Generation of Monoclonal Antibodies Specific for the Recombinant Gn, N and Nss Proteins of Rift Valley Fever Virus
Arthropod-Borne Animal Diseases Research
2012 Annual Report
1a.Objectives (from AD-416):
To generate multiple monoclonal antibodies against RVFV antigens Gn, N and NSs that can be used in (a) Research and development of antigen detection and quantitation assays; (b) Reagents for other serological assays; (c) Research to characterize the immunological response to RVFV; and (d) Technical transfer to commercial firms engaged in development of diagnostic and vaccine projects.
1b.Approach (from AD-416):
Rift Valley fever virus (RVFV) is a zoonotic insect transmitted virus endemic to Africa and the Arabian Peninsula. Virus infection causes abortions and high mortality in newborn ruminants. Humans can become infected through handling infected animals and animal products. Severe infections can include ocular disease, meningoencephalitis, or hemorrhagic fever with an overall case fatality rate of <1. Panels of monoclonal antibodies are needed to facilite development of safe diagnostic assays. An anti-recombinant RVFV- nucleocapsid (N) polyclonal antibody was produced by ABADRU to develop an immunohistochemical (IHC) assay. Multiple ELISA assays have been developed based on a mouse anti-RVF MP-12 vaccine strain polyclonal antibody. A robust set of capture and detect monoclonal antibodies will be necessary to continue development of these assays and to make reagents available for international standardization of diagnostic tests and potential further test kit development (commercialization). Once validated and approved by national regulatory agencies, these reagents and assays will be useful to national laboratories as initial diagnostic tests (and validated against virus isolation). These assay reagents could be safely produced and distributed to regional diagnostic laboratories, thus providing capacity for early detection of RVFV in suspected ruminant samples.
The specific objective of this project is to generate monoclonal antibodies to Rift Valley fever virus antigens. The two most important sub-objectives re to.
1)generate matched pair candidates of antibodies specific for RVFV detection (Np protein) and.
2)antibodies specific for viral surface proteins for use as serological assay positive controls, and/or as capture–reagents. Other antibodies (such as antibodies specific for the nonstructural proteins will be useful in developing assays for the differentiation of vaccinated from infected animals. The project was delayed due to time required to acquire USDA APHIS permits. The permits have been granted and a project plan has been finalized. Immunizations of mice will begin in July 2012.