2.Single-color Multitarget Flow Cytometry Using Monoclonal Antibodies Labeled with Different Intensities of the Same Fluorochrome.
Annals of Laboratory Medicine 2012;32(3):171-176
BACKGROUND: We developed a single-color multitarget flow cytometry (SM-FC) assay, a single-tube assay with graded mean fluorescence intensities (MFIs). We evaluated the repeatability of SM-FC, and its correlation with multicolor flow cytometry (MFC), to assess its application as a routine FC assay. METHODS: We selected CD19, CD3, CD4, and CD8 as antigen targets to analyze a lymphocyte subset. MFIs were graded by adjusting monoclonal antibody (mAb) volumes to detect several cell populations. Dimly labeled mAb was prepared by decreasing mAb volume and the optimum diluted volume was determined by serial dilution. SM-FC repeatability was analyzed 10 times in 2 normal controls. The correlation between SM-FC and MFC was evaluated in 20 normal and 23 patient samples. RESULTS: CV values (0.8-5.0% and 1.3-4.1% in samples 1 and 2, respectively) acquired by SM-FC with CD3-fluorescein alpha-isothyocyanate (FITC)dim+CD4-FITCbright and with CD19-FITCdim+CD3-FITCbright showed good repeatability, comparable to that acquired by MFC (1.6-3.7% and 1.0-4.8% in samples 1 and 2, respectively). Excellent correlation was observed between the 2 methods in the 20 normal samples (B cells, T cells, non-Thelper cells, and Thelper cells; r2=0.87, 0.97, 0.97, and 0.98, respectively; P<0.05). There were also linear relationships between SM-FC with CD19-FITCdim+CD3-FITCbright and CD8-PEdim+CD4-PEbright, and MFC, in the 23 patient samples (B cells, T cells, Tcytotoxic cells, and Thelper cells; r2> or =0.98, 0.99, 0.99, and 0.99, respectively; P<0.05). CONCLUSIONS: The multicolor, single-tube SM-FC technique is a potential alternative tool for identifying a lymphocyte subset.
Antibodies, Monoclonal/chemistry/*immunology
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Antigens, CD19/chemistry/metabolism
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Antigens, CD3/chemistry/metabolism
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Antigens, CD4/chemistry/metabolism
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Antigens, CD8/chemistry/metabolism
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B-Lymphocyte Subsets/immunology/metabolism
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Color
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Flow Cytometry/*methods
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Fluorescein-5-isothiocyanate/*chemistry
;
Humans
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T-Lymphocyte Subsets/immunology/metabolism
3.Geranyl phenyl ethers from Illicium micranthum and their anti-HBV activity.
Yu LIU ; Yun-Xia YOU ; Li RAO ; Qian HE ; Yu SU ; Yue FAN ; Yi-Zhou LI ; You-Kai XU ; Chuan-Rui ZHANG
Chinese Journal of Natural Medicines (English Ed.) 2022;20(2):139-147
Fourteen new geranyl phenyl ethers (1-14) along with three known compounds (15-17) were isolated from Illicium micranthum, and their structures were elucidated by comprehensive spectroscopic methods. Illimicranins A-H (1-8) were characterized as geranyl vanillin ethers, while 9 and 10 were dimethyl acetal derivatives. Illimicranins I and J (11 and 12) were rare geranyl isoeugenol ethers. Illimicranins K and L (13 and 14) represented the first example of geranyl guaiacylacetone ether and geranyl zingerone ether, respectively. Compounds 1, 2 and 15 exhibited anti-HBV (hepatitis B virus) activity against HBsAg (hepatitis B surface antigen) and HBeAg (hepatitis B e antigen) secretion, and HBV DNA replication.
Antiviral Agents/pharmacology*
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Hepatitis B Surface Antigens
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Hepatitis B e Antigens
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Illicium/chemistry*
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Phenyl Ethers
4.Labeling of CDTPA-dianhydride-coupled CD45 monoclonal antibody with yttrium-90.
Yun-bi FU ; Gui-ping LI ; Fan-yi MENG
Journal of Southern Medical University 2006;26(8):1230-1232
OBJECTIVETo explore the methods for labeling CDTPA-coupled CD45 monoclonal antibody (mAb) with yttrium-90 ((90)Y) for potential acute myeloid therapy.
METHODSCD45 mAb was labeled with (90)Y by CDTPA and the labeling rate, radiochemical purity, final specific activity, and immunological activity of the mAb were detected.
RESULTSWith the optimal molar ratio of CDTPA/Ab at 20:1, the labeling rate was 95%, radiochemical purity 99.8%, and final specific activity 1.9 mCi/mg. This conjugate was stable in vitro with comparable immunological activity in comparison with unlabeled CD45 mAb.
CONCLUSION(90)Y-CDTPA-CD45 mAb possesses good properties as an ideal targetting therapeutic agent for acute leukemia.
Anhydrides ; chemistry ; Antibodies, Monoclonal ; chemistry ; immunology ; Humans ; Immunoconjugates ; chemistry ; immunology ; Isotope Labeling ; methods ; Leukocyte Common Antigens ; immunology ; Pentetic Acid ; chemistry ; Radiopharmaceuticals ; chemical synthesis ; chemistry ; immunology ; Yttrium Radioisotopes ; chemistry
6.Superantigen and class II MHC molecules.
Journal of Korean Medical Science 1995;10(6):393-398
No anstract available.
Animal
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Binding Sites
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Histocompatibility Antigens Class II/chemistry/immunology/*metabolism
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Human
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Superantigens/chemistry/immunology/*metabolism
7.Antibody-drug conjugates: recent advances in conjugation and linker chemistries.
Kyoji TSUCHIKAMA ; Zhiqiang AN
Protein & Cell 2018;9(1):33-46
The antibody-drug conjugate (ADC), a humanized or human monoclonal antibody conjugated with highly cytotoxic small molecules (payloads) through chemical linkers, is a novel therapeutic format and has great potential to make a paradigm shift in cancer chemotherapy. This new antibody-based molecular platform enables selective delivery of a potent cytotoxic payload to target cancer cells, resulting in improved efficacy, reduced systemic toxicity, and preferable pharmacokinetics (PK)/pharmacodynamics (PD) and biodistribution compared to traditional chemotherapy. Boosted by the successes of FDA-approved Adcetris and Kadcyla, this drug class has been rapidly growing along with about 60 ADCs currently in clinical trials. In this article, we briefly review molecular aspects of each component (the antibody, payload, and linker) of ADCs, and then mainly discuss traditional and new technologies of the conjugation and linker chemistries for successful construction of clinically effective ADCs. Current efforts in the conjugation and linker chemistries will provide greater insights into molecular design and strategies for clinically effective ADCs from medicinal chemistry and pharmacology standpoints. The development of site-specific conjugation methodologies for constructing homogeneous ADCs is an especially promising path to improving ADC design, which will open the way for novel cancer therapeutics.
Amino Acids
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metabolism
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Animals
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Antibodies, Monoclonal
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chemistry
;
metabolism
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Antigens
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metabolism
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Genetic Engineering
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Humans
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Immunoconjugates
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chemistry
;
metabolism
8.Crystal structures of the two membrane-proximal Ig-like domains (D3D4) of LILRB1/B2: alternative models for their involvement in peptide-HLA binding.
Gol NAM ; Yi SHI ; Myongchol RYU ; Qihui WANG ; Hao SONG ; Jun LIU ; Jinghua YAN ; Jianxun QI ; George F GAO
Protein & Cell 2013;4(10):761-770
Leukocyte immunoglobulin-like receptors (LILRs), also called CD85s, ILTs, or LIRs, are important mediators of immune activation and tolerance that contain tandem immunoglobulin (Ig)-like folds. There are 11 (in addition to two pseudogenes) LILRs in total, two with two Ig-like domains (D1D2) and the remaining nine with four Ig-like domains (D1D2D3D4). Thus far, the structural features of the D1D2 domains of LILR proteins are well defined, but no structures for the D3D4 domains have been reported. This is a very important field to be studied as it relates to the unknown functions of the D3D4 domains, as well as their relative orientation to the D1D2 domains on the cell surface. Here, we report the crystal structures of the D3D4 domains of both LILRB1 and LILRB2. The two Ig-like domains of both LILRB1-D3D4 and LILRB2-D3D4 are arranged at an acute angle (∼60°) to form a bent structure, resembling the structures of natural killer inhibitory receptors. Based on these two D3D4 domain structures and previously reported D1D2/HLA I complex structures, two alternative models of full-length (four Ig-like domains) LILR molecules bound to HLA I are proposed.
Amino Acid Sequence
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Antigens, CD
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chemistry
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Crystallography, X-Ray
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Histocompatibility Antigens Class I
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chemistry
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Humans
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Immunoglobulins
;
chemistry
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Leukocyte Immunoglobulin-like Receptor B1
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Membrane Glycoproteins
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chemistry
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Models, Molecular
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Peptides
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chemistry
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metabolism
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Protein Binding
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Protein Structure, Tertiary
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Receptors, Immunologic
;
chemistry
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Signal Transduction
9.Two conformations of pHLA-A*2402: a supplement to Wolynes' theory.
Chuansheng LIU ; Yi SHI ; George F GAO
Chinese Journal of Biotechnology 2012;28(11):1370-1377
Wolynes argued that the track of a protein's folding was directed by the tendency of lowering its energy, and thus when a local minimum of its energy was reached, a relatively stable conformation was formed. However not all of the local minimums will lead the protein to a biologically useful conformation, for those otherwise are called energy traps. Wolynes energy landscape theory and natural selection have well explained the high efficiency of protein folding in vivo, instead of being stuck in energy traps. As to whether a protein can assume different conformations with the same bioactivity, there is no clear answer yet. In this paper, two conformational states of a pHLA-A*2402 are discovered after refolding, and by studying their interactions with TCR and CD8alphaalpha, two conformations of pHLA-A*2402 are confirmed of having escaped from natural selection.
CD8 Antigens
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chemistry
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Energy Metabolism
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HLA-A24 Antigen
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chemistry
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Humans
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Protein Conformation
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Protein Folding
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Receptors, Antigen, T-Cell
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chemistry
10.In vivo digestive stability of soybean β-conglycinin β-subunit in WZS minipigs.
Qiong HUANG ; Hai Bin XU ; Zhou YU ; Shan LIU ; Peng GAO
Biomedical and Environmental Sciences 2015;28(1):85-88
By now, the digestive stability experiments provided by most authoritative organizations are in vitro tests. Evaluating the protein digestive stability with in vivo models should be more objective. The present study aimed to verify the in vivo digestibility of soybean β-conglycinin β-subunit in Wuzhishan (WZS) minipigs. Three minipigs were surgically fitted with O-stomach and T-ileum cannulae and fed with soybean meals. According to SDS-PAGE, the 50 kD fraction of soybean β-conglycinin β-subunit persisted in the gastric fluid until 6 h after feeding, which was detected at 3 h and clearly visible at 4-6 h in the intestinal fluid. Western blot with anti-β-conglycinin β-subunit McAb confirmed it.
Animals
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Antigens, Plant
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chemistry
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metabolism
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Digestion
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physiology
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Globulins
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chemistry
;
metabolism
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Male
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Protein Subunits
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chemistry
;
metabolism
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Seed Storage Proteins
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chemistry
;
metabolism
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Soybean Proteins
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chemistry
;
metabolism
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Swine
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Swine, Miniature
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physiology