Chronic low back pain exerts a significant socio-economic burden on society and is a major contributor to the growing opioid crisis. Last year, NIH ?launched the HEAL (Helping to End Addiction Long-term) initiative, an aggressive, trans-agency effort to speed scientific solutions to stem the national opioid public health crisis?. This enormous burden is largely because studies have failed to target the underlying mechanisms associated with pain generation. Intervertebral disc (IVD) degeneration is strongly associated with the pathophysiology of low back pain and identifying non-addictive minimally invasive treatments for discogenic back pain (DBP) is a research priority. Pathological IVD changes include extracellular matrix (ECM) breakdown, inflammation and aberrant nerve/vascular ingrowth which have been shown to significantly correlate with pain. Therefore the optimal therapy for DBP would target both structural restoration and reduce the symptoms of pain. Yet current strategies involving the use of stem cells or gene therapy are faced with a number of challenges which include failure of stem cells to adapt to the harsh IVD microenvironment, the use of viral vectors and unwarranted DNA deletions within the host genome. Furthermore clinicians do not have access to clinically relevant tools or technologies that could directly help treat the underlying disease in patients with DBP. There is a critical need for a biological non-addictive strategy that addresses these limitations. Our goal is to use novel cellular reprogramming technologies to alter the innate cell phenotype of native diseased IVD cells to a healthy extracellular producing and anti-catabolic/inflammatory phenotype in human in vitro cell culture and in vivo models of DBP. Non-viral delivery for transporting genetic cargo into the cell such as engineered extracellular vesicles (EVs) or tissue nano-transfection (TNT) offer safe and minimally invasive methods for reprogramming somatic cells and recent work by the investigators has demonstrated successful reprogramming of adult fibroblasts into endothelial cells in vivo mouse models. We propose using these innovative non-viral delivery systems to deliver genetic cargo to IVDs in vitro and in vivo. The first specific aim (R61 Phase 1 Aim 1) focuses on the effects of EV or TNT delivery of transcription factors on diseased human nucleus pulposus cells and tissue in vitro examining changes in ECM and catabolic, inflammatory and pain markers.
The second aim (R61 Phase 1 Aim 2) investigates the effects of EV or TNT delivery of transcription factors in mouse IVD puncture models of DBP assessing changes in disc structure/function, pain, cognition and cytotoxicity. These studies are both significant and highly innovative because they combine a unique multi-disciplinary team of medical and veterinary clinicians, spine biologists, neuroscientists, biomedical engineers, and a biostatistician to interrogate the use of these novel concepts and technologies to treat DBP. The broader impacts of this proposal and transition to the R33 portion involve assessing this strategy in clinically relevant chondrodystrophic dogs that develop DBP spontaneously followed by clinical trials in patient dogs with DBP.
The underlying causes of low back pain are an enigma despite the huge socio-economic burden of this debilitating disorder, with current surgical interventions proving ineffective and highly invasive. This proposal uses a multi-disciplinary approach to determine the effects of non-viral delivery of developmental transcription factors to reprogram diseased nucleus pulposus cells from painful intervertebral discs to a healthy biosynthetically active anti-catabolic/inflammatory/pain phenotype in vitro and in vivo using translational models that will ultimately lead to clinical trials in canine and human patients. Cellular reprogramming of intervertebral disc cells is a novel concept for the treatment of discogenic back pain and there is a critical need to develop non-addictive treatments that target both the underlying cause of disease as well as pain to improve human health and quality of life.
