In vitro cell culture of amniotic fluid keratinocytes on amniotic membrane: the ideal tissue for repairing skin ulcers.

OBJECTIVE: The amniotic fluid contains a large population of stem keratinocytes demonstrating minimal immunological rejection. Recent evidence suggests that stem cells from the amniotic fluid can be employed in the field of tissue engineering. In this work we identified precursors of the epithelial cells and expanded them in vitro. MATERIALS AND METHODS: After collecting samples of amniotic fluid and separating the cells via centrifugation, we seeded a portion of these cells in selection media to analyze the proliferation of epithelial cells. The stem cells precursors of keratinocytes were identified through specific markers. The expression of these markers was evaluated by immunofluorescence and reverse transcription polymerase chain reaction (PCR). RESULTS: The stem cells demonstrated 90% confluence, after undergoing proliferation in the selection medium for 15 days. Most of these cells tested positive for the keratinocyte-specific markers, but negative for stem cell specific markers. Of note, the identity of the keratinocytes was well established even after several subcultures. CONCLUSIONS: These results suggested that it is feasible to isolate and expand differentiated cell populations in the amniotic fluid from precursor cells. Furthermore, amniotic membranes can be utilized as scaffolds to grow keratinocytes, which can be potentially exploited in areas of skin ulcer transplantation and tissue engineering interventions.

Proposal of a food supplement for the management of post-COVID syndrome.

A vast majority of COVID-19 patients experience fatigue, extreme tiredness and symptoms that persist beyond the active phase of the disease. This condition is called post-COVID syndrome. The mechanisms by which the virus causes prolonged illness are still unclear. The aim of this review is to gather information regarding post-COVID syndrome so as to highlight its etiological basis and the nutritional regimes and supplements that can mitigate, alleviate or relieve the associated chronic fatigue, gastrointestinal disorders and continuing inflammatory reactions. Naturally-occurring food supplements, such as acetyl L-carnitine, hydroxytyrosol and vitamins B, C and D hold significant promise in the management of post-COVID syndrome. In this pilot observational study, we evaluated the effect of a food supplement containing hydroxytyrosol, acetyl L-carnitine and vitamins B, C and D in improving perceived fatigue in patients who recovered from COVID-19 but had post-COVID syndrome characterized by chronic fatigue. The results suggest that the food supplement could proceed to clinical trials of its efficacy in aiding the recovery of patients with long COVID.