Description: The UCHL1 monoclonal antibody reacts with human CD45RO, a 180 kDa isoform of CD45. CD45RO is expressed by most thymocytes, activated memory T cells, granulocytes and monocytes. CD22 is a ligand for CD45RO. Expression of CD45RO and CD45RA is used commonly to discriminate subsets of peripheral T cells.