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At least 19 recordsLinked to original sources
PubMed1998

Characterization of cDNAs encoding a new family of tetraspanins from schistosomes--the Sj25 family.

The tetraspanins, also known as members of the transmembrane 4 superfamily (TM4SF), comprise an assemblage of surface antigens reported from mammalian and other vertebrate cells, from schistosomes, from fruit flies and from Caenorhabditis elegans. Tetraspanins are characterized by the presence of four hydrophobic domains, which are presumed to be membrane-spanning, and specific conserved motifs. A novel cDNA encoding a new tetraspanin, termed TE736 (tetraspanin 736), was isolated and characterized from the human blood fluke Schistosoma japonicum. Nucleotide and deduced amino acid sequences of the cDNA revealed that TE736 was similar to the previously characterized Sm23/Sj23/Sh23 species homologues and to Sj25/TM4 from schistosomes, and to other tetraspanins. Comparison of hydropathicity profiles of TE736, Sj25/TM4 and two novel tetraspanin-like sequences from S. mansoni showed that they contain four potential transmembrane domains like other tetraspanins. Sequence alignments showed there are four highly conserved, cysteine residues on the second predicted extracellular loop of TE736. A phylogenetic comparison of the relationship of approximately 30 tetraspanins from mammals and other groups revealed that TE736, Sj25/TM4 and the two sequences from S. mansoni formed an independent family of tetraspanins. We have termed these tetraspanins from schistosomes the Sj25 family. TE736 appeared to be encoded by a single gene and to be expressed in at least two life cycle stages of S. japonicum.

Amino Acid Sequence↗
PubMed1991

A new superfamily of lymphoid and melanoma cell proteins with extensive homology to Schistosoma mansoni antigen Sm23.

A novel cDNA clone termed R2 was isolated by subtractive hybridization of a cDNA library of phytohemagglutinin (PHA)/phorbol myristate acetate-stimulated Jurkat cells and by rescreening a cDNA library of PHA-stimulated peripheral blood lymphocytes. It hybridizes to a single mRNA species of about 2.2 kb, which is inducible in lymphoid cells and codes for a protein of 267 amino acids which contains four potential transmembrane domains. A computer-aided comparison showed strong homology to four other membrane proteins, the pan B cell marker CD37, the pan leukocyte marker CD53, the melanoma antigen ME491 and, surprisingly, the Schistosoma mansoni antigen Sm23. The four human proteins share a number of additional similarities in their overall structure. These include identical spacing of the transmembrane domains, similar hydrophobicity plots, possible N-linked glycosylation sites of similar number and position as well as similar distribution of the cysteine residues. The majority of these characteristics are still conserved in the evolutionary most distant member of this family, the Schistosoma mansoni antigen Sm23. Here we introduce this new protein superfamily and characterize the inducible, lymphoid-specific member R2.

Amino Acid Sequence↗
PubMed1995

Genomic structure of SAS, a member of the transmembrane 4 superfamily amplified in human sarcomas.

SAS is a recently identified member of the transmembrane 4 superfamily (TM4SF) that is frequently amplified in human sarcomas. To further its characterization and to confirm its classification, the genomic structure of the SAS gene was determined. The SAS gene covers approximately 3.2 kb of DNA. It contains six exons within its translated region, three of which are highly conserved in the TM4SF. 5' to the translation start site are two putative transcription start sites, two CCAAT consensus sequences, and potential binding sites for both Sp1 and ATF transcription factors. Comparison of SAS organization to human ME491, CD9, and CD53 and murine CD53 and TAPA-1 confirms that SAS is a member of this family of genes and is consistent with the theory that these genes arose through duplication and divergent evolution.

Amino Acid Sequence↗
PubMed1997

Cross-reactivity of monoclonal antibodies to defined human leucocyte differentiation antigens with bovine cells.

Thirty-seven subpanels of monoclonal antibodies (mAbs) included within the Vth International Workshop on Human Leucocyte Differentiation Antigens (Vth Workshop) were assayed for reactivity with bovine peripheral blood leucocytes. Sixty-five of the 772 mAbs (8.4%) stained bovine cells. mAbs from each of the 27 different CD groups that contained a mAb reacting with cattle were further investigated to compare the cellular expression of the antigen in cattle with that reported for the different CD antigens in humans. Two-colour immunofluorescence staining of the Vth Workshop mAbs against characterized bovine leucocyte subpopulation markers that identified monocytes, B cells, CD4, CD8 and WC1 +T cells were used for these analyses. Eighteen of the mAbs to different human CD antigens (CD11a, CD14, CD18, CD21, CD27, CD29, CD49a, CD49b, CD49d, CD49e, CD51, CD61, CD62L, CD62P, CD63, CDw78, CD98, CD100) stained bovine antigens with an almost identical cellular distribution to that reported in humans. This implies that these mAb react with the homologous cattle molecules. Nine mAbs (CD35, CD37, CD49c, CD50, CD54, CD66, CD81, CD88, CD102) stained bovine cells but the cellular distribution of the bovine antigen was different to that reported in humans implying either a different cellular distribution for these antigens in cattle or a reaction with a different molecule. The investigation has allowed the identification of several bovine homologues of human CD antigens that have not been previously defined in cattle and the cross-reacting mAbs will be valuable reagents for future investigations of bovine immunology.

Animals↗
PubMed2000

The L6 membrane proteins--a new four-transmembrane superfamily.

L6, IL-TMP, and TM4SF5 are cell surface proteins predicted to have four transmembrane domains. Previous sequence analysis led to their assignment as members of the tetraspanin superfamily. In this paper, we identify a new sequence (L6D) that is strikingly similar to L6, IL-TMP, and TM4SF5. Analyses of these four sequences indicate that they are not significantly related to genuine tetraspanins, but instead constitute their own L6 superfamily.

Amino Acid Motifs↗
PubMed2005

Intragranular vesiculotubular compartments are involved in piecemeal degranulation by activated human eosinophils.

Eosinophils, leukocytes involved in allergic, inflammatory and immunoregulatory responses, have a distinct capacity to rapidly secrete preformed granule-stored proteins through piecemeal degranulation (PMD), a secretion process based on vesicular transport of proteins from within granules for extracellular release. Eosinophil-specific granules contain cytokines and cationic proteins, such as major basic protein (MBP). We evaluated structural mechanisms responsible for mobilizing proteins from within eosinophil granules. Human eosinophils stimulated for 30-60 min with eotaxin, regulated on activation, normal, T-cell expressed and secreted (RANTES) or platelet activating factor exhibited ultrastructural features of PMD (e.g. losses of granule contents) and extensive vesiculotubular networks within emptying granules. Brefeldin A inhibited granule emptying and collapsed intragranular vesiculotubular networks. By immunonanogold ultrastructural labelings, CD63, a tetraspanin membrane protein, was localized within granules and on vesicles outside of granules, and mobilization of MBP into vesicles within and extending from granules was demonstrated. Electron tomography with three dimension reconstructions revealed granule internal membranes to constitute an elaborate tubular network able to sequester and relocate granule products upon stimulation. We provide new insights into PMD and identify eosinophil specific granules as organelles whose internal tubulovesicular networks are important for the capacity of eosinophils to secrete, by vesicular transport, their content of preformed and granule-stored cytokines and cationic proteins.

Antigens, CD↗
PubMed2004

Increased levels of platelet-derived microparticles in patients with diabetic retinopathy.

Diabetic retinopathy is caused by capillary occlusions. Platelet-derived microparticles (PMPs) stimulate the coagulation cascade and increase leukocyte and endothelial cell adhesions, both of which are key events in the development of diabetic retinopathy. However, the correlation between the levels of PMPs and diabetic retinopathy has not been precisely determined. The PMPs levels and the expression of platelet CD62P and CD63 were measured in 92 diabetic patients. The level of PMPs was significantly correlated with the expression of CD62P (r = 0.76, P < 0.0001) and CD63 (r = 0.71, P < 0.0001). The mean level of PMPs in diabetics (507+/-15/10(4) platelets (plt), mean+/-S.E.) was significantly higher than that in normal. The PMPs levels increased with the progression of the diabetic retinopathy; 480+/-28/10(4) plt in diabetic patients without retinopathy (n = 25), 504+/-40/10(4) plt with mild or moderate non-proliferative diabetic retinopathy (n = 13), 512+/-29/10(4) plt with severe non-proliferative diabetic retinopathy (n = 25), and 528+/-25/10(4) plt with proliferative diabetic retinopathy (n=29). The PMPs level in patients with non-perfused retinal areas (582+/-27/10(4) plt, n = 24) was significantly higher than patients without non-perfused areas (469+/-23/10(4) plt, n = 30; P = 0.0096) and without diabetic retinopathy (P = 0.024). These high correlations indicate that increased levels of PMPs may accelerate diabetic retinopathy.

Adult↗
PubMed1996

Modification of activation-dependent platelet antigens CD62p and CD63 during haemodialysis.

In particular, activated platelets are thought to be involved in the pathophysiology of thrombotic occlusions of vessels. In this study, we evaluated activation-dependent changes in platelet antigens during extracorporeal haemodialysis treatment. Flow cytometry was used in combination with monoclonal antibodies that bind to platelet glycoproteins CD62p (GMP-140) and CD63 (GP53). Maximum peaks of mean channel fluorescence intensity (MCFI) were reached after 60 min in 20/26 procedures in CD62p (P < 0.005) and in 15/25 treatments in CD63 (p < 0.002), respectively. An initial peak of CD62p and CD63 fluorescence expression could be detected in 21/25 and 23/25 treatments, respectively (CD62p within 15, CD63 within 30 min), indicating the early onset of activation. The structural antigen CD41a MCFI slightly decreased over time in all treatments, while CD42b expression did not change. From these results we conclude that haemodialysis contributes to platelet activation and secondary hypercoagulability. Analysis of platelet glycoproteins by flow cytometry may provide clinical information on patients at a higher risk for thrombosis and may help in further improvement of haemodialysis equipment.

Adult↗
PubMed1999

Rapid down-regulation of CD63 transcription by progesterone in human endometrial stromal cells.

Differentiation of endometrial stromal cells (decidualization) plays a crucial role in embryo implantation and maintenance of pregnancy. While progesterone is a key factor in regulating endometrial cell decidualization, the molecular mechanisms remain unclear. In the present study, we investigated the effect of gene transcription in human endometrial stromal cells (ESC) by progesterone, oestrogen or vehicle using the polymerase chain reaction-based differential display methodology. A transcript which is down-regulated by progesterone, but not by vehicle and oestrogen, was identified from a differential display band and the progesterone sensitivity of its expression was verified in Northern blot analysis. The level of the gene expression in progesterone-treated ESC was approximately 60% of that in the vehicle- and oestrogen-treated ESC. This cDNA was revealed to be human CD63 antigen, a recently identified member of the transmembrane 4 superfamily. The inhibitory effect of progesterone is observed within 30 min after hormone treatment. In human endometrium, CD63 mRNA levels were significantly decreased (P < 0.05) during the secretory phase compared with levels during the proliferative phase. This down-regulation of CD63 in vivo elevated levels of progesterone in the secretory phase. These results suggest that CD63 transcription is down-regulated by progesterone in human endometrium.

Adult↗
PubMed1991

CD63/Pltgp40: a platelet activation antigen identical to the stage-specific, melanoma-associated antigen ME491.

CD63 is a 53-Kd lysosomal membrane glycoprotein that has been identified as a platelet activation molecule. The current study presents evidence that CD63 and Pltgp40, a platelet membrane glycoprotein identified in this laboratory, are the same molecule and that CD63/Pltgp40 is identical to the well-characterized, stage-specific melanoma-associated antigen ME491. Identity of CD63 and Pltgp40 was demonstrated by immunoprecipitation and sequential immunodepletion studies, which showed that the anti-Pltgp40 monoclonal antibody (MoAb) H5C6 and an anti-CD63 MoAb CLB/Gran 12 recognized the same 40- to 55-Kd platelet glycoprotein. In addition, the anti-CD63 MoAb specifically recognized immunoaffinity-purified Pltgp40. Amino acid sequences obtained from NH2-terminal and tryptic fragment peptides of Pltgp40 were used to generate complementary DNA (cDNA) probes using the polymerase chain reaction (PCR) technique. A 386-bp cDNA probe partially encoding CD63/Pltgp40 and a full length cDNA probe were 100% identical to the corresponding sequence of ME491. Antibodies H5C6 and CLB/Gran12 immunoprecipitated a 30- to 60-Kd heterodisperse glycoprotein from G361 melanoma cells, as had previously been reported for antibodies recognizing ME491. These data, taken together with the extensive homology recently reported between ME491, the Schistosoma mansoni membrane antigen SM23, CD37, the tumor-associated antigen CO-029, and the target of an antiproliferative antibody-1, suggest that CD63 is a member of a new family of related molecules.

Amino Acid Sequence↗
PubMed2001

Platelet CD40 ligand (CD40L)--subcellular localization, regulation of expression, and inhibition by clopidogrel.

This study compares the subcellular localization and the regulation of expression of the platelet activation markers CD62P and CD63 with CD40 ligand (CD40L) on the surface of washed human platelets. CD40L was expressed upon stimulation with a wide range of platelet activators. However, quantitative flow cytometry demonstrated that, as compared with CD62P and CD63, CD40L expression was low. Upon stimulation with thrombin receptor-activating peptide (TRAP-6), all activation markers were expressed. In contrast, upon stimulation with low concentrations of collagen (1-3 microg/ml), CD40L, but not the granule proteins (CD62P, CD63), were expressed. Using immunofluorescence microscopy, a cytoplasmic staining was observed for CD40L, and cytoplasmic localization of CD40L was verified by Western blotting of subcellular platelet fractions. The staining of CD40L was different from that of filamentous actin and only little association of CD40L with platelet cytoskeleton was found. Surface expression of CD40L was dependent on internal Ca2+ stores and protein kinase C, while the mitogen-activated protein kinases (ERK, p38) or tyrosine kinases were not involved. ADP (30 microM)-induced CD40L expression was not inhibited by aspirin. In contrast, clopidogrel treatment completely abolished ADP-induced expression of CD40L. Finally, the expression level of CD40L was shown to be upregulated by phorbol myristate acetate (PMA) in the promegakaryocytic cell line MEG-01.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed1999

Reduction of platelet activity markers in type II hypercholesterolemic patients by a HMG-CoA-reductase inhibitor.

We have investigated the effects of a potent lipid-lowering therapy on the activity of platelets as measured ex vivo by the surface activation markers CD62 (PADGEM, P-selectin, GMP 140) and CD63 (GP53) in a double-blind, randomized, placebo-controlled study. Treatment with the HMG-CoA-reductase inhibitor fluvastatin (40 mg) significantly reduced the serum low density lipoprotein cholesterol concentration by 30% (p<0.01) and total cholesterol by 25% (p<0.01). The platelet membrane activation markers CD62 (PADGEM, P-selectin, GMP140) and 63 (GP53) significantly decreased by 22 and 13% (in terms of the relative fluorescence intensity) under the treatment with fluvastatin (p<0.05), respectively. The cholesterol-lowering effect is accompanied by a significant reduction of the platelet membrane activation markers CD62 and CD63 reflecting a reduced platelet activity that may contribute to the vasoprotective profile of fluvasatin.

Adult↗
PubMed2005

Flow cytometric analysis of in vitro activated basophils, specific IgE and skin tests in the diagnosis of pollen-associated food allergy.

BACKGROUND: Specific immunoglobulin E (IgE) and commercially available skin prick tests have been demonstrated to be unreliable methods to diagnose pollen-associated food allergy. To evaluate the predictive value of the basophil activation test (BAT) in pollen-associated food allergy, the apple-mediated oral allergy syndrome (OAS) in patients with birch pollinosis was chosen as a representative model. METHODS: Patients with birch pollen allergy and a history of apple-mediated OAS (OAS(+), n = 29), patients with birch allergic without OAS (OAS(-), n = 22), and healthy controls (HC, n = 10) without birch pollen allergy and OAS were included. Apple IgE was quantified by the CAP FEIA method. Skin prick tests were performed with a Jonagold apple extract. Flow cytometric analysis of basophils activated with the same Jonagold extract was based on double staining with anti-IgE/anti-CD63 monoclonal antibodies. RESULTS: Comparison between OAS(+) subjects and HC showed sensitivities and specificities of 96% and 100% for apple IgE and 88% and 100% for the apple skin prick test, respectively. For the BAT, sensitivity and specificity were 100%. In contrast, when nonresponders on the BAT were considered, sensitivity decreased to 90%. In a separate analysis between OAS(+) and OAS(-) subjects, specificities decreased to 30% for apple IgE and to 80% for the apple skin test, respectively. The BAT reached a sensitivity of 88% and a specificity of 75%. CONCLUSION: Flow cytometry-assisted quantification of in vitro basophil activation seems to be a reliable instrument in the diagnosis of this model of pollen-associated food allergy. In addition, this study reemphasizes that the specificity of diagnostic allergy tests decreases considerably when, apart from HC, control individuals with cross-reactive antibodies are included.

Adolescent↗
PubMed2003

Carbon monoxide modulates the response of human basophils to FcepsilonRI stimulation through the heme oxygenase pathway.

We report the effects of exogenous and endogenous carbon monoxide (CO) on the immunological activation of human basophils. Hemin (1-100 microM), a heme oxygenase substrate analogue, significantly increased the formation of bilirubin from partially purified human basophils, thus indicating that these cells express heme oxygenase. This effect was reversed by preincubating the cells for 30 min with Zn-protoporphyrin IX (100 microM), a heme oxygenase inhibitor. Hemin (100 microM) also decreased immunoglobulin G anti-Fcepsilon (anti-IgE)-induced activation of basophils, measured by the expression of a membrane granule-associated protein, identified as cluster differentiation protein 63 (CD63), and by histamine release. These effects were reversed by Zn-protoporphyrin IX (100 microM), by oxyhemoglobin (HbO(2)), a CO scavenger (100 microM), and by 1H-[1,2,4]oxadiazolo[4,3-a] quinoxalin-1-one (ODQ), an inhibitor of the soluble guanylyl cyclase (100 microM). Exposure of basophils to exogenous CO (10 microM for 30 min) also decreased their activation, while nitrogen (N(2)) was ineffective. HbO(2) and ODQ reversed the inhibition, reversing both membrane protein CD63 expression and histamine release to basal values. Both hemin and exogenous CO significantly raised cGMP levels in basophils and blunted the rise of calcium levels caused by immunological activation. This study suggests that CO increases cGMP formation, which in turn induces a fall in intracellular Ca(2+) concentration, thereby resulting in the inhibition of human basophil activation.

Antibodies, Anti-Idiotypic↗
PubMed1999

[Significance of platelet CD62p, CD63 assessment in type 2 diabetes mellitus patients with blood stasis].

OBJECTIVE: To study the relationship between blood stasis and platelet activation and the influential factors on the latter in type 2 diabetes mellitus (DM) patients. METHODS: Platelet CD62p, CD63 expressions were determined in 30 patients of type 2 DM with blood stasis, 27 patients of type 2 DM without blood stasis and 20 normal controls by flow cytometry. RESULTS: CD62p, CD63 levels were significantly higher in type 2 DM with blood stasis group than that without blood stasis group and in normal controls. CD62p was positively correlated with CD63, while positive correlation existed between HbA1c, LDL-C and CD62p in DM patients with blood stasis. CONCLUSION: The increased level of platelet activation was the primary molecular basis in type 2 DM. It was important to perform the Syndrome Differentiation of blood stasis and treatment of activating blood circulation to remove blood stasis in type 2 DM.

Adult↗
PubMed2001

Fusion protein vesicle-associated membrane protein 2 is implicated in IFN-gamma-induced piecemeal degranulation in human eosinophils from atopic individuals.

BACKGROUND: Exocytosis is an integral event during IFN-gamma-induced piecemeal degranulation in eosinophils. In many tissues soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs), including vesicle-associated membrane protein (VAMP), act as specific intracellular receptors to allow granule fusion with the membrane during degranulation. However, the mechanisms underlying eosinophil piecemeal degranulation induced by IFN-gamma are not well understood. OBJECTIVE: We sought to assess whether eosinophils express the vesicular SNARE protein VAMP-2 and to determine the involvement of VAMP-2 in IFN-gamma-induced piecemeal degranulation. METHODS: Human peripheral blood eosinophils (> or =97%) from atopic subjects were subjected to RT-PCR and sequence analysis with specific primers for VAMP-2 mRNA. Western blotting and flow cytometric analysis were carried out to confirm the identity of VAMP-2 and its susceptibility to cleavage by tetanus toxin. Confocal laser scanning microscopy imaging was conducted on double-labeled cytospin preparations of eosinophils at 0, 5, 10, 30, and 60 minutes and 16 hours of IFN-gamma (500 U/mL) stimulation. RESULTS: Eosinophils expressed VAMP-2 mRNA (n = 4 donors), which exhibited 100% homology with human VAMP-2 cDNA on sequencing. Eosinophils were also found to express tetanus toxin-sensitive VAMP-2 protein. RANTES and VAMP-2 immunofluorescence were observed to colocalize to similar intracellular structures by means of confocal imaging. IFN-gamma induced a rapid translocation of VAMP-2(+) organelles toward the cell membrane in correlation with RANTES. CONCLUSIONS: These findings suggest that exocytosis in human eosinophils is regulated by SNAREs, with a specific role indicated for VAMP-2 in piecemeal degranulation.

Amino Acid Sequence↗
PubMed2004

Virulent and avirulent strains of Francisella tularensis prevent acidification and maturation of their phagosomes and escape into the cytoplasm in human macrophages.

Francisella tularensis, the agent of tularemia, is an intracellular pathogen, but little is known about the compartment in which it resides in human macrophages. We have examined the interaction of a recent virulent clinical isolate of F. tularensis subsp. tularensis and the live vaccine strain with human macrophages by immunoelectron and confocal immunofluorescence microscopy. We assessed the maturation of the F. tularensis phagosome by examining its acquisition of the lysosome-associated membrane glycoproteins (LAMPs) CD63 and LAMP1 and the acid hydrolase cathepsin D. Two to four hours after infection, vacuoles containing live F. tularensis cells acquired abundant staining for LAMPs but little or no staining for cathepsin D. However, after 4 h, the colocalization of LAMPs with live F. tularensis organisms declined dramatically. In contrast, vacuoles containing formalin-killed bacteria exhibited intense staining for all of these late endosomal/lysosomal markers at all time points examined (1 to 16 h). We examined the pH of the vacuoles 3 to 4 h after infection by quantitative immunogold staining and by fluorescence staining for lysosomotropic agents. Whereas phagosomes containing killed bacteria stained intensely for these agents, indicating a marked acidification of the phagosomes (pH 5.5), phagosomes containing live F. tularensis did not concentrate these markers and thus were not appreciably acidified (pH 6.7). An ultrastructural analysis of the F. tularensis compartment revealed that during the first 4 h after uptake, the majority of F. tularensis bacteria reside within phagosomes with identifiable membranes. The cytoplasmic side of the membranes of approximately 50% of these phagosomes was coated with densely staining fibrils of approximately 30 nm in length. In many cases, these coated phagosomal membranes appeared to bud, vesiculate, and fragment. By 8 h after infection, the majority of live F. tularensis bacteria lacked any ultrastructurally discernible membrane separating them from the host cell cytoplasm. These results indicate that F. tularensis initially enters a nonacidified phagosome with LAMPs but without cathepsin D and that the phagosomal membrane subsequently becomes morphologically disrupted, allowing the bacteria to gain direct access to the macrophagic cytoplasm. The capacity of F. tularensis to alter the maturation of its phagosome and to enter the cytoplasm is likely an important element of its capacity to parasitize macrophages and has major implications for vaccine development.

Antigens, CD↗
PubMed1991

Biochemical and immunohistochemical characteristics of CD62 and CD63 monoclonal antibodies. Expression of GMP-140 and LIMP-CD63 (CD63 antigen) in human lymphoid tissues.

During platelet secretion granule membrane glycoproteins are translocated to the plasma membrane. We report here the biochemical and immunohistochemical characterization of a panel of platelet-secretion-specific, CD62 and CD63 monoclonal antibodies (MoAb), which we raised to thrombin-activated platelets. The CD62 MoAb identify the alpha-granule membrane protein GMP-140, also designated platelet activation-dependent granule external membrane protein (PADGEM). The number of epitopes on thrombin-activated platelets ranged from 15,000 to 20,000. The CD63 MoAb recognize a 30-60 kDalton integral membrane protein of lysosomes. Due to its distinct localization, we have designated the CD63 antigen lysosome integral membrane protein, CD63 (LIMP-CD63). The number of epitopes on thrombin-activated platelets ranged from 9000 to 11,000. Expression of GMP-140, a member of the Selectin family (also referred as the LEC-CAM family) of adhesion molecules, and LIMP-CD63 was examined on human spleen, thymus and lymph node by immunohistochemistry. Both GMP-140 and LIMP-CD63 showed a wide distribution in lymphoid tissues; vascular endothelial cells and tissue compartments that were readily accessible to blood-borne components were uniformly positive for GMP-140 and LIMP-CD63. Furthermore, LIMP-CD63 was expressed in polymorphonuclear granulocytes and macrophages.

Antibodies, Monoclonal↗