Cytokine Storm Assays
Cytokine Release Syndrome
Cytokine storm, also called cytokine release syndrome (CRS), is a systemic inflammatory response marked by the dysregulated, large release of pro-inflammatory cytokines.
In the absence of infection or other immune-stimulating factors, cytokines coordinate the response of the immune system. This includes defending against pathogenic microbes and regulating the growth of abnormal cells. Most cytokines play complex roles within the immune system, and many have multiple and occasionally antithetical effects on different cell types. Generally, cytokines are grouped into broad categories of pro-inflammatory and anti-inflammatory based on their most frequent effector functions.
Cytokine regulation and immune response
Cytokine categories include interleukins, interferons, colony stimulating factors, tumour necrosis factors, and chemokines. More detailed information on key players such as IL-6 and TNFα is recommended for furthering understanding of the dynamic role these cytokines play in homeostatic conditions.
A cytokine storm is marked by the disruption of immune regulation causing an outpouring of pro-inflammatory cytokines, which in turn can spur the mass recruitment of immune cells. This has the potential to cause widespread inflammation and a severe decrease in the effective functionality of local organ systems.
Pathogensis due to Cytokine Storm (Cytokine Release Syndrome)
At this time, the pathogenesis of CRS is not fully understood. However, certain key effector cytokines of the pro-inflammatory variety have been discovered and are now used as therapeutic targets. The most commonly implicated cytokine in cytokine storms is interleukin 6 (IL-6), which acts through the JAK/STAT signalling pathway and can transduce a signal via soluble or transmembrane receptors. The IL-6 receptor’s dual signalling path may be a factor in the potent effect this cytokine can have in vivo.
In addition to IL-6, IL-10 and IFNγ are consistently implicated in reported cases of cytokine storms. These three cytokines are often found to be elevated in the serum of patients diagnosed with the syndrome. TNF, IL-1, IL-8 and MCP-1 are more prominent early in CRS onset, with IL-6 produced later in the progression of the syndrome in higher quantities. IL-6 production is increased by TNF and IL-1, thus linking the signal of early-response cytokines to late onset profiles. More information on cytokine storms is available in this article.