Rhipicephalus microplus lipocalins (LRMs): Genomic identification and analysis of the bovine immune response using in silico predicted B and T cell epitopes
MetadataShow full item record
The attachment to host skin by Rhipicephalus microplus larvae induces a series of physiological events at the attachment site. The host-parasite interaction might induce a rejection of the larvae, as is frequently observed in Bos taurus indicus cattle, and under certain conditions in Bos taurus taurus cattle. Ticks deactivate the host rejection response by secreting specific proteins and lipids that play an essential role in manipulation of the host immune response. The available genomic information on the R. microplus tick was mined using bioinformatics approaches to identify R. microplus lipocalins (LRMs). This in silico examination revealed a total of 12 different putative R. microplus LRMs (LRM1-LRM12). The identity of the LRM family showed high sequence variability: from 6% between LRM7 and LRM8 to 55.9% between LRM2 and LRM6. However, the three-dimensional structure of the lipocalin family was conserved in the LRMs. The B and T cell epitopes in these lipocalins were then predicted, and six of the LRMs (5, 6, 9, 10, 11 and 12) were used to examine the host immune interactions with sera and peripheral blood mononuclear cells (PBMCs) collected from tick-susceptible and tick-resistant cattle challenged with R. microplus. On days 28-60 after tick infestation, the anti-LRM titres were higher in the resistant group compared with the susceptible cattle. After 60. day, the anti-LRM titres (except LRM9 and LRM11) decreased to zero in the sera of both the tick-resistant and tick-susceptible cattle. Using cell proliferation assays, the PBMCs challenged with some of the predicted T cell epitopes (LRM1_T1, T2; LRM_T1, T2 and LRM12_T) exhibited a significantly higher number of IFN-?-secreting cells (Th1) in tick-susceptible Holstein-Friesians compared with tick-resistant Brahman cattle. In contrast, expression of the Th2 cytokine (IL-4) was lower in Holstein-Friesians cattle compared with Brahman cattle. Moreover, this study found that LRM6, LRM9 and LRM11 play important roles in the mechanism by which R. microplus interferes with the host's haemostasis mechanisms. © 2013 Australian Society for Parasitology Inc.
Showing items related by title, author, creator and subject.
Comparative microarray analysis of Rhipicephalus (Boophilus) microplus expression profiles of larvae pre-attachment and feeding adult female stages on Bos indicus and Bos taurus cattleRodriguez-Valle, M.; Lew-Tabor, A.; Gondro, C.; Moolhuijzen, Paula; Vance, M.; Guerrero, F.; Bellgard, M.; Jorgensen, W. (2010)Background: Rhipicephalus (Boophilus) microplus is an obligate blood feeder which is host specific to cattle. Existing knowledge pertaining to the host or host breed effects on tick transcript expression profiles during ...
Immunological profiles of Bos taurus and Bos indicus cattle infested with the cattle tick, Rhipicephalus (Boophilus) microplusPiper, E.; Jonsson, N.; Gondro, C.; Lew-Tabor, A.; Moolhuijzen, Paula; Vance, M.; Jackson, L. (2009)The cattle tick, Rhipicephalus (Boophilus) microplus, is a major threat to the improvement of cattle production in tropical and subtropical countries worldwide. Bos indicus cattle are naturally more resistant to infestation ...
Differential recognition by tick-resistant cattle of the recombinantly expressed Rhipicephalus microplus serine protease inhibitor-3 (RMS-3)Rodriguez-Valle, M.; Vance, M.; Moolhuijzen, Paula; Tao, X.; Lew-Tabor, A. (2012)Rhipicephalus microplus is an important bovine ectoparasite, widely distributed in tropical and subtropical regions of the world causing large economic losses to the cattle industry. Its success as an ectoparasite is ...