Balanced Th1/Th2 immune response induced by MSP1a functional motif coupled to multiwalled carbon nanotubes as anti-anaplasmosis vaccine in murine model

Anaplasmosis is one of the most prevalent tick-borne diseases of cattle caused by Anaplasma marginale. MSP1a surface protein has been shown to be involved in eliciting immunity to infected cattle. Carbon nanotubes (CNTs) has been increasingly highlighted due to their needle like structure, which contain multiple attachment sites for biomolecules and may interact with or cross biological membranes, increasing antigen availability to immune system. Here, we have successfully designed a nanocomplex of a synthetic peptide noncovalently attached to multiwalled CNT (MWCNT). Peptide comprising the core motif of the MSP1a was efficiently adsorb onto the nanoparticle surface. The MWCNT-Am1 nanocomplex exhibited high stability and good dispersibility and in vivo immunization showed high levels of IgG1 and IgG2a, followed by increased expression of pro-inflammatory and anti-inflammatory cytokines. This is a proof-of-concept of a nanovaccine that was able to generate a strong immune response compared to the common antigen-adjuvant vaccine without the nanoparticles. We successfully developed a nanovaccine against bovine anaplasmosis based on the noncovalent attachment of a synthetic peptide (Am1) containing a critical motif sequence of the MSP1a surface protein of Anaplasma marginale to oxidized MWCNTs (multiwalled carbon nanotubes). The reduced length and high stability of the nanocomplex allowed a potent and highly stable balanced Th1/Th2 immune response showing an equivalent level of antibody and better cell-mediated immune responses in mice, compared to the conventional immunization with antigen-adjuvant without nanoparticles. [Display omitted]