC-CM. In the in vitro study, desiccation for 10 min or hyperosmolarity (490 osmols) for 24 h caused decreased viability of human corneal epithelial cells, which were reversed by LADSC-CM. The active ingredients in the LADSC-CM were lipophobic and stable after heating and lyophilization. Our study demonstrated that LADSC-CM had beneficial effects on experimental dry eye. It is worthy of further exploration for the active ingredient(s) and the mechanism.