A putative role for eosinophils in tick rejection

Schleger, AV; Lincoln, Doug; Kemp, D. H.

doi:10.1007/bf01965562

Cited by 20 publications

(13 citation statements)

References 14 publications

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“…The difference between the results of Schleger et al and our results might be explained by the differences in the size of the area over which the eosinophils were counted at larval attachment sites, being smaller and located immediately under the larval mouthparts in study of Schleger et al versus larger and located around the tick mouthparts in our trial, the time of collection of skin samples (3 hour post‐infestation in study of Schleger et al and 24 hour post‐infestation in the present trial) and the genetic composition of the cattle ( B. taurus in study of Schleger et al and a composite breed, Santa Gertrudis: 5/8 B. taurus and 3/8 B. indicus, in the present trial). Taken together, these results provide some support for the view that in B. taurus cattle, eosinophil concentration at larval attachment sites is associated with larval rejection …”

Section: Discussionsupporting

confidence: 76%

“…In a previous trial, eosinophils infiltrated the larval attachment sites earliest after larvae successfully attached to the skin of the host and they were more numerous in B. taurus than in B. indicus cattle and in follow‐up infestations compared with primary infestations . Furthermore, in B. taurus cattle, the level of resistance to tick infestation correlated with eosinophil concentration and degranulation at larval attachment sites . In our trial, the number of eosinophils at larval attachment sites tended to be higher in resistant animals than in susceptible animals but it was not significantly higher.…”

Section: Discussionsupporting

confidence: 46%

“…However, the immune response plays an important role in protection . In cattle with natural infestations, the contribution to host resistance of circulating IgG and IgM specific to tick antigens (Ag) is debatable but there is evidence that the cellular immune response is essential for tick resistance . Resistance in B. taurus cattle was associated with a type I hypersensitivity reaction to larval allergens, and it was correlated with eosinophil concentration and degree of degranulation, mast cell disruption and number of intra‐epidermal vesicles at the larval attachment site …”

Section: Introductionmentioning

confidence: 99%

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Local immune response to larvae of Rhipicephalus microplus in Santa Gertrudis cattle

Constantinoiu

Lew-Tabor

Jackson

et al. 2018

Parasite Immunology

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This study investigated the local immune response at larval attachment sites in Santa Gertrudis cattle with low and high levels of tick resistance. Skin samples with tick larvae attached were collected from Santa Gertrudis cattle at the end of a period of 25 weekly infestations, when the animals manifested highly divergent tick-resistant phenotypes. There was a tendency for more CD3 , CD4 , CD8 , CD25 , γδ T cells and neutrophils to concentrate at larval tick attachment site in susceptible cattle than in resistant cattle but the differences were significant only for γδ T cells and CD4 cells. Most of the cattle developed intra-epidermal vesicles at the larval attachment site but the predominant cell within or around the vesicles was the neutrophil in susceptible animals and eosinophil in the resistant animals. The monoclonal antibodies (mAbs) specific for CD45 and CD45 RO antigens reacted with skin leucocytes from a higher number of susceptible cattle than resistant cattle. Our data suggest that some of the cellular responses mounted at larval attachment site are not involved in tick protection. The mAbs specific for CD45 and CD45 RO directly, or a test for CD45 genotype might be developed as markers of tick susceptibility or resistance.

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Section: Discussionsupporting

confidence: 76%

Section: Discussionsupporting

confidence: 46%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Local immune response to larvae of Rhipicephalus microplus in Santa Gertrudis cattle

Constantinoiu

Lew-Tabor

Jackson

et al. 2018

Parasite Immunology

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“…For example, recent evidence suggests that eosinophils suppress Th17 and Th1 responses via dendritic cell regulation and also activate basophil degranulation (Wen and Rothenberg, 2016 ). Eosinophils may influence the tick resistant phenotype due to their role in the translocation of mast cell histamine and lysosomal enzymes to the feeding site lesion, and by impairing tick attachment (Schleger et al, 1981 ). B. t. taurus show higher eosinophil counts during secondary infestations compared with B. t. indicus breeds in early studies (Tatchell and Moorhouse, 1968 ).…”

Section: Cellular Physiology Associated With Host Resistancementioning

confidence: 99%

Cattle Tick Rhipicephalus microplus-Host Interface: A Review of Resistant and Susceptible Host Responses

Tabor

Ali

Rehman

et al. 2017

Front. Cell. Infect. Microbiol.

102

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Ticks are able to transmit tick-borne infectious agents to vertebrate hosts which cause major constraints to public and livestock health. The costs associated with mortality, relapse, treatments, and decreased production yields are economically significant. Ticks adapted to a hematophagous existence after the vertebrate hemostatic system evolved into a multi-layered defense system against foreign invasion (pathogens and ectoparasites), blood loss, and immune responses. Subsequently, ticks evolved by developing an ability to suppress the vertebrate host immune system with a devastating impact particularly for exotic and crossbred cattle. Host genetics defines the immune responsiveness against ticks and tick-borne pathogens. To gain an insight into the naturally acquired resistant and susceptible cattle breed against ticks, studies have been conducted comparing the incidence of tick infestation on bovine hosts from divergent genetic backgrounds. It is well-documented that purebred and crossbred Bos taurus indicus cattle are more resistant to ticks and tick-borne pathogens compared to purebred European Bos taurus taurus cattle. Genetic studies identifying Quantitative Trait Loci markers using microsatellites and SNPs have been inconsistent with very low percentages relating phenotypic variation with tick infestation. Several skin gene expression and immunological studies have been undertaken using different breeds, different samples (peripheral blood, skin with tick feeding), infestation protocols and geographic environments. Susceptible breeds were commonly found to be associated with the increased expression of toll like receptors, MHC Class II, calcium binding proteins, and complement factors with an increased presence of neutrophils in the skin following tick feeding. Resistant breeds had higher levels of T cells present in the skin prior to tick infestation and thus seem to respond to ticks more efficiently. The skin of resistant breeds also contained higher numbers of eosinophils, mast cells and basophils with up-regulated proteases, cathepsins, keratins, collagens and extracellular matrix proteins in response to feeding ticks. Here we review immunological and molecular determinants that explore the cattle tick Rhipicephalus microplus-host resistance phenomenon as well as contemplating new insights and future directions to study tick resistance and susceptibility, in order to facilitate interventions for tick control.

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“…Since rRmS-3 and rRmS-17 have anti-chymotrypsin activity, these serpins could inhibit chymotrypsin-like proteases from cattle eosinophils. Interesting, the importance of eosinophils for tick feeding was highlighted in studies showing hosts upon repeated tick infestation present eosinophil accumulation in the attachment site, which has been linked to tick resistance (Brown et al, 1982; Carvalho et al, 2010; Schleger et al, 1981; Ushio et al, 1993). …”

Section: Discussionmentioning

confidence: 99%

The putative role of Rhipicephalus microplus salivary serpins in the tick-host relationship

Tirloni

Kim

Coutinho

et al. 2016

Insect Biochemistry and Molecular Biology

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Inflammation and haemostasis are part of the host's first line of defense to tick feeding. These systems are in part serine protease mediated and are tightly controlled by their endogenous inhibitors, in the serpin superfamily (serine protease inhibitors). From this perspective ticks are thought to use serpins to evade host defenses during feeding. The cattle tick Rhipicephalus microplus encodes at least 24 serpins, of which RmS-3, RmS-6, and RmS-17 were previously identified in saliva of this tick. In this study, we screened inhibitor functions of these three saliva serpins against a panel of 16 proteases across the mammalian defense pathway. Our data confirm that Pichia pastorisexpressed rRmS-3, rRmS-6, and rRmS-17 are likely inhibitors of pro-inflammatory and pro-coagulant proteases. We show that rRmS-3 inhibited chymotrypsin and cathepsin G with stoichiometry of inhibition (SI) indices of 1.8 and 2.0, and pancreatic elastase with SI higher than 10. Likewise, rRmS-6 inhibited trypsin with SI of 2.6, chymotrypsin, factor Xa, factor XIa, and plasmin with SI higher than 10, while rRmS-17 inhibited trypsin, cathepsin G, chymotrypsin, plasmin, and factor XIa with SI of 1.6, 2.6, 2.7, 3.4, and 9.0, respectively. Additionally, we observed the formation of irreversible complexes between rRmS-3 and chymotrypsin, rRmS-6/rRmS-17 and trypsin, and rRmS-3/rRmS-17 and cathepsin G, which is consistent with typical mechanism of inhibitory serpins. In blood clotting assays, rRmS-17 delayed plasma clotting by 60 s in recalcification time assay, while rRmS-3 and rRmS-6 did not have any effect. Consistent with inhibitor function profiling data, 2.0 µM rRmS-3 and rRmS-17 inhibited cathepsin G-activated platelet aggregation in a dose-responsive manner by up to 96% and 95% respectively. Of significant interest, polyclonal antibodies blocked inhibitory functions of the three serpins. Also notable, antibodies to Amblyomma americanum, Ixodes scapularis, and R. sanguineus tick saliva proteins cross-reacted with the three R. microplus saliva serpins, suggesting the potential of these proteins as candidates for universal anti-tick vaccines.

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A putative role for eosinophils in tick rejection

Abstract: In the reaction of Bos taurus cattle to infestation by the tick Boophilus microplus, mast cell histamine is translocated by the eosinophils to the attachment site. The concentration pattern of this cutaneous mediator for pain appears related to the grooming behaviour of the host.

Cited by 20 publications

References 14 publications

Local immune response to larvae of Rhipicephalus microplus in Santa Gertrudis cattle

Local immune response to larvae of Rhipicephalus microplus in Santa Gertrudis cattle

Cattle Tick Rhipicephalus microplus-Host Interface: A Review of Resistant and Susceptible Host Responses

The putative role of Rhipicephalus microplus salivary serpins in the tick-host relationship

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