CD3 molecule can form a composite receptor molecule with T cell surface antigen recognition receptor (TCR). It is the main recognition unit for T cell to recognize antigen and has the function of stabilizing TCR structure and transmitting activation signal.
CD3 is mainly used for diagnosis of T cell or NK cell lymphoma. It is highly sensitive and specific to T lymphocytes. It is not expressed on the surface of B lymphocytes. CD3 shows negative in a small number of T lymphocyte lymphomas such as large anaplastic. Cell lymphoma, pleomorphic lymphoma, etc.