Tick immunity using mRNA, DNA and protein-based Salp14 delivery strategies

Area of Science:

• Immunology
• Parasitology
• Vaccine Development

Background:

• Guinea pigs develop acquired resistance to Ixodes scapularis ticks, known as tick immunity.
• Tick immunity is influenced by salivary components, including the anticoagulant Salp14, which is associated with partial immunity.

Purpose of the Study:

• To investigate how different antigen delivery platforms (mRNA-LNPs, DNA, recombinant protein) influence the development of tick immunity using Salp14 as a model antigen.
• To evaluate the efficacy of mRNA-LNPs in eliciting early hallmarks of tick resistance.

Main Methods:

• Utilized Salp14 as a model antigen delivered via mRNA-lipid nanoparticles (LNPs), plasmid DNA, or recombinant protein.
• Assessed tick immunity by measuring erythema at the tick bite site and evaluating humoral and cellular responses post-tick challenge.

Main Results:

• mRNA-LNP vaccination elicited earlier and more pronounced erythema at the tick bite site compared to DNA or protein immunizations.
• Immune responses were directed towards a specific carboxy-terminal region of Salp14.
• mRNA-LNPs demonstrated potential in eliciting early indicators of acquired tick resistance.

Conclusions:

• The vaccine platform significantly influences the development of tick immunity in guinea pigs.
• mRNA-LNPs represent a promising platform for developing vaccines against tick-borne diseases by enhancing tick resistance mechanisms.