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Mesenchymal stem cells (MSCs) are promising for cell-based therapies targeting a wide range of diseases. However, challenges in translating MSC-based therapies to clinical applications necessitate standardized protocols following Good Manufacturing Practices (GMP) guidelines. This study aimed at developing GMP-complained protocols for FPMSCs isolation and manipulation, necessary for translational research, by (1) optimize culture of MSCs derived from an infrapatellar fat pad (FPMSC) condition through animal-free media comparison and (2) establish feasibility of MSC isolation, manufacturing and storage under GMP-compliance (GMP-FPMSC). FPMSCs from three different patients were isolated following established protocols and the efficacy of two animal component-free media formulations in the culturing media were evaluated. The impact of different media formulations on cell proliferation, purity, and potency of MSCs was evaluated through doubling time, colony forming unit assay, and percentage of MSCs, respectively. Furthermore, the isolation and expansion of GMP-FPMSCs from four additional donors were optimized and characterized at each stage according to GMP requirements. Viability and sterility were checked using Trypan Blue and Bact/Alert, respectively, while purity and identity were confirmed using Endotoxin, Mycoplasma assays, and Flow Cytometry. The study also included stability assessments post-thaw and viability assessment to determine the shelf-life of the final GMP-FPMSC product. Statistical analyses were conducted using one-way ANOVA with Tukey’s Multiple Comparisons. The study demonstrated that FPMSCs exhibited enhanced proliferation rates when cultured in MSC-Brew GMP Medium compared to standard MSC media. Cells cultured in this media showed lower doubling times across passages, indicating increased proliferation. Additionally, higher colony formation in FPMSCs cultured in MSC-Brew GMP Medium were observed, supporting enhanced potency. Data from our GMP validation, including cells from 4 different donors, showed post-thaw GMP-FPMSC maintained stem cell marker expression and all the specifications required for product release, including > 95% viability (> 70% is required) and sterility, even after extended storage (up to 180 days), demonstrating the reproducibility and potential of GMP-FPMSCs for clinical use as well as the robustness of the isolation and storage protocols. The study underscores the feasibility of FPMSCs for clinical uses under GMP conditions and emphasizes the importance of optimized culture protocols to improve cell proliferation and potency in MSC-based therapies. The online version contains supplementary material available at 10.1186/s12860-025-00539-7.

Hematologic adverse events are common dose-limiting toxicities in drug development. Classical animal models for preclinical safety assessment of immunotherapies are often limited due to insufficient cross-reactivity with non-human homologous proteins, immune system differences, and ethical considerations. Therefore, we evaluate a human bone marrow (BM) microphysiological system (MPS) for its ability to predict expected hematopoietic liabilities of immunotherapeutics. The BM-MPS consists of a closed microfluidic circuit containing a ceramic scaffold covered with human mesenchymal stromal cells and populated with human BM-derived CD34+ cells in chemically defined growth factor-enriched media. The model supports on-chip differentiation of erythroid, myeloid and NK cells from CD34+ cells over 31 days. The hematopoietic lineage balance and output is responsive to pro-inflammatory factors and cytokines. Treatment with a transferrin receptor-targeting IgG1 antibody results in inhibition of on-chip erythropoiesis. The immunocompetence of the chip is established by the addition of peripheral blood T cells in a fully autologous setup. Treatment with T cell bispecific antibodies induces T cell activation and target cell killing consistent with expected on-target off-tumor toxicities. In conclusion, this study provides a proof-of-concept that this BM-MPS is applicable for in vitro hematopoietic safety profiling of immunotherapeutics. Subject terms: Biologics, Haematopoiesis, Lab-on-a-chip, Drug safety

Induced pluripotent stem cell (iPSC)-derived mesenchymal stem cells (iMSCs) have greater potential for generating chondrocytes without hypertrophic and fibrotic phenotypes compared to bone marrow-derived mesenchymal stem/stromal cells (BMSCs). However, there is a lack of research demonstrating the use of autologous iMSCs for repairing articular chondral lesions in large animal models. In this study, we aimed to evaluate the effectiveness of autologous miniature pig (minipig) iMSC-chondrocyte (iMSC-Ch)-laden implants in comparison to autologous BMSC-chondrocyte (BMSC-Ch)-laden implants for cartilage repair in porcine femoral condyles. iMSCs and BMSCs were seeded into fibrin glue/nanofiber constructs and cultured with chondrogenic induction media for 7 days before implantation. To assess the regenerative capacity of the cells, 19 skeletally mature Yucatan minipigs were randomly divided into microfracture control, acellular scaffold, iMSC, and BMSC subgroups. A cylindrical defect measuring 7 mm in diameter and 0.6 mm in depth was created on the articular cartilage surface without violating the subchondral bone. The defects were then left untreated or treated with acellular or cellular implants. Both cellular implant-treated groups exhibited enhanced joint repair compared to the microfracture and acellular control groups. Immunofluorescence analysis yielded significant findings, showing that cartilage treated with iMSC-Ch implants exhibited higher expression of COL2A1 and minimal to no expression of COL1A1 and COL10A1, in contrast to the BMSC-Ch-treated group. This indicates that the iMSC-Ch implants generated more hyaline cartilage-like tissue compared to the BMSC-Ch implants. Our findings contribute to filling the knowledge gap regarding the use of autologous iPSC derivatives for cartilage repair in a translational animal model. Moreover, these results highlight their potential as a safe and effective therapeutic strategy. The online version contains supplementary material available at 10.1186/s13287-025-04215-7.