Figure 1

Anti-CD152 derived from site-directed in vitro immunization exhibits specific binding towards human CD152 expressed both as a recombinant protein as well as a cell surface receptor. Panel A summarizes specific responses of PBMC's from five subjects receiving primary Ag stimulation alone (Nil) or from PBMC's treated with the indicated regimen. Bars indicate the median value of all subjects analyzed. Filled triangles represent specific frequencies of individual PBMC's. Original data can be retrieved from Additional File 1. Panel B illustrates a representative ELISA reactivity profile of culture supernatant. Diluted supernatants were tested in duplicate with 100 μL added to each well. Deviation between duplicate was less than 10% for any reported value. Panel C represents immunofluorescent staining of mitogen-activated CD3⁺ T cells (right thick peaks). PBMCs were isolated from normal blood donors and stimulated with indicated mitogens for 72 h to induce CD152 expression. Expression of mAb-recognized epitope was verified in gated CD3 population by flow cytometry. Data represent one experiment from three different normal subjects. Appropriate isotype controls were used for all Abs. The basal fluorescence obtained with the use of isotype control (IgG4λ myeloma protein) is indicated by the left thin peaks.