Enhanced Mucosal IgA Response and Solid Protection Against Foot-and-Mouth Disease Virus Challenge Induced by a Novel Dendrimeric Peptide

Centro de Investigación en Sanidad Animal, INIA, Valdeolmos, 28130 Madrid, Spain; Departament de Ciències Experimentals i de la Salut, Universitat Pompeu-Fabra, 08003 Barcelona, Spain; Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Cantoblanco, 28049 Madrid Spain

^* To whom correspondence should be addressed. Email: fsobrino{at}cbm.uam.es.

	Abstract

The successful use of a dendrimeric peptide to protect pigs against challenge with foot-and-mouth disease virus (FMDV), which causes the most devastating animal disease worldwide, is described. Animals were immunized intramuscularly with a peptide containing one copy of a FMDV T-cell epitope and branching out into four copies of a B-cell epitope. The four immunized pigs did not develop significant clinical signs upon FMDV challenge, neither systemic nor mucosal FMDV replication, nor was its transmission to contact control pigs observed. The dendrimeric construction specifically induced high titers of FMDV neutralizing antibodies and activated FMDV-specific T cells. Interestingly, a potent anti-FMDV IgA response (local and systemic) was observed, despite the parenteral administration of the peptide. On the other hand, peptide-immunized animals showed no antibodies specific of FMDV infection, which qualifies the peptide as a potential marker vaccine. Overall, the dendrimeric peptide used elicited an immune response comparable to that found in control FMDV-infected pigs that correlated with a solid protection to FMDV challenge. Dendrimeric designs of this type may hold substantial promise for peptide subunit vaccine development.