The Role of Sleep in Supporting Immune System Function

Studies conducted experimentally and epidemiologically have demonstrated that sleep deprivation leads to an impaired immune response, suggesting it could be the key link between lack of restful sleep and NDDs risk and outcomes.

Now, researchers have identified another incentive to prioritize quality sleep: It enhances T cells’ capacity to combat infections such as influenza.

Increased Production of T Cells

Research suggests that sleep is an integral component of replenishing immune cells and increasing T cell responses in our bodies. Studies in which lymphocyte counts were measured show a distinct sleep-wake rhythm with peak times occurring during nocturnal sleep – this phenomenon was especially evident for T cells.

T cells activated during sleep exhibit higher levels of integrin activation, enabling them to attach and kill infected cells more effectively. Conversely, when healthy volunteers go without sleep for extended periods, T cell activation and killing of infected cells becomes significantly diminished.

Sleep also regulates cytokine production, an essential signal in immune signaling. Sleep deprivation causes decreased production of such essential cytokines as IL-1b and TNF-a that promote immune activation and pathogen defense; conversely, sleeping less results in decreased cortisol secretion which suppresses immunity resulting in decreased ability of our immune systems to fight viruses and cancer.

Reduced Inflammation

Studies have demonstrated the link between sleep and inflammation reduction, making you less susceptible to colds and getting enough rest, and lower risk.

T cells (white blood cells that fight infection) that have been sleep deprived show decreased ability to attach and destroy infected cells caused by viruses or pathogens, and produce anti-inflammatory cytokines like interleukin-6 and interleukin-12; production of nitric oxide, prostaglandins and growth hormone-releasing hormone also decreases.

Poor sleep can increase the risk of chronic diseases like heart disease, diabetes and neurodegenerative disorders; including autoimmune conditions like rheumatoid arthritis. Chronic poor sleep is a primary factor behind such conditions as it disrupts immune cell production patterns causing them to be more reactive and susceptible to inflammation.

Increased Immune Responses

Researchers found in a 2015 study that those deprived of sleep who were exposed to the common cold were more likely to become ill than those who received adequate amounts. Their researchers discovered that getting sufficient rest can help protect against illness by increasing immune T-cell production for fighting infection.

T cells are white blood cells that detect infected cells and work to destroy them through various techniques. Researchers found that sleep can improve T cell’s ability to recognise infected cells and bind with them – prompting additional immune responses that help destroy the infected cell and protect us against sickness.

Sleep was found to increase levels of cytokines that support antigen-presenting cell interactions, such as interleukin-12. Furthermore, it reduced rare CD14dimCD16+ monocytes with limited proinflammatory functions while simultaneously increasing immune-regulatory NK cells specialized in fighting cancer cells.

Reduced Risk of Infection

Scientists have discovered that sleep can help enhance the functioning of T cells, which play an essential role in fighting infections and preventing colds or flus. When T cells are active they have greater capabilities of attaching themselves to and eliminating infected cells from your system – while poor sleeping can inhibit T cell activation making you more prone to infections and colds.

Immune parameters such as numbers of undifferentiated naive T cells, pro-inflammatory cytokines and production of anti-inflammatory cytokines tend to peak during nocturnal sleep; conversely circulating numbers of immune cells with immediate effector functions – like cytotoxic natural killer cells and anti-inflammatory monocytes – tend to peak during wakefulness.

Studies conducted on humans which use short-term sleep deprivation to conduct vaccinations show that it significantly weakens their immune systems. This occurs due to reduced white blood cells present in lymph nodes following sleep disruption; this restricts your body’s ability to defend itself against infection. Furthermore, sleep disruption also decreases activity levels of specific subpopulations of white blood cells that battle cancer cells.