Sequential expression of adhesion and costimulatory molecules in graft-versus-host disease target organs after murine bone marrow transplantation across minor histocompatibility antigen barriers.

Graft-versus-host disease (GVHD) is a potentially fatal complication after allogeneic bone marrow transplantation. However, few data exist thus far on the molecular signals governing leukocyte trafficking during the disease. We therefore investigated the sequential pattern of distinct adhesion, costimulatory, and apoptosis-related molecules in GVHD organs (ileum, colon, skin, and liver) after transplantation across minor histocompatibility barriers (B10.D2 --> BALB/c, both H-2d). To distinguish changes induced by the conditioning regimen from effects achieved by allogeneic cell transfer, syngeneic transplant recipients (BALB/c --> BALB/c) and irradiated nontransplanted mice were added as controls. Irradiation upregulated the expression of vascular cell adhesion molecule (VCAM)-1, intercellular adhesion molecule (ICAM)-l, and B7-2 in ileum, as well as VCAM-1 and B7-2 in colon, on day 3 in all animals. Whereas in syngeneic mice these effects were reversed from day 9 on, allogeneic recipients showed further upregulation of VCAM-1, ICAM-1, B7-1, and B7-2 in these organs on day 22, when GVHD became clinically evident. Infiltration of CD4+ and CD8+ donor T cells was noted on day 9 in skin and liver and on day 22 in ileum and colon. Surprisingly, the expression of several other adhesion molecules, such as ICAM-2, platelet-endothelial cell adhesion molecule 1, E-selectin, and mucosal addressin cell adhesion molecule 1, did not change. Proapoptotic and antiapoptotic markers were balanced in GVHD organs with the exception of spleen, in which a preferential expression of the proapoptotic Bax could be noted. Our results indicate that irradiation-induced upregulation of VCAM-1, ICAM-1, and B7-2 provides early costimulatory signals to incoming donor T cells in the intestine, followed by a cascade of proinflammatory signals in other organs once the alloresponse is established.     

Expression and cell distribution of the intercellular adhesion molecule, vascular cell adhesion molecule, endothelial leukocyte adhesion molecule, and endothelial cell adhesion molecule (CD31) in reactive human lymph nodes and in Hodgkin''s disease.

The immunocytochemical expression of intercellular adhesion molecule (ICAM-1), vascular cell adhesion molecule (VCAM-1), endothelial leukocyte adhesion molecule (ELAM-1), endothelial cell adhesion molecule (EndoCAM CD31), and HLA-DR antigens was investigated in sections of 24 reactive lymph nodes and in 15 cases of Hodgkin's disease. ICAM-1 was detected in sinus macrophages, follicular dendritic reticulum cells (FDRCs), interdigitating reticulum cells (IDRCs), epithelioid macrophages, Hodgkin's cells (HCs), and vascular endothelium. ICAM-1 expression was often associated with that of HLA-DR antigens. VCAM-1 was detected in FDRCs, in fibroblast reticulum cells (FRCs), in macrophages, and in rare blood vessels. EndoCAM (CD31) was constitutively expressed in all types of endothelial cells, sinus macrophages, and in epithelioid granulomas. ELAM-1 was selectively expressed by activated endothelial cells of high endothelium venules (HEVs). When expression of the inducible adhesion molecules ICAM-1, VCAM-1 and ELAM-1 was comparatively evaluated in HEVs, it was found that ICAM-1 + HEVs were present in all reactive and HD nodes, whereas ELAM-1 and/or VCAM-1 were expressed only in those pathologic conditions characterized by high levels of interleukin-1/tumor necrosis factor (IL-1/TNF) production, such as granulomatosis and Hodgkin's disease. In Hodgkin's disease, the expression of ELAM-1/VCAM-1 was more pronounced in cases of nodular sclerosis and was associated with a significantly higher content of perivascular neutrophils.     

Endothelial and smooth muscle cells express leukocyte adhesion molecules heterogeneously during acute rejection of rabbit cardiac allografts.

Interactions of leukocytes with vascular wall cells figure prominently in acute rejection and development of vascular occlusive disease after cardiac transplantation. To investigate the time course and distribution among different types of vessels of expression of endothelial leukocyte adhesion molecules, issues difficult to address in humans, we studied heterotopic transplants of Dutch-Belted rabbit hearts into New Zealand white recipients without immunosuppression (average time to graft failure 8.2 +/- 0.4 days). We found constitutive expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) by coronary arterial endothelium in normal rabbits, whereas myocardial capillaries and the endocardial lining cells showed little or no expression of VCAM-1. VCAM-1 expression increased within 1 day after transplantation on the endothelium of the transplanted aorta and endocardium and on myocardial microvascular endothelial cells. ICAM-1 expression increased remarkably on all endothelia studied from 2 to 8 days after transplantation. Adhesion molecule expression on coronary artery endothelial cells also increased during severe allograft rejection (from a histological score of 1.7 +/- 0.6 pretransplant to 4.8 +/- 0.2 8 days after transplant for VCAM-1 and from 0.9 +/- 0.6 to 4.4 +/- 0.3 for ICAM-1, n = 43 arteries in 5 animals, mean +/- SD). In addition, coronary artery and aortic smooth muscle cells also showed induction of VCAM-1 and ICAM-1 8 days after transplant. We conclude that endothelial activation in a transplanted organ can occur rapidly and varies among microvascular, endocardial, and coronary artery endothelial cells, a point germane to the interpretation of endomyocardial biopsies. Augmented expression of adhesion molecules precedes temporally leukocyte accumulation in vessels. In addition, our finding of activation of coronary artery smooth muscle cells during acute rejection suggests that such episodes may contribute to the development of accelerated coronary arteriosclerosis.     

Comparison of cell adhesion molecule expression in cutaneous leucocytoclastic and lymphocytic vasculitis.

AIMS--To compare the expression of the cell adhesion molecules intercellular adhesion molecule-1 (ICAM-1), ELAM-1 (E-selectin), and vascular cell adhesion molecule-1 (VCAM-1) in cutaneous leucocytoclastic and lymphocytic vasculitis. METHODS--Immunohistochemical analysis was performed on early lesional skin biopsy specimens of leucocytoclastic vasculitis (n = 14), lymphocytic vasculitis (n = 10), non-lesional skin (n = 12), and normal skin (n = 5). A standard immunoperoxidase technique was used to detect expression of ICAM-1, E-selectin, VCAM-1, and the cell markers CD11a, CD11b, CD11c, von Willebrand factor, CD3, CD68, and neutrophil elastase (NP57). RESULTS--Basal keratinocyte intercellular adhesion molecule-1 was expressed in eight (80%) cases of lymphocytic and in only one (7%) case of leucocytoclastic vasculitis, and not in non-lesional skin or control biopsy specimens from normal subjects. E-selectin was expressed on vascular endothelium in eight (57%) cases of leucocytoclastic and in seven (70%) cases of lymphocytic vasculitis. Endothelial vascular cell adhesion molecule-1 expression was seen in three (21%) biopsy specimens of leucocytoclastic and five (50%) of lymphocytic vasculitis. There were increased numbers of cells in the dermal infiltrate stained for NP57, CD11b, and CD11c in leucocytoclastic compared with lymphocytic vasculitis (p < 0.001, p = 0.013, p = 0.009, respectively); immunoreactive positive cells for CD3 and CD11a were increased in lymphocytic compared with leucocytoclastic vasculitis (p < 0.001, p = 0.011, respectively). CONCLUSIONS--These observations indicate that upregulation of adhesion molecule expression occurs in both leucocytoclastic and lymphocytic vasculitis. The different patterns of adhesion molecule expression in the two groups of vasculitis may reflect differences in the local release of cytokines. In particular, detection of intercellular adhesion molecule-1 expression by keratinocytes in lymphocytic vasculitis is consistent with an active role for mediators derived from T lymphocytes in the pathogenesis of the lesion.     

Intercellular adhesion molecule-3 is the predominant co-stimulatory ligand for leukocyte function antigen-1 on human blood dendritic cells

Dendritic cells (DC) are potent stimulators of primary T lymphocyte responses to foreign antigen. The initial DC-T lymphocyte interaction involves the binding of the adhesion molecule leukocyte function antigen-1 (LFA-1; CD11a/CD18) on the T lymphocyte to an intercellular adhesion molecule (ICAM) on the DC. Although blood and tonsil DC express ICAM-1 (CD54) and ICAM-2 (CD102) on their surface, anti-ICAM-1 and anti-ICAM-2 monoclonal antibodies (mAb) have little inhibitory activity on the DC-stimulated mixed leukocyte reaction (MLR). We therefore examined the expression of the more recently identified LFA-1 ligand, ICAM-3 (CD50), in comparison to ICAM-1 and ICAM-2 on blood DC and sought a functional role for ICAM-3 in DC-mediated T lymphocyte responses. Resting blood DC expressed significantly more ICAM-3 than ICAM-1 or ICAM-2 as assessed by flow cytometry. Treatment of resting DC with interferon-γ led to increased expression of ICAM-1; however, ICAM-2 and ICAM-3 levels remained relatively constant. Solid-phase recombinant chimeric molecules ICAM-1-, ICAM-2- and ICAM-3-Fc were able to co-stimulate CD4⁺ T lymphocyte proliferation in conjunction with suboptimal solid-phase CD3 mAb 64.1. However, the anti-ICAM-3 mAb CAL 3.10 inhibited a DC-stimulated MLR to a greater extent than anti-ICAM-1 or anti-ICAM-2 reagents and appeared to act by blocking the DC ICAM-3- T lymphocyte LFA-1 interaction. As ICAM-3 is the predominant LFA-1 ligand on resting blood DC, we postulate that DC may utilize ICAM-3 for initial DC-T lymphocyte interactions, and that ICAM-1, which is up-regulated upon DC activation, and/or ICAM-2, may contribute to DC migration or later phases of the T lymphocyte activation process.     

ICAM-1 and VCAM-1 expression by endothelial cells grown on fibronectin-coated TCPS and PS

Small-diameter vascular grafts rapidly fail as a result of blood coagulation and platelet deposition. Endothelial cells lining the inner side of blood vessels can provide the graft lumen with an antithrombogenic surface. One of the remaining problems is cell detachment after restoration of blood flow, because of infiltration of leukocytes that respond to an inflammatory-like activation of the endothelial cells. This endothelial activation is possibly caused by the surface characteristics of the underlying polymer. To get more insight into the effects of the polymer surface on endothelial cell activation, we seeded human umbilical vein endothelial cells (HUVECs) in various densities and subsequently grew them on tissue culture polystyrene (TCPS; hydrophilic) and polystyrene (PS; hydrophobic) surfaces. To improve cell adhesion, surfaces were coated with purified fibronectin prior to cell seeding. During proliferation, the expressions of the leukocyte adhesion molecules ICAM-1 and VCAM-1 were determined. Results indicate that ICAM-1 expression is not influenced by the character of the polymer surface, and that VCAM-1 expression is slightly higher on the TCPS surface. Expressions of both adhesion molecules are influenced by the seeding density and time of proliferation. At low seeding densities (< or = 10,000 cells/cm(2)), a relatively low percentage of nonexogenously activated cells expressed ICAM-1 during the first 3 days of proliferation compared to higher seeding densities. Although less pronounced, this was also observed for the percentage of cells expressing VCAM-1. During proliferation, the amount of ICAM-1 per endothelial cell increased, whereas the expression of VCAM-1 remained low. The absence of large differences in leukocyte adhesion molecule expression by endothelial cells grown on TCPS or PS is possibly caused by coating of the surfaces with fibronectin. It is known that surface hydrophilicity influences protein adsorption. Although this had no or little effect on leukocyte adhesion molecule expression, endothelial cell growth was affected, because proliferation was slower on the hydrophobic PS.     

Disturbed homeostasis of lung intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 during sepsis

Cecal ligation and puncture (CLP)-induced sepsis in mice was associated with perturbations in vascular adhesion molecules. In CLP mice, lung vascular binding of (125)I-monoclonal antibodies to intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 revealed sharp increases in binding of anti-ICAM-1 and significantly reduced binding of anti-VCAM-1. In whole lung homogenates, intense ICAM-1 up-regulation was found (both in mRNA and in protein levels) during sepsis, whereas very little increase in VCAM-1 could be measured although some increased mRNA was found. During CLP soluble VCAM-1 (sVCAM-1) and soluble ICAM-1 (sICAM-1) appeared in the serum. When mouse dermal microvascular endothelial cells (MDMECs) were incubated with serum from CLP mice, constitutive endothelial VCAM-1 fell in association with the appearance of sVCAM-1 in the supernatant fluids. Under the same conditions, ICAM-1 cell content increased in MDMECs. When MDMECs were evaluated for leukocyte adhesion, exposure to CLP serum caused increased adhesion of neutrophils and decreased adhesion of macrophages and T cells. The progressive build-up in lung myeloperoxidase after CLP was ICAM-1-dependent and independent of VLA-4 and VCAM-1. These data suggest that sepsis disturbs endothelial homeostasis, greatly favoring neutrophil adhesion in the lung microvasculature, thereby putting the lung at increased risk of injury.     

Enhanced expression of intracellular adhesion molecule-1 and P-selectin in the diabetic human retina and choroid.

Elevated expression of intercellular adhesion molecule-1 (ICAM-1) as well as E- and P-selectin occurs on the vascular endothelium in a number of disease states and is thought to play an early critical role in the adhesion of circulating leukocytes to the endothelium. The goal of the present study was to investigate the immunolocalization of these molecules in the retina and choroid of postmortem human tissue sections from nondiabetic and diabetic subjects. Whereas ICAM-1 was localized primarily within the choriocapillaris of nondiabetic subjects, immunoreactivity in diabetics was significantly elevated throughout the choroidal vasculature and within retinal blood vessels (P < 0.05). In the choroid, P-selectin was most prominent in veins of the nondiabetic, whereas in diabetics, P-selectin was significantly elevated in arteries (P < 0.001) and veins (P < 0.05) and, in some cases, was also observed in choriocapillaris. P-selectin immunoreactivity was not observed in the retina of any subject. E-selectin immunoreactivity was not observed in choroid or retina in any subjects. Neutrophil numbers per square millimeter of tissue were significantly elevated in diabetic choroid (P < 0.05) and retina (P < 0.001). Our results demonstrate that ICAM-1 and P-selectin are constitutively expressed in the normal choroid and are upregulated in the choroidal vasculature in diabetes, but only ICAM-1 was upregulated in the retina of diabetic subjects. Increased cell adhesion molecule expression may contribute to the retinal and choroidal microangiopathy observed in diabetics by enhancing leukocyte adhesion and consequently the incidence of capillary obstruction and endothelial cell injury.     

Expression of adhesion molecules relevant to leukocyte migration on the microvilli of liver peritoneal mesothelial cells

To help assess the immunological functions of the liver peritoneum, expression and 3D-microlocalization of adhesion molecules were studied by immuno-SEM and -TEM. The peritoneal tissues of the liver obtained from lipopolysaccharide (LPS, 1.5 microg/g BW for 24 hr)-stimulated (n = 18 including nine controls) and non-stimulated mice (n = 6 including three controls) were analyzed by immunolabeling with 15 nm gold particle single-labeling analysis of ICAM-1, ICAM-2, VCAM-1, MAdCAM-1, PECAM-1, ELAM-1, and CD105 expression. In addition, 10 and 20 nm gold particle double-labeling analysis of ICAM-1 and VCAM-1 was carried out with conventional TEM and BSE (backscatter electron) imaging. Gold particles detected in the peritoneal mesothelial cells were quantified using a computer analyzer, LUZEX III. Only ICAM-1 in non-stimulated mice and both ICAM-1 and VCAM-1 in LPS-stimulated mice were expressed on the mesothelium, but no other adhesion molecules were detected in either condition. Expression of ICAM-1 was consistently about four times greater than that of VCAM-1. Each adhesion molecule was restricted to the microvilli. ICAM-1 was expressed on all microvilli and tended to form clusters of three or four molecules. On the other hand, about 24% of the microvilli expressed VCAM-1 and less clustering was seen. Double-labeling techniques disclosed that VCAM-1 and ICAM-1 were rarely closely associated, usually spaced by about 40 nm. These results suggest that microvilli of the mesothelial cell play a significant role in leukocyte migration in the peritoneal cavity, by providing the important substrates for adhesion, ICAM-1 and VCAM-1.     

Shear stress-mediated changes in the expression of leukocyte adhesion receptors on human umbilical vein endothelial cellsin vitro

Extensive monocyte recruitment is an early phenomenon associated with the development of atherosclerotic lesions, suggesting an active role for the involvement of adhesion receptors expressed by endothelial cells. In this study we describe the contribution of hemodynamic shear forces in regulating the expression of a few of the monocyte adhesion receptors, including intercellular adhesion molecule (ICAM-1), vascular cell adhesion molecule (VCAM-1), and E-selectin on endothelial cells. A parallel plate flow chamber and recirculating flow loop device was used to expose human umbilical vein endothelial cells (HUVECs) to different levels of shear (2–25 dyn/cm²). Subsequently the cells were analyzed either for shear induced changes in the mRNA levels of adhesion receptors by Northern blot analyses or for changes in the surface expression of ICAM-1 using flow cytometry. Results from the fluorescence analysis showed a transient increase in the surface expression of ICAM-1, 12 hr after exposure to 25 dyn/cm² shear, returning to basal levels within 24 hr. This was quite different from the time dependent response of ICAM-1 to lipopolysaccharide (LPS), where ICAM-1 expression was maximally induced 18–24 hr poststimulus. ICAM-1 mRNA level appeared slightly elevated after exposure to shear for 1 hr, compared to basal values, but dropped below basal levels within 6 hr. This biphasic response was seen irrespective of the magnitude of applied shear stress. VCAM-1 mRNA expression, in contrast, decreased below the baseline expression within an hour after onset of flow, and appeared to be considerably down-regulated within 6 hr. After exposure to shear for 24 hr no increase in mRNA levels could be detected for either molecule, at any shear magnitude. E-selectin mRNA was less responsive to shear stress, especially at the lower magnitudes of shear. After an hour of exposure to flow E-selectin mRNA level appeared slightly reduced compared with control levels, but it remained at this level even after 6 hr of flow. These results indicate that the expression of adhesion receptors is sensitive to local shear stresses in a manner that is molecule specific in the short term even though prolonged exposure to flow results in similar down-regulation for both ICAM-1 and VCAM-1.     

Expression of adhesion molecules on cord-blood-derived, cultured human mast cells and effect of dexamethasone on intercellular adhesion molecule-1 expression on the mast cells treated by phorbol myristate acetate

BACKGROUND: Increase in mast-cell number at sites of allergic inflammation has been observed, and glucocorticoids applied to the sites have been shown to result in a significant reduction in mast cells. However, the expression of adhesion molecules on cultured human mast cells and their regulation by glucocorticoids is poorly understood. METHODS: Cultured human mast cells were raised from human umbilical cord-blood cells, and the expression of adhesion molecules on the mast cells was analyzed by flow cytometry. The cells were also incubated with 10 ng/ml phorbol myristate acetate (PMA) for the indicated time, and the effect of dexamethasone on adhesion molecule expression on PMA-treated, cultured human mast cells was examined. RESULTS: Cord-blood-derived, cultured human mast cells constitutively expressed intercellular adhesion molecule-1 (ICAM-1), very late antigen-4 (VLA-4), and macrophage-1 antigen (Mac-1). Weak expression of lymphocyte function-associated antigen-1 (LFA-1) was observed on the cells, whereas they failed to express vascular cell adhesion molecule-1 (VCAM-1). Kinetic studies showed that after a transient downregulation reaching a minimum at 8 h, the expression of ICAM-1 was markedly upregulated on PMA-treated mast cells after a 24-h incubation. In contrast, the expression of VLA-4 and Mac-1 was decreased after the incubation with PMA for 24 h. The PMA-induced upregulation of ICAM-1 was inhibited by dexamethasone in a concentration-dependent manner. CONCLUSION: Our results indicate that cord-blood-derived, cultured human mast cells constitutively express integrins and ICAM-1, but not VCAM-1, and demonstrate for the first time that dexamethasone inhibits the upregulation of ICAM-1 on PMA-treated, cultured human mast cells.     

Adhesion molecules from the LFA-1/ICAM-1, 3 and VLA-4/VCAM-1 pathways on T lymphocytes and vascular endothelium in Graves' and Hashimoto's thyroid glands

Lymphocytic infiltration of the thyroid gland in autoimmune thyroid disorders requires, as a first step, their attachment to endothelial cells (EC) and, subsequently, their interaction with thyrocytes and extracellular matrix proteins. A number of different ligand molecules have been identified to mediate the interaction between EC and leukocyte subpopulations. In this study, we examined by flow cytometry and immunohistochemical techniques, the expression of integrin receptors and their counter-receptors by infiltrating lymphocytes and vascular endothelium in thyroid glands from patients with Graves' disease (GD) and Hashimoto's thyroiditis (HT). A high proportion of GD intrathyroidal T lymphocytes expressed the CD69 and gp95/85 (Ea2) activation antigens as well as an increased number of LFA-α_L, VLA-α1, -α4, -α5, and -β1 integrin receptors, as compared with peripheral blood T lymphocytes from the same patients. The expression of intercellular adhesion molecule (ICAM)-1 was increased in EC from GD and HT thyroids. In addition, an up-regulated de novo expression of vascular cell adhesion molecule (VCAM)-1 was found in EC in GD and HT thyroids, with no reactivity in control thyroids. Dendritic cells in thyroid lymphoid follicles were also positive for ICAM-1 and VCAM-1. In addition, most of intrathyroidal mononuclear cells expressed the ICAM-3 adhesion molecule. This enhanced expression of ICAM-1 and VCAM-1 by thyroid EC in GD and HT may reflect their ability to regulate leukocyte trafficking and activation by means of the expression of specific ligand molecules. Our data suggest that both the LFA-1/ICAM-1, ICAM-3 and VLA-4/VCAM-1 pathways could play a relevant role in localizing and perpetuating the autoimmune response in the thyroid gland in autoimmune thyroid disorders.     

Concentration and Time Effects of Dextran Exposure on Endothelial Cell Viability,Attachment, and Inflammatory Marker Expression <Emphasis Type="Italic">In Vitro</Emphasis>

Dextran is commonly used to alter growth medium rheological properties for in vitro flow experiments in order to match physiological parameters. Despite its acceptance in literature, few studies have examined dextran effects on cells. In this study, we investigated changes in endothelial cell function due to dextran, under static and flow conditions, in a concentration and time-dependent manner. Dextran increased endothelial cell viability, decreased their ability to attach to culture plates and decreased leukocyte adhesion to endothelial cells. Under static conditions, dextran increased protein and mRNA expression of intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) in a concentration and time-dependent manner and caused the nuclear translocation of NF-κB. Steady laminar wall shear stress modulated the effects of dextran on ICAM-1, VCAM-1, and NF-κB expression in straight/tubular in vitro models. When the expression was normalized to their respective time matched static dextran control, it did not affect the ability to detect changes caused by shear on the mRNA expression of ICAM-1 and VCAM-1. This study demonstrates that dextran can alter endothelial cell function and therefore, caution is advised and time matched dextran controls are necessary when using dextran for dynamic cell studies.     

Expression of leukocyte adhesion molecules by endothelial cells seeded on various polymer surfaces

Although endothelial cell seeding in small-diameter vascular prostheses significantly improves graft survival, the detachment of adherent endothelial cells after the restoration of circulation remains one of the major obstacles. Because in vivo experiments indicate that leukocyte infiltration is involved in endothelial cell loss, we hypothesize that seeded endothelial cells become activated and express leukocyte adhesion molecules and cytokines because of an interaction with the underlying polymer surface. The aim of this study was to investigate the expression of the leukocyte adhesion molecules ICAM-1, VCAM-1, PECAM-1, and E-selectin by cultured human umbilical vein endothelial cells (HUVECs) and human adipose microvascular endothelial cells (HAMVECs). The cells were seeded on tissue culture poly(styrene) and the vascular graft materials Dacron and Teflon. The results of this study indicate that the expression of leukocyte adhesion molecules by cultured endothelial cells is mainly affected by the endothelial cell origin, that is, umbilical vein or adipose tissue. Expressions of both ICAM-1 and E-selectin by HUVECs and HAMVECs are characterized by the presence of two cell populations with distinct levels of expression. With respect to endothelial cell seeding in vascular prostheses, the increased expression of E-selectin by microvascular endothelial cells deserves further attention.     

Virulent Treponema pallidum 47 kDa antigen regulates the expression of cell adhesion molecules and binding of T-lymphocytes to cultured human dermal microvascular endothelial cells

Perivasculitis and endothelial cell abnormalities are prominent histopathologic features of syphilis. Various cutaneous lesions are the main clinical features of syphilis. We examined whether Treponema pallidum 47 kDa antigen regulates the expression of cell adhesion molecules on human dermal microvascular endothelial cells (HDMEC) and the regulation of T-lymphocytes binding to HDMEC. Using immunofluorescence flow cytometry and enzyme-linked immunosorbent assay (ELISA), we demonstrated that T. pallidum upregulated the expression of adhesion molecules, including intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1) and E-selectin. The 47 kDa antigen of T. pallidum also activated endothelium as measured by the upregulation of the expression of adhesion molecules on HDMEC, and it also promoted an increased adherence of T-lymphocytes to HDMEC. The expressions of ICAM-1 and VCAM-1 on HDMEC and the adherence of T-lymphocytes to HDMEC were inhibited by treatment with anti-TNF-alpha antibody or anti-IL-1alpha antibody. These results show that T. pallidum or T. pallidum-specific 47 kDa antigen are capable of stimulating HDMEC to increase the expression of ICAM-1, VCAM-1 and E-selectin and thereby, promote the adherence of T-lymphocytes. The whole process may play an important role in the immunopathogenesis of syphilis and it is likely that TNF-alpha and IL-1alpha are involved.     

Elevated expression in situ of selectin and immunoglobulin superfamily type adhesion molecules in retroocular connective tissues from patients with Graves' ophthalmopathy.

Activation of certain adhesion molecules within vascular endothelium and the surrounding extravascular space is a critical event in the recruitment and targeting of an inflammatory response or autoimmune attack to a particular tissue site. We have recently demonstrated that the adhesion of lymphocytes to cultured retroocular fibroblasts obtained from patients with Graves' ophthalmopathy (GO) is mediated predominantly by the interaction of lymphocyte function-associated antigen-1 (LFA-1), expressed on lymphocytes, with intercellular adhesion molecule-1 (ICAM-1), expressed by these cells following exposure to interferon-gamma (IFN-gamma), tumour necrosis factor-alpha (TNF-alpha), IL-1 alpha or purified thyroid-stimulating immunoglobulins. We now report the expression and localization in situ of several adhesion molecules, ICAM-1, endothelial leucocyte adhesion molecule-1 (ELAM-1), vascular cell adhesion molecule-1 (VCAM-1), and LFA-3 in retroocular tissues derived from patients with severe GO (n = 4) and normal individuals (n = 3). Serial cryostat sections of tissue specimens were processed for immunoperoxidase staining using various MoAbs against ICAM-1, ELAM-1, VCAM-1 and LFA-3. In addition, consecutive sections were stained with MoAbs against LFA-1, CD45RO (UCHL-1)DR-human leucocyte antigen (HLA-DR), CD11b/CD18 (Mac-1), and CD11c/CD18 (p150,95). In GO-retroocular tissues, strong immunoreactivity for ICAM-1 and LFA-3 was detected in blood vessels (> 90%), in perimysial fibroblasts surrounding extraocular muscle fibres, and in connective tissue distinct from extraocular muscle. No ICAM-1 or LFA-3 immunoreactivity was present in extraocular muscle cells themselves. ICAM-1 and LFA-3 immunoreactivity in normal tissues was minimal or absent both in connective and muscle tissues. Vascular endothelium was strongly positive for ELAM-1 and VCAM-1 in GO-retroocular tissues, while VCAM-1 immunoreactivity was minimal (< 5% of blood vessels) and ELAM-1 immunoreactivity was generally absent in normal retroocular tissue. LFA-1-expressing, activated mononuclear cells and memory T lymphocytes (CD3+/CD45RO+) were only detected in GO-retrocular tissues, and were mainly localized around blood vessels and in areas of ICAM-1-expressing connective and perimysial tissue. HLA-DR expression was restricted to GO-tissue specimens, with strong immunoreactivity detected in blood vessels, macrophages and connective tissue and perimysial fibroblasts. No HLA-DR was detectable in extraocular muscle cells. In conclusion, infiltration of the orbit in GO by mononuclear cells, and their targeting within the orbit, may depend upon the coordinate expression of certain adhesion and MHC molecules.(ABSTRACT TRUNCATED AT 400 WORDS)     

Expression of ICAM-1, VCAM-1, E-selectin and TNF-alpha on the endothelium of femoral and iliac arteries in thromboangiitis obliterans

Immunohistochemical light and electron microscopical analysis of surgical biopsies obtained from femoral and iliac arteries of patients with thromboangiitis obliterans (TAO) were performed to investigate the presence of tumour necrosis factor-alpha (TNF-alpha) and expression of the endothelial cell adhesion molecules intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin. Expression of ICAM-1, VCAM-1 and E-selectin was increased on endothelium and some inflammatory cells in the thickened intima in all TAO patients. Ultrastructural immunohistochemistry revealed contacts between mononuclear blood cells and ICAM-1-, and E-selectin-positive endothelial cells. These endothelial cells showed morphological signs of activation. The present data indicate that endothelial cells are activated in TAO and that vascular lesions are associated with TNF-alpha secretion by tissue-infiltrating inflammatory cells, ICAM-1-, VCAM-1- and E-selectin expression on endothelial cells and leukocyte adhesion via their ligands. The preferential expression of inducible adhesion molecules in microvessels and mononuclear inflammatory cells suggests that angiogenesis contributes to the persistence of the inflammatory process in TAO.     

Nasal allergen provocation induces adhesion molecule expression and tissue eosinophilia in upper and lower airways

BACKGROUND: Allergic rhinitis (AR) and asthma are characterized by means of a similar inflammatory process in which eosinophils are important effector cells. The migration of eosinophils from the blood into the tissues is dependent on adhesion molecules. OBJECTIVE: To analyze the aspects of nasobronchial cross-talk, we studied the expression of adhesion molecules in nasal and bronchial mucosa after nasal allergen provocation (NP). METHODS: Nine nonasthmatic subjects with seasonal AR and 9 healthy control subjects underwent NP out of season. Bronchial and nasal biopsy specimens were taken before (T(0)) and 24 hours after NP (T(24)). Mucosal sections were analyzed for the presence of eosinophils, IL-5, eotaxin, intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), E-selectin, and human endothelium (CD31). RESULTS: At T(24), an influx of eosinophils was detected in nasal epithelium (P =.01) and lamina propria (P <.01), as well as in bronchial epithelium (P =.05) and lamina propria (P <.05), of the patients with AR. At T(24), increased expression of ICAM-1, as well as increased percentages of ICAM-1+, VCAM-1+, and E-selectin+ vessels, were seen in nasal and bronchial tissue of patients with AR. The number of mucosal eosinophils correlated with the local expression of ICAM-1, E-selectin, and VCAM-1 in patients with AR. CONCLUSION: This study shows that NP in patients with AR results in generalized airway inflammation through upregulation of adhesion molecules.