Molecular Investigation and Phylogeny of Anaplasma spp. in Mediterranean Ruminants Reveal the Presence of Neutrophil-Tropic Strains Closely Related to A. platys

Abstract

Few data are available on the prevalence and molecular typing of species belonging to the genus Anaplasma in Mediterranean ruminants. In this study, PCR analysis and sequencing of both 16S rRNA and groEL genes were combined to investigate the presence, prevalence, and molecular traits of Anaplasma spp. in ruminants sampled on the Island of Sardinia, chosen as a subtropical representative area. The results demonstrate a high prevalence of Anaplasma spp. in ruminants, with animals infected by at least four of six Anaplasma species (Anaplasma marginale, A. bovis, A. ovis, and A. phagocytophilum). Moreover, ruminants host a number of neutrophil-tropic strains genetically closely related to the canine pathogen A. platys. The high Anaplasma spp. prevalence and the identification of as-yet-unclassified neutrophil-tropic strains raise concerns about the specificity of serological tests routinely used in ruminants and provide additional background for reconstructing the evolutionary history of species genetically related to A. phagocytophilum.

Detection of novel strains genetically related to Anaplasma platys in Tunisian one-humped camels (Camelus dromedarius)

“…Overall, 66 out of 226 camels (29.2%) were seropositive. The discrepancy between molecular and serological tests could be explained by cross-reactivity of the antigen used in serology with anti-cytoplasmic antibodies, as well as with other autoimmune antibodies and/or with antibodies related to other Anaplasma species closely related to those of A. phagocytophilum [17,18,45]. Notably, previous studies reported a great degree of cross-reactivity in serological tests between Anaplasma species [46][47][48].…”

“…In particular, all Anaplasma sp. Tunisian strains were closely related to A. platys strains isolated from Chinese goats and to Italian strains isolated from goats and cattle [10,17].…”

“…Similarly, comparisons based on 763 bp of the 16S rRNA gene highlighted a similarity of 99.3% with strains BovineCaprine1 and Caprine2 found on Italian cattle and goats (GenBank accession numbers KC335220-KC335222) and classified as Anaplasma sp. strains closely related to A. platys [17].…”

“…Indeed, infection with A. centrale induces long-lasting protective immunity in In Sicily, Italy, strains closely related to A. platys have been detected in neutrophils of cattle, sheep and goats [17] and in platelets of cats [18]. Based on genetic analyses using 16S rRNA and groEL genes, these strains revealed very high levels of nucleotide identity with canine A. platys strains (99% and 92%-93% identities with A. platys 16S rRNA and groEL genes, respectively) and were placed in a distinct monophyletic cluster closely related to A. platys sequences [17,18].…”

Apport de la qPCR au dépistage des infections des ruminants par des Anaplasmataceae : étude de cas au Pays Basque et en Corse

“…A. centrale est décrite chez des bovins en Sicile et chez des chevrettes en Espagne (Ceci et al 2014), alors qu'A. bovis est rapportée en Italie et en Espagne (Ceci et al 2014 ;Zobba et al 2014). …”