Oogonial stem cell (OSC)

Oogonial stem cells (OSCs), frequently termed egg precursor cells, are a rare population of mitotically active diploid germ cells found in the postnatal mammalian ovarian cortex that possess the capacity to differentiate into oocytes [1, 5]. Their discovery challenged the long-standing biological dogma that the female ovarian reserve is fixed at birth and cannot be replenished postnatally [2, 4]. These cells are molecularly characterized by the expression of germline-specific markers such as DDX4 (VASA) and DAZL, as well as pluripotency-associated factors like OCT4 and NANOG [5, 16]. In a therapeutic context, OSCs have been investigated for their potential to treat infertility and premature ovarian insufficiency, most notably as a source of healthy autologous mitochondria for transfer into poor-quality oocytes (the AUGMENT procedure) [5, 29]. Despite their potential, the existence and physiological significance of OSCs in adult humans remain subjects of significant scientific debate, with some research failing to confirm their ability to contribute to the functional oocyte pool in vivo [6, 7]. Ongoing studies focus on using these cells for in vitro gametogenesis (IVG) to address age-related infertility, though safety concerns regarding genetic and epigenetic stability remain paramount [11, 14].

Other names

Egg precursor cellFemale germline stem cellMitotically active germ cellOogonial progenitor cell

Oogonial stem cells are not traditional molecular targets for drugs; rather, they are utilized in regenerative medicine through autologous mitochondrial transfer to improve oocyte quality or through in vitro gametogenesis (IVG) to generate de novo oocytes for infertility treatment.