Moderate alcohol consumption acts as vaccine adjuvant in monkeys

With the holidays nearing, alcohol consumption is going through its annual December spike. Data published this week suggests that anyone who receives a vaccine after a heavy drinking session will have a weak immune response, but moderate consumption could actually boost the effectiveness of a vaccine.

The data was published in the journal Vaccine by U.S. scientists who made 4% ethanol available to 12 male rhesus macaque monkeys. Each monkey was vaccinated at the start of the study and again after 7 months in which they had access to alcohol. The monkeys that drank the most experienced lower CD4 and CD8 T cell proliferation and immunoglobulin G IgG responses than the control group. Yet monkeys that only drank moderate amounts of alcohol had a stronger immune response than the controls.

Multiple studies in humans and animals have shown that heavy drinking dampens immune responses, but the effects seen in monkeys who only consumed moderate amounts of alcohol are less well documented. Earlier research has linked low levels of alcohol to decreased risk of cardiovascular disease in humans and stronger reactions to tumor cells in rats, though. The mechanisms underpinning these results are unclear, but researchers think the stronger immune response is linked to increased plasma cytokine levels.

Further research is needed to establish whether the effect of alcohol on the immune system has any implications for adjuvant development. Such immune response-boosting ingredients are in demand as vaccine developers pursue ever more challenging targets. Last week, a team at Massachusetts General Hospital published a paper on the effect of pretreating the site of an intradermal vaccination with laser light. The laser boosted the immune response to levels achieved by currently approved adjuvants.

- read the Vaccine abstract
- here's the laser news