Identification of Genes Encoding Cement-Like Antigens Expressed in the Salivary Glands of Haemaphysalis longicornis

Abstract

ABSTRACT. A cDNA expression library from the salivary glands of hard tick, Haemaphysalis longicornis, was constructed. Immunoscreening was performed using sera of the rabbit repeatedly infested with ticks and seventeen positive clones were obtained. A BLASTP search suggested that 8 sequences matched with that of hypothetical H. longicornis sequence and one clone encoded HL35 antigen U from the same tick species. Eight of 17 gave no match to any sequence reported in the database. The proteins expected from these novel sequences possess common characteristics with cement proteins which assist ticks in their attachment to the host during blood feeding. The expression of these genes in salivary glands was confirmed by RT-PCR. Four of the 8 sequences showed to be upregulated upon blood feeding. These immunodominant antigens are of particular interest as candidates for future cement protein based-tick vaccine.

Characterization of a glycine-rich protein from Rhipicephalus microplus: tissue expression, gene silencing and immune recognition

“…Therefore, different tick species seem to overexpress some GRPs upon blood repletion, as could be seen for rmgrp . High expression levels were also presented by rmgrp in larvae, what may be consistent with a function of RmGRP in the cement cone formation (Harnnoi et al 2006; Bullard et al 2016 b ). Conversely, it must be emphasized that the cement cone tends to be structured until 24 h of fixation (Bennington, 1978), therefore high levels of mRNA transcription to cement proteins are not likely to be present in partially and fully engorged adult females.…”

Transmission-Blocking Vaccines: Focus on Anti-Vector Vaccines against Tick-Borne Diseases

“…Study from Chai et al ( 2009 ) has identified 12 unique cDNA sequences in a phage library that encode putative immunodominant antigens in Haemaphysalis longicornis . Harnnoi et al ( 2006 ) have identified genes encoding cement-like antigens in H. longicornis . These cement-like proteins in H. longicornis were upregulated upon feeding (Harnnoi et al 2006 ).…”

“…Harnnoi et al ( 2006 ) have identified genes encoding cement-like antigens in H. longicornis . These cement-like proteins in H. longicornis were upregulated upon feeding (Harnnoi et al 2006 ). HISP, a cubilin-related serine proteinase was identified in H. longicornis (Miyoshi et al 2004 ).…”