Low back pain affects 80% of the population at some point in their lives, costing millions to the UK economy. Approximately 40% of all low back pain cases are caused by disease in the joints in the spine, known as the intervertebral discs. These discs enable the spine to move, bend and flex and act to absorb load during normal daily activities. Intervertebral discs are similar in structure to a jam doughnut, containing a soft gel (like the jam) surrounded by a stiffer elastic ring (like the dough in the doughnut). Disease of these spinal discs which is known as disc degeneration, is the result of abnormal cell behaviour and mechanical damage, which results in an increased production of natural chemicals which can damage the disc and stimulate local nerves, making the back very painful. Current treatments for low back pain do not target the cause of disc degeneration so they do not cure the patient, they simply treat the symptoms to make it less painful. Right now, the only successful approach surgeons use is the removal of disc material (the jam) which has squeezed out of the disc which presses nearby nerves. This surgery prevents further compression of the nerve root, making it less painful, however this is only a suitable treatment for a small proportion of sufferers where the middle of the disc has squeezed out and compresses the nerves. Most patients with low back pain without nerve compression currently have very limited treatment options. We have developed a new material (NPgel) which is a liquid outside of the body and can be injected directly into the disc via a needle without the need for major surgery. Following the injection into the disc the material becomes a gel, with similar mechanical properties to intervertebral disc tissue. In addition the material can be mixed with stem cells taken from the patient's own bone marrow, which will allow the growth of healthy new disc material in the diseased discs. The material can also be mixed with chemicals that prevent the native diseased cells of the disc from causing any further damage. Our material has the potential to stop the disease getting worse, whilst helping the growth of new disc tissue using the stem cells we inject into the disc. We have previously tested our gel material and shown it has similar mechanical properties to intervertebral disc tissue, and does not kill human bone marrow stem cells when they are mixed together. In addition we have previously shown that cells taken from healthy people and mixed into the NPgel change their behaviour and start producing the materials from which the spinal disc is made. Before we are allowed to perform clinical trials in humans, a series of laboratory and animal experiments are essential. We have completed initial animal safety studies showing our gel is not toxic. Here, we aim to complete mechanical tests and determine the behaviour of the gel and injected cells in a laboratory set-up which mimics the environment of the human disc. Once successful, we aim to begin studies on large animals, which is necessary before we can conduct clinical trials of our gel on people. If all this goes well, it could be used as a treatment to cure disc disease in less than 10 years.