In Vitro Spermatogenesis in Organ Culture Systems

In vitro spermatogenesis in organ culture systems encompasses methodologies that sustain and promote the full progression of male germ cell development outside the body, within explanted testicular tissue. Traditional approaches involve placing thin fragments of testis tissue at a gas–liquid interphase, supplying nutrients and hormonal cues akin to physiological conditions. These organ cultures support the sequence from spermatogonial stem cells through mitotic amplification, meiotic division and haploid spermatid formation, culminating in functional spermatozoa. Key challenges have included central necrosis due to limited oxygen and nutrient diffusion, undefined components in serum supplements, and incomplete maturation beyond the pachytene stage in non-mouse species. Recent innovations harness microfluidic platforms to mimic vascular perfusion, chemically defined media to replace animal serum, three-dimensional scaffolds to preserve multicellular architecture and co-culture with supporting Sertoli and Leydig cells to recreate paracrine signalling. Advances in cryopreservation of immature tissue and transcriptomic profiling have elucidated molecular bottlenecks and inflammatory responses during ex vivo culture. The global significance of this field spans fertility preservation for pre-pubertal patients, toxicity screening for environmental and pharmacological agents, and the foundational understanding of spermatogenic regulation. Ongoing work aims to refine oxygen tension, metabolic flux and growth factor supplementation to achieve reproducible, species-transcendent systems capable of generating genetically and functionally mature gametes.

Research from Nature Portfolio

A microfluidic device has been demonstrated to maintain mouse testis tissue for extended periods by separating the explant from flowing medium via a porous membrane, thereby replicating in vivo microvascular support. This innovation preserved spermatogenesis for six months, yielded functional sperm capable of fertilisation and sustained endocrine activity, offering a paradigm for long-term ex vivo organ culture. Building on methodological foundations, modifications of the air–liquid interphase method with tailored chemical supplements, antioxidants and reduced oxygen tension have enabled rat testis tissues to progress to round spermatids over 70 days. These optimised conditions reveal both shared and species-specific requirements for organ culture systems. More recently, further adjustment of culture media guided by metabolomic analysis allowed rat tissues to reach elongating spermatid stages and supported microinsemination that produced healthy, fertile offspring. This milestone extends functional in vitro spermatogenesis beyond rodents with established protocols, laying groundwork for translational applications across mammalian species.

In Vitro Spermatogenesis in Organ Culture Systems publication trend

The graph below shows the total number of articles in in vitro spermatogenesis in organ culture systems across all publications each year (not limited to Nature Index journals).

Technical terms

Organ culture: An ex vivo method in which intact tissue fragments are maintained at a gas–liquid interphase to preserve three-dimensional architecture and cell–cell interactions.

Spermatogonial stem cell (SSC): A self-renewing germ cell population that gives rise to all stages of spermatogenesis.

Round spermatid: A haploid germ cell formed after meiotic division, preceding elongation and condensation into mature spermatozoa.

Microfluidic device: A system of microscale channels that permits controlled perfusion of culture medium, mimicking in vivo vascular flow.

Testis-on-a-chip: A microphysiological platform replicating testicular microenvironment, including supporting somatic cells and extracellular matrix components.

References

1. Development of a novel testis-on-a-chip that demonstrates reciprocal crosstalk between Sertoli and Leydig cells in testicular tissue. Experimental & Molecular Medicine (2024).
2. Throughout in vitro first spermatogenic wave: Next-generation sequencing gene expression patterns of fresh and cryopreserved prepubertal mice testicular tissue explants. Frontiers in Endocrinology (2023).
3. In vitro spermatogenesis: In search of fully defined conditions. Frontiers in Cell and Developmental Biology (2023).
4. Generation of rat offspring using spermatids produced through in vitro spermatogenesis. Scientific Reports (2023).
5. Long-term ex vivo maintenance of testis tissues producing fertile sperm in a microfluidic device. Scientific Reports (2016).
6. Rat in vitro spermatogenesis promoted by chemical supplementations and oxygen-tension control. Scientific Reports (2021).