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We analyzed migration of monocytes under the effect of apocinin (NADPH inhibitor) and PD98059 (blocker of extracellular MEK/ERK kinase involved in Nox4 oxidase-mediated migration of monocytes). Migration of monocytes stimulated by cysteine-containing peptides (fragments of chemokines with free thiol group MCP-1 and fractalkine) was completely inhibited by apocinin and MEK/ERK blocker. It is assumed that the stimulating effect of cysteine-containing peptides on monocyte migration is mediated by the NADPH-oxidase system, in particular, Nox4.

Monocyte chemotactic protein-1 (MCP-1) is a chemokine that stimulates monocytes and macrophage migration into the sites of acute of chronic inflammation. Our study shows morphological changes in ischemic myocardium followed by the administration of two synthetic structural fragments of MCP-1 that are monocyte/macrophage migration inductor peptide IX and peptide X an inhibitor. Results show that peptides can change time points of the inflammatory response in myocardium. Peptide IX administration leads to increased and accelerated inflammatory response, i. e. attracts an additional number of monocytes and macrophages into the inflammatory focus. The introduction of the peptide X observed prolonged inflammatory process with the overall gain signs of myocardial damage.

Automated Fmoc solid-phase technique was used to synthesize Cys-containing linear peptide fragments of monocyte chemoattractant protein-1 and chemokine domain of fractalkine along with their analogues with Cys residue being either modified or replaced with Ser. Chimeric symmetric and asymmetric disulfides were also prepared from the former linear precursors. A SAR study on a set of the newly synthesized peptides revealed that capacity to stimulate migration of monocytes and to influence cell motility in vitro, in general, critically depends on the presence of Cys free thiol group in the molecule. Notably, all analogs lacking this feature, including chimeric disulfides, demonstrated lack of effect on monocyte migration.

Aim: To investigate a balance between circulating regulatory T lymphocytes (Treg) exerting antiatherogenic activity and T helper type 1 (Th1) and T helper type 17 (Th1 7) cells having proatherogenic activity in patients with stable coronary artery disease (CAD) and different degrees of coronary atherosclerosis., Subjects and Methods: According to coronary angiography findings, 80 patients were allocated to 4 groups: 1) 18 patients with intact coronary arteries; 2) 21 with no progressive coronary atherosclerosis; 3) 16 with progressive coronary atherosclerosis (more than 50% stenosis) in the native coronary arteries; 4) 25 patients with three-vessel lesions. Groups 2 and 3 patients had undergone coronary stenting 23.8 ± 8.4 and 22.4 ± 8.7 months before their enrollment, respectively. Lymphocytes were typed by direct immunocytofluorometry: Treg was defined as CD4+CD25highCD127low and CD4+FoxP3+ lymphocytes. For CD4+IL-17a+ Th17 and CD4+INFgamma Th1 analysis, mononuclear cells were preactivated by culture. The serum levels of high-sensitivity C-reactive protein, IL-10, sCD25, and IL-17a were determined by nephelometry, chemiluminescence (Immulite) and ELISA, respectively., Results: Group 4 was found to have lower Treg levels and higher Th17 levels than Group 1. The ratio of Th17/Treg proved to be higher in Groups 3 and 4 than in Group 1 and that of (Th1+Th17)/Treg was higher in Group 3 than in Group 2. The female patients had higher Tregs levels than the male ones. The Th17/Treg index turned out to be increased in patients with a history of myocardial infarction., Conclusion: The imbalance of pro- and anti-atherogenic lymphocyte subpopulations plays a role in the pathogenesis of CAD and is associated with progressive atherosclerosis.

Leukocyte chemotaxis to the area of tissue damage is mediated by chemokines. According to the primary structure, chemokines are divided into four families, fractalkine (CX3CL1) is the only one member of CX3C family and the only membrane-bound chemokine. Fractalkine molecule includes the extracellular N-terminal chemokine domain, mucin-like rod, the transmembrane and the intracellular domains. In membrane-bound state fractalkine has the properties of an adhesion molecule. Chemokine domain of fractalkine (CDF) is released from cell membrane by proteolysis, and this soluble form acts as a chemoattractant for leukocytes expressing fractalkine receptor CX3CR1. Fractalkine is involved in development of a number of pathological processes caused by inflammation, and therefore a search for fractalkine inhibitors is very important. For this purpose we identified several antigenic determinants--the fragments of CDF, and the following peptides were synthesized--P41-52 H-Leu-Glu-Thr-Arg-Gln-His-Arg-Leu-Phe-Cys-Ala-Asp-NH2, P53-60 H-Pro-Lys-Glu-Gln-Trp-Val-Lys-Asp-NH2 and P60-71 H-Asp-Ala-Met-Gln-His-Leu-Asp-Arg-Gln-Ala-Ala-Ala-NH2. The peptide effects on adhesion and migration of human peripheral blood monocytes expressing fractalkine receptors were investigated. In the presence of CDF and P41-52 we observed the increased adhesion and migration of monocytes compared with spontaneous values. Peptides P53-60 and P60-71 significantly inhibited monocyte adhesion and migration stimulated by CDF. Since the chemotactic activity of chemokines was shown to be dependent on their binding to glycosaminoglycans of the cell surface and extracellular matrix, the effect ofpeptides on the interaction of CDF with heparin was analyzed by ELISA. Peptide P41-52 competed with CDF for heparin binding, while peptides P53-60 and P60-71 had no significant activity.

Objective and Design: The peptide from C-terminal domain of MCP-1 (Ingramon) has been shown to inhibit monocyte migration and possess anti-inflammatory activity in animal models of inflammation and post-angioplasty restenosis. Here, we investigate the effect of Ingramon treatment on blood levels of acute-phase reactants and chemokines in patients after coronary stenting and the mechanisms of Ingramon anti-inflammatory activity., Subjects: Eighty-seven patients with ischemic heart disease (IHD) who faced the necessity of coronary angiography (CA) were enrolled. In 67 patients, one-stage coronary stenting was performed; 33 of them were treated with Ingramon in addition to standard therapy. Twenty patients underwent CA only., Methods: High-sensitivity C-reactive protein (hsCRP) and fibrinogen blood levels were detected routinely. The chemokine concentration in plasma was measured by enzyme-linked immunosorbent assay (ELISA) or cytometric bead array-based immunoassay. Intracellular Ca(2+) levels and cell surface integrin exposure were assayed by flow cytometry. MCP-1 dimerization was studied by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). MCP-1-heparin binding was assessed with a biosensor and ELISA., Results and Conclusions: Ingramon treatment was accompanied by less pronounced elevation of hsCRP and fibrinogen levels and decreased MCP-1 concentration in plasma in patients after coronary stenting. Ingramon had no effect on MCP-1 interaction with cell receptors or MCP-1 dimerization, but inhibited MCP-1 binding to heparin. The anti-inflammatory activity of the peptide may be mediated by an impaired chemokine interaction with glycosaminoglycans.

Rapamycin contributes to the expansion of regulatory T cells (Tregs) in vitro. We investigated CD4(+)CD25(high)CD127(low) Treg level dynamics as well as the major parameters of cell immunity and sCD25 and highly sensitive C-reactive protein (hsCRP) concentrations in the blood of patients after coronary stenting (CS) with sirolimus (rapamycin)-eluting stents (SES; n = 43). The relation between initial Treg values and the severity of coronary atherosclerosis was observed. Treg and sCD25 levels were increased 1 month after CS versus baseline values and versus data in the control group (coronary angiography [CA], n = 20). A positive correlation between Treg and sCD25 levels was reported, whereas no relation was observed with the length of SES implanted. HsCRP level was increased during the first 7 days and returned to baseline values 1 month after CS/CA. Treg content is lower in patients with multivessel CAD. Elevated levels of Tregs and sCD25 after SES implantation might occur because of the immunomodulating effect of rapamycin., (Copyright © 2011 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)

The time course of inflammatory reaction markers in the blood of patients with unstable angina was studied during therapy including arixtra. Plasma concentration of monocytic chemotaxic protein-1 (MCP-1) decreased on days 2 and 3 in patients receiving arixtra and a trend to an increase in MCP-1 concentration was observed on day 7 after the drug was discontinued. After 1 month, MCP-1 level decreased in all patients. The concentration of highly sensitive C-reactive protein also decreased 1 month after the disease onset; no changes in the concentrations of IL-8 and IL-2 receptor α-subunit were detected during these periods. It seems that arixtra is characterized by an anti-inflammatory effect manifesting by reduction of plasma chemokine MCP-1 concentration.

We studied dynamics of content of subpopulation of lymphocytes including regulatory and effector T-lymphocytes as well as concentration of soluble form of interleukine-2 receptor (sCD25) in peripheral blood of patients after coronary stenting (CS) with implantation of stents with rapamycin covering (SRC). We included into the study 62 patients with stable effort II-III functional class angina. Coronary angiography (CA) was carried out in all, CS with implantation of 1 - 2 SRC - in 42 patients. Blood samples were taken before CA/CS, in 24, 48 hours, 7 days, 1 and 3 months after intervention. Content of T-, helper and cytotoxic T-cells, -, NK-, NKT-cells, activated effector T-lymphocytes (CD4+CD251owCD127high) and regulatory T-lymphocytes (CD4+CD25highCD1271ow) were measured by direct immunofluorescence and flow cytometry. CD4+ lymphocytes were isolated from mononuclear cell fraction of donor blood by magnetic separation. Content of regulatory T-lymphocytes in culture were determined by expression of a specific marker FOXP3+. Concentration of sCD25 was measured by chemiluminescent method. It was shown that content of main subpopulations of lymphocytes in blood changed after CS or CF. Blood content of regulatory T-lymphocytes and sCD25 significantly increased after 7 days and 1 month after CS but not after CA. Plasma sCD25 concentration correlated with content of regulatory T-lymphocytes in 1 month after SRC implantation. During cultivation of CD4+ lymphocytes in the presence of rapamycin we noted antiproliferative effect relative to FOXP3-cells and accumulation of regulatory +-lymphocytes. Thus implantation of SRC in coronary arteries leads to increase of number of circulating regulatory T-lymphocytes and blood concentration of sCD25. Changes of these parameters after CS can reflect peculiarities of local and systemic reaction arising in response to introduction of stent with drug covering and be significant for assessment of prognosis of the disease.

Aim: To study the effect of the anti-inflammatory peptide preparation ingramon on the peripheral blood levels of inflammatory markers in patients with exercise-induced stable angina after coronary stenting (CS)., Subjects and Methods: The investigation enrolled 64 patients with stable angina who had undergone coronary bypass surgery, of them 34 patients received ingramon in addition to standard therapy. The blood levels of high-sensitive C-reactive protein (hs-CRP), fibrinogen, the chemokines MCP-1, IL-8, IP-10, and MID were measured before and 1, 2, and 7 days and 1, 3, and 6 months after surgery. Twenty patients who had gone coronarography (CG) only were examined as a control group., Results: In the post CS patients receiving only standard therapy, the levels of hs-CRP and fibrinogen were much higher on days 1, 2, and 7 after surgery than in the CG patients. On day 1 following CS, the increment in hs-CRP correlated with the length of implanted stents. During ingramon therapy, the content of hs-CRP and fibrinogen was considerably lower on days 1, 2, and 7 after CS than in the control group; this trend persisted a month after surgery; there was also a reduction in MCP-1 levels within the first 24 hours after initiation of therapy. The levels of the chemokines IP-10, MIG, and IL-8 were significantly unchanged. CONCLUSION. When added to standard therapy, ingramon exerts a positive effect against risk factors for coronary heart disease (CHD) and its events. Further investigations are required to define the impact of ingramon therapy on prognosis in patients with CHD.

The content of marker foxp3 of regulatory T cells and chemokines in atherosclerotic plaques of human coronary arteries was measured by the polymerase chain reaction. In vitro migration of regulatory CD4(+)CD25(+)foxp3(+) cells in the CD4(+) lymphocyte population from healthy donors was studied after treatment with chemokines I-309, IP-10, and SDF-1. mRNA for the factor foxp3 and chemokines SDF-1, I-309, and MIP-1beta were found in the majority of samples from atherosclerotic plaques. SDF-1 induced maximum migratory response of CD4(+)CD25(+)foxp3(+) cells.

A new anti-inflammatory peptide X (Ingramon)--a fragment of C-terminal sequence (65-76) of MCP-1, was elaborated. In Boyden chamber assay, Ingramon inhibited migration of human monocytic cells THP-1 and peripheral blood monocytes. In vitro in blood plasma, Ingramon was stable for at least 24 hours. Ingramon was accumulated in sites of inflammation in rats, and impaired monocyte and granulocyte accumulation occurred in different models of inflammation in rodents and primates. Ingramon exerted no effect on the MCP-1-dependent externalisation of p2 integrins CD lib CD18 (Mac-1). We propose that Ingramon might interfere with MCP-1-heparin/heparan sulphate binding on cell surface. Ingramon reception by volunteers showed its safety. The clinical trials of Ingramon in patients with acute coronary syndromes and percutaneous coronary interventions, have been launched.

The effects of the synthetic monocyte chemotactic protein-1 (MCP-1) peptide fragment 65-76 (peptide X) on the development of neointima after balloon injury to the carotid artery were studied. The agent was given i.m. at a dose of 33 microg/kg once daily for 28 days after balloon injury. Animals given peptide showed significant suppression of neointima growth 4 and 7 days after lesioning, as indicated by morphometric analysis of sections of lesioned arteries. On days 14 and 28, there were no significant differences in neointima formation in rats given and not given peptide. Peptide administration was not accompanied by any changes in C-reactive peptide concentrations, leukocyte counts, or the population composition of peripheral blood lymphocytes. Use of synthetic peptide X as an inhibitor of leukocyte migration during angioplasty may, along with traditional treatments, decrease the risk of restenosis.

Aim: To investigate the effects of coronary stenting with rapamycin-eluting stents on parameters of cell immunity., Methods: 26 patients (group 1) with stable coronary heart disease and angiographically proved coronary stenosis underwent stenting with rapamycin-eluting stents. The control group (group 2) consisted of 6 patients: 4 patients underwent diagnostic coronaroangiography, I patient got a bare metal stent and in 1 patient angioplasty was unsuccessful. Blood samples were obtained before and 1 month after the intervention. The quantity of activated (CD4+CD25low+) and regulatory (CD4+CD25high+) T cells was measured by direct immunofluorescence and flow cytometry. Plasma concentration of IL-10 was determined by ELISA., Results: In group 1 the percentages of CD4+CD25high+ regulatory T-cells increased significantly one month after stenting, while in group 2 no difference in regulatory T-cell levels before and after the intervention was observed. No changes in total number of leukocytes, relative levels of lymphocytes, CD4+ T-cells, activated CD4+CD25+low T-cells and IL-10 plasma concentration before and after the procedure were detected in both groups., Conclusion: Rapamycin-eluting stent implantation is associated with a significant increase of circulating CD4+CD25high+ regulatory T-cell level.

Aim: To analyse contents of leukocytes and chemokines expression cytokines and transforming growth factor beta (TGFB) in atherosclerotic plaques (AP) of coronary arteries and aortic intima of patients with coronary artery disease (CAD)., Material and Methods: The samples of aortic intima and coronary artery tissues were obtained intraoperatively (coronary artery bypass grafting, endarterectomy). Leukocytes were typed immunohistochemically and cytometry in the flow. Gene expression was analysed using reverse transcription and polymerase chain reaction., Results: AP of the coronary arteries and macroscopically unaffected fragments of aortic imtima contained leukocytes. All the samples contained mRNA of chemokines SDF- 1 and MCP-3. Two groups of the plaques were identified by chemokines expression. Group I AP had marked expression of TGFB, chemokines SDF-1, MCP-3, MIG, I-309, MCP-1, MIP-1beta, I-TAC, RANTES and IL-13. Group II AP had mRNA of the proteins only in single samples. Intima samples free of morphological signs of atherosclerotic lesion contained mRNA of proinflammatory chemokines MIG, I-309, IL-13, had no expression of TGFB., Conclusion: In IHD patients arterial intima free of macroscopic visual affection may be a site of developing inflammation. AP differ by chemokines expression, cytokines, TGFB. The differences may indicate different stages or mechanisms of AP formation.

Influence of synthetic fragment 65-76 of monocyte chemoattractant protein-1 (MCP-1) (peptide X) on development of neointima after balloon injury of carotid artery was investigated. Peptide X was introduced intramuscularly, 33 pg/kg, daily during 28 days after balloon injury. In days 4 and 7 after intervention, in animals receiving peptide X in comparison with control animals a substantial decrease of neointimal growth was observed. On 14 and 28 days there, was no significant difference in neointima development in rats with and without peptide treatment. Injections of peptide X did not after the C-reactive protein concentration, leukocyte number and lymphocyte subpopulations in peripheral blood. Peptide X treatment along with traditional therapy may be effective in preventing restenosis after angioplasty.

Inflammation plays an important role in vessel wall remodeling that occurs in atherosclerosis and postangioplasty restenosis. Monocytic chemoattractant protein-1 (MCP-1) is one of the main attractors of monocytes and some lymphocyte subsets to the damaged vessel. The aims of the study were to confirm MCP-1 participation in the development of acute coronary syndromes, to produce the potential MCP-1 peptide antagonist, and to investigate its effects in vitro and in vivo in different animal models of inflammation. MCP-1 plasma concentration was measured by ELISA (enzyme-linked immunosorbent assay). Chemokine receptor expression by cells isolated from human atherosclerotic lesions was assessed by direct immunofluorescence and flow cytometry. MCP-1 sequence was analyzed with Peptide Companion software and peptides were synthesized using Fmoc strategy. The peptide resistance to degradation was checked by 1H-NMR spectroscopy. The peptide effect on MCP-1-stimulated cell migration was studied in Boyden chamber and in mouse air pouch model, and its influence on lipopolysaccharide (LPS)-induced inflammatory cell recruitment was investigated in models of subcutaneous inflammation in rats and nonhuman primates. We revealed nearly a 2-fold increase of MCP-1 plasma level in patients with unstable angina in comparison with patients with stable angina. The atherosclerotic plaque specimens obtained from patients with unstable angina contained a significant amount of chemokine receptor-expressing leukocytes. Peptide from MCP-1 C-terminal 65-76 sequence (peptide X) inhibited MCP-1-stimulated monocytic cell migration in vitro and in vivo. Peptide X labeled with 99mTc accumulated specifically at sites of inflammation in rats. Peptide X administrated i.m and i.v. suppressed monocyte and granulocyte recruitment induced by subcutaneous injection of LPS in the back of rats and non-human primates. Our data demonstrate that MCP-1-mediated chemotaxis could be responsible for atherosclerotic plaque "destabilization". Peptide X may represent a new class of anti-inflammatory drugs to be used in cardiology.

The retro-enantio analogue of peptide 66-77 of the chemokine MCP-1 and two hexapeptide fragments 66-71 and 72-77 of the C-terminal sequence of this protein were synthesized using the Fmoc strategy of solid phase peptide synthesis. The effect of the synthetic peptides upon the MCP-1-stimulated migration of THP-1 mononuclear cells was studied in vitro. The activity of the retro-enantio analogue was found to be comparable with that of the initial peptide 66-77: both peptides inhibit the migration of monocytes and granulocytes into inflammation zones of experimental animals.

Aim: To estimate concentrations of C-reactive protein (CRP) and MCP-1 in blood plasma of patients with unstable angina (UA) and stable effort angina (SEA)., Material and Methods: Multiprojection coronaroangiography was performed in 12 patients with UA and 11 patients with SEA. Hemodynamically significant stenosis (50% and more) at least in one major coronary artery was confirmed in all the patients. CRP and MCP-1 were measured with latex agglutination and enzyme immunoassay (Biosource kits), respectively., Results: UA patients had significantly higher plasma levels of MCP-1 and CRP than those with SEA (107.25 +/- 16.19 vs. 63.0 +/- 16.16 pg/ml and 1.99 +/- 1.64 vs 0.44 +/- 0.28 mcg/ml, respectively)., Conclusion: Estimation of MCP-1, as a marker of vascular wall inflammation, can be used, in line with other indices, for verification of UA.

Monocyte chemoattractant protein-1 (MCP-1) is important in attracting monocytes to sites of inflammation. Besides induction of monocyte recruitment, MCP-1 can also affect chemotactic response of endothelial cells. The molecular mechanisms involved in MCP-1-induced cell migration are poorly understood. In the current investigation, we demonstrate activation of p42/44(ERK1/2) and p38 mitogen-activated protein kinases (MAPKs), phosphatydilinositol-3-kinase (PI3K) and Src-kinases in both monocytes and endothelial cells stimulated with MCP-1 in vitro. The response was rapid and time-dependent, detectable within 3 min of MCP-1 stimulation. MCP-1-induced phosphorylation of p42/44(ERK1/2) MAPKs was partially blocked by inhibitor of PI3K LY294002, while phosphorylation of p38 MAPK was diminished to a greater extent in presence of Src-kinase inhibitor PP2. There was a substantial inhibition of monocyte migration upon treatment with inhibitors of p38 MAPK, at the same time inhibition of p42/44(ERK1/2) MAPK activation had no effect. On the contrary, the MCP-1-stimulated chemotaxis of endothelial cells was completely abolished by inhibitors of PI3K and p42/44(ERK1/2), but not by p38 MAPK inhibitors. These results suggest that parallel signal transduction pathways are activated by MCP-1, and that depending on the cell type these pathways differentially contribute to cell chemotactic activity.

The intracellular signal cascades involved in chemokine-stimulated migration of in vitro activated human peripheral blood CD4+ T-lymphocytes were investigated. IP-10-mediated chemotactic response of lymphocytes was decreased in the presence of selective inhibitors of Src-kinases (by 40-45%), PI3-kinases (35-40%), and MAP-kinases ERK1/2 (35-40%) and p38 (20%). Combined addition of specific inhibitors of Src-kinases and PI3-kinases and inhibitors of Src-kinases and ERK1/2 MAP-kinases did not result in the further increase of the inhibitory effect, while the combined addition of specific inhibitors of PI3-kinases and ERK1/2 MAP-kinases decreased migration of CD4+ T-lymphocytes more effectively (by 55-60%) than any individual inhibitor. Immunoblotting analysis of activation of MAP-kinases ERK1/2 and p38 revealed increased level of phosphorylation of ERK1/2 and p38 MAP-kinases in the presence IP-10. Selective inhibitors of Src-kinases and PI3-kinases significantly inhibited phosphorylation of p38 but did not influence phosphorylation of ERK1/2 MAP-kinases. Our results suggest that Src-kinases, PI3-kinases, and ERK1/2 MAP-kinases are involved in intracellular signal cascade activated during IP-10-stimulated migration of T-lymphocytes, whereas p38 MAP-kinases do not participate in the migration process, although its activation induced by IP-10 depends on Src-kinases and PI3-kinases.

Aim: To study the condition of the sympathico-adrenal system (SAS), synthesis of cAMP dependent on beta2-adrenoreceptors and parameters of free radical oxidation in patients with primary pulmonary hypertension (PPH); to examine efficacy of non-selective beta- and alpha1-adrenoblocker carvedilol in PPH patients., Material and Methods: Twenty patients with PPH had 6-minute walk test, ECG monitoring with assessment of heart rhythm variability (HRV). Tests for noradrenalin and adrenalin concentration in blood plasma, cAMP synthesis by blood lymphocytes in basal conditions and under stimulation with isoproterenol and forskolin, free radical oxidation were made initially, 1 and 6 months later. Ten patients received carvedilol in addition to standard therapy, 10 patients served control., Results: PPH patients had higher NA in the blood, low cAMP synthesis, high malonic aldehyde, low activity of glutathionperoxidase, increased activity of superoxidedismutase and catalase of erythrocytes. The most pronounced changes in the above parameters were observed in patients with PPH FC III-IV. HRV declined in progression of cardiac failure. 6-months of combined treatment with carvedilol increased the distance of 6-min walk. Carvedilol had no effect on HRV, it reduced NA, stimulated cAMP synthesis, demonstrated no antioxidant activity., Conclusion: In PPH there is activation of SAS and desensitization of beta2-AR cells, oxidative stress develops. Addition of carvedilol to standard therapy with PPH improves clinical condition due to adrenoblocking properties of the drug.

Fourteen fragments and structural analogues of chemokine MCP-1 were synthesized using the Fmoc strategy of solid phase peptide synthesis. The effect of synthesized peptides on the MCP-1-stimulated migration of mononuclear cells was examined. Both in vitro stimulants and inhibitors of the monocyte migration were found among the peptides. A possible participation of the C-terminal part of the MCP-1 molecule in the inhibition of the MCP-1-stimulated cell migration was found for the first time. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2004, vol. 30, no. 6; see also http://www.maik.ru.

MCP-1-stimulated chemotaxic response of monocytic cell line THP-1 and peripheral blood monocytes were investigated through extra cellular matrix proteins fibronectin, fibrinogen and fibrinogen degradation products. Cellular migration was significantly decreased in the presence of fibrinogen as compared with fibronectin. Fibrinogen proteolysis with plasmin generating D and E degradation products, resulted in increase of the chemotaxic response.

Monocyte chemoattractant protein (MCP-1) is a major chemoattractant for monocytes and T-lymphocytes although it can cause migration of the HUVECs. We used monocytic cell line THP-1, monocytes of human peripheral blood, and HUVECs to study MCP-1 receptor-mediated cell migration. We showed that THP-1 and the monocytes chemotaxis was decreased in presence of specific inhibitors of p 38 MAP-kinase. Furthermore, it was almost completely diminished by inhibitor of tyrosine kinases. In contrast, MCP-1-stimulated migration of HUVECs was abrogated by specific inhibitor of ERK1/2 MAP-kinases and, to a lesser extent, by blocking tyrosine kinases. These results suggest that intracellular signal pathways activated by MCP-1 in monocytes and HUVECs, are distinct.

Aim: To examine expression of superficial antigens by blood monocytes and granulocytes as well as the number of leukocyte-platelet complexes forming in in vitro activation in patients subjected to coronary angioplasty; to analyse changes in these parameters in coronary restenosis., Material and Methods: Membrane expression of leukocytic antigens and the number of leukocyte-platelet complexes after activation in the whole blood were measured by direct immunofluorescence and flow cytometry in 24 patients who have undergone stenting of coronary arteries. 14 of them had angiographically confirmed restenosis., Results: The tests discovered high expression of integrins Mac-1 and VLA-4 by monocytes and elevated relative number of monocyte-platelet complexes in patients with restenosis vs those free of stenosis (1425 +/- 76 and 1195 +/- 71 r.u. for Mac-1, 87 +/- 7 and 65 +/- 6 r.u. for VLA-4, 47 +/- 4 and 29 +/- 3%, respectively, for monocyte-platelet complexes; p < 0.05 for all the indices)., Conclusion: Coronary restenosis may result from elevated expression of adhesion molecules by monocytes manifest in activation of the cells in vitro.

Aim: To evaluate carvedilol effect on clinical state, norepinephrine (NE) and epinephrine (E) plasma concentration and lymphocyte beta 2-adrenoreceptor dependent cAMP synthesis in patients with primary pulmonary hypertension (PPH)., Material and Methods: 14 patients with PPH were included in the study; 9 patients were treated by carvedilol; 5 patients were in the control group. The primary efficiency parameters were submaximal exercise measured by 60 min walk test, systolic pulmonary artery pressure (SPAP) measured by Doppler echocardiography, heart rate (HR) measured by 24-hour ECG-monitoring., Results: One month carvedilol treatment of PPH patients resulted in a significant HR reduction. There was a tendency to SPAP decrease, the 6-minute walk test results improved in IIINYHA patients., Conclusion: Carvedilol therapy improves clinical state and evoked lymphocyte beta 2-adrenoceptor resensitization in PPH patients.

Aim: To evaluate norepinephrine (NE) and epinephrine (E) plasma concentration and lymphocyte beta-2-adrenoceptor dependent cAMP synthesis in primary pulmonary hypertension (PPH) patients in comparison with healthy controls., Material and Methods: Seven volunteers and fifteen patients with PPH were included in the study. NE and E plasma levels were measured by high performance liquid chromatography. Basal and stimulated (isoproterenol and forskolin) adenylyl cyclase activity in lymphocytes was measured by cAMP production using an enzyme immunoassay (Biotrak, Amersham UK)., Results: There was a 110% (p = 0.001) NE level increase in PPH patients. In systolic pulmonary artery pressure (SPAP) > 95 mm Hg lymphocyte cAMP production associated with adenylyl cyclase catalytic subunit was decreased by 170% and 70% vs PPH patients with SPAP < 95 mm Hg and healthy controls, respectively (p < 0.05). A significant negative correlation between forskolin cAMP production by lymphocytes and SPAP level was observed in PPH patients (k = -0.810, p = 0.011 by Kendell; k = -0.893, p = 0.007 by Spirman). Heart failure progressing from I-II to III NYHA functional classes was accompanied by plasma NE enhance and lymphocyte beta-2-adrenoreceptor-activated cAMP production decrease., Conclusion: The data demonstrate sympathoadrenal system activation and lymphocyte beta-2-adrenoceptor desensitization in PPH patients.

1. In the present study, we sought to determine whether patients with restenosis after coronary stenting possess increased monocyte reactivity, as manifested by a higher level of adhesion molecule expression and an enhanced propensity to form monocyte-platelet aggregates after activation in vitro. 2. Anti-coagulated peripheral venous blood from 24 patients, 10 with and 14 without angiographically verified restenosis, was obtained. Leucocyte antigen expression and the number of leucocyte-platelet complexes were measured by flow cytometry after activation in whole blood. 3. Surface integrin Mac-1 (CD11b/CD18) and VLA-4 (CD49d/ CD29) expression on monocytes and the relative number of monocyte-platelet complexes after in vitro activation were significantly elevated in patients with restenosis compared with patients without restenosis (fluorescence intensities of 1425 +/- 76 vs 1195 +/- 71, 87 +/- 7 vs 65 +/- 6 and 47 +/- 4 vs 29 +/- 3% for for Mac-1, VLA-4 and monocyte-platelet complexes, respectively; P < 0.05 for each parameter). 4. The results suggest that restenosis is associated with increased monocyte VLA-4 and Mac-1 integrin expression and monocyte-platelet complex formation, which can be revealed after activation in vitro.

beta(2)-integrin Mac-1 and immunoglobulin-like ICAM-1 adhesion molecules are expressed by monocytes and both known to bind fibrinogen and its degradation products. Here, we investigated whether fibrinogen cleavage with plasmin modulates the adherence of monocytic cells and what types of adhesion molecules are involved. Using several cell types, characterized by different patterns of Mac-1 and ICAM-1 expression, and monoclonal antibodies against beta(2)-integrins and ICAM-1 we demonstrate, that fibrinogen cleavage evokes gradual decrease in beta(2)-integrin-dependent cell adhesion. Furthermore, generation of the early degradation products, fragments X and Y, by minimum cleavage of fibrinogen stimulates cell adhesion, mediated by ICAM-1., (Copyright 2001 Wiley-Liss, Inc.)

Monocytic cell adhesion to immobilized fibrinogen and fibrinogen degradation products, and involvement of integrins Mac-1 and immunoglobulin-like ICAM-1 adhesion molecules in these processes were investigated. Fibrinogen cleavage with plasmin down-regulated adhesion of cells with predominant Mac-1 expression; in contrast, the attachment of ICAM-1-expressing was up-regulated. By means of function-blocking anti-Mac-1 and anti-ICAM-1 antibodies, and immobilization of known fibrinogen degradation products, it was shown that Mac-1 molecules mediated cell adhesion predominantly to fibrinogen, and its early degradation products, fragments X and Y, while ICAM-1 participated in cell attachment to X- and Y-fragments, rather than to intact fibrinogen or late degradation products, fragments D and E.

Both spontaneous and endotoxin-induced tissue factor expressions were not altered by exogenous urokinase. Inhibition of endogenous urokinase and plasmin did not affect the endotoxin-induced monocyte tissue factor's activity.

Urokinase activates adhesion of monocytic U937 cells to fibrinogen-coated surface. This effect is due to urokinase proteolytic activity and does not depend on the urokinase binding to its receptor.