Gametes are cells that have the unique ability to give rise to new individuals as well as transmit (epi)genetic information across generations. Generation of functionally competent gametes, oocytes... Show moreGametes are cells that have the unique ability to give rise to new individuals as well as transmit (epi)genetic information across generations. Generation of functionally competent gametes, oocytes and sperm cells, depends to some extent on several fundamental processes that occur during fetal development. Direct studies on human fetal germ cells remain hindered by ethical considerations and inaccessibility to human fetal material. Therefore, the majority of our current knowledge of germ cell development still comes from an invaluable body of research performed using different mammalian species. During the last decade, our understanding of human fetal germ cells has increased due to the successful use of human pluripotent stem cells to model aspects of human early gametogenesis and advancements on single-cell omics. Together, this has contributed to determine the cell types and associated molecular signatures in the developing human gonads. In this review, we will put in perspective the knowledge obtained from several mammalian models (mouse, monkey, pig). Moreover, we will discuss the main events during human fetal (female) early gametogenesis and how the dysregulation of this highly complex and lengthy process can link to infertility later in life. Show less
Gurp, L. van; Loomans, C.J.M.; Krieken, P.P. van; Dharmadhikari, G.; Jansen, E.; Ringnalda, F.C.A.S.; ... ; Koning, E.J.P. de 2016
The embryonic development of the human cochlea (the organ of hearing) has been investigated for over one hundred years. However, little is still known about the development on a cellular and... Show moreThe embryonic development of the human cochlea (the organ of hearing) has been investigated for over one hundred years. However, little is still known about the development on a cellular and protein level, which is important to better understand etiologies and pathologies of various types of sensorineural hearing loss. Knowledge of the normal gene expression patterns and cell fate specification in the human cochlea has therefore the potential to aid in the development of gene and cell-based therapeutic strategies. For this reason, we acquired a series of human fetal cochlea of different stages of gestation and investigated several aspects of the normal development of the human cochlea such as the hair cells, the spiral ganglion neurons and the stria vascularis. Also, we investigated the neural crest stem cells residing in the hair follicle bulge. We showed that a protein (TUBB3) often used in immunochemistry to detect a neuron is also expressed both in skin and hair follicle melanocytes in humans meaning that the proposed neural crest stem cell residing in the hair follicle bulge might need revision. Show less
