cells Review Cellular Therapy via Spermatogonial Stem Cells for Treating Impaired Spermatogenesis, Non-Obstructive Azoospermia Nesma E. Abdelaal 1, Bereket Molla Tanga 2,3, Mai Abdelgawad 4, Sahar Allam 5 , Mostafa Fathi 6, Islam M. Saadeldin 7 , Seonggyu Bang 2 and Jongki Cho 2,* 1 Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Universite Paris-Saclay/Île-de-France, 91198 Gif-sur-Yvette, France;
[email protected] 2 College of Veterinary Medicine, Chungnam National University, Daejeon 34134, Korea;
[email protected] (B.M.T.);
[email protected] (S.B.) 3 Faculty of Veterinary Medicine, Hawassa University, P.O. Box 05 Hawassa, Ethiopia 4 Biotechnology and Life Sciences Department, Faculty of Postgraduate Studies for Advanced Sciences (PSAS), Beni-Suef University, Beni-Suef 62521, Egypt;
[email protected] 5 Faculty of Medicine, Tanta University, Tanta 31527, Egypt;
[email protected] 6 Biotechnology Program, Faculty of Agriculture, Ain Shams University, Giza 11566, Egypt;
[email protected] 7 Department of Physiology, Faculty of Veterinary Medicine, Zagazig University, Zagazig 44519, Egypt;
[email protected] * Correspondence:
[email protected]; Tel.: +82-42-821-6788 Abstract: Male infertility is a major health problem affecting about 8–12% of couples worldwide. Spermatogenesis starts in the early fetus and completes after puberty, passing through different stages. Male infertility can result from primary or congenital, acquired, or idiopathic causes. The Citation: Abdelaal, N.E.; Tanga, absence of sperm in semen, or azoospermia, results from non-obstructive causes (pretesticular and B.M.; Abdelgawad, M.; Allam, S.; testicular), and post-testicular obstructive causes.