Abstract
BACKGROUND: The cattle fever tick, Rhipicephalus microplus, is found in tropical and subtropical regions worldwide. Infestations of this tick lead to significant economic losses for cattle producers and dairy farmers, and the ticks can transmit a variety of pathogens that cause diseases such as babesiosis, anaplasmosis and theileriosis. The proteins Bm86, AQP1, AQP2 and VgR are expressed in various tick tissues, including the gut, salivary glands and ovaries. These proteins regulate essential physiological processes, including water balance (AQP1, AQP2), reproduction (VgR) and cell membrane integrity (Bm86). METHODS: Comprehensive bioinformatic and immunoinformatic analyses were conducted to evaluate Bm86, AQP1, AQP2 and VgR as potential vaccine targets against R. microplus. Specifically, we conducted studies on these proteins that included analysis of their physicochemical properties; topographical protein analyses; prediction of N-glycosylation sites, O-glycosylation sites, phosphorylation sites and B-cell and T-cell epitopes; and immune response simulation. The overall aim was to identify key epitopes and highlight their behavior within the host, representing a promising multicomponent vaccine formulation. RESULTS: The predictions for R. microplus Bm86, VgR, AQP1 and AQP2 proteins indicate strong antigenicity, low allergenicity and minimal toxicity, suggesting the potential for safe and effective immune response elicitation. The immune profile simulations for a cocktail of these proteins as vaccine candidates predicted consistently high levels of interferon-gamma and antibody isotypes, which could improve vaccine efficacy and control tick fitness and survivability in subsequent generations. CONCLUSIONS: The application of immunoinformatic tools for anti-tick vaccination was validated for the investigation of combining R. microplus Bm86, VgR, AQP1 and AQP2 proteins as a potential cocktail vaccine candidate.