Bright signals. Comparison in exposure time and image quality in pictures captured from frozen tissue sections stained with biotinylated antibody + StreptaClick-HRP Multiplex IHC kit (left panel, exposure time 50 ms, x10 objective) or directly conjugated antibody (right panel, exposure time 700 ms, x10 objective). Antibodies: biotin-conjugated anti-CD4, clone GK1.5, dilution 1:400 (1.25 µg/ml) and AlexaFluor488-conjugated anti-CD4, clone GK1.5, dilution 1:100 (5 µg/ml). Tissue: mouse spleen.