Human influenza A is one of two influenza virus types that cause seasonal epidemics of disease (known as flu season) almost every winter in the United States. Influenza A viruses are the only influenza viruses known to cause flu pandemics (i.e., global epidemics of flu disease). (Source.)
CDC has discovered a series of human monoclonal antibodies (mAbs) that target hemagglutinin (HA), one of two proteins found on the surface of influenza A viruses. The mAbs are influenza virus subtype specific, broadly binding within a subtype, and broadly cross-reactive across influenza subtypes (group 1 and 2). CDC has obtained normal donor peripheral blood mononuclear cells (PBMCs) and purified B cells from a commercial source and sorted these cells based on influenza HA binding activity. The V(D)J genes of HA reactive B cells were then single-cell sequenced and cloned to produce recombinant mAbs for further characterization.
CDC has screened the mAbs produced from these studies by ELISA to confirm antigen specificity and approximate breadth of reactivity. Some mAbs were tested for antiviral activity in HA inhibition assays and a small number were screened by bio-layer interferometry to determine their epitope binding profile. CDC ha additional protection studies in mouse and/or ferret models underway to understand the technology’s potential to act as a prophylactic, therapeutic, and diagnostic.