scholarly journals Sialomucin CD34 is the major L-selectin ligand in human tonsil high endothelial venules.

1995 ◽  
Vol 131 (1) ◽  
pp. 261-270 ◽  
Author(s):  
K D Puri ◽  
E B Finger ◽  
G Gaudernack ◽  
T A Springer
Keyword(s):  
Complex Mixture ◽  
Lymphocyte Homing ◽  
High Endothelial Venules ◽  
Human Tonsil ◽  
Hematopoietic Cell Line ◽  
Selectin Ligands ◽  
Selectin Ligand ◽  
Peripheral Node ◽  
Ligand Activity

Peripheral node addressin (PNAd) is a complex mixture of glycoproteins with L-selectin ligand activity that functions in lymphocyte homing. We have investigated the contribution of the sialomucin CD34 relative to other components of PNAd in lymphocyte tethering and rolling in in vitro laminar flow assays. PNAd was isolated with MECA-79 mAb-Sepharose from tonsillar stroma, and the CD34 component (PNAd,CD34+) and CD34-negative component (PNAd,CD34-) separated on CD34 mAb-Sepharose. Lymphocytes on the PNAd,CD34- fraction tether less efficiently, roll faster and are less resistant to shear detachment than on PNAd. The PNAd,CD34+ fraction constitutes about half the total functional activity. These studies show that CD34 is a major functional component of PNAd. Ligand activity in both the PNAd,CD34+ and PNAd,CD34- fractions is expressed on mucin-like domains, as shown with O-sialoglycoprotease. The CD34 component of PNAd has about four times higher tethering efficiency than total tonsillar CD34. CD34 from spleen shows no lymphocyte tethering. Although less efficient than the PNAd,CD34+ fraction from tonsil, CD34 from the KG1a hematopoietic cell line is functionally active as an L-selectin ligand despite lack of reactivity with MECA-79 mAb, which binds to a sulfation-dependent epitope. All four forms of CD34 are active in binding to E-selectin. KG1a CD34 but not spleen CD34 are active as L-selectin ligands, yet both lack MECA-79 reactivity and possess E-selectin ligand activity. This suggests that L-selectin ligands and E-selectin ligands differ in more respects than presence of the MECA-79 epitope.

scholarly journals A Novel Endothelial L-Selectin Ligand Activity in Lymph Node Medulla That Is Regulated by α(1,3)-Fucosyltransferase-IV

2003 ◽  
Vol 198 (9) ◽  
pp. 1301-1312 ◽  
Author(s):  
Christine M'Rini ◽  
Guiying Cheng ◽  
Colleen Schweitzer ◽  
Lois L. Cavanagh ◽  
Roger T. Palframan ◽  
...  
Keyword(s):  
Mrna Level ◽  
Surrogate Marker ◽  
High Endothelial Venules ◽  
Cell Homing ◽  
Selectin Ligands ◽  
Peripheral Lymph ◽  
T Cell Homing ◽  
Selectin Ligand ◽  
Peripheral Node ◽  
Ligand Activity

Lymphocytes home to peripheral lymph nodes (PLNs) via high endothelial venules (HEVs) in the subcortex and incrementally larger collecting venules in the medulla. HEVs express ligands for L-selectin, which mediates lymphocyte rolling. L-selectin counterreceptors in HEVs are recognized by mAb MECA-79, a surrogate marker for molecularly heterogeneous glycans termed peripheral node addressin. By contrast, we find that medullary venules express L-selectin ligands not recognized by MECA-79. Both L-selectin ligands must be fucosylated by α(1,3)-fucosyltransferase (FucT)-IV or FucT-VII as rolling is absent in FucT-IV+VII−/− mice. Intravital microscopy experiments revealed that MECA-79–reactive ligands depend primarily on FucT-VII, whereas MECA-79–independent medullary L-selectin ligands are regulated by FucT-IV. Expression levels of both enzymes paralleled these anatomical distinctions. The relative mRNA level of FucT-IV was higher in medullary venules than in HEVs, whereas FucT-VII was most prominent in HEVs and weak in medullary venules. Thus, two distinct L-selectin ligands are segmentally confined to contiguous microvascular domains in PLNs. Although MECA-79–reactive species predominate in HEVs, medullary venules express another ligand that is spatially, antigenically, and biosynthetically unique. Physiologic relevance for this novel activity in medullary microvessels is suggested by the finding that L-selectin–dependent T cell homing to PLNs was partly insensitive to MECA-79 inhibition.

Sulphated endothelial ligands for L-selectin in lymphocyte homing and inflammation

2003 ◽  
Vol 31 (2) ◽  
pp. 313-317 ◽  
Author(s):  
A. van Zante ◽  
S.D. Rosen
Keyword(s):  
Monoclonal Antibody ◽  
Endothelial Cells ◽  
Lymphoid Tissues ◽  
Lymphocyte Homing ◽  
High Endothelial Venules ◽  
Selectin Ligands ◽  
Peripheral Lymph ◽  
Selectin Ligand ◽  
Endothelial Ligands ◽  
Peripheral Node

Lymphocytes from the blood home to secondary lymphoid tissues through a process of tethering, rolling, firm adhesion and transmigration. Tethering and rolling of lymphocytes is mediated by the interaction of L-selectin on lymphocytes with sulphated ligands expressed by the specialized endothelial cells of high endothelial venules (HEVs). The sulphate-dependent monoclonal antibody MECA79 stains HEVs in peripheral lymph nodes and recognizes the complex of HEV ligands for L-selectin termed peripheral node addressin. High endothelial cell GlcNAc-6-sulphotransferase/L-selectin ligand sulphotransferase is a HEV-expressed sulphotransferase that contributes to the formation of the MECA79 epitope and L-selectin ligands on lymph node HEVs. MECA79-reactive vessels are also common at sites of chronic inflammation, suggesting mechanistic parallels between lymphocyte homing and inflammatory trafficking.

scholarly journals Lymphocyte–HEV Interactions in Lymph Nodes of a Sulfotransferase-deficient Mouse

2003 ◽  
Vol 198 (9) ◽  
pp. 1289-1300 ◽  
Author(s):  
Annemieke van Zante ◽  
Jean-Marc Gauguet ◽  
Annette Bistrup ◽  
Durwin Tsay ◽  
Ulrich H. von Andrian ◽  
...  
Keyword(s):  
Lymph Nodes ◽  
Dependent Manner ◽  
Deficient Mouse ◽  
Wild Type ◽  
Lymphocyte Homing ◽  
High Endothelial Venules ◽  
Blocking Antibody ◽  
Selectin Ligands ◽  
Deficient Mice

The interaction of L-selectin expressed on lymphocytes with sulfated sialomucin ligands such as CD34 and GlyCAM-1 on high endothelial venules (HEV) of lymph nodes results in lymphocyte rolling and is essential for lymphocyte recruitment. HEC-GlcNAc6ST–deficient mice lack an HEV-restricted sulfotransferase with selectivity for the C-6 position of N-acetylglucosamine (GlcNAc). HEC-GlcNAc6ST−/− animals exhibit faster lymphocyte rolling and reduced lymphocyte sticking in HEV, accounting for the diminished lymphocyte homing. Isolated CD34 and GlyCAM-1 from HEC-GlcNAc6ST−/− animals incorporate ∼70% less sulfate than ligands from wild-type animals. Furthermore, these ligands exhibit a comparable reduction of the epitope recognized by MECA79, a function-blocking antibody that reacts with L-selectin ligands in a GlcNAc-6-sulfate–dependent manner. Whereas MECA79 dramatically inhibits lymphocyte rolling and homing to lymph nodes in wild-type mice, it has no effect on HEC-GlcNAc6ST−/− mice. In contrast, in vitro rolling on purified GlyCAM-1 from HEC-GlcNAc6ST−/− mice, although greatly diminished compared with that on the wild-type ligand, is inhibited by MECA79. Our results demonstrate that HEC-GlcNAc6ST contributes predominantly, but not exclusively, to the sulfation of HEV ligands for L-selectin and that alternative, non-MECA79–reactive ligands are present in the absence of HEC-GlcNAc6ST.

N-acetylglucosamine-6-O-sulfotransferases 1 and 2 cooperatively control lymphocyte homing through L-selectin ligand biosynthesis in high endothelial venules

2005 ◽  
Vol 6 (11) ◽  
pp. 1096-1104 ◽  
Author(s):  
Hiroto Kawashima ◽  
Bronislawa Petryniak ◽  
Nobuyoshi Hiraoka ◽  
Junya Mitoma ◽  
Valerie Huckaby ◽  
...  
Keyword(s):  
Lymphocyte Homing ◽  
High Endothelial Venules ◽  
Selectin Ligand

scholarly journals L-Selectin Ligands That Are O-glycoprotease Resistant and Distinct from MECA-79 Antigen are Sufficient for Tethering and Rolling of Lymphocytes on Human High Endothelial Venules

1998 ◽  
Vol 140 (3) ◽  
pp. 721-731 ◽  
Author(s):  
Rachael A. Clark ◽  
Robert C. Fuhlbrigge ◽  
Timothy A. Springer
Keyword(s):  
In Vitro Assay ◽  
Lymphoid Tissues ◽  
Sialyl Lewisx ◽  
High Endothelial Venules ◽  
Vitro Assay ◽  
Tissue Sections ◽  
High Affinity ◽  
Selectin Ligands ◽  
Carbohydrate Ligands

During the process of lymphocyte recirculation, lymphocytes bind via L-selectin to sulfated sialyl-Lewisx (sLex)–containing carbohydrate ligands expressed on the surface of high endothelial venules (HEV). We have examined the expression of sLex on HEV using a panel of mAbs specific for sLex and sLex-related structures, and have examined the function of different sLex-bearing structures using an in vitro assay of lymphocyte rolling on HEV. We report that three sLex mAbs, 2F3, 2H5, and CSLEX-1, previously noted to bind with high affinity to glycolipid-linked sLex, vary in their ability to stain HEV in different lymphoid tissues and bind differentially to O-linked versus N-linked sLex on glycoproteins. Treatment of tissue sections with neuraminidase abolished staining with all three mAbs but slightly increased staining with MECA-79, a mAb to a sulfation-dependent HEV-associated carbohydrate determinant. Treatment of tissue sections with O-sialoglycoprotease under conditions that removed the vast majority of MECA-79 staining, only partially reduced staining with the 2F3 and 2H5 mAbs. Using a novel rolling assay in which cells bind under flow to HEV of frozen tissue sections, we demonstrate that a pool of O-sialoglycoprotease–resistant molecules is present on HEV that is sufficient for attachment and rolling of lymphocytes via L-selectin. This interaction is not inhibited by the mAb MECA-79. Furthermore, MECA-79 mAb blocks binding to untreated sections by only 30%, whereas the sLex mAb 2H5 blocks binding by ∼60% and a combination of MECA-79 and 2H5 mAb blocks binding by 75%. We conclude that a pool of O-glycoprotease-resistant sLex-like L-selectin ligands exist on human HEV that is distinct from the mucin-associated moieties recognized by MECA-79 mAb. We postulate that these ligands may participate in lymphocyte binding to HEV.

Differential requirements for the O-linked branching enzyme core 2 β1-6-N-glucosaminyltransferase in biosynthesis of ligands for E-selectin and P-selectin

Blood ◽  
2001 ◽  
Vol 97 (12) ◽  
pp. 3806-3811 ◽  
Author(s):  
Karen R. Snapp ◽  
Christine E. Heitzig ◽  
Lesley G. Ellies ◽  
Jamey D. Marth ◽  
Geoffrey S. Kansas
Keyword(s):  
Lymphoid Cells ◽  
Carbohydrate Binding ◽  
Th1 Cells ◽  
Branching Enzyme ◽  
Wild Type ◽  
Short Term ◽  
Regulation Of Expression ◽  
Selectin Ligands ◽  
Selectin Ligand

Selectins are carbohydrate-binding adhesion molecules that play important roles in control of leukocyte traffic. Glycosyltransferases involved in selectin ligand biosynthesis include the α1,3-fucosyltransferases FucT-VII and FucT-IV, one or more sialyltransferases, and at least one O-linked branching enzyme. Previous studies have shown that core 2 β1-6-N-glucosaminyltransferase (C2GlcNAcT-I; EC 2.4.1.102) is required for functional modification of PSGL-1, the leukocyte P-selectin ligand, but have been ambiguous on whether this enzyme is involved in E-selectin ligand formation. Using an attachment and rolling assay under defined shear flow in vitro, this study shows that C2GlcNAcT-I− lymphoid cells stably transfected with FucT-VII complementary DNA attach and roll well on E-selectin at 1.5 dynes/cm.2 Further, attachment and rolling on P-selectin of neutrophils is sharply reduced and that of short- term polarized Th1 cells is virtually abolished, with leukocytes from C2GlcNAcT-I−/− mice. In contrast, both neutrophils and Th1 cells from C2GlcNAcT-I−/− mice attach and roll as well as wild-type cells on E-selectin. These results show that C2GlcNAcT-I is selectively required for biosynthesis of ligands for P-selectin, but is not essential for at least some E-selectin ligands. Distinct requirements for C2GlcNAcT-I in the formation of ligands for E-selectin versus P-selectin represents a novel level of regulation of expression of selectin ligands and lymphocyte traffic.

The Nature of the P-Selectin Ligands on Sickle Cells.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 363-363
Author(s):  
Stephen H. Embury ◽  
Christine E. Baran ◽  
Colleen A. Hefner ◽  
Christi K. Seto ◽  
Neil M. Matsui
Keyword(s):  
Flow Cytometry ◽  
Sialic Acid ◽  
Transferrin Receptor ◽  
Cell Disease ◽  
Selectin Ligands ◽  
Selectin Ligand ◽  
Selectin Binding ◽  
Binding Determinants

Abstract Elucidation of the adhesive interactions that effect microvascular occlusion in sickle cell disease both increases our understanding of the pathophysiology of vasoocclusion and identifies molecular targets for the development of therapeutic interventions. Work from our laboratory has established that sickle RBC adhere to P-selectin on thrombin-activated endothelial cells and to immobilized, recombinant P-selectin in vitro (Matsui et al. Blood 98:1955, 2001) and that this adhesion can be inhibited by agents that block P-selectin (Matsui et al. Blood 100:3790, 2002). Based on these findings, we established that sickle RBC adherence to endothelial P-selectin has a substantial influence on microvascular blood flow in vivo and that blocking P-selectin enhances microvascular flow (Embury et al. Blood In Press). We reasoned that characterization of the cognate ligands for P-selectin ligand on sickle RBC could identify additional targets for therapeutic intervention. We had determined that that sickle RBC did not express the P-selectin ligand, P-selectin glycoprotein-1, but that membrane sialic acid is required for sickle RBC binding to P-selectin. Here we describe further characterization of the P-selectin binding determinants on sickle RBC membranes. We assessed the expression of sialyl Lewis X (sLeX) on sickle RBC using flow cytometry and the importance of sLeX expression to the rolling adhesion of sickle RBC to P-selectin in vitro. Using the monoclonal antibodies (mAb) HECA-452 and CSLEX-1 in flow cytometry we detected significant expression of sLeX on sickle RBC (p < 0.003 and p < 0.02, respectively) but not on non-sickle RBC (p < 0.07 and p < 0.3, respectively). Treatment of sickle RBC with sialidase caused a partial, dose dependant reduction of the level of detectable sLeX and of rolling adhesion to immobilized P-selectin (approximately 40% and 85%, respectively), which correlated positively. To assess the possible selective contribution of reticulocytes as a subset of higher sLeX expressing sickle RBC we employed dual label flow cytometry to determine whether sLeX and the transferrin receptor (CD71) are co-expressed. Using mAb YDJ1.2.2 for the transferrin receptor as a reticulocyte marker and CSLEX-1 showed that sLeX was expressed both on sickle reticulocytes and on older sickle RBC. Treatment of sickle RBC with O-sialoglycoprotein endopeptidase, which cleaves sialylated O-glycans, also reduced both their sLeX expression and rolling adhesion on P-selectin (approximately 30% and 65%, respectively). Treatment of sickle RBC with N-glycosidase F did not reduce sLeX or adhesion levels, trypsin treatment produced inconsistent effects, and phosphatidylinositol-specific phospholipase C caused a significant decrease in adhesion but not a significant reduction in sLex expression. These findings suggest that sickle RBC possess more than one type of glycoprotein as a ligand for P-selectin. We also used a solid-phase binding assay to detect a significant level of P-selectin binding to membrane lipids extracted from sickle RBC. Thus, the P-selectin binding determinants on sickle RBC include sialic acid, sLeX, O-linked glycans, PI-linked glycoproteins, and glycolipids. Each of these P-selectin ligands represents a potential target of new adhesion blocking drugs for the treatment of sickle cell disease.

E-Selectin Ligand Expression Increases with Progression of Myeloma and Induces Drug Resistance in a Murine Transplant Model, Which Is Overcome By the Glycomimetic E-Selectin Antagonist, GMI-1271

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 1805-1805 ◽  
Author(s):  
Alessandro Natoni ◽  
Theodore A.G. Smith ◽  
Niamh Keane ◽  
Silvia C. Locatelli-Hoops ◽  
Isabela Oliva ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Disease Progression ◽  
Cell Lines ◽  
Saline Control ◽  
Selectin Ligands ◽  
Ligand Expression ◽  
Selectin Ligand ◽  
Transplant Model

Abstract There is increasing evidence that E-selectin and its ligands play an important role in the progression of multiple myeloma (MM) and drug resistance. We reported that the sialyltransferase ST3GAL6 influences homing and survival in MM, and postulated that it may function in the synthesis of E-selectin ligands (Glavey et al Blood, 2014). We also found that a small subpopulation of cells (~ 5%) from MM cell lines express functional E-selectin ligands, which could be expanded under hypoxic conditions typical of the bone marrow (BM) microenvironment. These cells were identified by reactivity with an antibody (HECA452), which binds the same carbohydrate epitope required for binding to E-selectin. Rolling of MM1S cells on E-selectin was blocked by a small molecule glycomimetic antagonist to E-selectin (GMI-1271). Moreover, GMI-1271 significantly enhanced the anti-myeloma activity of bortezomib (BTZ) in an in vivo murine transplant model (Natoni et al Blood, 2014). We now extend these observations to obtain a more complete understanding of the role E-selectin plays in MM biology and chemotherapy resistance for its potential clinical relevance. The parental, heterogeneous MM cell lines MM1S and RPMI8226 (MM1Spar, RPMI8226par, respectively) were sequentially sorted to obtain cell lines highly enriched (>85% and 80%) for the expression of cell surface carbohydrates bound by HECA452, and designated MM1SHECA452 and RPMI8226HECA452. The cell lines could be passaged in vitro and were stable for enriched E-selectin ligand expression. In contrast to parental cells, both MM1SHECA452 and RPMI8226HECA452 showed strong binding to E-selectin in static adhesion assays. Both MM1SHECA452 and RPMI8226HECA452 exhibited strong rolling on E-selectin under shear stress. MM1Spar or RPMI8226par failed to roll well on E-selectin. The addition of GMI-1271 during culture conditions led to a marked reduction in adhesion of MM1SHECA452 and profoundly inhibited rolling on E-selectin of both HECA452 enriched MM cell lines. The significance of these in vitro findings was studied in vivo. MM1Spar or MM1SHECA452 cells were injected i.v. into SCID beige mice. Beginning 5 days post tumor injection, the survival impact of treatment with saline control, GMI-1271, BTZ or a combination of both was determined. Mice transplanted with MM1SHECA452 had more aggressive disease with significantly shorter survival compared to those transplanted with MM1Spar. In contrast to MM1Spar cells, mice engrafted with MM1SHECA452 demonstrated a marked resistance to BTZ treatment. Whereas GMI-1271 treatment alone had no impact on survival, the combination of GMI-1271 and BTZ led to a highly significant improvement in survival of MM1Spar engrafted mice (P=0.0363), and more importantly broke the resistance and restored the anti-myeloma activity of BTZ in MM1SHECA452 engrafted mice (P=0.0123) (figure 1). The number of peripheral blood (PB) human CD138+ cells was increased in MM1SHECA452-engrafted mice within 60 min following a single injection of GMI-1271, and persisted for at least 24 hours (2.37% v. 0.03%, p <0.001). This effect was consistent with GMI-1271 disrupting the tumor microenvironment and mobilizing MM1SHECA-452 cells from the BM niche. Given these findings we wished to see if samples from patients with MM express E-selectin ligands and whether higher levels are seen with disease progression. BM and/or PB were obtained following informed consent from patients with MM and plasma cells (CD38+/CD138+) were analyzed for E-selectin ligand expression by flow cytometry using the HECA452 antibody. To date all primary MM samples (n=25) contained HECA452-reactive cell populations (median 22%). A consistently higher proportion of circulating MM cells express HECA452 when compared with paired BM samples (n=14), with a median difference of 33% (Wilcoxon signed rank test, p=0.02). HECA452 expression of MM in PB was significantly higher (on average 40% higher) in samples taken at relapse vs. diagnosis, (unpaired t test, p = 0.0008) These data provide compelling evidence that E-selectin ligand bearing cells play an important role in disease progression and drug resistance in MM, and a strong rationale for clinical strategies incorporating GMI-1271 to improve patient outcome. Disclosures Smith: GlycoMimetics, Inc.: Employment. Locatelli-Hoops:GlycoMimetics, Inc.: Employment. Oliva:GlycoMimetics, Inc.: Employment. Fogler:GlycoMimetics, Inc.: Employment. Magnani:GlycoMimetics: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees. O'Dwyer:Celgene: Honoraria, Research Funding.

scholarly journals Podocalyxin-like protein is an E-/L-selectin ligand on colon carcinoma cells: comparative biochemical properties of selectin ligands in host and tumor cells

2009 ◽  
Vol 296 (3) ◽  
pp. C505-C513 ◽  
Author(s):  
Susan N. Thomas ◽  
Ronald L. Schnaar ◽  
Konstantinos Konstantopoulos
Keyword(s):  
Tumor Cell ◽  
Tumor Cells ◽  
Colon Carcinoma ◽  
Carcinoma Cells ◽  
Host Cells ◽  
High Endothelial Venules ◽  
Colon Carcinoma Cells ◽  
Selectin Ligands ◽  
Selectin Ligand ◽  
Selectin Binding

Selectins facilitate metastasis and tumor cell arrest in the microvasculature by mediating binding of selectin-expressing host cells to ligands on tumor cells. We recently identified CD44 variant isoforms as functional P-, but not E-/L-, selectin ligands on colon carcinoma cells. Furthermore, a ∼180-kDa sialofucosylated glycoprotein(s) mediated selectin binding in CD44-knockdown cells. Using immunoaffinity chromatography and tandem mass spectrometry, we identify podocalyxin-like protein (PCLP) as an alternative selectin ligand. Blot rolling and cell-free flow-based adhesion assays disclose that PCLP on LS174T colon carcinoma cells possesses E-/L-, but not P-, selectin binding activity. The selectin-binding determinants on LS174T PCLP are non-MECA-79-reactive sialofucosylated structures displayed on O-linked glycans, distinct from the MECA-79-reactive O-glycans on PCLP expressed by high endothelial venules, which is an L-selectin ligand. PCLP on CD44-knockdown LS174T cells exhibits higher HECA-452 immunoreactivity than PCLP on wild-type cells, suggesting that PCLP functions as an alternative acceptor for selectin-binding glycans. The enhanced expression of HECA-452 reactivity on PCLP from CD44-knockdown cells correlates with the increased avidity of PCLP for E- but not L-selectin. The novel finding that PCLP is an E-/L-selectin ligand on carcinoma cells offers a unifying perspective on the apparent enhanced metastatic potential associated with tumor cell PCLP overexpression and the role of selectins in metastasis.

scholarly journals Essential role of peripheral node addressin in lymphocyte homing to nasal-associated lymphoid tissues and allergic immune responses

2011 ◽  
Vol 208 (5) ◽  
pp. 1015-1025 ◽  
Author(s):  
Yukari Ohmichi ◽  
Jotaro Hirakawa ◽  
Yasuyuki Imai ◽  
Minoru Fukuda ◽  
Hiroto Kawashima
Keyword(s):  
T Cells ◽  
Immune Responses ◽  
Specific Ige ◽  
Treg Cells ◽  
Lymphoid Tissues ◽  
Lymphocyte Homing ◽  
Double Knockout ◽  
High Endothelial Venules ◽  
Peripheral Node

Nasal-associated lymphoid tissue (NALT) is a mucosal immune tissue that provides immune responses against inhaled antigens. Lymphocyte homing to NALT is mediated by specific interactions between lymphocytes and high endothelial venules (HEVs) in NALT. In contrast to HEVs in other mucosal lymphoid tissues, NALT HEVs strongly express peripheral node addressins (PNAds) that bear sulfated glycans recognized by the monoclonal antibody MECA-79. We investigated the role of PNAd in lymphocyte homing to NALT using sulfotransferase N-acetylglucosamine-6-O-sulfotransferase (GlcNAc6ST) 1 and GlcNAc6ST-2 double knockout (DKO) mice. The expression of PNAd in NALT HEVs was eliminated in DKO mice. Short-term homing assays indicated that lymphocyte homing to NALT was diminished by 90% in DKO mice. Production of antigen-specific IgE and the number of sneezes in response to nasally administered ovalbumin were also substantially diminished. Consistently, the NALT of DKO mice showed reduced production of IL-4 and increased production of IL-10 together with an increase in CD4+CD25+ regulatory T cells (Treg cells). Compared with the homing of CD4+CD25− conventional T cells, the homing of CD4+CD25+ Treg cells to NALT was less dependent on the L-selectin–PNAd interaction but was partially dependent on PSGL-1 (P-selectin glycoprotein ligand 1) and CD44. These results demonstrate that PNAd is essential for lymphocyte homing to NALT and nasal allergic responses.

Sign in / Sign up

Export Citation Format

Share Document