HI-6 modulates immunization efficacy in a BALB/c mouse model

• HI-6 was known as an antidote for nerve agents.
• Recently, modulation of cholinergic anti-inflammatory pathway was reported.
• In the present work, ability of HI-6 to modulate immunity response was investigated.
• In the experiment, KLH and HI-6 were given to BALB/c laboratory mice.
• Improving of vaccination efficacy was proved.

HI-6 is used as an antidote to nerve agents. It can also act as an antagonist to acetylcholine receptors (AChRs) including the nicotinic receptor, α 7 nAChR which is involved in regulating the immune response through macrophages. This experiment investigated the efficacy of HI-6 to regulate the immune response. Laboratory BALB/c mice received HI-6 and/or keyhole limpet hemocyanin (KLH) as an antigen. Antibody production was investigated after either 21 or 65 days when either single or repeated dose of antigen was applied. We confirmed that HI-6 significantly improved vaccination efficacy when KLH was given in a dose of 1 mg/kg. The effect was dose dependent. A combination of HI-6 and KLH produced a vaccination of almost the same efficacy as that for Freund's complete adjuvant. The findings point at the suitability of HI-6 for improving vaccination efficacy at the level of immunity regulation by the nervous system.