Abstract：Organoid is a tissue substitute that is structurally and functionally similar to the origin organ. At present, many organoid culture systems have been established, however testicular organoid culture is still in the exploratory stage. In this study, testicular tissues of Saanen dairy goats (Capra hircus) were taken, and testicular cells were isolated and cultured by mixed enzyme digestion. Testicular cells were cultured in three dimensions using a mixed medium containing low melting point agarose. The formed organoids were evaluated using light microscope and immunofluorescence detection techniques, and the culture effects of different sources of testicular cells, different numbers of testicular cells and different concentrations of low melting point agarose on testicular organoids were compared. Finally, the model function of the testicular organoid was verified by lipopolysaccharide (LPS) infection. The result showed that cells ranging from 2×105 to 3×105, in 1% low-melting-point agarose were more favorable for the formation of goat testicular organs in goats. The organoids formed possess seminiferous tubule-like structures, with spermatogonial stem cells and Sertoli cells evenly distributed within. Testicular organoid infected with LPS were smaller than normal organoids, exhibited cellular debris, and were accompanied by a significant increase in inflammatory factors, indicating that these organoids could respond to external stimuli and simulate the immune response of organs to a certain extent, making them a suitable model for the in vitro study of testicular diseases. This study not only promotes the development of testicular organoid culture technology, but also provides an important scientific basis and experimental platform for a variety of fields, including reproductive biology, disease modeling, drug screening, regenerative medicine, and personalized medicine.
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