California's Stem Cell Agency

The overall goal of this project is to develop a stem cell-based therapy for the treatment of urinary incontinence in women; therapies are also applicable for men. Urinary incontinence is very common and is linked to aging and to complications of pregnancy due to injury of the urethral sphincter. Our strategy consists of deriving induced pluripotent stem cell (iPSC) lines with a non-integrative technology that would not alter the gene content of cells, differentiating lines to smooth muscle cells, assessing characteristics of undifferentiated and differentiated cells, testing safety and efficacy and proceeding to initial discussions with the FDA. During this funding period, we have derived three affected and control lines, characterized the lines for standard properties of stem cell lines, optimized differentiation further and established initial benchmark assays for analysis of undifferentiated cells, as well as, established methods for animal studies. We have also focused on establishing protocols that eliminate animal cells and proteins from culture and media in order to provide the safest possible cells for eventual cell replacement therapies. We are on track with our milestones and are confident that the project will yield important results for the women, and men, of the state of California. In 2008, 20,330 women underwent surgery for urinary incontinence in California; this extrapolates to 172,500 UI procedures/year nationally (76,500 outpatient and 96,000 inpatient) and more than 100,000 procedures in California over the last 5 years. This number is forecast to increase by 55% by 205023. Yet, although short-term results of surgery are good, long-term results are not. Alternatives such as minimally invasive methods of injecting bulking agents, including collagen or autologous fat, provide only temporary and partial relief. Thus, our project is important as it aims to improve treatments in order to assist the significant number of patients without options for relief in the state of California.

Urinary incontinence (UI) is common and serious, with two-thirds of the burden borne by women. Our proposed development candidate is intended to treat UI by restoring normal function to the internal urethral sphincter via regenerative therapy modalities. The initial focus is on the treatment of UI in women refractory to other surgical interventions. The urethra is comprised of an internal urethral sphincter composed primarily of smooth muscle cells that control the flow of urine at the outlet of the bladder and an external urethral sphincter composed of voluntary skeletal muscle cells. The urethral wall also contains smooth muscle fibers and is supported by connective tissue. The total number of smooth muscle cells in the urethra decrease with aging, thus contributing to the high prevalence of incontinence amongst older individual. The discovery of genetic reprogramming methods to convert an adult cell into a cell with stem cell properties (induced pluripotent stem cells or iPSCs) has sparked strong interest in using these patient derived stem cells for regenerative therapies. The overall goal of this project is to develop an iPSC-based therapy for the treatment of stress urinary incontinence (SUI) in women. Our strategy consists of deriving iPSC lines with a non-integrative technology, differentiating lines to smooth muscle cells (SMC), assessing real-time characteristics of undifferentiated and differentiated cells, testing safety and efficacy in an animal model, and proceeding to initial discussions with the FDA. In previous reporting periods, we derived three patient lines, characterized the lines, optimized differentiation further and established initial benchmark in vitro assays for analysis of undifferentiated cells, as well as, established methods for animal studies. We have also focused on replacement of our protocol for differentiation with a protocol that removes rodent feeder cells and is carried out in chemically-defined media. In the current reporting period, we concentrated on optimizing our differentiation protocol for our patient-specific iPSC lines, increasing production of smooth muscle precursor cells, confirming SMC precursor in vivo integration and long term survival in animals, demonstrating efficacy of our pluripotent stem cell derived therapy, and examining mechanisms of action of our target therapy. We have completed four animal efficacy studies showing reproducible efficacy of our therapy derived from a human embryonic stem cell line and different iPSC lines (from different participants). Smooth muscle cell precursors derived from these lines are all able to restore urethral function and show long term survival and safety in animals. We also filed provisional patent application on our technology.