Anti-CD5 Antibody is a humanized monoclonal antibody targeting CD5 (also known as T1 or Leu-1). CD5 is a transmembrane glycoprotein primarily expressed on T cells and a subset of B1a cells, functioning as a negative regulator of T-cell receptor (TCR) and B-cell receptor (BCR) signaling. It plays a crucial role in maintaining immune tolerance and preventing autoimmune responses. This antibody is used to study the regulatory mechanisms of T-cell activation, develop targeted therapies for CD5-positive hematological malignancies (such as chronic lymphocytic leukemia and mantle cell lymphoma), or act as a novel immune checkpoint blockade to enhance anti-tumor immune responses by relieving immune inhibition.