Study of nano-fiber cellulose production by Glucanacetobacter xylinum ATCC 10245.

Bacterial Celluloses (BC) are gaining importance in research and commerce due to numerous factors affecting the bacterial cellulose characteristics and application in different industries. The aim of the present study was to produce bacterial cellulose in different media using different cultivation vessels. Bacterial cellulose was produced by static cultivation of Glucanacetobacter xylinum ATCC 10245 in different culture media such as Brain Heart Agar, Luria Bertani Agar /Broth, Brain Heart Infusion, Hestrin-Schramm and medium no. 125. Cultivation of bacterium was conducted in various culture vessels with different surface area. The cellulose membrane was treated and purified with a 0.1 M NaOH solution at 90 degreesC for 30 min and dried by a freeze- drier at -40 degreesC to obtain BC. The prepared bacterial cellulose was characterized by scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy and X-ray diffraction (XRD). The amount of produced BC was related directly to the surface area of culture vessels.

Optimization of culture medium to increase the production of desferrioxamine B (Desferal) in Streptomyces pilosus.

The aim of this study was optimization of culture medium in direction of increasing the production rate of desferrioxamine B. Streptomycetes are the most widely studied and well known genus of the actinomycete family. Streptomycetes usually inhabit soil and are important decomposers. The genus Streptomyces are Gram-positive and GC rich bacteria that are important for production of many antibiotics and secondary metabolites. These metabolites are important in industrial and medical fields. Deferoxamines (also known as desferrioxamine B, desferoxamine B, DFO-B, DFOA, DFB or desferal) are low-molecular-weight, iron-chelating compounds (siderophores) produced and secreted by many actinomycetes, including species of Streptomyces, Nocardia and Micromonospora. Streptomyces pilosus synthesizes the siderofore desferrioxamine B. Desferrioxamine B is used clinically to treat disorders related to iron overload and pathological iron deposition in human. Our results revealed that the use of soybean as a base medium plus additives such as Na2HPO4.12H2O, NaH2PO4, MgSO4.7H2O, ZnSO4.7H2O, FeSO4.7H2O, CaCl2.2H2O, NaCl, MnSO4, NH4Cl, KH2PO4, K2HPO4, some of the amino acids and vitamins increased the production of desferrioxamine B about 8 times in comparison with the control.

Safety of human therapeutic morphine vaccine employing Lohmann specific pathogen free eggs.

One of the sensitive and standard tests to control the safety of a vaccine is the inoculation of such vaccine to the air pocket of Lohmann specific pathogen free eggs. The aim of this study is to control the safety of morphine vaccine. This study reveals the safety of morphine vaccine by employing Lohmann specific pathogen free embryo eggs. The changeable parameters in this test were: weight of eggs, safety of eggs embryo, vaccine concentration, normal saline and temperature of the incubator. To study, the safety of morphine vaccine, we used 30 eggs (after controlling the safety of eggs and their embryos) which were divided into two groups of control (15 eggs) and test (15 eggs). After weighing the eggs, the eggs under experiment were inoculated with morphine vaccine and the control group was inoculated with physiological solution. Both groups were incubated and weight of the eggs and chickens were determined accordingly. The eggs of each group were controlled by their weights showing healthy, normal growth and evolution. The comparison between the weights of control and experimental groups did not show any significant changes. Exactly growth and evolution of each group were found equally to be balancing for three weeks after injection. Finally all eggs were observed to be safe, alive and in evolutionary form. By comparing the growth and evolution amongst each egg in the group under experiment, after injection, the eggs did not show any adverse reaction after inoculation with therapeutic human morphine vaccine.

Production of desferrioxamine B (Desferal) using corn steep liquor in Streptomyces pilosus.

The aim of this study was evaluation of corn steep liquor as an alternative or substitution medium for production of desferrioxamine B in streptomyces pilosus. Desferrioxamine B is the major siderophore of Streptomyces pilosus. The genus Streptomyces are Gram positive and GC (Guanine/Cytosine) rich bacteria that are important for production of many antibiotics and secondary metabolites. These metabolites get more attention in industrial and medical fields. Desferrioxamine B is used clinically to treat disorders related to iron overload and pathological iron deposition in human. Corn Steep Liquor (CSL) is a by-product of corn wet-milling. It is an excellent source of organic nitrogen and important constituent of some culture media. Nowadays CSL was mainly used for feeding of livestock. In this study we substitute the conventional media with CSL and surveyed its effect on production of desferrioxamine B. The CSL is cheaper than other media and its availability is so easy. In this research, for the first time we used a cheap material for production of a valuable product. Our results showed that the use of CSL solely, increased the production of Desferal more than three times in comparison with conventional media such as soybean.

Improved production of L-lysine by over-expression of Meso-diaminopimelate decarboxylase enzyme of Corynebacterium glutamicum in Escherichia coli.

The aim of this study is over-expression of Meso-diaminopimelate decarboxylase enzyme (EC 4.1.1.20) and enhancement of L-lysine production rate. The C. glutamicum LysA gene which encodes a Meso-diaminopimelate decarboxylase was cloned in E. coli. The cloned gene was sequenced; it encodes a 445 amino acids protein with molecular weight of 47 kD. Expression of the LysA gene in E. coli resulted in an increase in Meso-diaminopimelate decarboxylase activity, correlated with the presence in sodium dodecyl sulfate-polyacrylamid gels of a clear protein band that corresponds to this enzyme. The induction of cloned gene by IPTG has been shown to have an inhibitory effect on cell growth due to over-expression of the cloned gene. A two fold increase in lysine production rate was observed after introduction of the cloned gene into E. coli.

The effect of iron deficiency anemia on intelligence quotient (IQ) in under 17 years old students.

The aim of this study was to evaluate the effects of iron deficiency on intelligence of 11-17 years students. This study conducted on the 540 students (11-17 years) that educated at guidance and high school of Boroujerd city. Laboratory investigations were included serum iron, TIBC (total iron binding capacity) and ferretin. Riven matrix was used in order to determine intelligence quotient. Data were analyzed using SPSS 13 and chi2 and t-tests. Results showed that 78 (14.4%) students had iron deficiency and 14 (25.9%) had iron deficiency anemia. There was no significant difference between different sexes for iron deficiency distribution (p > 0.05), while iron deficiency anemia was significantly higher in girls as compared with boys (p > 0.05). Mean quotient was 115 +/- 12.1 in iron deficiency students, while it was 113.7 +/- 13.9 in patients without iron deficiency. There was also no significant difference between normal and iron deficient students for intelligence quotient (p > 0.05).

Mutation of Streptomyces griseoflavus in order to obtain high yield desferrioxamine producing fused cells.

Streptomyces griseoflavus PTCC 1130 was mutated by UV irradiation. Two mutants were obtained (C7031 and S7011). These two mutants were able to produce desferioxamine. Desferrioxamine was extracted from the culture broth of the two mutated strains and the thin layer chromatogram of the products showed the R(F) values of 0.461, 0.463 and 0.456 for S7011, C7031 and the standard, respectively. The protoplasts of mutated Streptomyces griseoflavus were isolated and fused together. Total numbers of 58 fusions were obtained and only 17 fusions showed significant resistance to sodium azide and crystal violet. In terms of production of desferrioxamine only fusion PF9 and PF10 increased 68.3 and 81.8% desferrioxamine production as compared to parent strain (PTCC 1130), respectively.

Treatment of streptozotocin induced diabetes in male rats by immunoisolated transplantation of islet cells.

Insulin injection is the main way to combat against insulin-dependent diabetes mellitus effects. Today in some laboratories in the world, the investigators are trying to find some treatments for this disease with insulin-secreting pancreatic islet cells transplantation. Donor tissue in each step of work was prepared from 36 adult male wistar Rats weighted 250-300 grams (75-90 days). Transplantation was done in rats after 2-4 weeks induction of diabetes with 60mg/kg of streptozotocin injection by intravenous method. Encapsulation of pancreatic islet cells allows for transplantation in the absence of immunosuppression. This technique that is called "immunoisolation" is based on the principle that transplanted tissue is protected for the host immune system by an artificial or natural membrane. In this study, the levels of insulin, C-peptide and glucose in diabetic rats have been reached to normal range as compared to un-diabetic rats in 20 days after transplantation of islet cells, so that testis is immunoisolated place for islet cells transplantation. Inside the testis subcutaneously and intrapretoneally implantation of pure islet cells graft, that is a natural immunoisolation method, rapidly and permanently normalized the diabetic state of streptozocin-administered animals.

Induction of diabetes by Streptozotocin in rats.

The objective of this study is to induce experimental diabetes mellitus by Streptozotocin in normal adult Wistar rats via comparison of changes in body weight, consumption of food and water, volume of urine and levels of glucose, insulin and C-peptide in serum, between normal and diabetic rats. Intra-venous injection of 60mg/kg dose of Streptozotocin in adult wistar rats, makes pancreas swell and at last causes degeneration in Langerhans islet beta cells and induces experimental diabetes mellitus in the 2-4 days. Induction of experimental diabetes mellitus is indeed the first step in the plan of purification of pancreatic Langerhans islet cells of normal rats for transplanting under the testis subcutaneous of experimentally induced diabetic rats. Streptozotocin induces one type of diabetes which is similar to diabetes mellitus with non-ketosis hyperglycemia in some animal species. For induction of experimental diabetes in male adult rats weighted 250-300 grams (75-90 days), 60mg/kg of Streptozotocin was injected intravenously. Three days after degeneration of beta cells, diabetes was induced in all animals. The diabetic and normal animals were kept in the metabolic cages separately and their body weight, consumption of food and water, urine volume, the levels of serum glucose, insulin and C-peptide quantities in all animals were measured and then these quantities were compared. For a microscopic study of degeneration of Langerhans islet beta cells of diabetic rats, sampling from pancreas tissue of diabetic and normal rats, staining and comparison between them, were done. Induction of diabetes with Streptozotocin decreases Nicotinamide-adenine dinucleotide (NAD) in pancreas islet beta cells and causes histopathological effects in beta cells which probably intermediates induction of diabetes. In this study, we used Streptozotocin for our experiments in induction of experimental diabetes mellitus. After Induction of diabetes, consumption of food and water, volume of urine and glucose increased in the diabetic animals in comparison with normal animals, but the weight of body and the volume of insulin and C-peptide decreased in the diabetic animals. Sampling and staining of pancreas tissue of diabetic and normal rats showed that the Langerhans islet beta cells of diabetic rats have been clearly degenerated. In three days, Streptozotocin makes pancreas swell and at last causes degeneration in Langerhans islet beta cells and induces experimental diabetes. It also changes normal metabolism in diabetic rats in comparison with normal rats. Consumption of water and food, volume of urine, serum glucose increases in diabetic animals in comparison with normal rats but the levels of serum insulin, C-peptide and body weight decreases.

Enhanced accumulation of the isoprostane, 8-epi-PGF2 alpha, in human aortic and pulmonary valves of patients with coronary heart disease.

The aim of the present study was to investigate whether the isoprostane 8-epi-PGF2 alpha differently accumulates in semilunar valves of patients suffering from coronary heart disease (CHD, n = 19) as compared to valves from healthy heart donors (controls, n = 6). Sections from isolated aortic and pulmonary valves were analyzed by semiquantitative immunohistochemistry. The 8-epi-PGF2 alpha-content was determined by using a specific radioimmunoassay. The accumulation of 8-epi-PGF2 alpha in both valves was higher in CHD-patients in comparison to controls (Aortic valves: 36.49 +/- 11.26% vs. 15.78 +/- 3.04%; pulmonary valves: 46.79 +/- 9.80% vs. 14.99 +/- 3.57%). The results from the radioimmunoassay revealed comparable findings in both groups (CHD vs. controls: 395.95 +/- 86.09 vs. 139.50 +/- 47.46 pg/mg protein in the aortic valves and 430.47 +/- 76.30 vs. 147.33 +/- 53.84 pg/mg protein in pulmonary valves). Pulmonary valves seem to be more susceptible to oxidative stress than aortic valves as evidenced by a higher accumulation of 8-epi-PGF2 alpha in CHD patients. Considering the data presented in this study, we suggest that 8-epi-PGF2 alpha is a valuable indicator of oxidative injury in human semilunar valves.

Expression of the MT1 melatonin receptor subtype in human coronary arteries.

Previous experimental data suggest a possible influence of melatonin on the circulatory system of animals after binding to G-protein coupled melatonin receptors. The present study sought to investigate whether the melatonin receptor, mt1, is expressed in human coronary arteries derived from healthy heart donors (n = 8). Expression of the mt1-receptor was studied in sections of isolated coronary arteries by a reverse transcriptase-polymerase chain reaction (RT-PCR) and Western immunoblot technique. The analyses of the results from both methods indicated the presence of the mt1-receptor in all of the subjects. Referring to these data we assume that melatonin regulates physiological processes in human coronary arteries after receptor binding.

The isoprostane 8-epi-PGF(2alpha) is a valuable indicator of oxidative injury in human heart valves.

To date, little information is available concerning oxidative injury in human cardiac valves. Therefore, we sought to investigate whether the isoprostane, 8-epi-PGF(2alpha), a novel oxidative stress marker, is localized in aortic and pulmonary valves derived from explanted hearts of patients suffering from idiopathic dilative cardiomyopathy (IDC). By using semiquantitative immunohistochemistry, we demonstrated that 8-epi-PGF(2alpha) is localized in both valves with pulmonary valves accumulating more of this isoprostane compared to aortic valves (36.69+/-12.04% vs. 31.54+/-11.49%, P<.05). These results were confirmed by a radioimmunoassay (RIA) analysis showing a similar, but not significant, difference between the two valves (288.50+/-72.18 pg/mg protein in the pulmonary valves and 267.30+/-58.77 pg/mg protein in aortic valves, P=.09). Considering the data presented in this study, we suggest that 8-epi-PGF(2alpha) is a valuable indicator of oxidative injury in human semilunar valves.

Angiogenesis stimulation in explanted hearts from patients pre-treated with intravenous prostaglandin E(1).

BACKGROUND: Prostaglandin E(1) (PGE(1)) is a potent vasodilator and induces angiogenesis in animal tissues. Previous clinical studies demonstrated that PGE(1) improves hemodynamic parameters in patients with heart failure listed for heart transplantation (HTX). Therefore, we designed a retrospective immunohistochemistry study to investigate various markers of angiogenesis using hearts explanted from PGE(1)-treated patients with idiopathic dilated cardiomyopathy (IDCM). METHODS AND RESULTS: We investigated neovascularization in 18 hearts explanted from patients with IDCM: 9 patients received treatment with chronic infusions of PGE(1) for end-stage heart failure before HTX, whereas the remaining patients with IDCM did not receive PGE(1) and served as controls. We used immunoreactivity against CD34, von Willebrand factor (vWf), vascular endothelial growth factor (VEGF), and MIB-1 (Ki-67) to quantify angiogenesis, and used sirius red staining to determine the degree of fibrosis. Compared with the control group, PGE(1)-treated patients had significantly more CD34-, vWf- and MIB-1-positive cells in the sub-endocardium, myocardium and sub-epicardium (p < 0.01). The degree of fibrosis in the hearts of PGE(1)-treated patients was significantly lower than in control patients (p < 0.05), but we did not see any difference in the percentage of muscle mass. Finally, throughout the ventricles, we found significantly more VEGF-positive capillaries in the PGE(1) group (p < 0.0001). CONCLUSIONS: The data suggest that PGE(1) could be a potent inducer of angiogenesis and the angiogenic factor VEGF, and could cause reduced fibrosis in the failing human heart.

24h variation in the expression of the mt1 melatonin receptor subtype in coronary arteries derived from patients with coronary heart disease.

Previous studies presented evidence for impaired nocturnal secretion and synthesis of melatonin in patients with coronary heart disease (CHD). This study aimed to investigate whether the melatonin receptor subtype mt1 is differentially expressed in coronary arteries derived from patients with CHD (n = 9) compared to patients with dilative cardiomyopathy (CMP; n = 10) who served as controls. Expression of the mt1 receptor was studied in sections of isolated coronary arteries by a reverse transcriptase-polymerase chain reaction (RT-PCR) and a Western immunoblot technique. In addition, the data from the Western blotting of 15 patients were interpolated against the exact time of aortic clamp to study the 24h expression of the mt1 receptor. The analyses of the results from both methods indicated the presence of the mt1 receptor in all of the individuals. No statistically significant difference was observed in the receptor expression between patients with CHD and those with CMP (in arbitrary units: 3.39 +/- 3.08 versus 3.91 +/- 2.78). Expression of the melatonin receptor in the coronary arteries of the whole patient group presented a 24h variation, with the lowest values detectable after 02:00 up to the late morning hours and a progressive increase beginning after 13:00 until 00:00 (mesor = 3.66, amplitude = 3.23, acrophase = 20.45, P = .0003). When studying the 24h variation in patients with CHD and CMP separately, a nearly similar circadian course was observed. In conclusion, we demonstrated for the first time a 24h variation of a melatonin receptor subtype in human vessels. Furthermore, in relation to our results, we suggest that the expression of the mt1 melatonin receptor in the coronary arteries is probably not impaired in patients with CHD.

Accumulation of oxidized LDL in human semilunar valves correlates with coronary atherosclerosis.

OBJECTIVE: Recent data indicate that oxidized low-density lipoprotein (ox-LDL) has several proatherogenic effects, e.g. induction of macrophage chemoattractants, adhesion molecules, cytokines, type-1 plasminogen activator inhibitor and platelet-derived growth factor A-chain by smooth muscle cells. Therefore, ox-LDL has been utilized as a marker of oxidative modification of proteins in atherosclerosis. Because heart valves consist of smooth muscle cells, fibroblasts and endothelial cells, and because valvular disease and coronary atherosclerosis could result from similar biological processes, we investigated ox-LDL accumulation in isolated aortic and pulmonary valves and coronary arteries from patients with angiographically proven coronary heart disease (CHD, n = 19), patients with idiopathic congestive heart failure (IDCM = idiopathic dilated cardiomyopathy, n = 20), and transplant donors. METHODS: Masson-Goldner staining and immunohistochemistry utilizing anti ox-LDL and CD68 were performed on paraffin sections of freshly isolated semilunar valves. Data were analyzed by digital image planimetry and by visual scoring of staining intensity. RESULTS: Ox-LDL immunoreactivity was identified in the vascular aspect of the attachment line, in the deep valve stroma, and in the ventricular and vascular endothelium of the semilunar valves, colocalizing with macrophages. Valvular ox-LDL area was significantly increased in CHD-patients (P < 0.03) and IDCM-patients (P < 0.04) compared with controls. More ox-LDL was accumulating in the pulmonary valves than in the aortic valves (P = 0.04) as assessed by area and staining intensity. Valvular ox-LDL area in pulmonary valve and aortic valve was significantly correlated with ox-LDL accumulation in the intimal layer (P < 0.001) and medial layer (P < 0.001) of coronary arteries from the same patients. CONCLUSION: The data suggest that the biological process leading to ox-LDL accumulation in coronary atherosclerosis also involves heart valves. Therefore, accumulation of the oxidative stress marker ox-LDL in heart valves illustrates atherosclerosis as an additional mechanisms accelerating valvular degeneration in these patients.

Oxidized low-density lipoprotein is localized in the ventricles of hearts from patients with coronary heart disease.

The present study was designed to investigate whether oxidized low-density lipoprotein is accumulated in the left and right ventricular walls of patients with coronary heart disease (n=10) compared with patients with dilated cardiomyopathy (n=9) or healthy heart donors (controls, n=5). Sections from both ventricles of explanted hearts and coronary arteries of the same patients were analyzed by semiquantitative immunohistochemistry for the presence of oxidized low-density lipoprotein. Oxidized low-density lipoprotein was enriched in the left and right ventricular walls from coronary heart disease patients compared with patients with dilated cardiomyopathy (P=0.0012 for left ventricle and P=0.103 for right ventricle) or controls (P=0.0012 for the left ventricle and P<0.05 for the right ventricle). The accumulation of oxidized low-density lipoprotein was higher in the left than in the right ventricles in all three groups. Positive immunoreactivity for oxidized low-density lipoprotein was mainly identified in the endocardium and the subendocardial areas of the ventricles and co-localized with macrophages. Accumulation of oxidized low-density lipoprotein in the ventricles significantly correlated with the enrichment in the respective coronary arteries, whereas only poor correlations were observed between various hemodynamic parameters and ventricular oxidized low-density lipoprotein accumulation. Ventricular accumulation of oxidized low-density lipoprotein seems to be a generalized pathophysiological process which does not exclusively involve the coronary arteries. Higher oxidative stress in combination with impaired oxygen supply in the endocardium could have favored low-density lipoprotein deposition and oxidation.

The isoprostane, 8-epi-PGF2 alpha, is accumulated in coronary arteries isolated from patients with coronary heart disease.

OBJECTIVE: In the present study we wanted to know whether 8-epi-PGF2 alpha, which belongs to the class of isoprostanes formed by free radical-mediated peroxidation of arachidonic acid and arachidonyl-containing phospholipids, is enriched in isolated coronary arteries of patients suffering from coronary heart disease (CHD, n = 23) who received allograft heart transplants as compared to vessels derived from patients with dilative cardiomyopathy (CMP, n = 19) or from healthy heart donors (controls, n = 6). METHODS: Sections from the isolated coronary arteries were analysed by semiquantitative immunohistochemistry by determining the area and intensity of positive reaction for 8-epi-PGF2 alpha in the vascular intima and media. In addition, the 8-epi-PGF2 alpha content was determined using a specific immunoassay after extraction and purification. RESULTS: The immunohistochemical results indicated that 8-epi-PGF2 alpha is significantly enriched in arteries from patients suffering from CHD as compared to CMP (P < 0.0001). In controls, significantly less immunostaining was observed. Furthermore, a significant positive correlation between semiquantitative immunohistochemistry and radioimmunological determination was observed too. CONCLUSIONS: From our findings we conclude that 8-epi-PGF2 alpha is especially accumulated in coronary arteries from CHD patients and therefore is likely to be involved in atherogenesis.

Expression of fibrinolytic antigens in redistributed cardiac mast cells in auricular thrombosis.

Recent data suggest that auricular thrombosis is associated with an increase and accumulation of mast cells (MC) in the subendothelial region of the upper endocardium. However, the molecular basis and the functional role of MC in this process are not known. In the current study, expression of fibrinolytic and antifibrinolytic antigens in human cardiac MC was analyzed by immunohistochemistry. MC were found to react with antibodies against tissue-type plasminogen activator (tPA) and urokinase receptor (uPAR/CD87), but not with antibodies against urokinase (uPA) or plasminogen activator inhibitors (PAI-1, PAI-2). Significant changes were observed when the phenotype of accumulated MC in the upper endocardium in patients with auricular thrombosis was compared with the phenotype of myocardial MC in the same patients or with MC in normal hearts. These redistributed MC stained less intensely with antibodies against tPA and chymase but retained their staining for tryptase and uPAR. Together, these data indicate that cardiac MC are a source of fibrinolytic antigens and that accumulation of MC in auricular thrombosis is associated with phenotypic changes of MC and loss of cellular tPA. It is hypothesized that MC and their products may play a role in endogenous fibrinolysis in auricular thrombosis.

Thrombin augments vascular cell-dependent migration of human mast cells: role of MGF.

Recent data suggest that auricular thrombosis is associated with accumulation of mast cells (MC) in the upper endocardium (where usually no MC reside) and local expression of MGF (mast cell growth factor) (25). In this study, the role of vascular cells, thrombin-activation and MGF, in MC-migration was analyzed. For this purpose, cultured human auricular endocardial cells (HAUEC), umbilical vein endothelial cells (HUVEC) and uterine- (HUTMEC) and skin-derived (HSMEC) microvascular endothelial cells were exposed to thrombin or control medium, and the migration of primary tissue MC (lung, n = 6) and HMC-1 cells (human MC-line) against vascular cells (supernatants) measured. Supernatants (24 h) of unstimulated vascular cells (monolayers of endocardium or endothelium) as well as recombinant (rh) MGF induced a significant migratory response in HMC-1 (control: 3025 +/- 344 cells [100 +/- 11.4%] vs. MGF, 100 ng/ml: 8806 +/- 1019 [291 +/- 34%] vs. HAUEC: 9703 +/- 1506 [320.8 +/- 49.8%] vs. HUTMEC: 8950 +/- 1857 [295.9 +/- 61.4%] vs. HSMEC: 9965 +/- 2018 [329.4 +/- 66.7%] vs. HUVEC: 9487 +/- 1402 [313.6 +/- 46.4%], p < 0.05) as well as in primary lung MC. Thrombin-activation (5 U/ml, 12 h) of vascular cells led to an augmentation of the directed migration of MC as well as to a hirudin-sensitive increase in MGF synthesis and release. Moreover, a blocking anti-MGF antibody was found to inhibit MC-migration induced by unstimulated or thrombin-activated vascular cells. Together, these data show that endocardial and other vascular cells can induce migration of human MC. This MC-chemotactic signal of the vasculature is associated with expression and release of MGF, augmentable by thrombin, and may play a role in the pathophysiology of (auricular) thrombosis.