Latest ArticlesIn the past 20 years, tumor immunotherapy has made a significant progress in tumor inhibition effects in both laboratory studies and clinical trails. In the immune response to tumor, effective antitumor immunity is induced during the tumor progress; long-term monitoring of the tumor would be achieved through the immune memory, reducing the possibility of tumor recurrence. In the immune treatment strategies, a focus is delivery of therapeutic immune regulators with nanocarriers. It has been demonstrated that due to the special physical and chemical properties, nanocarriers are easily internalized by immune cells, which regulate the immune responses and effectively induce anti-tumor immune cascade to achieve the tumor inhibition effect. In this paper, we will discuss the progress of nanocarrier-mediated antitumor immunotherapy in recent years.
Traditional Chinese medicinal materials (TCMMs) are the material basis of the traditional Chinese medicines (TCM) in the treatment of disease, and the inherent quality of the TCMMs are of crucial importance for the efficacy and safety of TCM. Most of the TCMMs are originated from the plants with complex chemical compositions, and the chemical diversity is inevitable. How to clarify the relationship between the chemical identity and the biological activity is the key point for quality control of TCMMs in the establishment of the quality standards. The components with great impact on the biological activities should be used as index compounds in the quality evaluation. In this study, based on the results in our previous studies, a research idea on the evaluation of quality difference of TCMMs is proposed. Its application and existing problems are also discussed.
This study was conducted to establish an in vitro 3D liver model and apply it to the drug liver toxicity evaluation. The 3D multicellular sphere model of HepaRG cells was established by hanging-drop technique for evaluation of liver function. The 3D liver model was used to test the hepatotoxicity of isoniazid and amiodarone hydrochloride compared to the 2D cell culture model. Our results showed that HepaRG cells formed a compact spheriod, and the level of cell albumin, urea and the CYP3A4 activity were significantly higher than that of 2D model. With the treatment of amiodarone hydrochloride in 2D and 3D model, the IC50 were 50 and 100 μmol·L-1, respectively. When the dose was less than 1 000 μmol·L-1, isoniazid had no hepatocyte toxicity in 2D model, while the IC50 in 3D model was 700 μmol·L-1. The LDH activities of both drugs in 3D model showed time-and dose-dependent correlation. The results suggest that this in vitro 3D hanging-drop liver model is good for testing liver functions with a high hepatic drug-metabolizing enzyme activity. Compared with the 2D model, the 3D liver model can accurately evaluate the liver toxicity of drugs. Our results demonstrated the importance of in vitro cell culture models for detection of in vivo-relevant adverse effects of drugs.
A series of ursolic acid derivatives were synthesized by the introduction of 4-chloroindole compounds at A ring and esterification and amidation at C-28 position, which structures were characterized by 1H NMR, MS and etc. The cytotoxic activity of derivatives was evaluated against HepG2 and SGC7901 cells in vitro by MTT assay, in which paclitaxel and adriamycin were used as a positive control. The results indicated that all of derivatives can inhibit cell proliferation in HepG2 and SGC7901 cells with a better activity than ursolic acid. Especially, the compounds 6 and 12 showed significant antitumor activity comparable to the paclitaxel. The compounds are worthy to be studied further.
Calcium signaling plays a critical role in response to various abiotic and biotic stresses in plants. Preliminarily evidence showed that calcium signaling perceived and transduced the harmful signaling generated from continuous cropping stress in R. glutinosa. To investigate the roles of calcium signaling in continuous cropping injury formation, the key genes involved in calcium signaling transduction were identified in R. glutinosa transcriptome through bioinformatic methods. Furthermore, the calcium ion concentration in both normal and continuous cropping R. glutinosa root cells were measured by potassium pyroantimonate precipitation and calcium fluorescence method. As a result, a set of 84 calcium signaling-related genes, including 5 CaMs, 12 CBLs, 21 CDPKs, 21 CIPKs, 16 CMLs, and 9 CRKs were captured in R. glutinosa transcriptome. The analysis of expression profile in continuous cropping compared to normal growth R. glutinosa indicated that continuous cropping stress significantly increased the expression of calcium signaling-related genes in continuous cropping R. glutinosa. At the same time, the abundance levels of 12 calcium signaling-related genes quantified by qPCR further validated the high expression of calcium signaling-related genes presented in continous cropping R. glutinosa. In addition, the continuous cropping condition significantly promoted the accumulation of intracellular calcium ions in R. glutinosa based on two methods of potassium pyroantimonate precipitation and calcium fluorescence. This study verified the possible roles of calcium signaling in the formation of continuous cropping injury on molecular and cellular level, which lays a solid foundation for illuminating formation mechanism of continuous cropping injury on molecular level.
The aim of this study is to establish the in vitro methods for the study of induction and inhibition on CYP450 by drugs, and to validate the analytical method and incubation system. A method for the simultaneous determination of eight metabolites of seven subtypes of CYP450 enzymes probe substrates in human liver microsomes (HLM) was established and validated. The incubation system was optimized to confirm the incubation time and protein concentration of HLM, the enzyme activity of seven subtypes of CYP450 enzymes in HLM was determined, and the inhibition effects on each CYP450s were checked by positive controls. The method for the simultaneous determination of three metabolites of subtypes of CYP450 enzymes was established and validated in human primary cultured hepatocytes (HPCH) using the incubation medium. The enzyme activity of three subtypes of CYP450 enzymes in HPCH was determined, and the total RNA was extracted from HPCH after incubation. The expression of CYP450 enzymes were measured by Taqman fluorescence probe method. The induction effects on each CYP450s were examined using the positive controls. The established methods for the determination of metabolites of probe substrates were fully validated, and the results were conformed to the requirements of bioanalytical method validation. The induction and inhibition effects on each CYP450s were checked by positive controls. The established in vitro methods for the study of drug induction and inhibition on CYP450 were simple and reliable, which could be used in the investigation of enzyme induction or inhibition properties of new drug candidates and to evaluation the metabolic interactions of concomitant medication in clinical.
The aim of the experiments is to screen human single-chain variable fragment (scFv) targeting glypican 3 from phage display library, and analyze its biological activity. After several rounds of panning, the binders with high affinity were obtained through phage ELISA and IMGT analysis. The desired scFv gene was then ligated with pET-22b vector yielding recombinant plasmids, which was then introduced into E. coli Rosetta (DE3). Soluble scFv protein was expressed and further purified using Ni2+ affinity chromatography. The purified proteins were identified by SDS-PAGE and Western blot. Subsequently, the affinity and cell based binding activity were measured using Surface Plasmon Resonance (SPR) and flow cytometry assay, separately. Four enriched sequences with relatively high binding affinity were found (1F7, 1D7, 1D4 and 1B10). We also found that 1F7 scFv showed better targeting ability and higher affinity. The scFv could pave the way for new immunotherapies, such as bispecific anitbody, antibody-drug conjugate and chimeric antigen receptor T-cell immunotherapy cell, etc.
Nimodipine is a selective calcium channel antagonist of cerebral vessels smooth muscle and also has polymorphs. It hasn't been reported that different crystal forms influence the metabolism process in huge animals like rhesus monkeys in vivo. This article may provide reference in the control of the quality of nimodipine and quality consistency evaluation. The powder X-ray diffraction (PXRD) method was used to identify different crystal forms and the dissolution test in vitro was used to detect the dissolution. The LC-MS method of assay nimodipine in rhesus monkey plasm was established to determine pharmacokinetics characters of different tablets from different crystal forms in rhesus monkey in vivo. As a result, the tablets inherit difference crystal forms and the dissolution of reference tablets is 1.3% higher than crystal tablets. However, the maximal blood concentration (Cmax) of crystal tablet was 37.3% higher than reference tablet and AUC of crystal tablet was 29.8% higher than reference tablet. After administrated 2.5 mg·kg-1 orally, calculated pharmacokinetics characters were observed as following:Cmax was 381.4 ±327.3 and 178.0 ±214.8 μg·L-1; AUC0-t was 853.1 ±500.7 and 646.5 ±430.3 μg·L-1·h respectively. The serum concentration result of different nimodipine tablets in rhesus monkeys in vivo suggests that polymorphs has a significantly distinction, which points out that controlling the crystal forms of nimodipine is essential to ensure the therapeutic efficacy. It is essential to execute quality consistency evaluation.
The quality of Scutellaria baicalensis Georgi has a close relationship to the harvest time. With the annual and biennial Scutellaria baicalensis Georgi in different harvest periods as samples, we detected the dynamic changes of chemical compositions in their contents by UHPLC-MS/MS metabolomics technology, then identified the biomarkers of different harvest periods and analyzed their changes in content, finally analyzed the correlation among different metabolites. The results showed that chemical compositions of different harvest periods were obviously different, and showed regular changes. According to the results, if the flavonoid aglycones are chosen as the target components, the proposed harvest time could be May. If flavonoid glycosides, the time is from July to August. Plant metabolomics methodology based on UHPLC-MS/MS can be used to detect the chemical compositions of Scutellaria baicalensis Georgi in different harvest periods, which provide a reference to the optimum harvest period of Scutellaria baicalensis Georgi, and also provide a new method of quality evaluation of traditional Chinese medicinal materials.
Interleukin-6 (IL-6)/signal transducers and activators of transcription (STAT) signaling pathway is closely related to the development and progression of atherosclerosis (AS). Taking Chinese natural product berberine (BBR) as the leading compound, a series of novel BBR analogues defined on different types of substituents on position 3 or/and 9 were designed, synthesized and evaluated for their inhibitory activities on phosphorylation of STAT-1 and STAT-3 induced by IL-6. The structure-activity relationship indicated that introduction of rigid fragment on position 3 or 9 was beneficial for enhancing their activities. Among them, compounds 2b and 9 exhibited the most satisfactory potency. The study revealed that the compounds 2b and 9 exhibit anti-inflammatory potencies via activating AMPK, and down-regulation of phosphorylation of STAT1 and STAT3 induced by IL-6 in HUVEC cells. These results suggest that BBR derivatives may inhibit the inflammatory response mediated by the IL-6/STAT signaling pathway through regulation of AMPK, which provides useful insight into the development of BBR derivatives for treatment of atherosclerosis.