ABSTRACT
The interactions between the tumor microenvironment and the tumor cells confers a condition that accelerate or decelerate the development of tumor. Of these cells, mesenchymal stem cells (MSCs) have the potential to modulate the tumor cells. MSCs have been established with double functions, whereby contribute to a tumorigenic or anti-tumor setting. Clinical studies have indicated the potential of MSCs to be used as tool in treating the human cancer cells.One of the advantageous features of MSCs that make them as a well-suited tool for cancer therapy is the natural tumor-trophic migration potential. A key specification of the tumor development has been stablished to be angiogenesis. As a result, manipulation of angiogenesis has become an attractive approach for cancer therapy. This review article will seek to clarify the anti-angiogenesis strategy in modulating the MSCs to treat the tumor cells.
ABSTRACT
Mesenchymal stem cells (MSCs) are multipotent stem cells that have multilinear differentiation and self-renewal abilities. These cells are immune-privileged as they express no or low level of class-II major histocompatibility complex (MHC-II) and other costimulatory molecules. Having neuroprotective and regenerative properties, MSCs can be used to ameliorate several intractable neurodegenerative disorders by affecting both innate and adaptive immune systems. Several manipulations like pretreating MSCs with different conditions or agents, and using molecules derived from MSCs or genetically manipulating them, are the common and practical ways that can be used to strengthen MSCs survival and potency. Improved MSCs can have significantly enhanced impacts on diseases compared to MSCs not manipulated. In this review, we describe some of the most important manipulations that have been exerted on MSCs to improve their therapeutic functions and their applications in ameliorating three prevalent neurodegenerative diseases including Alzheimer’s disease, Parkinson’s disease, and Huntington’s disease.
ABSTRACT
Background: Vascular Endothelial Growth Factor [VEGF] is a coordinate regulator of physiological angiogenesis during embryogenesis, skeletal growth and reproductive functions. There are several types of VEGF, including VEGF [165] . VEGFs stimulate endothelial cell growth, angiogenesis, and capillary permeability. Low induction temperature is a major factor for expression of the recombinant VEGF [165] in soluble form. The purpose of this study was cloning and optimization of soluble vascular endothelial growth factor [165] expression in Escherichia coli [E. coli]
Methods: In this study, total RNA of HeLa cell [cervix epithelium] was extracted. The VEGF [165] gene was amplified by reverse transcription polymerase chain reaction [RTPCR], and then VEGF [165] was subcloned into prokaryotic expression vectors pET 32a[+] and transformed into BL21 [DE3] E. coli strain. VEGF [165] expression was optimized by fine adjustments such as induction time and incubation temperature. VEGF [165] was analyzed by DNA sequencing prior to expression and the protein was further characterized by SDS-PAGE and immunoblotting using Hisotag specific polyclonal antibody
Results: Our results demonstrated that VEGF [165] was successfully cloned and expressed in pET-32a[+] vector. Optimization of the expression procedure showed that, induction by 1 mM IPTG at OD600=0.7 and overnight incubation at 22 degree C resulted in the highest expression levels of soluble VEGF [165]
Conclusion: In this study, the expression of VEGF [165] in a high soluble level was successfully cloned and optimized
ABSTRACT
Streptokinase is a potent activator of plasminogen to plasmin, the enzyme that can solubilize the fibrin network in blood clots. Streptokinase is currently used in clinical medicine as a thrombolytic agent. It is naturally secreted by beta-hemolytic streptococci. To reach an efficient method of purification, an immunoaffinity chromatography method was developed that could purify the streptokinase in a single step with high yield. At the first stage, a CNBr-Ac-tivated sepharose 4B-Lysine column was made to purify the human blood plasminogen. The purified plasminogen was utilized to construct a column that could purify the streptokinase. The rabbit was immunized with the purified streptokinase and the anti-streptokinase [IgG] purified on another streptokinase substituted sepharose-4B column. The immunoaffinity column was developed by coupling the purified anti-Streptokinase [IgG] to sepharose 6MB-Protein A. The Escherichia coli [E.coli] BL21 [DE3] pLysS strain was transformed by the recombinant construct [cloned streptokinase gene in pGEX-4T-2 vector] and gene expression was induced by IPTG. The expressed protein was purified by immunoaffinity chromatography in a single step. The immunoaffinity column could purify the recombinant fusion GST-SK to homogeneity. The purity of streptokinase was confirmed by SDS-PAGE as a single band of about 71 kD and its biological activity determined in a specific streptokinase assay. The yield of the purification was about 94%. This method of streptokinase purification is superior to the previous conventional methods.