Study on the effect of dimethyl dioctadecyl ammonium bromide (DDA)‎ on the immune response of bivalent foot and mouth disease vaccine

Abstract EN

A vaccine strategy directed to increase both humeral and cellular immune responses, hereby examined the adjuvant effects of Dimethyl Dioctadecyl Ammonium Bromide (DDA), on a RNA vaccine.

The present study has been designed to follow up the capacity of Dimethyl Dioctadecyl Ammonium Bromide (DDA) which enhanced humeral and cell-mediated immune (CMI) responses of sheep to the bivalent FMD vaccine to levels, which were significantly higher than those induced by the vaccine alone.

Serologically using serum neutralization test (SNT) and enzyme linked immune sorbent assay (ELISA) it was found that there was a significant increase either in the protective level or duration of the immune response of vaccinated sheep to bivalent Alhydragel FMD vaccine containing DDA.

Furthermore, DDA enhanced the cell-mediated immune response of vaccinated sheep to higher levels than in those vaccinated with the vaccine without it, although there were no noticeable differences in the obtained ΔOD using either types (O or A) of FMD virus.

In addition, no post vaccination effects or local reactions were observed in inoculated sheep.

So it could be concluded that the use of DDA may be useful as an adjuvant for future vaccines.