Improved expression by cytomegalovirus promoter/enhancer and behavior of vascular endothelial growth factor gene after myocardial injection of naked DNA

Direct injection of the vascular endothelial growth factor (VEGF) gene plasmid DNA into the myocardium was shown to induce development of new blood vessels to increase the circulation in the heart of patients with coronary artery diseases. However, such angiogenic gene therapy (via naked DNA) was limited by low level of gene expression. Furthermore, the temporal and spatial characteristics of VEGF gene transfer in the heart are not known. In this study, we demonstrated that a plasmid vector, containing the human cytomegalovirus immediate early (HCMV IE) promoter and enhancer, induces greater expression of gene in the rat heart monitored by gene fused to the chloramphenicol acetyl transferase (CAT) reporter, than four different viral and cellular promoters. Interestingly, expression of VEGF121 protein showed an earlier peak, a shorter duration, and a wider distribution than that of CAT only. Therefore, a plasmid vector with an HCMV IE promoter/enhancer provides clear advantages over other previously developed plasmids. Furthermore, expression profile of VEGF121 gene may provide useful information in the design of angiogenic gene therapy in the heart

Improved expression by cytomegalovirus promoter/enhancer and behavior of vascular endothelial growth factor gene after myocardial injection of naked DNA

Direct injection of the vascular endothelial growth factor (VEGF) gene plasmid DNA into the myocardium was shown to induce development of new blood vessels to increase the circulation in the heart of patients with coronary artery diseases. However, such angiogenic gene therapy (via naked DNA) was limited by low level of gene expression. Furthermore, the temporal and spatial characteristics of VEGF gene transfer in the heart are not known. In this study, we demonstrated that a plasmid vector, containing the human cytomegalovirus immediate early (HCMV IE) promoter and enhancer, induces greater expression of gene in the rat heart monitored by gene fused to the chloramphenicol acetyl transferase (CAT) reporter, than four different viral and cellular promoters. Interestingly, expression of VEGF121 protein showed an earlier peak, a shorter duration, and a wider distribution than that of CAT only. Therefore, a plasmid vector with an HCMV IE promoter/enhancer provides clear advantages over other previously developed plasmids. Furthermore, expression profile of VEGF121 gene may provide useful information in the design of angiogenic gene therapy in the heart

El factor de crecimiento endotelial vascular (VEGF). Su papel en la fisiopatología peritoneal / No disponible

No disponible

The low efficiency of dendritic cells and macrophages from mice susceptible to Paracoccidioides brasiliensis in inducing a Th1 response

In the present study we evaluated T cell proliferation and Th lymphokine patterns in response to gp43 from Paracoccidioides brasiliensis presented by isolated dendritic cells from susceptible and resistant mice. T cell proliferation assays showed that dendritic cells from susceptible mice were less efficient than those from resistant mice. The pattern of T cell lymphokines stimulated by dendritic cells was always Th1, although the levels of IL-2 and IFN-gamma were lower in T cell cultures from susceptible mice. To determie whether different antigen-presenting cells such as macrophages and dendritic cells stimulated different concentrations of Th1 lymphokines, the production of IFN-gamma and IL-2 was measured. It was observed that dendritic cells were more efficient than macrophages in stimulating lymphoproliferation in resistant mice. However, no significant difference was observed for IFN-gamma or IL-2 production. When cells from susceptible mice were used, macrophages were more efficient in stimulating lymphoproliferation than dendritic cells, but no difference was observed in the production of Th1 cytokine. Taken together, these results suggest the lower efficiency of dendritic cells and macrophages from B10.A mice in stimulating T cells that secrete Th1 lymphokines in vitro, an effect that may be involved in the progression of the disease in vivo

The Relationship between Microvessel Count and the Expression of Vascular Endothelial Growth Factor, p53, and K-ras in Non-Small Cell Lung Cancer

Using immunohistochemical staining, we studied the relationship between the microvessel count (MC) and the expression of K-ras, mutant p53 protein, and vascular endothelial growth factor (VEGF) in 61 surgically resected non-small cell lung cancers (NSCLC) (42 squamous cell carcinoma, 14 adenocarcinoma, 2 large cell carcinoma, 2 adenosquamous carcinoma, and 1 mucoepidermoid carcinoma). MC of the tumors with lymph node (LN) metastasis was significantly higher than that of tumors without LN metastasis (66.1+/-23.1 vs. 33.8+/-13.1, p<0.05). VEGF was positive in 54 patients (88.5%). MC was 58.1+/-25.2 (mean+/-S.D.) in a x200 field, and it was significantly higher in VEGF(+) tumors than in VEGF(-) tumors (61.4+/-23.7 vs. 32.9+/-23.8, p<0.05). VEGF expression was higher in K-ras-positive or mutant p53-positive tumors than in negative tumors (p<0.05). MC was significantly higher in K-ras(+) tumors than in K-ras(-) tumors, although it did not differ according to the level of mutant p53 protein expression. Survival did not differ with VEGF, mutant p53, or K-ras expression, or the level of MC. In conclusion, there is a flow of molecular alterations from K-ras and p53, to VEGF expression, leading to angiogenesis and ultimately lymph node metastasis. Correlations between variables in close approximation and the lack of prognostic significance of individual molecular alterations suggest that tumorigenesis and metastasis are multifactorial processes.

Correlation of VEGF with contrast enhancement on dual-phase dynamic helical CT in liver tumors: preliminary study

The purpose of this preliminary study is to elucidate that vascular endothelial growth factor (VEGF) influences contrast enhancement of hepatic tumors on computed tomography (CT). Fourteen patients with hepatic tumors (11 hepatocellular carcinomas; 3 metastatic cancers) underwent a dual-phase dynamic helical CT or computed tomographic hepatic arteriography. The attenuation of each mass was determined as hyperattenuation, isoattenuation or hypoattenuation with respect to the adjacent nontumorous parenchyma. Gun-needle biopsy was done for each tumor, and paraffin sections were immunostained with anti- VEGF antibody by the avidin-biotin-peroxidase complex method. The pathologic grade was made by intensity (1 +, 2+, 3+) and area (+/-, 1 +, 2+). The tumor ranged 2.0-14.0 cm in size (mean, 5.8 cm). In arterial phase, the intensity was not correlated with the degree of enhancement (p=0.086). However, the correlation between the attenuation value of hepatic arterial phase and the area of positive tumor cells was statistically significant (p=0.002). VEGF may be the factor that enhances the hepatic mass with water-soluble iodinated contrast agent in CT.

The Leukocyte Inhibitory Factor and Circulating Immune Complex in Leprosy Patients

To investigate leukocyte inhibitory factor(LlF) production and circulating immune complexes (CIC) in leprosy, peripheral blood mononuclear cells (PBMC) from 61 patients and sera from 6O patients were tested. The results indicate that there is a defect in LlF production in the lepromatous (LL) or borderline lepromatous (BL) types compared to the tubrculoid (TT) type (mean migration index=66.O +/- 16.O in LL 61.1 +/- 15.3 in BL, 51.9 +/- 11.2 in TT) (p < 0.05). The number of patients with positive CIC was higher among the LL patents (30%) than the TT patients (20%). There was also positive correlation between the bacterial index (Bl) and the CIC level (r=0.46, p < 0.05). The correlation between CIC and LIF in LL patients and the possibility (p=0.06) that the inuease m CIC may account for the decrease in LIF production in LL patients and vice versa are discussed.

Mechanism of immunosuppression in leprosy: presence of suppressor factor(s) from macrophages of lepromatous patients

Human peripheral blood mononuclear cell proliferation induced by Mycobacterium leprae could...