Immunofluorescent detection in the ovary of host antibodies against a secretory ferritin injected into female Haemaphysalis longicornis ticks

• Published in: Parasitology international Vol. 67; no. 2; pp. 119 - 122
• Main Authors: Galay, Remil Linggatong, Matsuo, Tomohide, Hernandez, Emmanuel Pacia, Talactac, Melbourne Rio, Kusakisako, Kodai, Umemiya-Shirafuji, Rika, Mochizuki, Masami, Fujisaki, Kozo, Tanaka, Tetsuya
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.04.2018
• Subjects: Animals; Anti-tick vaccine; antibodies; Antibodies - administration & dosage; Antibodies - immunology; control methods; egg production; eggs; Female; females; Ferritin; Ferritins - immunology; Ferritins - metabolism; fluorescence; fluorescent antibody technique; Fluorescent Antibody Technique - methods; genes; Haemaphysalis longicornis; hatching; Host antibody; Host-Parasite Interactions; immunoglobulin G; Immunoglobulin G - administration & dosage; Immunoglobulin G - immunology; oocytes; Oocytes - immunology; Oocytes - ultrastructure; Ovary - cytology; Ovary - immunology; Ovary - ultrastructure; oviposition; pesticide application; Rabbits; tick control; Tick Control - methods; tick-borne diseases; Ticks; Ticks - anatomy & histology; Ticks - immunology; vaccination; vaccines; Anti-tick vaccine; Host antibody; Ticks; Ferritin
• ISSN: 1383-5769; 1873-0329; 1873-0329
• DOI: 10.1016/j.parint.2017.10.006

Due to the continuous threat of ticks and tick-borne diseases to human and animal health worldwide, and the drawbacks of chemical acaricide application, many researchers are exploring vaccination as an alternative tick control method. Earlier studies have shown that host antibodies can circulate in the ticks, but it has not been confirmed whether these antibodies can be passed on to the eggs. We previously reported that ticks infesting rabbits immunized with a recombinant secretory ferritin of Haemaphysalis longicornis (HlFER2) had reduced egg production and hatching. Here we attempted to detect the presence of antibodies against HlFER2 in the ovary and eggs of female ticks through immunofluorescent visualization. Purified anti-HlFER2 antibodies or rabbit IgG for control was directly injected to engorged female H. longicornis. Ovaries and eggs after oviposition were collected and prepared for an indirect immunofluorescent antibody test. Positive fluorescence was detected in ovaries one day post-injection of anti-HlFER2 antibodies. Through silencing of Hlfer2 gene, we also determined whether the injected antibodies can specifically bind to native HlFER2. Immunofluorescence was observed in the oocytes of dsLuciferase control ticks injected with anti-HlFER2 antibodies, but not in the oocytes of Hlfer2-silenced ticks also injected with anti-HlFER2 antibodies. Our current findings suggest that host antibodies can be passed on to the oocytes, which is significant in formulating a vaccine that can disrupt tick reproduction. [Display omitted] •Purified antibodies were directly injected into engorged female ticks.•Fluorescence was seen in oocytes 1 d post-injection of anti-HlFER2 antibodies.•No fluorescence was seen in oocytes of gene silenced ticks injected with antibodies.