The Biology of Fibrosis
Fibrosis is the harmful build-up of scar tissue that
leads to loss of tissue and organ function. A pathology common to a number
of serious and chronic diseases, fibrosis is a leading cause of morbidity and
mortality and can affect virtually all tissues and organ systems. Despite
the high prevalence of fibrosis and its enormous impact on human health, there
currently are no approved anti-fibrotic drug therapies in the
Groundbreaking New Insights
Breakthrough research by Promedior and its collaborators has identified the cellular source and control mechanisms for the initiation and progression of fibrotic and inflammatory diseases. In particular, a specific innate immune white blood cell population, called monocytes, has been shown to be the key regulator that promotes either resolution or progression of fibrotic disease. Monocytes have been identified as the source and master controller of key points in the pathways of fibrotic diseases including: the source of profibrotic and pro-inflammatory fibrocyte and M2 macrophage cell populations as well as pro-resolution cytokines, such as interleukin-10.
Monocytes Control the Fibrotic Process
Monocytes Are The Master Controller: Vital to the immune system’s response to chronic or acute injury, monocytes are the key source and master controller cells that initiate and drive the pathological progression of fibrosis. During normal healing they also trigger signaling cytokines and chemokines that direct the immune response to resolve fibrosis or inflammation.
Many individual and redundant stimuli, including cytokines, growth factors
and chemokines, activate monocytes and the downstream fibrocyte and profibrotic
(M2) macrophage cell populations. Although fibrosis has been an area of active
research for many years, the inherent biological complexity underlying fibrosis
has, in the past, created a significant challenge for drug development. With a
large number of individual and redundant stimuli attempting to “wall off” the
injury through production of fibrotic scar tissue, it has been difficult to
effectively reverse the process and stimulate resolution, until now.
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