Fol. Biol. 2022, 68, 45-49
Time and Temperature Stability of TGF-β1, EGF and IGF-1 in 20% and 100% Human Serum
Autologous serum eye drops (ASEDs) are used as a treatment for severe dry eye disease. The concentration and stability of various growth factors in ASEDs is determinative for their efficiency. We therefore assessed the concentrations of transforming growth factor beta 1 (TGF-β1), epidermal growth factor (EGF) and insulin-like growth factor 1 (IGF-1) in ASEDs following storage at 4–8, −20, −80 and −156 °C. Twenty % and 100% sera from eight healthy volunteers were analysed by the sandwich enzyme immunoassay at different time intervals up to seven months. The mean levels of TGF-β1 and EGF in undiluted and 20% serum did not differ significantly from the baseline levels in fresh serum for any storage conditions after 7 days at 4–8 °C, as well as after 4- and 7-month preservation at sub-zero temperatures. In 20% serum, no IGF-1 concentration decrease was found following 7 days of preservation at 4–8 °C. However, a decrease to 78 % and 81 % (P < 0.01) of baseline values was found in 20% serum after 4-month storage at −20 °C and 7-month storage at −156 °C, respectively. A more pronounced decrease in IGF-1 was observed in undiluted serum. All assessed growth factors present in 20% frozen serum remained stable for up to 7 months. The highest stability was achieved at −80 °C. At −20 and −156 °C, some decrease in IGF-1 occurred. Our results indicate that 20% ASEDs can be stored frozen up to 7 months under proper conditions.
Funding
This study was supported by research project BBMRI_CZ LM 2018125 and by the European Regional Development Fund (project EF16_013/0001674). Institutional support (Charles University, Prague) was provided by programme Cooperatio: Medical Diagnostics and Basic Medical Sciences and by research project MH CZ DRO VFN 64165.
References
Copyright
This is an open-access article distributed under the terms of the Creative Commons Attribution License.
