Zisiadi Aimilia, Billooye Katy, Anckaert Ellen
Follicle Biology Laboratory, Research Group Genetics, Reproduction and Development (GRAD), Vrije Universiteit Brussel (VUB), Brussels, Belgium.
Department of Clinical Biology, Universitair Ziekenhuis Brussel (UZ Brussel), Brussels, Belgium.
Mol Hum Reprod. 2025 Jul 3;31(3). doi: 10.1093/molehr/gaaf029.
In vitro follicle culture (IFC) is an emerging fertility preservation alternative for women and children with cancer. Because two-dimensional (2D) IFC results in oocytes of suboptimal quality in mice and cannot support follicle growth in humans, the search for an optimal three-dimensional (3D) method that preserves the follicular structure is ongoing, and both matrix-free and hydrogel encapsulation systems are being explored. Our aim was to compare several 3D mouse IFC systems, including matrix-free and hydrogel encapsulation approaches. Secondary follicles were cultured for 12 days in a matrix-free non-attachment (NA) system, a Poly-Ethylene-Glycol (PEG) hydrogel, an extracellular-matrix-derived soft hydrogel (ES), and a 2D attachment (AT) control. We assessed follicle growth, survival, hormone secretion, theca cell localization, oocyte meiotic competence and diameter, gene expression in oocytes and cumulus cells, as well as oocyte fertilization potential. Metaphase II oocyte rates were significantly higher in the NA (75 ± 12.4%, n = 79) and AT systems (77 ± 12.6%, n = 109) compared to the ES (33.4 ± 9.5%, n = 40, P < 0.01), while low antral follicle rates from the PEG system led to its exclusion from the comparison. Similarly, following IVF, 2-cell rates were significantly higher in the NA (47.7 ± 17.6%, n = 147, P < 0.01) and AT (40.2 ± 9.7%, n = 132, P < 0.05) systems compared to the ES (23.5 ± 9.3%, n = 63). Furthermore, cumulus cells from the NA condition displayed a more in vivo-like gene expression profile than other conditions. No differences were detected in follicle survival, oocyte diameter, blastocyst rate, or quality between conditions. Lastly, we observed major differences in theca cell localization and hormone secretion levels that require further investigation. Our findings demonstrate the efficiency of the NA system over complex encapsulation methodologies, as it enhanced oocyte meiotic and developmental competence compared to the ES. However, as the study is limited by the lack of human data and the use of Fetal Bovine Serum (FBS) in the culture medium, further research is required to translate our findings to humans.
体外卵泡培养（IFC）是一种针对患有癌症的妇女和儿童的新兴生育力保存方法。由于二维（2D）IFC在小鼠中产生的卵母细胞质量欠佳，且无法支持人类卵泡生长，因此人们正在寻找一种能保留卵泡结构的最佳三维（3D）方法，同时也在探索无基质和水凝胶封装系统。我们的目的是比较几种三维小鼠IFC系统，包括无基质和水凝胶封装方法。次级卵泡在无基质非附着（NA）系统、聚乙二醇（PEG）水凝胶、细胞外基质衍生的软凝胶（ES）以及二维附着（AT）对照中培养12天。我们评估了卵泡生长、存活、激素分泌、卵泡膜细胞定位、卵母细胞减数分裂能力和直径、卵母细胞和卵丘细胞中的基因表达以及卵母细胞的受精潜力。与ES组（33.4±9.5%，n = 40，P < 0.01）相比，NA组（75±12.4%，n = 79）和AT系统（77±12.6%，n = 109）中的中期II卵母细胞率显著更高，而PEG系统中低窦卵泡率导致其被排除在比较之外。同样，体外受精后，与ES组（23.5±9.3%，n = 63）相比，NA组（47.7±17.6%，n = 147，P < 0.01）和AT组（40.2±9.7%，n = 132，P < 0.05）中的2细胞率显著更高。此外，与其他条件相比，NA条件下的卵丘细胞表现出更类似体内的基因表达谱。各条件之间在卵泡存活、卵母细胞直径、囊胚率或质量方面未检测到差异。最后，我们观察到卵泡膜细胞定位和激素分泌水平存在重大差异，需要进一步研究。我们的研究结果证明了NA系统相对于复杂封装方法的有效性，因为与ES相比，它增强了卵母细胞的减数分裂和发育能力。然而，由于该研究受到缺乏人类数据以及培养基中使用胎牛血清（FBS）的限制，需要进一步研究将我们的研究结果转化应用于人类。
