Rift Valley fever virus detection in susceptible hosts with special emphasis in insects

Area of Science:

• Veterinary Virology
• Medical Entomology
• Molecular Biology

Background:

• Rift Valley fever phlebovirus (RVFV) is an emerging arbovirus causing significant disease in livestock and humans.
• Accurate diagnostic tools for RVFV detection in various hosts are essential for disease control and research.
• Immunohistochemistry offers a valuable method for pathogen detection in tissue samples.

Purpose of the Study:

• To compare the immunohistological utility of various antibodies against RVFV epitopes.
• To evaluate RVFV detection in diverse host tissues, including mammals, insects, and cell lines.
• To identify optimal antibodies for RVFV diagnosis and research applications.

Main Methods:

• Testing of monoclonal and polyclonal antibodies against RVFV nucleoprotein, glycoproteins, and non-structural proteins.
• Application of immunohistochemistry on tissue samples from sheep, mosquitoes (Culex quinquefasciatus, Aedes aegypti), mice, Drosophila melanogaster, and C6/36 cells.
• Assessment of antibody cross-reactivity in non-infected specimens.

Main Results:

• RVFV nucleoprotein was prominently detected in mammal and mosquito tissues.
• Glycoproteins were exclusively detected in fruit fly tissues.
• Antibodies against non-structural proteins showed limited reactivity in mosquito salivary glands and cell lines.
• Cross-reactivity was observed in some antibodies, emphasizing the need for controls.

Conclusions:

• Antibodies targeting RVFV nucleoproteins are effective for detection in mammals.
• Antibodies targeting RVFV glycoproteins are useful for detection in insects.
• These validated antibodies enhance RVFV detection capabilities for diagnostic and research purposes.
• Careful interpretation and use of controls are critical due to observed cross-reactivity.