Recently, a collaborative study conducted by InnoStar and Cyberiad-Life (Shanghai) AI Tech Co., Ltd. ("Cyberiad-Life") developed a mouse testicular organoid model using 3D bioprinting technology for early-stage reproductive toxicity screening. The research paper, titled "Light-based 3D Bioprinting of Testicular Organoid as an In Vitro Model for Reproductive Toxicity Assessment," has been published in the internationally renowned journal ACS Biomater. Sci. Eng.

  Infertility is the third most significant disease this century after cancer and cardiovascular diseases. Approximately 8–15% of reproductive-age couples globally are affected, with male factors accounting for over 50% of cases. Male infertility has multiple causes, potentially related to congenital, acquired, or idiopathic factors impairing spermatogenesis, partially due to reproductive toxicity from environmental toxins or drugs.

The rapid growth in novel chemical compounds has increased toxicity evaluation demand, resulting in market supply shortages. The 3R Principles proposed by ICH in S5 guidelines have become scientific consensus. Therefore, establishing high-throughput alternative models for drug reproductive toxicity assessment is urgent.

 

Research Content:
Design of 3D Bioprinting Conditions and Culture Parameters for Mouse Testicular Organoid Generation: Through exploration of the testicular extracellular matrix, type I collagen was identified as the main component. GelMA was selected for bioink preparation. Based on the stiffness range of testicular tissue, the concentrations of components in the bioink were determined. By testing different printing parameters, the conditions for optimal printing status were screened. Cells exhibited good growth in the model, demonstrating its biocompatibility.

 

Establishment and Characterization of Bioprinted Testicular Organoids Using Prepubertal Mouse Cells:
By comparing cell states in two different culture media during testicular organoid cultivation, it was found that a medium with fixed additive factors better supported cell growth. Furthermore, macroscopically observable compartmentalized structures, similar to seminiferous tubules, formed during the culture process.

 

The testicular organoids exhibited compartmentalized tubular structures and retained key gonadal cell lineages:
IF staining revealed that after 14 days of organoid culture, cells gradually self-organized into seminiferous tubule-like structures. α-SMA formed a tubular structure with a lumen, DDX4 was distributed along the concave surface of α-SMA, GATA4 was intermixed with DDX4, and 3β-HSD showed uneven distribution among the tubular structures—consistent with their distribution in native testicular tissue.
 

 

Temporal changes in cell-type-specific gene expression profiles during in vitro testicular organoid culture:
Gene expression analysis demonstrated that the optimized organoid culture system supported long-term survival and maintenance of multiple testicular cell types. The gene expression profile of these organoids was very similar to that of in vivo testes, demonstrating the mature and functionally normal state of the 3D-bioprinted testicular organoids.
 

 

3D-bioprinted testicular organoids enable reproductive toxicity assessment:
This model can effectively detect all known toxic side effects of triptolide on testicular cells, precisely identify target cells, thereby providing richer information support for mechanism research. The mouse testicular organoid model preliminarily demonstrates potential as a platform for male reproductive toxicity assessment and mechanism research.

 

Highlight:

• Screening of the most suitable bioink for testicular cell growth

The organoid model constructed in this study accurately simulates the matrix composition and stiffness of testicular tissue. Compared with traditional culture methods, this culture significantly enhances cell-cell and cell-matrix interactions and signaling, providing a more in vivo-like model for male reproduction research.

• Optimizing culture conditions and medium formulation for testicular organoids

This study identified optimal conditions for mouse testicular organoid culture by optimizing 3D bioprinting material concentrations, printing parameters, culture methods, and medium composition.

• First established bioprinted testicular organoid model for triptolide toxicity assessment

Using optimized conditions and medium composition, compartmentalized tubular-structured testicular organoids were cultivated. Preliminary validation was performed with triptolide. This study confirms the potential of 3D-bioprinted models for early-stage drug toxicity screening, providing strong support for non-clinical drug safety evaluation.   This collaborative research achievement by InnoStar and Cyberiad-Life has established for the first time a light-based 3D bioprinting technology to manufacture testicular organoids, providing a high-throughput new method and model for preclinical drug safety evaluation. The integration of organoid technology with 3D bioprinting not only advances research on reproductive organoids but also provides critical foundations for future personalized model development. We anticipate this breakthrough will translate into clinical practice, bringing new hope to infertility patients.