Original paper Tβ4 in the foetal ovary and its increase in the adult oocytes indicates a role of the peptide not only in germ cell development but also in its maintenance during adult life. In this study, Tβ4 was frequently detected not only inside of cells but also in the stroma surrounding gland structures both in foetuses and in adults. Considering the fact that the extracellular forms of beta-thymosins have been shown to selectively prevent neuronal cell death,27 we can speculate that the same role could be played by Tβ4 in the genitourinary tract during development. This role should be elucidated in further studies. Finally, our study clearly shows that further work is required to better understand the presence of Tβ4 and its impacts on development and on biological behaviour of adult cells in different human organs, which confirms Tβ4 as a versatile pep- tide with several, mostly unknown important functions in human health and disease. References 1. Mannherz HG, Hannappel E. 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