1.In vitro comparison of thienorphine metabolism in liver microsomes of human, Beagle dog and rat.
Jingting DENG ; Xiaomei ZHUANG ; Hua LI
Acta Pharmaceutica Sinica 2010;45(1):98-103
The inter-species differences of thienorphine metabolism were investigated in human, Beagle dog and rat liver microsomes, by comparing enzyme kinetics of the parent drug and the formation of its major metabolites. The incubation systems of thienorphine with liver microsomes of the three species were optimized in terms of thienorphine concentration, microsomal protein content and incubation time. The concentrations of thienorphine and its metabolites in incubates were measured by a LC-MS/MS method. The biotransformation of thienorphine by human liver microsomes was the lowest among the three species. The K(m), V(max), CL(int) and T1/2 of thienorphine obtained from human liver microsomes were (4.00 +/- 0.59) micromol x L(-1), (0.21 +/- 0.06) micromol x L(-1) x min(-1), (117 +/- 3.19) mL x min(-1) x kg(-1) and (223 +/- 6.10) min, respectively. The corresponding kinetic parameters for dog and rat liver microsomes were (3.57 +/- 0.69) and (3.28 +/- 0.50) micromol x L(-1), (0.18 +/- 0.04) and (0.14 +/- 0.04) micromol x L(-1) x min(-1), (213 +/- 1.06) and (527 +/- 7.79) mL x min(-1) x kg(-1), (244 +/- 1.21) and (70.7 +/- 1.05) min, respectively. A total of six phase I metabolites were observed in liver microsomes, including one N-dealkylated metabolite, three oxidative metabolites and two N-dealkylated oxidation metabolites. All these six metabolites were detected in the liver microsomes of the three species. However, the relative amounts of the metabolites generated were different in three species. The results indicated that the major phase I metabolic pathway of thienorphine was similar in the liver microsomes from all three species. However, the inter-species differences observed were relative amounts of the metabolites as well as the metabolic characteristics of thienorphine in liver microsomal incubates.
2.In vitro comparison of thienorphine metabolism in liver microsomes of human,Beagle dog and rat
Jingting DENG ; Xiaomei ZHUANG ; Hua LI
Acta Pharmaceutica Sinica 2010;0(01):-
The inter-species differences of thienorphine metabolism were investigated in human, Beagle dog and rat liver microsomes, by comparing enzyme kinetics of the parent drug and the formation of its major metabolites. The incubation systems of thienorphine with liver microsomes of the three species were optimized in terms of thienorphine concentration, microsomal protein content and incubation time. The concentrations of thienorphine and its metabolites in incubates were measured by a LC-MS/MS method. The biotransformation of thienorphine by human liver microsomes was the lowest among the three species. The Km, Vmax, CLint and T1/2 of thienorphine obtained from human liver microsomes were (4.00 ? 0.59) ?mol?L-1, (0.21 ? 0.06) ?mol?L-1?min-1, (117 ? 3.19) mL?min-1?kg-1 and (223 ? 6.10) min, respectively. The corresponding kinetic parameters for dog and rat liver microsomes were (3.57 ? 0.69) and (3.28 ? 0.50) ?mol?L-1, (0.18 ? 0.04) and (0.14 ? 0.04) ?mol?L-1?min-1, (213 ? 1.06) and (527 ? 7.79) mL?min-1?kg-1, (244 ? 1.21) and (70.7 ? 1.05) min, respectively. A total of six phase I metabolites were observed in liver microsomes, including one N-dealkylated metabolite, three oxidative metabolites and two N-dealkylated oxidation metabolites. All these six metabolites were detected in the liver microsomes of the three species. However, the relative amounts of the metabolites generated were different in three species. The results indicated that the major phase I metabolic pathway of thienorphine was similar in the liver microsomes from all three species. However, the inter-species differencesobserved were relative amounts of the metabolites as well as the metabolic characteristics of thienorphine in liver microsomal incubates.
3.Metabolism of 3-cyanomethyl-4-methyl-DCK, a new anti-HIV candidate, in human intestinal microsomes.
Xiaomei ZHUANG ; Yuanyuan WEN ; Hua LI ; Jingting DENG ; Weili KONG ; Xingtao TIAN ; Shuli CUI ; Lan XIE
Acta Pharmaceutica Sinica 2010;45(9):1116-22
The biotransformation, CYP reaction phenotyping, the impact of CYP inhibitors and enzyme kinetics of 3-cyanomethyl-4-methyl-DCK (CMDCK), a new anti-HIV preclinical candidate belonging to DCK analogs, were investigated in human intestinal microsomes and recombinant cytochrome P450 (CYP) enzymes. CMDCK (4 micromol L(-1)) was incubated with a panel of rCYP enzymes (CYP1A2, 2C9, 2C19, 2D6 and 3A4) in vitro. The remaining parent drug in incubates was quantitatively analyzed by a LC-MS method. CYP3A4 was identified as the principal CYP isoenzyme responsible for its metabolism in intestinal microsomes. The major metabolic pathway of CMDCK was oxidation and a number of oxidative metabolites were screened with LC-MS. The Km, Vmax, CLint and T1/2 of CMDCK obtained from human intestinal microsome were 45.6 micromol L(-1), 0.33 micromol L(-1) min(-1), 12.1 mL min(-1) kg(-1) and 25.7 min, respectively. Intestinal clearance of CMDCK was estimated from in vitro data to be 3.3 mL min(-1) kg(-1), and was almost equal to the intestinal blood flow rate (4.6 mL min(-1) kg(-1)). The selective CYP3A4 inhibitors, ketoconazole, troleandomycin and ritonavir demonstrated significant inhibitory effects on CMDCK intestinal metabolism, which suggested that co-administration of CMDCK with potent CYP3A inhibitors, such as ritonavir, might decrease its intestinal metabolic clearance and subsequently improve its bioavailability in body.
4.A novel staining protocol based on protein L for detection of expression of chimeric antigen receptor by flow cytometry
Haifeng DENG ; Weidong HAN ; Jingting JIANG
Chinese Journal of Clinical Laboratory Science 2018;36(4):241-244
Objective To evaluate the feasibility of the novel staining protocol based on protein L in flow cytometry to detect the expression of chimeric antigen receptor (CAR) on the surface of T cells from patients.Methods The peripheral blood mononuclear cells(PBMCs) were collected from 2 patients with CD19 + lymphoma by hemapheresis and T cells were purified by magnetic bead selection.CAR was transfected with retroviruses targeting CD19 and CD22 into T cells to induce chimeric antigen receptor-modified T cells (CAR-T cells).The single-chain fragments of antibody molecules on the surface of CAR-T cells were labeled by biotinylated protein L-streptavidin-PE system.The proportions of activated CD19-CAR and CD22-CAR positive T cells in the culture were detected by flow cytometry.The results were compared with those detected by conventional flow cytometry method based on Anti-IgG staining.Results The expression of CAR on the surface of CAR-T cells was successfully detected by flow cytometry protocol based on the staining of single-chain variable fragment (scFv)-biotinylated protein L-streptavidin-PE.The percentages of CD19-CAR-T cells from the 2 patients were 71.6% vs 64.2% and 49.3% vs 43.8% in the protein L group and the Anti-IgG control group respectively,and the percentages of CD22-CAR-T cells were 53.1% vs 46.3% and 56.5% vs 64.0%.The results of the both groups were similar.Conclusion The staining protocol based on protein L could be used as a routine staining method in flow cytometry for the detection of CAR-T cells.
5.Detection of the diagnosis about primary hepatocellular carcinoma with the AFP-IgM immune complexes in serum
Jingting JIANG ; Changping WU ; Jun WU ; Xihu QIN ; Dacheng SUN ; Mei JI ; Bin XU ; Haifeng DENG ; Mingyang LU ; Guoping ZHOU ; Min LI ; Xiao ZHENG ; Jian LIU ; Liangrong SHI ; Xu NING ; Nilssonehle PETER
Chinese Journal of Laboratory Medicine 2008;31(7):789-792
Objective To evaluate the significance of AFP-IgM, this is one of new tumor markers, in the diagnosis of primary hepatocellular carcinoma (PHC). Methods The contents of AFP-IgM and AFP in serum of 103 healthy subjects, 74 patients suffered primary hepatic carcinoma, 27 patients affected by liver cirrhosis and 63 patients affected by chronic hepatitis were detected by means of enzyme linked immunosorbent assay and electrochemiluminescence. No-PHC is comprised of liver cirrhosis,chronic hepatitis and health subjects as control group. Results The area under ROC curve of AFP was larger than that of AFP-IgM (0.85 vs 0.72, Z=3.21) and the best cut-off value of AFP-IgM and AFP was 3×105-AU/L and 10 ug/L respectively, which was determined by ROC curve. Under the cut-off value, the sensitivity of AFP- lgM and AFP for PHC were 64.9% and 79.7%, and the specificity were 75.6% and 80.3%, yet their efficacies were similar. However, for early diagnosis of liver cancer (stage Ⅰ and Ⅱ), the area under ROC curve of AFP-IgM was larger than that of AFP (0.91 vs 0.82,Z=1.73). The sensitivity of AFP-IgM andAFP were 94.4% and 72. 2%, and the specificity were 81.9% and 79.9%. The differences of AFP-IgMand AFP for early diagnosis of liver cancer were statistically significant. When both of the test results combined AFP-IgM with AFP are positive, it can be diagnosed as liver cancer. The specificity of combineddetermination of the two forms was 89.1%, and the efficacy was 79. 0%. Conclusions Both of thesensitivity and specificity of the AFP-IgM test were higher than that of the AFP for early diagnosis of livercancer. We also found that combined determination of the two forms significantly increased the specificityand the positive predictive value for the diagnosis of PHC, thus AFP-IgM was of especially significance forearly diagnosis of liver cancer.