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

Mouse lymph node stromal cells.

This monoclonal antibody is aseptically packaged and formulated in 0.01 M phosphate buffered saline (150 mM NaCl) PBS pH 7.2 - 7.4 with no carrier protein, potassium, calcium or preservatives added.

Liquid

This antibody may be stored sterile as received at 2-8°C for up to one month. For longer term storage, aseptically aliquot in working volumes without diluting and store at -80°C. Avoid Repeated Freeze Thaw Cycles.

Research Use Only

2 – 8° C Wet Ice

FA,
IHC,
IP,
WB,
FC

MECA-79 reacts with a family of sialomucins known collectively as peripheral node addressin (PNAd). MECA-79 recognizes O-glycans containing 6-sulfo N-acetylglucosamine in the extended core 1 structure.

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.

In mice, PNAd staining is detected on all high endothelial venules (HEV) in peripheral lymph nodes with intense cytoplasmic as well as luminal and abluminal cell surface reactivity. MECA-79 stains peripheral lymph nodes, some segments of mesenteric lymph nodes, the abluminal aspect of high endothelial cells (HEC) in Peyer’s patches, and postcapillary venules of inflamed non-lymphoid tissues. In humans, MECA-79 binds to HEC from tonsil.

CD62L

Q64311

1 Uchimura K, Rosen SD. Trends Immunol. 27(12):559-565. 2006.
2 Streeter PR, Rouse BT, Butcher EC. J Cell Biol. 107(5):1853-1862. 1988.
3 Yeh JC, Hiraoka N, Petryniak B, et al. Cell. 105(7):957-969. 2001.
4 Kawashima H, Petryniak B, Hiraoka N, et al. Nat Immunol. 6(11):1096-1104. 2005.
5 Uchimura K, Gauguet JM, Singer MS, et al. Nat Immunol. 6(11):1105-1113. 2005.
6 Hemmerich S, Butcher EC, Rosen SD. J Exp Med. 180(6):2219-2226. 1994.
7 Rosen SD, Tsay D, Singer MS, et al. Am J Pathol. 166(3):935-944. 2005.