title: De novo morphogenesis of testis tissue: an improved bioassay to investigate the role of VEGF165 during testis formation.
abstract: De novo formation of testis tissue from single-cell suspensions allows manipulation of different testicular compartments before grafting to study testicular development and the spermatogonial stem cell niche. However, the low percentages of newly formed seminiferous tubules supporting complete spermatogenesis and lack of a defined protocol have limited the use of this bioassay. Low spermatogenic efficiency in de novo formed tissue could result from the scarcity of germ cells in the donor cell suspension, cell damage caused by handling or from hypoxia during tissue formation in the host environment. In this study, we compared different proportions of spermatogonia in the donor cell suspension and the use of Matrigel as a scaffold to support de novo tissue formation and spermatogenesis. Then, we used the system to investigate the role of vascular endothelial growth factor 165 (VEGF165) during testicular morphogenesis on blood vessel and seminiferous tubule formation, and on presence of germ cells in the de novo developed tubules. Our results show that donor cell pellets with 10×10(6) porcine neonatal testicular cells in Matrigel efficiently formed testis tissue de novo. Contrary to what was expected, the enrichment of the cell suspension with germ cells did not result in higher numbers of tubules supporting spermatogenesis. The addition of VEGF165 did not improve blood vessel or tubule formation, but it enhanced the number of tubules containing spermatogonia. These results indicate that spermatogenic efficiency was improved by the addition of Matrigel, and that VEGF165 may have a protective role supporting germ cell establishment in their niche.
authors.affiliation: Department of Comparative Biology and Experimental MedicineFaculty of Veterinary Medicine, University of Calgary, 3330 Hospital Drive NW, HMRB 404, Calgary, Alberta, Canada T2N 4N1.
authors.forename: Camila
authors.initials: C
authors.lastname: Dores
authors.affiliation: Department of Comparative Biology and Experimental MedicineFaculty of Veterinary Medicine, University of Calgary, 3330 Hospital Drive NW, HMRB 404, Calgary, Alberta, Canada T2N 4N1 idobrins@ucalgary.ca.
authors.forename: Ina
authors.initials: I
authors.lastname: Dobrinski
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002478:Cells, Cultured; D060833:Cellular Microenvironment / Q000187:drug effects; D003094:Collagen / Q000378:metabolism; D004338:Drug Combinations; D006085:Graft Survival / Q000187:drug effects; D007797:Laminin / Q000378:metabolism; D008297:Male; D016513:Mice, SCID; D009024:Morphogenesis / Q000187:drug effects; D009919:Orchiectomy; D011509:Proteoglycans / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects*; D013091:Spermatogenesis / Q000187:drug effects; D013093:Spermatogonia / Q000187:drug effects* / Q000378:metabolism / Q000637:transplantation*; D034421:Sus scrofa; D013737:Testis / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism / Q000637:transplantation*; D013997:Time Factors; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds; D042461:Vascular Endothelial Growth Factor A / Q000494:pharmacology*
chemical_list: D004338:Drug Combinations; D007797:Laminin; D011509:Proteoglycans; D011994:Recombinant Proteins; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; C059485:matrigel; D003094:Collagen