Cytokines/growth factors are large, related groups of highly potent proteins which affect cell fate. Cytokine potency is counter-balanced by relatively short half-lives. This ephemeral nature produces spatiotemporal effects by limiting duration of cytokine bioactivity and therefore the distance they can travel within tissues.
The invention of induced pluripotent stem cell (iPSC) technology in 2006 by Shinya Yamanaka was a big moment for stem cell therapeutics. Using a cocktail of transcription factors to turn the clock back on (almost) any cell to its pluripotent past enables essentially unlimited quantities of any cell type to be made. iPSCs are similar to embryonic stem cells (ESCs) that had been isolated several years earlier. However, ESCs are derived from an early-stage embryo, so come with a lot of ethical baggage. Too much for many countries which simply banned the technique. As well as simpler ethics, iPSCs can be made using a patient’s own cells, enabling autologous cell therapy.
Macrophages are extraordinary cells. Not just for their phagocytic capacity, which is also shared by a few other cells, but also for their ability to dynamically adapt their function to intervene in unfolding events.
Until recently, pharmaceuticals were dominated by a single class of drugs, small molecules. Over the space of 25 years, advances in molecular biology have lead to the development of many new drug classes. Here’s my overview of pharmaceuticals, either marketed or in development, based on molecular entity, and roughly in order of the drugs physical size.
PD is a progressive degenerative neurological disease that affects about 1% of the population over age 55. Although there are many variants of the disease, a common strand that links these variants is damage to a finite group of dopaminergic (DA) neurons in the midbrain. As these neurons are lost in PD, CNS function and in particular its control over normal muscular function declines. Tremor is a well-known symptom which characterizes PD, but sleep, digestion, cognition, and mobility are also affected with increasing severity as the disease progresses. Current therapies, such as dopamine replacement therapy, only address symptoms and there is an urgent need for a disease-modifying therapy.
Cultured cells often require the addition of specific growth factors to enable proliferation, differentiation or survival. However, some recombinant proteins are expensive to use. This is either because they are difficult to make (and therefore costly) or they are simply needed in large amounts.
Everyone working in regenerative medicine today is standing in the shoulders of giants. The tools scientists have developed enable progress in the field and the creation of new therapies. Here’s my list of the regenerative medicine’s top molecular tools.
Regenerative medicine harnesses natural processes to replace and repair damaged or missing tissue. The tools used to achieve this are largely derived from nature and I’ve covered some of them in another post. Beyond regenerative medicine, some of the most important medical discoveries and other technologies have been made by observing or adapting nature. With the entire world as a lab and millions of years to perform their experiments, nature has developed solutions to problems that have benefits for humans. Here’s my list of the top 10 natural inventions, that have been harnessed or inspired medical and other applications.
Hearing loss will affect many of us in our lives. In the US between 25-48 million are currently affected by sensorineural hearing loss. This is typically a result of the loss of hairs in the inner ear which initiates a cascade of secondary events including loss of specialized neurons called spiral ganglion neurons (SGNs) which link these hairs to the brain. Cochlear implants can help restore hearing, but without functional SGNs to integrate the implant with the brain, their performance is limited.
Growth factors are small glycoproteins both made and used by all animal cells to communicate with other cells and regulate themselves. Growth factors provide constant feedback to nearby and distant cells, modulating cell behaviour. In research labs, recombinant growth factors are widely used for cell culture. Growth factors such as EPO, BMP-2 and IL-2 are used clinically and novel therapeutics for diseases such as Parkinson’s, osteoarthritis and cancer are in development.
