The MEL-14 monoclonal antibody (mAb) reacts with CD62L (L-Selectin), a lymphocyte homing receptor that mediates initial cell adhesion interactions between circulating blood leukocytes and vascular endothelium. CD62L may also play a role in circulating mononuclear leukocyte extravasation at sites of inflammation. The MEL-14 mAb is expressed on most peripheral leukocytes. Relative levels of CD62L expression are often used in conjunction with other markers to distinguish naive T cells from antigen experienced T cells. The MEL-14 mAb blocks binding of lymphocytes to peripheral lymph node HEV and interferes with the migration of lymphocytes into peripheral lymph nodes in vitro. MEL-14 also inhibits binding of neutrophils to lymph node venules. Other applications of the MEL-14 mAb include immunoprecipitation, immunostaining for flow cytometry, complement mediated cytodepletion, and immunohistochemical staining.