Human immune response to sand fly salivary gland antigens: a useful epidemiological marker?

Abstract

Abstract. Antibody (IgG) responses to salivary gland homogenate and to a recombinant salivary protein from the sand fly Lutzomyia longipalpis were investigated using sera from children living in an endemic area of visceral leishmaniasis in Brazil. We classified children into four groups according to their responses to Leishmania antigen: (Group I) positive serology and positive delayed type hypersensitivity (DTH), (Group II) positive serology and negative DTH, (Group III) negative serology and positive DTH, and (Group IV) negative serology and negative DTH. A highly significant correlation was found between anti-salivary gland IgG levels and DTH responses. An L. longipalpis salivary recombinant protein used as an antigen in an enzyme-linked immuno sorbent assay (ELISA) gave a significant but different result. A positive correlation was found between anti-Leishmania IgG and anti-recombinant protein IgG titers. The results indicate that sand fly salivary proteins may be of relevance to the study the epidemiology of leishmaniasis.

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

“…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]. In both reports, IgG levels significantly correlated with cellular IR, serving as epidemiological marker of sand fly exposure.…”

“…longipalpis, a vector of L. chagasi [18,19]. Intriguingly, this serological response correlated with a delayed-type hypersensitivity (DTH) reaction against L. chagasi [18,19].…”

“…longipalpis, a vector of L. chagasi [18,19]. Intriguingly, this serological response correlated with a delayed-type hypersensitivity (DTH) reaction against L. chagasi [18,19]. Furthermore, there was a simultaneous appearance of anti-saliva humoral response and anti-L. chagasi cell-mediated immunity [19], favoring the hypothesis that induction of IR against SGS may influence the generation of an IR against leishmaniasis.…”

“…ELISA was performed as described elsewhere [18]. Briefly, plates were coated with SGS equivalent to five pairs of salivary glands/mL in carbonate buffer overnight at 4 C, then washed with PBS/0.05% Tween and blocked with PBS/0.1% Tween plus 0.05% BSA.…”

Las glándulas salivales de dos flebotominos vectores de Leishmania: Lutzomyia migonei (França) y Lutzomyia ovallesi (Ortiz) (Diptera: Psychodidae)

“…The saliva acts as a lubricant, as a cleaner for mouthparts, and as as a food moisturizer; its enzymes aid in the digestion of blood as well as food rich in carbohydrates, and its anticoagulants prevent blood from clotting blood feeding (1)(2)(3)(4)(5)(6)(7). The saliva also assists the establishment of the parasite within the vertebrate host, and it affects the vector competence of these insects to transmit Leishmania (Ross) (Kinetoplastida: Trypanosomatidae) (6,(8)(9)(10)(11)(12)(13)(14).…”