Safety of Human Embryonic Stem Cell-derived Mesenchymal Stem Cells for Treating Interstitial Cystitis: A Phase I Study

Abstract

There are still no definite treatment modalities for interstitial cystitis (IC). Meanwhile, stem cell therapy is rising as potential alternative for various chronic diseases. This study aimed to investigate the safety of the clinical-grade mesenchymal stem cells (MSCs) derived from human embryonic stem cells (hESCs), code name MR-MC-01 (SNU42-MMSCs), in IC patients. Three female IC patients with (1) symptom duration >6 months, (2) visual pain analog scale (VAS) ≥4, and (3) one or two Hunner lesions <2 cm in-office cystoscopy within 1 month were included. Under general anesthesia, participants received cystoscopic submucosal injection of SNU42-MMSCs (2.0 × 107/5 mL) at the center or margin of Hunner lesions and other parts of the bladder wall except trigone with each injection volume of 1 mL. Follow-up was 1, 3, 6, 9, and 12 months postoperatively. Patients underwent scheduled follow-ups, and symptoms were evaluated with validated questionnaires at each visit. No SNU42-MMSCs-related adverse events including immune reaction and abnormalities on laboratory tests and image examinations were reported up to 12-month follow-up. VAS pain was temporarily improved in all subjects. No de novo Hunner lesions were observed and one lesion of the first subject was not identifiable on 12-month cystoscopy. This study reports the first clinical application of transurethral hESC-derived MSC injection in three patients with IC. hESC-based therapeutics was safe and proved to have potential therapeutic efficacy in IC patients. Stem cell therapy could be a potential therapeutic option for treating IC.

Keywords: Hunner lesion; clinical trial; embryonic stem cell; interstitial cystitis; mesenchymal stem cell.

The current manuscript describes the clinical trials of human embryonic stem cell (hESC)-derived multipotent mesenchymal stem cells (MMSCs) for patients with interstitial cystitis (IC). We provide the clinical importance and advance that cystoscopic submucosal injection of the hESC-derived MMSC was safe and exhibited potential therapeutic efficacy in human subjects, without no adverse events.

Figure 1.

Generation and characterization of clinical-grade SNU42-MMSCs. (a) Experimental scheme for the generation of clinical-grade MMSCs (SNU42-MMSC) using the Transwell-based differentiation of a hESC line, SNUhES42. (b) SNU42-MMSCs exhibited unique fibroblastic cell morphology. Scale bar = 500 µm. (c) SNU42-MMSCs were analyzed for specific surface antigen marker expression of MSCs (CD90, CD105, CD73, CD44, and CD29), pericytes (CD146 and NG2), hematopoietic stem cells (CD45 and CD34), pluripotent stem cells (OCT-3/4, TRA-1-60, and TRA-1-81), and MHC class I (HLA-ABC) and class II (HLA-DR). (d) Karyotypic analysis of SNU42-MMSCs. The isolated cells showed stable proliferation without chromosomal changes. (e) Differentiation potential of SNU42-MMSCs was shown by adipogenesis (left, Oil Red staining, scale bar = 50 µm), osteogenesis (middle, Alizarin Red S staining, scale bar = 200 µm), and chondrogenesis (right, Alcian blue staining, scale bar = 200 µm). (f) In vitro tube formation assay. Scale bar = 200 µm. (g) Dye transfer (circle in the plot) was detected in a co-culture of DiI-labeled SNU42-MMSCs (MMSC-DiI, red) and calcein-labeled human umbilical vein endothelial cells (HUVEC-Calcein, green). The results for the characterization of the research-grade (H9-MMSC) cells are presented in Supplementary Fig. 2.

Figure 2.

Therapeutic efficacy of SNU42-MMSCs in a preclinical study. (a) Representative awake cystometry results, (b) quantitative bladder voiding parameters, and histological examinations, and (c) at 1 week after the injection of the indicated MMSCs (1 × 10⁵ cells) or a single instillation of 50% DMSO. The clinical-grade SNU42-MMSC and research-grade H9-MMSC cells were established using the same differentiation procedure (porous membrane-mediated isolation of MSCs from different hESC lines). Data are presented as the mean ± SEM from two independent sets with five animals in each group. Statistical analyses were performed using one-way ANOVA with Bonferroni post hoc tests. *P < .05, **P < .01, ***P < .001 compared to the LPS-IC group; ^#P < .05, ^##P < .001, ^###P < .001 compared to the DMSO group, ^$$$P < .001. IAP, intra-abdominal pressure; IVP, intravesical pressure; Sham, sham-operated. Representative histological results are presented in Supplementary Fig. 5.

Figure 3.

Serial cystoscopic images of Hunner lesions in each patient. (a) Patient 1, (b) Patient 2, and (c) Patient 3. Hunner lesions in each patient at pre-, 1-month, 3-month, 6-month, and 12-month post-stem cell injection.