Abstract 487: Safety and functional profiling of clinical grade mesenchymal stem cells derived from bone marrow, adipose tissue and Wharton's jelly for cancer therapy

Abstract

Abstract Background: Mesenchymal stem cells (MSCs) have the potential as a drug delivery tool in cancer immunotherapy. We previously demonstrated that MSCs can be used to deliver BCG immunotherapy to the hypoxic core of tumors (#AACR-Abstract-3903). However, lack of clinical grade MSCs hamper the use of MSCs in clinical practice. The production of clinical grade human derived MSCs in accordance with current Good Manufacture Practice (cGMP) is an unmet need in the cancer immunotherapy. However, the selection criterion for characterizing the safety of MSC-based products is not well cited yet. In an effort to generate a potent therapeutic cell based product, we design a series of in-vitro safety assays for the production of high quality tissue specific human MSCs (hMSCs) as a final products before releasing from cGMP. Method: Here, we have isolated MSCs from Bone marrow (BM), Adipose tissue (AD) and Wharton Jelly (WJ) and expanded in serum free media. The in-vitro proliferation and phenotypic profiling of stem cell markers performed to check purity of the ex-vivo cultured hMSCs. To determine the clinical safety, we have done stemness marker analysis and cellular senescence capacity. To determine the functional aspects, tri-lineage differentiation and immunopotency of hMSCs were performed. Additionally, to assure the in vitro anti-tumorigenic properties of characterized hMSCs subjected to 2D colony forming unit (CFU) assay, 3D clonogenic assay as 3D organoid culture system and karyotyping. Results: Here, we proposed bioprocess design that allowed successful isolation of MSCs from BM, AD and WJ separately. Growth profiles of all isolated MSCs (n = 3) under serum free condition media with respect to serum containing media shows an exponential growth phase. The decline phase started after Day 7. Results also shows significant variation in population doubling time (PDT) of all isolated hMSCs at Passage 3 (n = 3) and Passage 5((n = 3) in comparison between serum free condition media & serum containing media. We found all hMSCs cultured in serum free media shows positive for CD105-APC (>80%), CD73-PE (>80%), CD90- PerCP (>80%), CD29- FITC (>80%) and HLAI (>80%), and negative HLAII- FITC(<2.20 %) and CD34/45- FITC (<2.20 %) expressions at Passage 3 & passage 5, indicating a stem cell phenotype (n = 3). Isolated hMSCs showed osteocyte, adipocytes and chondrocytes differentiation and high capacity to inhibit the proliferation of activated lymphocytes. Additionally, hMSCs positively expressed Nanog and Sox-2 stemness gene and cellular senescence from passage 7. In 2D CFU assay these cells showed colony forming capacity and in 3D organoid culture system in soft agar based matrix, we found that these cells are non-tumorigenic and didn't showed any karyotypic alteration. Conclusion: The collective result provides compelling evidence of the clinical safety of cGMP-compliant BM-MSCs, AD-MSCs and WJ-MSCs potentially suitable for future therapeutic application. Citation Format: Sorra Sandhya, Sonali Rawat, Suchi Gupta, Harshita Sharma, Bikul Das, Sujata Mohanty. Safety and functional profiling of clinical grade mesenchymal stem cells derived from bone marrow, adipose tissue and Wharton's jelly for cancer therapy [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 487.