We tend to think of inflammatory cytokines as inherently bad, driving chronic diseases and autoimmunity; however they play a vital role in the immune system, protecting us from infection and stimulating the healing of injuries. When immune cells such as macrophages are exposed to infectious organisms (pathogen-associated molecular patterns or PAMPs) or tissue injury (damage-associated molecular patterns or DAMPs), they secrete inflammatory cytokines such as tumour necrosis factor alpha (TNF-α), interleukin (IL) -1 and IL-6, along with chemokines, prostaglandins, leukotrienes and complement. Together, these stimulate and draw immune effector cells to the area to deal with the infection or damage.¹

TNF-α stimulates the acute phase of the immune response, and recruits lymphocytes, neutrophils and monocytes to the area of infection or damage.¹

IL-1α and IL-1β recruit neutrophils to the affected area, enhance the expansion and differentiation of helper T cells, and facilitate the entry of white blood cells into the affected tissue.¹

IL-6 promotes differentiation of B cells into plasma cells, activates cytotoxic T cells, recruits monocytes to the inflammation site, promotes the maintenance of Th17 cells, and inhibits T cell apoptosis. Additionally, anti-inflammatory properties are elicited via IL-6 under certain conditions, taming down the immune response and preventing uncontrolled inflammation.¹

Medicinal mushrooms stimulate the immune response by increasing the expression of these cytokines.² Ex-vivo studies conducted in partnership with Griffith University examined the effects of mushroom extracts on cytokine expression in human macrophages. The extracts increased the expression of TNF-α, IL-1α and IL-6, and reduced the expression of immune-suppressing IL-10 in a dose dependant manner. Additionally, a specific combination of Maitake, Reishi and Shiitake mushroom extracts demonstrated an apparent synergistic effects, increasing the expression of these cytokines far beyond that expected.³

References

Arango Duque G, Descoteaux A. Macrophage cytokines: involvement in immunity and infectious diseases. Front Immunol. 2014;5:491. https://doi.org/10.3389/fimmu.2014.00491

Chan GC, Chan WK, Sze DM. The effects of beta-glucan on human immune and cancer cells. J Hematol Oncol. 2009 Jun 10;2:25. https://doi.org/10.1186/1756-8722-2-25

Mallard B, Leach DN, Wohlmuth H, Tiralongo J. Synergistic immuno-modulatory activity in human macrophages of a medicinal mushroom formulation consisting of Reishi, Shiitake and Maitake. PLoS One. 2019;14(11):e0224740. https://doi.org/10.1371/journal.pone.0224740