Haematophagous arthropod saliva and host defense system: a tale of tear and blood

Abstract

The saliva from blood-feeding arthropod vectors is enriched with molecules that display diverse functions that mediate a successful blood meal. They function not only as weapons against host's haemostatic, inflammatory and immune responses but also as important tools to pathogen establishment. Parasites, virus and bacteria taking advantage of vectors' armament have adapted to facilitate their entry in the host. Today, many salivary molecules have been identifi ed and characterized as new targets to the development of future vaccines. Here we focus on current information on vector's saliva and the molecules responsible to modify host's hemostasis and immune response, also regarding their role in disease transmission.

Human anti‐saliva immune response following experimental exposure to the visceral leishmaniasis vector, Lutzomyia longipalpis

“…Prior studies investigating host humoral responses against ectoparasite saliva has revealed an important role for IgG, with major contribution of isotype IgG1, IgM, and IgE [4,[37][38][39][40]. Our group has also investigated humoral response against sand fly saliva in a murine model [25], and in children living on an endemic area of visceral leishmaniasis [18].…”

“…Their saliva contains a number of molecules that modulate the host's hemostatic, inflam-matory, and immune responses (IR), probably representing an evasion mechanism to circumvent the host's homeostatic system [4]. Such effects seem to be important to create a favorable microenvironment on host's skin to establishment of parasites transmitted by the blood-sucking insects [5].…”

Anticoagulant activity in salivary gland homogenates of Thyrsopelma guianense (Diptera: Simuliidae), the primary vector of onchocerciasis in the Brazilian Amazon

“…Several salivary glands of hematophagous invertebrates have been intensively studied because they possess a variety of substances that are involved in counteracting the homeostatic systems and inflammatory reactions of the vertebrate host (Ribeiro 1987, 1995, Andrade et al 2005. In black flies, the study of salivary secretion function has been limited to the species S. vittatum (Jacobs et al 1990, Cross et al 1993, Cupp et al 1993, Abebe et al 1994, 1995, Andersen et al 2009.…”

Triatoma infestans Calreticulin: Gene Cloning and Expression of a Main Domain That Interacts with the Host Complement System

“…They counteract the hemostatic, inflammatory, and immune processes of the host, 6 such as vasoconstriction, blood coagulation, and platelet aggregation, [7][8][9][10][11] preventing the blood loss that follows tissue injury. However, the success of the hematophagic process also depends on innate and adaptive immune responses and, specially, on the complement system.…”