A 24-48 h fed Amblyomma americanum tick saliva immuno-proteome

Abstract

BackgroundMultiple tick saliva proteins, the majority of which are unknown, confer tick resistance in repeatedly infested animals. The objective of this study was to identify the 24-48 h fed Amblyomma americanum tick saliva immuno-proteome. The 24-48 h tick-feeding phase is critical to tick parasitism as it precedes important events in tick biology, blood meal feeding and disease agent transmission. Fed male, 24 and 96 h fed female phage display cDNA expression libraries were biopanned using rabbit antibodies to 24 and 48 h fed A. americanum female tick saliva proteins. Biopanned immuno-cDNA libraries were subjected to next generation sequencing, de novo assembly, and bioinformatic analysis.ResultsMore than 800 transcripts that code for 24-48 h fed A. americanum immuno-proteins are described. Of the 895 immuno-proteins, 52% (464/895) were provisionally identified based on matches in GenBank. Of these, ~19% (86/464) show high level of identity to other tick hypothetical proteins, and the rest include putative proteases (serine, cysteine, leukotriene A-4 hydrolase, carboxypeptidases, and metalloproteases), protease inhibitors (serine and cysteine protease inhibitors, tick carboxypeptidase inhibitor), and transporters and/or ligand binding proteins (histamine binding/lipocalin, fatty acid binding, calreticulin, hemelipoprotein, IgG binding protein, ferritin, insulin-like growth factor binding proteins, and evasin). Others include enzymes (glutathione transferase, cytochrome oxidase, protein disulfide isomerase), ribosomal proteins, and those of miscellaneous functions (histamine release factor, selenoproteins, tetraspanin, defensin, heat shock proteins).ConclusionsData here demonstrate that A. americanum secretes a complex cocktail of immunogenic tick saliva proteins during the first 24-48 h of feeding. Of significance, previously validated immunogenic tick saliva proteins including AV422 protein, calreticulin, histamine release factor, histamine binding/lipocalins, selenoproteins, and paramyosin were identified in this screen, supporting the specificity of the approach in this study. While descriptive, this study opens opportunities for in-depth tick feeding physiology studies.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2164-15-518) contains supplementary material, which is available to authorized users.

Tick attachment cement – reviewing the mysteries of a biological skin plug system

“…Nevertheless it became clear that the sheer quantity of proteins and other products of the salivary glands (Alarcon‐Chaidez, 2014) make assignment to particular functions such as cement formation difficult. To address this problem, temporary expression patterns of the salivary glands were analysed (Radulovic et al ., 2014; Kim et al ., 2016; Bullard, Williams & Karim, 2016), showing which salivary products were produced at certain points during feeding. These subsets of proteins were then tested for their functions by specific inactivation in living ticks and verification in feeding trials (Kim, Curran & Mulenga, 2014).…”

A Proteomic Analysis ofSarcoptes scabiei(Acari: Sarcoptidae)

“…We also identified a number of proteins with homology to putative tick proteins that are suspected to be involved in host-parasite molecular interactions (Radulovic et al 2014). Among these were homologs of calmodulin, calreticulin, lipocalin, and glutathione-S-transferase (Supp.…”

Ixodes scapularistick saliva proteins sequentially secreted every 24h during blood feeding

“…In an interesting approach to identify secreted tick salivary proteins (TSPs) Radulovic et. al., [40] and Lewis et. al., [41] used antibodies to 24-48 h tick saliva proteins [42,43] to immunoscreen phage display cDNA expression libraries to identify 24-48 h Amblyomma americanum and 24 h I. scapularis immunogenic tick saliva proteins.…”

“…moubata tHBP, referred to as moubatin, demonstrated inhibition of collagen induced platelet aggregation [96]. In a recent study, lipocalins/HBPs/FABPs were identified among 24-48 h A. americanum immunogenic tick saliva proteins [40] suggesting that these proteins are part of the tick saliva proteins that confer anti-tick resistance in repeatedly infested animals. It is notable that in Radulovic et al, [40], alongside lipocalins/HBPs, a leukotriene B4-like protease was also found among 24-48 h A. americanum immunogenic tick saliva proteins.…”

“…In a recent study, lipocalins/HBPs/FABPs were identified among 24-48 h A. americanum immunogenic tick saliva proteins [40] suggesting that these proteins are part of the tick saliva proteins that confer anti-tick resistance in repeatedly infested animals. It is notable that in Radulovic et al, [40], alongside lipocalins/HBPs, a leukotriene B4-like protease was also found among 24-48 h A. americanum immunogenic tick saliva proteins. It is interesting to note that Sequentially Secreted Ixodes scapularis Saliva Proteins I. ricinus, tHBP referred to as LIR6 bound leukotriene B4 [97], a pro-inflammatory mediator and a potent neutrophil chemoattractant.…”