<scp> <i>Amblyomma cajennense</i> </scp> Sensu Stricto (Fabricius, 1787) and <scp> <i>Amblyomma sculptum</i> </scp> (Berlese, 1888) Tick Saliva Elicit Immune‐Modulatory Activity in Isolated Murine Macrophages With an Insight Into Proteomic Analysis

Tick saliva is known to cause immunosuppression and help pathogen transmission. Amblyomma sculptum is a public health concern as a vector of Rickettsia rickettsii. Another close-related species is Amblyomma cajennense sensu stricto (s.s.). The impact of saliva from these species on murine macrophages remains unclear. This study evaluated saliva from A. cajennense s.s. and A. sculptum in murine peritoneal macrophages, assessing cell viability, adhesion, morphology, reactive oxygen species (ROS) production, phagocytosis and cytokine secretion. Additionally, a proteomic analysis was conducted and the proteins that were secreted in salivas were estimated. Neither A. sculptum nor A. cajennense s.s. saliva did it affect viability, adhesion or morphology, but increased ROS production and phagocytic activity. A. sculptum saliva decreased IL-1β and increased TNF-α, whereas A. cajennense s.s. saliva increased IL-6 and IL-10. Proteomic analysis revealed 221 and 303 secreted proteins in A. cajennense s.s. and A. sculptum, respectively and the more abundant were vitellogenins, microplusins, serpins, cystatins, actin, beta actin and calponins. These findings suggest that saliva from each species modulates macrophage activity in distinct ways, eliciting pro- and anti-inflammatory responses. This is the first comparative evaluation of salivas from two species of the A. cajennense sensu lato complex, providing new insights into their interaction with innate immune cells.