3D Bioprinted Endometrial Patch Enhances Regeneration and Fertility through Organotypic Endometrial Architecture

Intrauterine adhesions (IUA), a severe condition of endometrial injury, remains a major cause of female infertility due to the lack of effective long-term regenerative therapies. To address this unmet clinical need, we develop an engineered endometrial patch (EEP) fabricated by three-dimensional bioprinting of a porcine endometrium-derived decellularized extracellular matrix bioink loaded with endometrial epithelial organoids, stromal-immune populations, and endothelial cells. The spatially organized, tri-layered construct recapitulates the native architecture of the endometrium and supports epithelial polarity, vascularization, immune modulation, and hormone responsiveness. In a rat model of IUA, EEP transplantation markedly reduced fibrosis and rescued fertility with healthy offspring across generation by restoring endometrial receptivity and tissue integrity. Transcriptomic analysis revealed activation of stem cell proliferation, epithelial development and angiogenesis pathways, highlighting a mechanistic alignment with native tissue repair. Scalable fabrication of human cell-based patches which was administered into the cavity of the endometrium of IUA rabbit model further demonstrated translational adaptability. Together, our findings establish the EEP as a clinically applicable and customizable therapeutic strategy for endometrial regeneration for patients with infertility. Overall design: 8-week-old of female rats were anesthetized via intraperitoneal injection of 2,2,2-Tribromoethanol (250 mg/kg). A small incision was made along both sides of the lateral abdominal midline to expose the uterine horns. A 23G needle bent at a 45° angle was used to mechanically abrade the endometrial lining in all directions until the surface appeared bloody and pale. Two days after IUA induction, the EEP was carefully inserted into one uterine horn, while the contralateral horn served as an internal control or given transplantation control patch (CP; Endo-UdECM printed without cells). For RNA sequencing, uterine tissues from each experimental group were harvested and total RNA was extracted. Libraries were prepared using QuantSeq 3' mRNA-Seq Library Prep Kit (Lexogen, Inc., Austria) according to the manufacturer's instructions, and sequenced on a NextSeq500 (Illumina, Inc., USA) in single-end mode (75 bp). Sequencing reads were aligned to the reference genome or transcriptome using Bowtie2. Transcript assembly, quantification, and identification of DEGs were performed using Bedtools and EdgeR (Bioconductor).