The pharmacokinetic and pharmacodynamic properties of site-specific pegylated genetically modified recombinant human interleukin-11 in normal and thrombocytopenic monkeys.

In order to improve the pharmacokinetic and pharmacodynamic properties of recombinant human interleukin-11 mutein (mIL-11) and to reduce the frequency of administration, we examined the feasibility of chemical modification of mIL-11 by methoxy polyethylene glycol succinimidyl carbonate (mPEG-SC). PEG-mIL-11 was prepared by a pH controlled amine specific method. Bioactivity of the protein was determined in a IL-11-dependent in vitro bioassay, its pharmacodynamic and pharmacokinetic properties were investigated by using normal and thrombocytopenic monkey models. N-terminus sequencing and peptide mapping analysis revealed that Lys33 is the PEGylated position for PEG-mIL-11. Bioactivity of PEG-mIL-11 assessed by B9-11 cell proliferation assay was comparable to that of mIL-11. More than 79-fold increase in area-under-the curve (AUC) and 26-fold increase in maximum plasma concentration (Cmax) was observed in pharmacokinetic analysis. Single dose administration of the PEG-mIL-11 induced blood platelets number increase and the effect duration were comparable to that of 7 to 10 consecutive daily administration of mIL-11 to the normal and thrombocytopenic monkey models. PEG-mIL-11 is a promising therapeutic for thrombocytopenia.

Production and characterization of highly purified recombinant thymosin beta 4 in Escherichia coli.

Thymosin ß4 (Tß4) is a small peptide composed of 43 amino acids. It has many important biological functions, such as promoting cardiac repair and wound healing, and therefore has great potential in clinical applications. In this report, we describe a novel and efficient way to produce highly purified and active Tß4. It was expressed in a soluble form using a DsbA and hexahistindine tag in Escherichia coli (E. coli). Using high cell density cultivation, the final biomass concentration was about 50 g L(-1) dry cell weight with the expression level of the fusion protein being 40%. To obtain highly purified protein, a purification process involving a five-step column procedure was implemented. The purity of Tß4 was above 98% and all the host cell related impurities, such as endotoxin, host cell protein and residual DNA levels, were within the permissible range listed in the Chinese Pharmacopoeia. The E-rosette test demonstrated that the bioactivity of purified Tß4 was consistent with other published work. This is the first report producing highly purified Tß4 from genetically engineered sources.

[ISSR-PCR analysis in different species and populations of Rhizoma Curcumae].

OBJECTIVE: To study the genetic diversity and genetic relationship in different species and populations of Curcuma by ISSR-PCR marker technique. METHOD: Eighty populations and 37 samples of Curcuma including C. phaeocaulis, C. kwangsiensis and C. wenyujin were studied by ISSR-PCR markers. The systematic diagram of Similar coefficient and genetic distance were set up by POPGEN32 software and clustered by UPGMA method. RESULT: A total of 65 loci were scored by 5 primers, among which 34 were polymorphic loci. The percentage of polymorphic loci was 52.3%. Genetic similarity coefficient changed from 0.6864 to 0.9997. Nei's gene diversity index (H), and Shannon information index (I) were 0.1521 and 0.2338. The inner genetic diversity of Curcuma species was lower than the outer. CONCLUSION: The genetic variation of different populations Curcuma was big. The inherited differentiation of inner populations was low. Different populations of Curcuma were related to character of species and geological distribution.