DNA barcoding identification of commercial decoctions in traditional Chinese medicine / 药学学报

Although the guiding principles for molecular identification of traditional Chinese medicines (TCM) using DNA barcoding have been recorded in the Chinese Pharmacopoeia, there is still a lack of systematic research on its application to commercial TCM decoctions. In this study, a total of 212 commercial TCM decoctions derived from different medicinal parts such as root and rhizome, fruit and seed, herb, flower, leaf, cortex, and caulis were collected to verify applicability and accuracy of the method. DNA barcodes were successfully obtained from 75.9% (161/212) of the samples, while other samples failed to be amplified due to genomic DNA degradation. Among the 161 samples, 85.7% of them were identified as recorded species in the Chinese Pharmacopoeia (2020 edition). In addition, 14 samples could be identified as species recorded in the Chinese Pharmacopoeia and their closely related species in the same genus. Morphological identification for the unconfirmed samples showed that eight were genuine species and three were adulterants, while the other three were unidentifiable due to lack of morphological characteristics. Furthermore, the DNA barcodes of seven samples accurately mapped to the sequences of adulterants. Remarkably, counterfeit products were detected in two samples. These results demonstrate that DNA barcoding is suitable for the identification of commercial TCM decoctions. The method can effectively detect adulterants and is appropriate for use throughout the industrial chain of TCM production and distribution, and by the supervisory agencies as well.

High-level expression, purification and characterization of codon-optimized recombinant hemagglutinin 5 proteins in mammalian cells / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Numerous Asian cases of avian influenza virus infection, especially the highly pathogenic strain H5N1, in humans have raised the concern that another influenza pandemic is close. However, there are no effective therapeutic drugs or preventative vaccines available. Hemagglutinin is the membrane glycoprotein of avian influenza virus responsible for receptor binding to human cells and the main immunogenic protein that elicits a strong immune response. Although this protein is of great importance to the study of pathogenesis and vaccine development, its expression and purification are difficult due to high levels of glycosylation.</p><p><b>METHODS</b>In this study, we expressed codon-optimized, full-length hemagglutinin 5 (H5) protein fused with a human IgG Fc tag (H5-Fc) in HEK293 cells. To enhance secretion of this protein, we also deleted the transmembrane domain and the intracellular domain of the H5 protein (H5DeltaTM-Fc). Purified proteins were obtained using a protein A column.</p><p><b>RESULTS</b>ELISA revealed that the yield of soluble H5DeltaTM-Fc protein in the supernatant was about 20 mg/L. Western blotting and fluorescence activated cell sorter (FACS) indicated that the purified H5 protein was correctly folded and biologically active.</p><p><b>CONCLUSION</b>Purification of H5 proteins from mammalian cells could be used for large-scale production of recombinant H5 protein for basic scientific research or the development of vaccines.</p>

Establishment of high-throughput drug screening model targeting retinoic acid receptor in cells / 药学学报

<p><b>AIM</b>To screen new drug for the treatment of acute promyelocytic leukemia, psoriasis and acne, high-throughput drug screening cell models marked by green fluorescent protein (GFP) have been established.</p><p><b>METHODS</b>Eight repeats of retinoic acid response element (RARE) were synthesized and cloned into a GFP expression vector. This construct was stably transfected into cells in vitro. Stable and sensitive cell clones with high copy numbers of RARE were selected by retinoic acid (RA) using fluorescence-activated cell sorting (FACS).</p><p><b>RESULTS</b>A cell line has been chosen to be high-throughput drug screening cell model. This model was shown with low background, high sensitive and good reproducibility, and was convenient and inexpensive.</p><p><b>CONCLUSION</b>This drug screening cell model can be used for retinoic acid receptor target high-throughput drug screening.</p>