Anti-AL4 antibodies are used in antigen-specific immunodetection in biological samples. The target AL4 is a known alias name of the protein G antigen 7, encoded by the GAGE7 gene in humans. This 117-amino acid residue protein is a member of the GAGE protein family. In terms of tissue expression, it is reported to be expressed in some prostate cancer tissues but not in normal prostate tissue.