Schematic representation of the production of Env183/A2 MAb. (A) Synthesis of HLA-A2 complexes, mouse immunization, B-cell selections, and characterization of specific antibody production (detailed in Materials and Methods). The table shows the total number of screened hybridomas and their specificities. (B) Histograms representing the different staining profiles of B-cell hybridoma supernatants. T2 cells were pulsed with 1 μM (each) Env183-91 peptide or influenza A virus matrix peptide at positions 58 to 66 (Flu M158-66) and then incubated with 50 μl of hybridoma supernatant followed by washing and incubation with anti-mouse IgG-Alexa Fluor 488 for 30 min. Cells were washed and analyzed with flow cytometry. Three different profiles (negative, specific for HLA-A2 molecules, and specific for the Env183/A2 complex) are represented. Data show representative FACS profiles.