Growth factors sustain primordial germ cell survival, proliferation and entering into meiosis in the absence of somatic cells.
It is known that mammalian primordial germ cells (PGCs), the precursors of oocytes and prospermatogonia, depend for survival and proliferation on specific growth factors and other undetermined compounds. Adhesion to neighboring somatic cells is also believed to be crucial for preventing PGC apoptosis occurring when they lose appropriate cell to cell contacts. This explains the current impossibility to maintain isolated mouse PGCs in culture for periods longer than a few hours in the absence of suitable cell feeder layers producing soluble factors and expressing surface molecules necessary for preventing PGTC apoptosis and stimulating their proliferation. In the present paper, we identified a cocktail of soluble growth factors, namely KL, LIF, BMP-4, SDF-1, bFGF and compounds (N-acetyl-L-cysteine, forskolin, retinoic acid) able to sustain the survival and self-renewal of mouse PGCs in the absence of somatic cell support. We show that under culture conditions allowing PGC adhesion to an acellular substrate, such growth factors and compounds were able to prevent the occurrence of significant levels of apoptosis in PGCs for two days, stimulate their proliferation and, when LIF was omitted from the cocktail, allow most of them to enter into and progress through meiotic prophase I. These results consent for the first time to establish culture conditions for purified mammalian PGCs in the absence of somatic cell support and should make easier the molecular dissection of the processes governing the development of such cells crucial for early gametogenesis.
Farini
Donatella
D
Department of Public Health and Cell Biology, Section of Histology and Embryology, University of Rome Tor Vergata, Via Montpellier 1, Rome 00173, Italy.
Scaldaferri
Maria Lucia
ML
Iona
Saveria
S
La Sala
Gina
G
De Felici
Massimo
M
D000111:Acetylcysteine / Q000494:pharmacology; D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D005576:Colforsin / Q000494:pharmacology; D005260:Female; D005854:Germ Cells / Q000166:cytology* / Q000187:drug effects*; D006133:Growth Substances / Q000494:pharmacology*; D066298:In Vitro Techniques; D015850:Interleukin-6 / Q000494:pharmacology; D053605:Leukemia Inhibitory Factor; D008297:Male; D008540:Meiosis / Q000187:drug effects; D051379:Mice; D009865:Oocytes / Q000166:cytology / Q000187:drug effects; D009866:Oogenesis / Q000187:drug effects; D013091:Spermatogenesis / Q000187:drug effects; D013093:Spermatogonia / Q000166:cytology / Q000187:drug effects; D013234:Stem Cells / Q000166:cytology* / Q000187:drug effects*; D014212:Tretinoin / Q000494:pharmacology
D006133:Growth Substances; D015850:Interleukin-6; D053605:Leukemia Inhibitory Factor; C507838:Lif protein, mouse; D005576:Colforsin; D014212:Tretinoin; D000111:Acetylcysteine