Friday, July 17, 2015
Grand Hall and Gallery, Ground Floor & 1st Floor (Maritim Hotel)
Gingival mucosa (GM) diminishes with age resulting to no keratinized layer, decline in gingival fibroblast cells, and wider gingival crevice which we believe would allow target antigen to easily penetrate and induce an immune response, especially in an elderly host. However, the potential of GM as a vaccination route was never explored. In this study, we used elderly rats (77 week-old) and initially confirmed both gingival entry and optimal xanthan gel:antigen ratio using catechin. We found that higher catechin amounts enter the body through oral-supplementation (via GM) as compared to oral-administration. Moreover, we established that 100 mg mL-1 is the optimal amount for oral-supplementation. Subsequently, for vaccine testing, we used influenza H5N1 hemagglutinin (HA) as the target antigen and treated four sets of rats the same optimized antigen amount (via intradermal, oral, sublingual, and gingival route, respectively). Heart blood was obtained 14 days post-vaccination and blood sera were isolated for antibody measurement through a pre-optimized sandwich ELISA method. We found that gingival vaccination was able to induce an antibody response comparable to both oral and sublingual vaccination. This highlights the potential of GM as an alternative vaccination route which we propose can be applicable for elderly vaccination.