A cell based assay to quantify the titer of circulating Ebola glycoprotein (GP) antibodies that trigger antibody-dependent cell-mediated cytotoxicity (ADCC).
Ebola virus disease (EVD) is an acute illness with a fatality rate of approximately 50%. There are no available treatments or vaccines for EVD, though a number of immune therapies, blood products, and potential vaccines are being evaluated. Antibody-dependent cell-mediated cytotoxicity (ADCC) is used to measure the amounts of circulating antibodies that stimulate cell-mediated cytotoxicity. Current ADCC assays on the market are not specific to EVD and require the user to infect the target cells with a plasmids expressing Ebola proteins. More streamlined methods of screening and validating potential therapies for EVD are needed to help bring new therapies to the market quickly.
Emory inventors generated an Ebola specific antibody-dependent cell-mediated cytotoxicity (ADCC) assay. The Ebola ADCC assay includes a target cell line that stably expresses the Ebola virus glycoprotein (EBOV GP) under a tetracycline-controlled promoter, eliminating the need to transfect target cells with Ebola protein expressing plasmids every time the assay is to be performed. The target cells also express the luciferase gene as a means of measuring their killing. Target cell death is measured by loss of relative luciferase units. The Ebola ADCC Assay has been validated using plasma samples from human healthy control donors, or donors who carried antibodies to EBOV GP in their blood after receiving prime-boost Ebola vaccination and with commercially available anti-EBOV GP monoclonal antibodies.
The Ebola ADCC assay has been validated with commercially available antibodies and with post Ebola vaccination plasma samples.
Publication: Singh, K. et al. (2018). Journal of Immunological Methods, 460, 10-16.