How excess alcohol depresses immune function

Alcoholism suppresses the immune system, resulting in a high risk of serious, and even life-threatening infections. A new study shows that this effect stems largely from alcohol’s toxicity to immune system cells called dendritic cells. These cells play a critical role in immune function, responding to danger signals by searching for unfamiliar antigens within the body that would be coming from invading microbes, and presenting such antigens to T cells, thus activating them to seek and destroy cells containing these antigens. The research is published in the July 2011 issue of the journal Clinical and Vaccine Immunology.

Earlier studies in mice had shown that excessive drinking of impaired T cell function, and subsequently that this impairment could be reversed by exposure to dendritic (so named for their shape) from non-alcoholic mice, and that poor function in CD4 and CD8 T cells could be improved through exposure to cytokines produced by non-alcoholic dendritic cells. (Cytokines are immune regulatory cells.) In this study, Jack R. Wands and colleagues of Brown University, Providence, RI, compared dendritic cells produced by alcoholic and non-alcoholic mice, which they first removed from the mice.  

The result: dendritic cells from the alcoholic mice had a poor ability to activate T cells, while the dendritic cells from mice on isocaloric diets containing no alcohol functioned normally. The researchers found further that the dendritic cells from alcohol-fed mice showed reduced antigen presentation compared to those from control mice, as well as less production of the regulatory cytokines. This research also confirmed earlier results showing that alcohol inhibits cytokine secretion by dendritic cells.

“This research helps us understand why alcoholics are predisposed to bacterial and viral infections, and why they do not respond well to vaccines,” says Wands. Understanding this, he says, will help in the development of ways to improve dendritic cell function in people with syndromes. 

More information: A. Eden, et al., 2011. Ethanol inhibits antigen presentation by dendritic cells. Clin. Vaccine Immunol. 18:1157-1166.)

Provided by American Society for Microbiology

not rated yet
add to favorites email to friend print save as pdf

Related Stories

Gene that suppresses cell's immune activation identified

Mar 24, 2011

(PhysOrg.com) -- A new study of prostate tumors has shown that a gene, FOXO3, suppresses activation of cells related to immunity and thus leads to a reduced immune response against a growing cancer. One of the main ...

Immune cells reveal fancy footwork

Dec 01, 2008

Our immune system plays an essential role in protecting us from diseases, but how does it do this exactly? Dutch biologist Suzanne van Helden discovered that before dendritic cells move to the lymph nodes they lose their ...

Skin sentry cells promote distinct immune responses

Jul 21, 2011

A new study reveals that just as different soldiers in the field have different jobs, subsets of a type of immune cell that polices the barriers of the body can promote unique and opposite immune responses against the same ...

New origin found for a critical immune response

Mar 01, 2009

An immune system response that is critical to the first stages of fighting off viruses and harmful bacteria comes from an entirely different direction than most scientists had thought, according to a finding by researchers ...

'Super' enzyme may lead way to better tumor vaccines

Dec 04, 2006

A "super" form of the enzyme Akt1 could provide the key to boosting the effect of tumor vaccines by extending the lives of dendritic cells, the immune-system master switches that promote the response of T-cells, which attack ...

Recommended for you

LED exposure is not harmful to human dermal fibroblasts

11 hours ago

There was a time when no one thought about light bulbs—one blew, you screwed another one in. Nowadays, it's more complicated, as energy efficiency concerns have given rise to a slew of options, including ...

User comments