How does alcohol consumption affect the immune system?

The immune system is broadly categorized into the innate and adaptive immune response systems, both of which are essential components of the body’s defense against pathogens.

Although the innate immune response is immediate, it is not specific to any given pathogen. Some of the most notable contributors to the innate immune response include natural killer (NK) cells, neutrophils, monocytes, macrophages, and dendritic cells (DCs).

These cells are able to recognize pathogen-associated molecular patterns (PAMPs) and pathogen recognition receptors (PRRs), which then allows these cells to engulf pathogenic microorganisms. Notably, innate immune cells secrete various cytokines and chemokines which ultimately lead to an inflammatory response.

The adaptive immune system can be subdivided into cell-mediated immunity and humoral immunity. While T lymphocytes are mainly involved in cell-mediated immunity, B lymphocytes play a major role in humoral immunity.

The first point of contact for alcohol after consumption is the gastrointestinal (GI) system before it is absorbed into the bloodstream. Here, alcohol can damage epithelial cells, T cells, and neutrophils in the gastrointestinal tract, all of which can impair gut barrier function and allow gut microorganisms to leak into the circulation.

In the gastrointestinal tract, exposure to alcohol can also alter the number and abundance of microorganisms present in the microbiome, all of which play an important role in normal gastrointestinal function. In addition to its detrimental effects on gastrointestinal functioning, alcohol’s impact on the gastrointestinal microbiome can also alter immune system maturation and function.

Several studies have demonstrated the dose-dependent effect of alcohol in preventing monocytes and macrophages from binding to lipopolysaccharide (LPS), a component of the bacterial cell wall.

Monocytes express Toll-like receptor (TLR) 4, the PRR which is often responsible for the recognition of LPS on the surface of Gram-negative bacteria. After binding to LPS, monocytes are activated and mature into macrophages which travel to the site of infection to secrete cytokines important for the inflammatory response.

Each of these events is mediated by the activation of nuclear factor kappa B (NFκB), which can be inhibited by alcohol consumption and thus prevent the production of pro-inflammatory cytokines. invivo studies have confirmed that excessive alcohol consumption with a blood alcohol concentration (BAC) of approximately 0.4% can reduce the production of various inflammatory cytokines, including interleukin-6 (IL- 6), IL-10 and IL-12.

In addition to laboratory studies confirming the impact of alcohol consumption on the innate immune system, several studies have examined how excessive alcohol consumption can alter plasma cytokine levels. To this end, a study analyzed the levels of IL-10, IL-6, IL-18 and tumor necrosis factor α (TNF-α) in 25 heavy drinkers seeking treatment. after consuming an alcoholic drink. Researchers reported significant reductions in TNF-α levels three and six hours after alcohol consumption.

Alcohol’s ability to alter both innate and adaptive immune defenses inevitably impacts how even a moderate alcohol drinker’s immune system may respond to infections. In fact, alcohol consumption has been shown to increase drinkers’ susceptibility to bacterial and viral infections, and advance the progression of several chronic viral infections, including human immunodeficiency virus (HIV) and hepatitis. vs.

How does alcohol affect your immune system? – BBCTo play