Anti-Mouse/Human PNAd (Clone MECA-79) - Purified No Carrier Protein (P451-GRP)

MECA-79 antibody and L-selectin recognize the same family of sialomucins known collectively as peripheral node addressin (PNAd), with MECA-79 staining ligands for L- selectin expressed by high endothelial venules (HEVs)1. The MECA-79 epitope consists of a 6-sulfo N-acetyl-lactosamine modification of the extended core-1 branch that overlaps with the sialyl 6-sulfo Lewis X at its terminus. Binding requires GlcNAc-6 sulfation but not sialylation and/or fucosylation. MECA-79 stains lymph node HEVs and blocks L-selectin-dependent lymphocyte attachment in vitro and in vivo in mouse models2. In vitro, MECA-79 blocks normal lymphocytes and a peripheral lymph node-specific lymphoma from binding to peripheral lymph node HEV2. In vivo, MECA-79 inhibits normal lymphocyte homing to peripheral lymph nodes. Additionally, MECA-79 detects HEVs in lymph nodes of HEV-like vessels at the sites of chronic inflammation, where PNAd + vessels are induced, and staining of these vessels corresponds to functional L- selectin ligands1. Furthermore, MECA-79 antibody treatment reduces lymphocyte adhesion to GlyCAM-1 from wildtype mouse HEV3. MECA-79 was generated by immunizing a Wistar rat with lymphocytes released from pooled axillary, brachial, inguinal, and mesenteric lymph nodes of BALB/c mice2. Spleen cells from immune animals were fused with mouse myeloma Sp2/0 to create hybridomas, which were screened by immunofluorescence for an antibody that selectively stains peripheral lymph node HEV. MECA-79 is IgM.