TLDR Applying a DNA vaccine to skin with active hair growth boosts immune response and protection against anthrax in mice.
The study demonstrated that applying a DNA vaccine topically onto skin areas where hair follicles were induced into the anagen-onset stage significantly enhanced the immune response in mice. This enhancement was due to increased antigen gene expression, plasmid DNA uptake, and moderate dermal inflammation. The anti-PA antibody levels were higher in the anagen-onset group compared to the telogen stage group and were comparable to intramuscular injection. Cholera toxin was necessary as an adjuvant, and a high DNA concentration was required for a detectable immune response. The study involved 5-7 female Balb/C mice per group and maintained skin integrity during the procedure.
124 citations
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April 2000 in “Nature biotechnology” 
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133 citations
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