PD-L1 is a checkpoint regulator in immune cells, it is expressed on immune or non-hematopoietic cells. Expression of the protein is seen during pregnancy where it has a role in suppressing the immune system. PD-L1 induces an inhibitory signal in activated T-cells and promotes T-cell apoptosis. It is overexpressed in a number of different cancers where it is believed to play a significant role in the cancer s ability to evade the immune system. Primary antibodies are available purified, or with a selection of fluorescent CF® Dyes and other labels. CF® Dyes offer exceptional brightness and photostability. Note: Conjugates of blue fluorescent dyes like CF®405S and CF®405M are not recommended for detecting low abundance targets, because blue dyes have lower fluorescence and can give higher non-specific background than other dye colors.