To investigate the effect of the anti-endotoxic part of Radix Isatidis on the expression of moesin mRNA in murine tissues induced by lipopolysaccharide （LPS）, the sample solution of F0z2 part from Radix Isatidis was...To investigate the effect of the anti-endotoxic part of Radix Isatidis on the expression of moesin mRNA in murine tissues induced by lipopolysaccharide （LPS）, the sample solution of F0z2 part from Radix Isatidis was intrapefitoneally administered to experimental mice, and the lipopolysaccharide （LPS） were injected into the tail vein, and then the tissues of liver, kidney and spleen were colleted and cut into slices. The mRNA was detected by moesin mRNA hybridization in situ. The staining results were observed under microscope. It was found that moesin mRNA expression was increased in the tissues of liver, kidndy and spleen in mice treated with LPS, while in the mice pre-treated with F022 part from Radix Isatidis, the LPS-induced moesin mRNA expressions in these tissues were inhibited in a dose-dependant manner. Our study showed that F022 part from Radix Isatidis can inhibit the LPS-induced expression of moesin mRNA in the tissues of liver, kidney and spleen in mice.展开更多
Endotoxins(also known as lipopolysaccharides(LPS)) are undesirable by-products of recombinant proteins,purified from Escherichia coli.LPS can be considered stable under a wide range of temperature and pH,making their ...Endotoxins(also known as lipopolysaccharides(LPS)) are undesirable by-products of recombinant proteins,purified from Escherichia coli.LPS can be considered stable under a wide range of temperature and pH,making their removal one of the most difficult tasks in downstream processes during protein purification.The inherent toxicity of LPS makes their removal an important step for the application of these proteins in several biological assays and for a safe parenteral administration.Immobilized metal affinity chromatography(IMAC) enables the affinity interactions between the metal ions(immobilized on the support through the chelating compound) and the target molecules,thus enabling high-efficiency separation of the target molecules from other components present in a mixture.Affinity chromatography is applied with Ca2+-iminodiacetic acid(IDA) to remove most of the LPS contaminants from the end product(more than90%).In this study,the adsorption of LPS on an IDA-Ca2+ was investigated.The adsorption Freundlich isotherm of LPS-IDA-Ca2+ provides a theoretical basis for LPS removal.It was found that LPS is bound mainly by interactions between the phosphate group in LPS and Ca2+ ligands on the beads.The factors such as pH(4.0 or 5.5) and ionic strength(1.0 mol/L) are essential to obtain effective removal of LPS for contaminant levels between endotoxin' concentration values less than100 EU/mL and 100 000 EU/mL.This new protocol represents a substantial advantage in time,effort,and production costs.展开更多
基金This project was supported by grants from National Natural Sciences Foundation (No. 39870872 and No. 39170877)a grant from the Ministry of Health of China (No. 982110)
文摘To investigate the effect of the anti-endotoxic part of Radix Isatidis on the expression of moesin mRNA in murine tissues induced by lipopolysaccharide （LPS）, the sample solution of F0z2 part from Radix Isatidis was intrapefitoneally administered to experimental mice, and the lipopolysaccharide （LPS） were injected into the tail vein, and then the tissues of liver, kidney and spleen were colleted and cut into slices. The mRNA was detected by moesin mRNA hybridization in situ. The staining results were observed under microscope. It was found that moesin mRNA expression was increased in the tissues of liver, kidndy and spleen in mice treated with LPS, while in the mice pre-treated with F022 part from Radix Isatidis, the LPS-induced moesin mRNA expressions in these tissues were inhibited in a dose-dependant manner. Our study showed that F022 part from Radix Isatidis can inhibit the LPS-induced expression of moesin mRNA in the tissues of liver, kidney and spleen in mice.
基金supported by grants from the Brazilian Agency Coordination of Graduate Level Training(CAPES,project 0366/09-9)State of So Paulo Research Support Foundation(FAPESP-Brazil,project 2005/60159-7)
文摘Endotoxins(also known as lipopolysaccharides(LPS)) are undesirable by-products of recombinant proteins,purified from Escherichia coli.LPS can be considered stable under a wide range of temperature and pH,making their removal one of the most difficult tasks in downstream processes during protein purification.The inherent toxicity of LPS makes their removal an important step for the application of these proteins in several biological assays and for a safe parenteral administration.Immobilized metal affinity chromatography(IMAC) enables the affinity interactions between the metal ions(immobilized on the support through the chelating compound) and the target molecules,thus enabling high-efficiency separation of the target molecules from other components present in a mixture.Affinity chromatography is applied with Ca2+-iminodiacetic acid(IDA) to remove most of the LPS contaminants from the end product(more than90%).In this study,the adsorption of LPS on an IDA-Ca2+ was investigated.The adsorption Freundlich isotherm of LPS-IDA-Ca2+ provides a theoretical basis for LPS removal.It was found that LPS is bound mainly by interactions between the phosphate group in LPS and Ca2+ ligands on the beads.The factors such as pH(4.0 or 5.5) and ionic strength(1.0 mol/L) are essential to obtain effective removal of LPS for contaminant levels between endotoxin' concentration values less than100 EU/mL and 100 000 EU/mL.This new protocol represents a substantial advantage in time,effort,and production costs.
