Selective enhancement of endothelial cell VCAM-1 expression by interleukin-10 in the presence of activated leucocytes

Biomarkers for Premature Coronary Artery Disease (PCAD): A Case Control Study

Coronary artery disease (CAD) is often associated with the older generation. However, in recent years, there is an increasing trend in the prevalence of CAD among the younger population; this is known as premature CAD. Although biomarkers for CAD have been established, there are limited studies focusing on premature CAD especially among the Malay male population. Thus, the aim of this research was to compare the biomarkers between premature CAD (PCAD) and older CAD (OCAD) among Malay males. Subjects, recruited from the Universiti Kebangsaan Malaysia Medical Centre and National Heart Institution, were divided into four groups: healthy control < 45 years old; premature CAD (PCAD) < 45 years old; healthy control > 60 years old; and older CAD (OCAD) > 60 years old, with n = 30 for each group. Ten potential markers for CAD including soluble sVCAM-1, sICAM-1, interleukin-2, interleukin-6, interleukin-10, Apo-E and Apo-A1, homocysteine, CRP, and vitamin D levels were examined. Our results revealed premature CAD patients had significantly higher values (p < 0.05) of sVCAM-1, CRP, interleukin-6, and vitamin D when compared to the age-matched controls. Similarly, older CAD patients showed higher levels of sVCAM-1, CRP, and interleukin-2 when compared to their age-matched controls. After adjusting for multiple parameters, only CRP remained significant for PCAD and interleukin-2 remained significant for CAD. This indicates that premature CAD and older CAD patients showed different profiles of protein biomarkers. CRP has the potential to become a biomarker for premature CAD while interleukin-2 is a better biomarker for older CAD together with other typical panels of protein biomarkers.

Expression of adhesion molecules, chemokines and matrix metallo- proteinases (MMPs) in viable and degenerating stage of Taenia solium metacestode in swine neurocysticercosis

Neurocysticercosis (NCC) is a parasitic infection of central nervous system (CNS). Expression of adhesion molecules, chemokines and matrix metalloproteinases (MMPs) were investigated on brain tissues surrounding viable (n=15) and degenerating cysticerci (n=15) of Taenia solium in swine by real-time RT-PCR and ELISA. Gelatin gel zymography was performed for MMPs activity. ICAM-1 (intercellular adhesion molecule-1), E-selectin, MIP-1α (macrophage inflammatory protein-1α), Eotaxin-1 and RANTES (regulated on activation, normal T cell expressed and secreted) were associated with degenerating cysticerci (cysts). However, VCAM-1 (vascular cell adhesion molecule-1), MCP-1 (monocyte chemotactic protein-1), MMP-2 and MMP-9 were associated with both viable and degenerating cysts. In conclusion, viable and degenerating cysticerci have different immune molecule profiles and role of these molecules in disease pathogenesis needs to be investigated.

Does Inflammation Have a Role in the Pathogenesis of Cardiac Syndrome X? A Genetic-Based Clinical Study With Assessment of Multiple Cytokine Levels

We compared Turkish patients with cardiac syndrome X (CSX) and controls with respect to serum pro- and anti-inflammatory cytokine levels, as well as the single-nucleotide polymorphisms located in the promoter regions of their related genes. This study included 111 consecutive patients angiographically diagnosed with CSX and 111 healthy controls with similar demographic characteristics. Serum interleukin (IL) 6, tumor necrosis factor α (TNF-α), and IL-10 levels were measured, and the genotypes of the patients and controls were determined using standard methods. Serum IL-6 and IL-10 levels were significantly higher in the CSX group than in the control group ( P < .01, respectively). Serum TNF-α level was lower in the CSX group than in the control group ( P < .001). On the other hand, participants with CSX and healthy controls were not significantly different with respect to the genotype distributions of IL-6, TNF-α, and IL-10 genes. As a result of our study, both pro-inflammatory and anti-inflammatory cytokines may play a role in the pathogenesis of CSX. In contrast, the studied gene polymorphisms did not influence CSX pathogenesis.

Adhesion between human neutrophils and immobilized endothelial ligand vascular cell adhesion molecule 1: divalent ion effects

Integrin-mediated adhesion of circulating neutrophils to endothelium during inflammation involves multiple adhesion molecules on both neutrophils and endothelium. Most studies of neutrophil adhesion have focused on adhesion to ICAM-1 (mediated by beta(2) integrins), but interaction with the endothelial ligand vascular cell adhesion molecule 1 (VCAM-1) may also play a role in neutrophil adhesion to activated endothelium. In this study we demonstrate significant adhesion between neutrophils and VCAM-1 mediated by beta(1) integrins, principally via alpha(4)beta(1) (VLA-4). We characterize the dynamics of adhesion in terms of rate constants for a two-step bond formation process, the first involving juxtaposition of active molecules with substrate and the second involving bond formation. The results indicate that the first step is rate limiting for VLA-4-VCAM-1 interactions. Changing divalent cation composition affects these coefficients, implicating molecular conformational changes as a key step in the process.

IL-10 promotes resistance to apoptosis and metastatic potential in lung tumor cell lines

Treatment of non-small cell lung carcinoma (NSCLC) remains at a disappointingly low success rate. Not only is metastatic spread common in NSCLC, but therapeutic success decreases dramatically once metastases are present. Understanding factors which contribute to poor prognosis in NSCLC is critical for development of more successful therapeutic approaches. Interleukin-10 (IL-10) expression has been shown in several studies to correlate with a poorer prognosis in NSCLC; however, the mechanisms by which IL-10 affects lung tumor growth and metastases are unclear. The goal of this study was to evaluate the effects of tumor-derived IL-10 on the growth and metastasis of lung cancer cells in a murine model. Lewis lung carcinoma cells were stably transfected with the chicken ovalbumin gene (cOVA) as a model tumor antigen (LL43 tumor cells) and subsequently transfected with the murine IL-10 gene (LL43-10 tumor cells). Subcutaneous growth of the LL43 tumor cells was not affected by expression of IL-10. However, LL43-10 tumors had a fourfold increase in tumor microvessel density, as indicated by CD31 staining. Metastatic potential was also increased in IL-10-expressing lung tumor cells, leading to a greater number of tumor cells in lymph nodes draining the primary tumor site. Finally, exposure of Lewis lung tumor cells in vitro to exogenous IL-10 dramatically increased their resistance to UV-induced apoptosis. These results indicate that a primary effect of IL-10 on lung cancer cells may be to increase their metastatic potential by promoting angiogenesis and resistance to apoptosis.

Interleukin-10 and the immune response against cancer: a counterpoint

Although interleukin-10 (IL-10) is commonly regarded as an anti-inflammatory, immunosuppressive cytokine that favors tumor escape from immune surveillance, a wealth of evidence is accumulating that IL-10 also possesses some immunostimulating properties. In fact, IL-10 has the pleiotropic ability of influencing positively and negatively the function of innate and adaptive immunity in different experimental models, which makes it questionable to merely categorize this cytokine as a target of anti-immune escape therapeutic strategies or rather, as an immunological adjuvant in the fight against cancer. Here, we review available data about the immunostimulating anticancer properties of IL-10, and in particular, we focus on the hypothesis that in contrast to what occurs in secondary lymphoid organs, IL-10 overexpression within the tumor microenvironment may catalyze cancer immune rejection.

Increased E-selectin, IL-8 and IL-10 gene expression in human skin after minimal trauma

While clinical observations suggest that trauma to the skin plays a critical role in the induction of skin lesions in some skin diseases, the mechanism by which these lesions are induced is not known. We have postulated that minor trauma to the skin may lead to the expression of critical adhesion molecules on epidermal endothelial cells (E-selectin) and pro-inflammatory cytokines, which would predispose these areas to the development of skin lesions. In order to test this hypothesis normal inner arm skin of 11 normal subjects was gently rubbed with a pencil eraser for 2 min. Four hours after rubbing, skin biopsies were obtained from the rubbed site and from adjacent normal, unrubbed inner arm skin. Expression of E-selectin, intercellular adhesion molecules (ICAM-1) and the mRNA of selected cytokines was studied utilizing real time polymerase chain reactions. Biopsies were also examined for the presence of an inflammatory infiltrate and for the presence of E-selectin and ICAM-1. No clinical or histologic changes were seen in the skin expression/unrubbed skin expression = 9.0; (median ratio rubbed skin expression/unrubbed skin expression range 0.9-161.0), ICAM-1 (median rubbed skin expression/unrubbed skin expression = 3.2; range 0.9-19.8), IL-8 (median rubbed skin expression/unrubbed skin expression = 6.6; range 2.6-57.3) and IL-10 (median rubbed skin expression/unrubbed skin expression = 13.1; range 2.4-29.0) was noted. Immunohistochemistry revealed the presence of E-selectin in the dermal blood vessels in three of four subjects 4 h after rubbing but not in the unrubbed skin. Changes in ICAM -1 or HLA-DR deposits were seen in the rubbed compared with the unrubbed skin. These findings demonstrated that minor trauma to skin may induce expression of E-selectin, ICAM-1 and IL-8, which may make the skin a more permissive site for the development of inflammatory reactions. These findings may play an important role in the development of skin lesions in areas of minor trauma.

Nitric oxide expression by interleukin-10 in the endoscopic and open methods of vein harvesting in coronary artery bypass surgery

OBJECTIVE

Interleukin-10 (IL-10) is an anti-inflammatory cytokine that suppresses lymphocyte functions, regulates production of proinflammatory cytokines, and suppresses nitric oxide production by activated macrophages. We examined IL-10 expression and its value as a surrogate index for nitric oxide (NO) production in endothelial cultures obtained from saphenous vein samples.

METHODS

Using 2 different techniques (the open and endoscopic), we harvested samples of human saphenous veins from 90 randomly selected patients undergoing coronary artery bypass surgery (CABG). Endothelial cells collected from the vein samples retrieved through both techniques were cultured for 72 hours. Using a solid phase enzyme linked-immuno-sorbent assay (ELISA), we analyzed pre- and postoperative sera, in addition to the supernatants from the cultures, for IL-10.

RESULTS

Mean preoperative levels of IL-10 (0.09 +/- 0.04 pg/mL) did not differ significantly from that for postoperative sera (0.14 +/- 0.17 pg/mL) (P = 0.54). Mean IL-10 levels for endothelial cell culture supernatants did not differ significantly between the endoscopic (0.32 +/- 0.39 pg/mL) and the open method (0.46 +/- 0.80 pg/mL) (P= 0.30).

CONCLUSION

Our findings indicate that endoscopic and open saphenectomies are technically comparable with respect to their effects on IL-10 release during saphenous vein harvesting for CABG. We recommend the endoscopic method for its low morbidity and earlier hospital discharge.

Interleukin-10 and the interleukin-10 receptor

Interleukin-10 (IL-10), first recognized for its ability to inhibit activation and effector function of T cells, monocytes, and macrophages, is a multifunctional cytokine with diverse effects on most hemopoietic cell types. The principal routine function of IL-10 appears to be to limit and ultimately terminate inflammatory responses. In addition to these activities, IL-10 regulates growth and/or differentiation of B cells, NK cells, cytotoxic and helper T cells, mast cells, granulocytes, dendritic cells, keratinocytes, and endothelial cells. IL-10 plays a key role in differentiation and function of a newly appreciated type of T cell, the T regulatory cell, which may figure prominently in control of immune responses and tolerance in vivo. Uniquely among hemopoietic cytokines, IL-10 has closely related homologs in several virus genomes, which testify to its crucial role in regulating immune and inflammatory responses. This review highlights findings that have advanced our understanding of IL-10 and its receptor, as well as its in vivo function in health and disease.

Glucocorticoids and IL-10, but not 6-MP, 5-ASA or sulfasalazine block endothelial expression of MAdCAM-1: implications for inflammatory bowel disease therapy

BACKGROUND

Enhanced MAdCAM-1 (mucosal addressin cell adhesion molecule-1) expression is associated with the aetiology of inflammatory bowel disease, but little is known about MAdCAM-1: regulation, or how inflammatory bowel disease therapies modulate MAdCAM-1.

AIM

To examine how agents currently used to treat inflammatory bowel disease affect MAdCAM-1: induced by tnf-alpha in an in vitro model of inflammatory bowel disease.

METHODS

Endothelial monolayers were pretreated with dexamethasone (DEX): 5-aminosalicylic acid (5-ASA), 6-mercaptopurine (6-MP), sulfasalazine or interleukin-10: (IL-10: prior to TNF-alpha (20 ng/mL), and MAdCAM-1: measured by Western blotting, RT-PCR, EMSA and lymphocyte adhesion assays.

RESULTS

MAdCAM-1: was induced dose- and time-dependently by TNF-alpha on endothelial cells. Either dexamethasone or IL-10: reduced TNF-alpha-induced MAdCAM-1: protein, mRNA and lymphocyte adhesion. However, neither 5-ASA, sulfasalazine nor 6-MP blocked MAdCAM-1 induction.

CONCLUSIONS

Our data indicate that dexamethasone or IL-10 can exert therapeutic activity in inflammatory bowel disease through MAdCAM-1 inhibition. 5-ASA, sulfasalazine and 6-MP, while beneficial in inflammatory bowel disease, do not directly control MAdCAM-1, and are beneficial through inhibition of other inflammatory processes.

Interleukin-10 and the Interleukin-10 Receptor

Interleukin-10 (IL-10), first recognized for its ability to inhibit activation and effector function of T cells, monocytes, and macrophages, is a multifunctional cytokine with diverse effects on most hemopoietic cell types. The principal routine function of IL-10 appears to be to limit and ultimately terminate inflammatory responses. In addition to these activities, IL-10 regulates growth and/or differentiation of B cells, NK cells, cytotoxic and helper T cells, mast cells, granulocytes, dendritic cells, keratinocytes, and endothelial cells. IL-10 plays a key role in differentiation and function of a newly appreciated type of T cell, the T regulatory cell, which may figure prominently in control of immune responses and tolerance in vivo. Uniquely among hemopoietic cytokines, IL-10 has closely related homologs in several virus genomes, which testify to its crucial role in regulating immune and inflammatory responses. This review highlights findings that have advanced our understanding of IL-10 and its receptor, as well as its in vivo function in health and disease.

Different therapeutic outcomes in experimental allergic encephalomyelitis dependent upon the mode of delivery of IL-10: a comparison of the effects of protein, adenoviral or retroviral IL-10 delivery into the central nervous system

Experimental allergic encephalomyelitis (EAE) is a CNS autoimmune disease mediated by the action of CD4(+) T cells, macrophages, and proinflammatory cytokines. IL-10 is a cytokine shown to have many anti-inflammatory properties. Studies have shown both inhibition and exacerbation of EAE after systemic IL-10 protein administration. We have compared the inhibitory effect in EAE of Il10 gene delivery in the CNS. Fibroblasts transduced with retroviral vectors expressing IL-10 could inhibit EAE. This was not associated with a prevention of cellular recruitment but an alteration in their phenotype, notably an increase in the numbers of CD8(+) T and B cells. In marked contrast, CNS delivery of adenovirus coding for mouse IL-10 or IL-10 protein performed over a wide dose range failed to inhibit disease, despite producing similar or greater amounts of IL-10 protein. Thus the action of IL-10 may differ depending on the local cytokine microenvironment produced by the gene-secreting cell types.

Interleukin 10 regulates cellular responses in monocyte/endothelial cell co-cultures

Adhesive interactions between monocytes and vascular endothelial cells increase the expression of the inflammatory genes, tissue factor (TF) and E-selectin, thus contributing to the inflammatory process. In this study, we have shown that these responses could be regulated by the immunomodulatory cytokine interleukin 10 (IL-10). IL-10 reduced TF generation in monocyte/endothelium co-cultures (64. 3 +/- 3.3% reduction, P < 0.01, n = 4) by acting directly on monocytes, whereas IL-4 inhibited TF expression in both monocytes and endothelium. Similarly, IL-10 reduced the induction of endothelial E-selectin by monocytes (100% reduction at 21 h), but had no effect on cytokine-induced E-selectin expression. IL-10 itself was not able to induce E-selectin protein or mRNA in endothelial cells. IL-10 mRNA was detected in monocytes after 6 h co-culture with endothelial cells, and was sustained for up to 30 h. Finally, IL-10 significantly reduced the adhesion of monocytes to endothelium (45% reduction), which may account in part for the inhibitory actions of IL-10. We conclude that IL-10 has an anti-inflammatory effect on monocyte/endothelium interactions, and may itself be produced as a result of such interactions.

Interleukin-10 inhibits macrophage-induced glomerular injury

The ability of interleukin-10 (IL-10) to inhibit macrophage recruitment, activation, and proliferation in vivo was studied in a macrophage-mediated, but T cell-independent, passive anti-glomerular basement membrane antibody-induced model of glomerulonephritis (GN) in rats. Treatment with recombinant murine IL-10 resulted in dose-dependent reductions in proteinuria (high dose: 16 +/- 1 mg/24 h; low dose: 30 +/- 2 mg/24 h; control treatment: 69 +/- 6 mg/24 h; normal: 7 +/- 1 mg/24 h) and glomerular macrophage recruitment (high dose: 1.8 +/- 0.1 macrophages per glomerular cross section [c/gcs]; low dose: 5.5 +/- 0.2 c/gcs; control treatment: 12.1 +/- 0.6 c/gcs). Macrophage and intrinsic glomerular cell proliferation were reduced at both doses of IL-10, as was glomerular expression of P-selectin and monocyte chemoattractant protein-1. IL-10 treatment also resulted in a dose-dependent reduction of macrophage activation as indicated by MHC class II and IL-1beta expression. Glomerular nitrite production by isolated cultured glomeruli was reduced after IL-10 treatment in vivo (high dose: 2.3 +/- 2.3 nmol/10(4) glomeruli per 72 h; low dose: 28 +/- 5 nmol/10(4) glomeruli per 72 h; control treatment: 82 +/- 11 nmol/10(4) glomeruli per 72 h). Tumor necrosis factor-alpha production was abolished by high-dose treatment and reduced by the lower dose (3.8 +/- 3.8 pg/10(4) glomeruli per 72 h; control treatment: 249 +/- 23 pg/10(4) glomeruli per 72 h). These studies demonstrate that IL-10 directly attenuates glomerular macrophage recruitment, activation, and proliferation in vivo and can significantly attenuate macrophage-mediated GN independent of any effects on T cells.

Systemic viral interleukin-10 gene delivery prevents cartilage invasion by human rheumatoid synovial tissue engrafted in SCID mice

OBJECTIVE

To assess the effects of viral interleukin-10 (vIL-10) gene delivery on human rheumatoid synovial tissue.

METHODS

SCID mice were engrafted subcutaneously with human rheumatoid synovial tissue and homologous cartilage before systemic injection of 10(9) plaque-forming units of type 5 E1a Elb-deficient non-replicative adenovirus vector containing the vIL-10 gene under control of the cytomegalovirus promoter (AdvIL-10; n = 10) or a control gene (AdvIL-10mut; n = 7). Three weeks later, the graft was removed for histologic analysis of cartilage invasion by synovial tissue. The number of CD3-positive mononuclear cells was assessed in the synovial tissue by immunohistology. Messenger RNA (mRNA) expression of matrix metalloproteinase 3 (MMP-3), tissue inhibitor of metalloproteinases 1 (TIMP-1), and proinflammatory cytokines was determined by polymerase chain reaction.

RESULTS

Systemic vIL-10 gene transfer resulted in high sustained production of vIL-10 protein in SCID mouse sera (mean +/- SD 25 +/- 5 ng/ml on day 40 post vector injection). Moreover, vIL-10 mRNA expression was detected in the synovial tissue 3 weeks after intravenous injection of AdvIL-10, reflecting the gene transfer in the human graft. In animals treated with AdvIL-10, cartilage invasion by rheumatoid synovial tissue was significantly inhibited compared with the control vector (mean +/- SD histologic score 2.5 +/- 0.52 versus 0.75 +/-0.8; P < 0.0001). The number of T cells infiltrating the synovium and perichondral resorption in the animals treated with AdvIL-10 gene were not significantly modified relative to the control vector. In animals treated with AdvIL-10, the MMP-3-TIMP-1 balance was partially restored, independent of the effect on mRNA expression of tumor necrosis factor a, IL-1, IL-6, or IL-8.

CONCLUSION

Systemic vIL-10 gene transfer prevented cartilage invasion by synovial tissue engrafted in SCID mice. This model offers the opportunity to study the biologic effects of gene transfer in vivo in rheumatoid synovium.

IL-10 Regulates Thrombus-Induced Vein Wall Inflammation and Thrombosis

Vein wall inflammation associated with venous thrombosis is mediated by an imbalance in proinflammatory as compared with antiinflammatory molecules. We hypothesize that IL-10 is an important antiinflammatory cytokine that influences vein wall inflammation and thrombus propagation during venous thrombosis. To test this hypothesis a model of inferior vena caval thrombosis was used. Studies were performed at sacrifice 2 days after thrombus induction and included leukocyte morphometrics, myeloperoxidase activity, vein wall permeability, thrombus weight, and IL-10 ELISA analysis from the vein wall. IL-10 was elevated in the vein wall during venous thrombosis. Neutralization of IL-10 increased inflammation, while supplementation with rIL-10 demonstrated a dose- and time-dependent decrease in inflammation. Interestingly, a low 2.5-μg rIL-10 dose given at time of initiation of thrombosis most significantly decreased inflammation. Thrombus weight was importantly diminished by reconstitution of IL-10. These studies support an important role for IL-10 in the regulation of thrombus-associated inflammation and thrombosis and suggest that IL-10 could be used as a therapeutic agent in the treatment of venous thrombosis.

Interleukin-4 and interleukin-10 are chondroprotective and decrease mononuclear cell recruitment in human rheumatoid synovium in vivo

We used the severe combined immunodeficient (SCID) mouse model to assess the effect of interleukin-4 (IL-4) or IL-10 injection on cartilage degradation and mononuclear cell (MNC) recruitment to human rheumatoid synovium in vivo. Human rheumatoid synovium and cartilage from five rheumatoid arthritis patients, obtained after joint replacement surgery, were engrafted subcutaneously to 6-8-week-old SCID CB17 mice. Synovial tissues were injected with recombinant human IL-4 (rhIL-4, 100 ng; rhIL-10, 100 ng), both cytokines, or tumour necrosis factor-alpha (TNF-alpha) (1000 U), or phosphate-buffered saline twice a week for 4 weeks. The graft was removed and immunochemical analysis was carried out to assess intracellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin expression. Moreover, cartilage degradation was assessed through the quantification of the erosion surface on a computerized image of the engrafted cartilage at high power view. MNC recruitment in the synovial tissue was determined by labelling blood MNC with indium-111 before their intraperitoneal injection. The activity obtained in the region of the graft were determined with a gamma camera 72 hr postinjection. The results are expressed as a percentage of initial injected activity. After 4 weeks we observed a decrease of cartilage area in controls (77 +/- 8%), inhibited after injection of IL-4, IL-10, or both cytokines (90 +/- 3%, 89.1 +/- 4%, 89.2 +/- 5% respectively), and 57 +/- 17% after TNF-alpha injection. The % MNC activity in the graft decreased to 77 +/- 81% (NS), 9 +/- 4% (P < 0.003) and 19 +/- 6% (P < 0.007) compared with untreated synovial tissue after treatment with IL-4, IL-10, or both cytokines, respectively. Moreover, IL-10 but not IL-4 decreased the expression of ICAM-1 but not VCAM-1 or E-selectin by synovial cells. These results suggest that IL-10 and IL-4 could have chondroprotective properties, and that IL-10 but not IL-4 inhibits MNC traffic towards the synovial tissue efficiently.