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1.
J Am Chem Soc ; 143(27): 10157-10167, 2021 07 14.
Article in English | MEDLINE | ID: mdl-34189908

ABSTRACT

Glycosylation is a major modification of secreted and cell surface proteins, and the resultant glycans show considerable heterogeneity in their structures. To understand the biological processes arising from each glycoform, the preparation of homogeneous glycoproteins is essential for extensive biological experiments. To establish a more robust and rapid synthetic route for the synthesis of homogeneous glycoproteins, we studied several key reactions based on amino thioacids. We found that diacyl disulfide coupling (DDC) formed with glycosyl asparagine thioacid and peptide thioacid yielded glycopeptides. This efficient coupling reaction enabled us to develop a new glycoprotein synthesis method, such as the bifunctional thioacid-mediated strategy, which can couple two peptides with the N- and C-termini of glycosyl asparagine thioacid. Previous glycoprotein synthesis methods required valuable glycosyl asparagine in the early stage and subsequent multiple glycoprotein synthesis routes, whereas the developed concept can generate glycoproteins within a few steps from peptide and glycosyl asparagine thioacid. Herein, we report the characterization of the DDC of amino thioacids and the efficient ability of glycosyl asparagine thioacid to be used for robust glycoprotein semisynthesis.


Subject(s)
Asparagine/analogs & derivatives , Cytokines/chemical synthesis , Glycoproteins/chemical synthesis , Sulfhydryl Compounds/chemistry , Escherichia coli/chemistry , Escherichia coli/metabolism , Glycopeptides/chemistry , Glycosylation , Models, Molecular , Peptides/chemistry , Peptides/metabolism , Protein Conformation , Sulfides
2.
Org Biomol Chem ; 17(48): 10148-10152, 2019 12 28.
Article in English | MEDLINE | ID: mdl-31710063

ABSTRACT

The linear synthesis of the N-terminal domain of mISG15 has been developed which enables the synthesis of full-length mISG15 and the activity-based probe Rho-mISG15-PA via native chemical ligation. Pilot experiments showed that the synthetic proteins were properly folded and recognized by endogenous enzymes. Our synthesis strategy allows the generation of other mISG15-based probes and reagents that can accelerate the research in this field.


Subject(s)
Cytokines/chemical synthesis , Cytokines/metabolism , Solid-Phase Synthesis Techniques/methods , Amino Acid Sequence , Fluorescent Dyes/chemistry , Interleukins/metabolism , Ligands , Molecular Weight , Protein Binding , Protein Domains , Rhodamines/chemistry , Structure-Activity Relationship , Ubiquitins/chemical synthesis , Ubiquitins/metabolism
3.
Nature ; 574(7776): 63-68, 2019 10.
Article in English | MEDLINE | ID: mdl-31554967

ABSTRACT

The gp130 receptor cytokines IL-6 and CNTF improve metabolic homeostasis but have limited therapeutic use for the treatment of type 2 diabetes. Accordingly, we engineered the gp130 ligand IC7Fc, in which one gp130-binding site is removed from IL-6 and replaced with the LIF-receptor-binding site from CNTF, fused with the Fc domain of immunoglobulin G, creating a cytokine with CNTF-like, but IL-6-receptor-dependent, signalling. Here we show that IC7Fc improves glucose tolerance and hyperglycaemia and prevents weight gain and liver steatosis in mice. In addition, IC7Fc either increases, or prevents the loss of, skeletal muscle mass by activation of the transcriptional regulator YAP1. In human-cell-based assays, and in non-human primates, IC7Fc treatment results in no signs of inflammation or immunogenicity. Thus, IC7Fc is a realistic next-generation biological agent for the treatment of type 2 diabetes and muscle atrophy, disorders that are currently pandemic.


Subject(s)
Cytokine Receptor gp130/metabolism , Cytokines/chemical synthesis , Cytokines/therapeutic use , Diabetes Mellitus, Type 2/drug therapy , Immunoglobulin G/therapeutic use , Recombinant Fusion Proteins/therapeutic use , Adaptor Proteins, Signal Transducing/metabolism , Animals , Binding, Competitive , Cytokines/chemistry , Diabetes Mellitus, Type 2/metabolism , Drug Design , Fatty Liver/prevention & control , Glucose Tolerance Test , Humans , Hyperglycemia/drug therapy , Hyperglycemia/metabolism , Incretins/metabolism , Interleukin-6/antagonists & inhibitors , Interleukin-6/metabolism , Male , Mice , Muscle, Skeletal/drug effects , Obesity/metabolism , Pancreas/metabolism , Phosphoproteins/metabolism , Protein Engineering , Receptors, Interleukin-6/metabolism , Signal Transduction , Transcription Factors , Weight Gain/drug effects , YAP-Signaling Proteins
4.
Med. clín (Ed. impr.) ; 151(4): 148-155, ago. 2018. ilus, tab, graf
Article in Spanish | IBECS | ID: ibc-173867

ABSTRACT

Las interacciones farmacológicas de los agentes biológicos no son bien conocidas. Debido a que los fármacos biológicos no son metabolizados por las enzimas del citocromo P450 (CYP450) ni interaccionan con los transportadores transmembrana, existe la percepción de que estos no presentan interacciones medicamentosas con los fármacos de síntesis química. Sin embargo, el aclaramiento de los agentes biológicos puede variar en función de la respuesta inmune o si se modifica la expresión de sus células diana, lo cual puede ocurrir por la acción de muchos agentes químicos. Además, algunos biológicos son capaces de modular la expresión de las enzimas del sistema CYP450. En esta revisión, se proporciona una descripción de las propiedades farmacocinéticas y posibles interacciones de los fármacos biológicos, centrándonos en los anticuerpos monoclonales, y como estos pueden interaccionar con las moléculas de síntesis química. Creemos que su conocimiento es importante para los clínicos y afecta a varias especialidades médicas


The pharmacological interactions of biological agents are not well known. Because biologic agents are not metabolised by cytochrome P450 (CYP) enzymes and do not interact with cell membrane transporters, it is generally perceived that they are free from interactions with small molecule drugs. However, the clearance of biological agents varies depending on the modulation of the immune response or by either increasing or reducing the expression of target cells of the biological agents, which can occur through the action of multiple synthetic chemical agents. Furthermore, some biological agents may modify the metabolism of chemical drugs through their effects on the expression of P450 system enzymes.. In this review, we will provide an outline of the pharmacokinetics properties and pharmacologic interactions of biological drugs, focusing on monoclonal antibodies, and how these can interact with chemical synthesis molecules. We believe knowledge of them is important for clinicians and affects multiple clinical specialties


Subject(s)
Humans , Antibodies, Monoclonal/pharmacokinetics , Antibodies, Monoclonal/adverse effects , Drug Interactions/physiology , Biological Factors , Cytokines/chemical synthesis
5.
Eur J Med Chem ; 144: 318-329, 2018 Jan 20.
Article in English | MEDLINE | ID: mdl-29275231

ABSTRACT

A new series of blood-brain barrier permeable molecules designed to mimic the activity of Pleiotrophin in the CNS has been designed and synthesized. These compounds exert their action by interacting with the intracellular domain PD1 of the Protein Tyrosine-Phosphatase Receptor Z1 (PTPRZ1), and inhibiting its tyrosine phosphatase activity. The most potent compounds 10a and 12b (IC50 = 0,1 µM) significantly increase the phosphorylation of key tyrosine residues of PTPRZ1 substrates involved in neuronal survival and differentiation, and display protective effects against amphetamine-induced toxicity. Docking and molecular dynamics experiments have been used to analyze the binding mode and to explain the observed selectivity against PTP1B. An In vivo experiment has demonstrated that 10a can cross the BBB, thus promoting the possibility of moving forward these candidates for the development of drugs for the treatment of CNS disorders, such as drug addiction and neurodegenerative diseases.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Carrier Proteins/pharmacology , Central Nervous System Diseases/drug therapy , Cytokines/pharmacology , Enzyme Inhibitors/pharmacology , Receptor-Like Protein Tyrosine Phosphatases, Class 5/antagonists & inhibitors , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemical synthesis , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Blood-Brain Barrier/drug effects , Blood-Brain Barrier/metabolism , Carrier Proteins/chemical synthesis , Carrier Proteins/chemistry , Cell Line , Cell Survival/drug effects , Central Nervous System Diseases/metabolism , Cytokines/chemical synthesis , Cytokines/chemistry , Dose-Response Relationship, Drug , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Humans , Mice , Models, Molecular , Molecular Structure , Rats , Receptor-Like Protein Tyrosine Phosphatases, Class 5/metabolism , Structure-Activity Relationship
6.
Salvador; s.n; 2015. 83 p. ilus, tab.
Thesis in Portuguese | LILACS | ID: biblio-1000982

ABSTRACT

INTRODUÇÃO: O vírus linfotrópico das células T humano tipo 1 (HTLV-1) é endêmico na Bahia e está associado com doenças graves, como a Paraparesia Espástica Tropical/Mielopatia associada ao HTLV-1 (HAM/TSP) e a Dermatite Infecciosa associada ao HTLV-1 (DIH). Escassos trabalhos tem sido reportados com a avaliação de citocinas e quimiocinas em indivíduos jovens infectados pelo HTLV-1 e não existem dados sobre a manifestação simultânea DIH e HAM/TSP na faixa infanto-juvenil. OBJETIVO: Avaliar as concentrações plasmáticas de citocinas e quimiocinas na infecção pelo HTLV-1 em indivíduos infanto-juvenis. MÉTODO: Foram incluídos 61 indivíduos portadores do HTLV-1 distribuídos nos grupos Portadores assintomáticos, pacientes com a DIH, pacientes com DIH/HAM/TSP, pacientes com a HAM/TSP e 20 indivíduos saudáveis sem a infecção pelo HTLV-1, todos na faixa infanto-juvenil. As concentrações plasmáticas foram comparadas através do método de Elisa e de Cytometric Bead Array (CBA)...


INTRODUCTION: The lymphotropic virus of cells T human type 1 (HTLV ) is endemic in Bahia and it is associated with serious diseases such as Tropical Spastic Paraparesis/associated myelopathy with HTLV-1 and Infectious Dermatitis associated with HTLV -1 (IDH). Very little work has been reported with the evaluation of cytokines and chemokines in the IDH and there has been no data on the manifestation simultaneous IDH and HAM/TSP in children and youth range. OBJECTIVE: To evaluate the plasma concentrations of cytokines and chemokines in HTLV-1 infection in children and young individuals. METHOD: We included 61 individuals HTLV-1 spread in groups Asymptomatic Carriers, patients with IDH, patients with IDH/HAM/TSP, patients with HAM/TSP and 20 healthy individuals without HTLV-1, all in children's range. Plasma concentrations were compared using the ELISA method and Cytometric Bead Array (CBA)...


Subject(s)
Humans , Cytokines/analysis , Cytokines/adverse effects , Cytokines/immunology , Cytokines/blood , Cytokines/chemical synthesis , Cytokines/ultrastructure , Lymphocytes , Lymphocytes/pathology , Human T-lymphotropic virus 1/isolation & purification , Human T-lymphotropic virus 1/pathogenicity
7.
Dev Comp Immunol ; 39(3): 147-53, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23178406

ABSTRACT

Insect cytokine paralytic peptide (PP) upregulates the expression of immune-related genes and contributes to host defense in the silkworm Bombyx mori. The present findings demonstrated that PP promotes nitric oxide (NO) production and induces the expression of NO synthase. A pharmacologic NO synthase inhibitor suppressed the PP-dependent (i) induction of immune-related genes, (ii) activation of p38 mitogen-activated protein kinase, and (iii) killing delay of silkworm larvae by Staphylococcus aureus. The upstream mechanism of NO synthesis in insect immunity has been unknown, and the present results suggest for the first time that an insect cytokine induces NO and contributes to self-defense.


Subject(s)
Bombyx/immunology , Cytokines/immunology , Insect Proteins/metabolism , Neuropeptides/immunology , Nitric Oxide Synthase/metabolism , Nitric Oxide/metabolism , Staphylococcus aureus/immunology , Animals , Apoptosis/drug effects , Bombyx/microbiology , Cells, Cultured , Cytokines/chemical synthesis , Immunity, Innate/drug effects , Insect Proteins/genetics , Muscle Contraction/drug effects , NG-Nitroarginine Methyl Ester/pharmacology , Neuropeptides/administration & dosage , Neuropeptides/chemical synthesis , Nitric Oxide Synthase/antagonists & inhibitors , Nitric Oxide Synthase/genetics , Paralysis/etiology , Paralysis/prevention & control , Signal Transduction/drug effects , Up-Regulation/drug effects , p38 Mitogen-Activated Protein Kinases/metabolism
8.
Belo Horizonte; s.n; 2011. xviii,89 p. ilus.
Thesis in Portuguese | LILACS | ID: lil-658755

ABSTRACT

Neste trabalho, o perfil fenotípico e de síntese de citocinas pró-inflamatórias (IFN-, TNF- e IL-12) e reguladoras (IL-4, IL-5 e IL-10) em células da imunidade inata (neutrófilos, monócitos e células NK) e adaptativa (linfócitos CD4+, linfócitos CD8+ e linfócitos CD19+) do sangue periférico de indivíduos primo e/ou revacinados com a vacina antiamarílica 17DD, bem como um caso de reação adversa à vacinação foram investigados por citometria de fluxo após cultura rápida in vitro na ausência e presença da estimulação antígeno-específica. Foram avaliados 10 adultos saudáveis, com idade entre 21 e 51 anos, em 4 tempos distintos: antes da vacinação, 7, 15 e 30 dias após primovacinação. Após cultura in vitro foi observado um perfil global de citocinas pró-inflamatórias, transiente no 7° dia, principalmente devido às células da imunidade inata, seguido por perfil misto de citocinas inflamatórias e reguladoras nos 15° e 30° dias após a vacinação antiamarílica 17DD. Em um 2º estudo, foi observada uma resposta imune adaptativa robusta, acompanhada por anormalidades na resposta do sistema imune inato em um caso de evento adverso grave, seguido à vacinação 17D.


Em adição, em um 3º estudo, foram incluídas 60 crianças com idade entre 9 e 47 meses, um ano após a primo e/ou revacinação antiamarílica 17DD, classificadas de acordo com os níveis de anticorpos neutralizantes antiamarílicos apresentados após a vacinação em: respondedoras (médios ou altos títulos de anticorpos neutralizantes), não respondedoras, respondedoras após revacinação e um grupo de crianças não vacinadas. Os dados da avaliação do impacto dos antígenos vacinais 17DD no perfil das citocinas dos leucócitos periféricos destas crianças demonstraram que, na presença de títulos médios de anticorpos neutralizantes após a primovacinação, o estímulo por antígenos vacinais 17DD in vitro foi capaz de induzir um perfil balanceado de citocinas pró-inflamatórias e reguladoras, envolvendo células da imunidade inata e adaptativa, enquanto que uma assinatura polarizada reguladora foi observada no grupo de crianças primovacinadas não respondedoras e uma assinatura proeminente pró-inflamatória no grupo de crianças que apresentaram títulos altos de anticorpos neutralizantes após a primovacinação. Em conjunto os dados sugerem que uma resposta imune predominantemente do tipo balanceada, com síntese de citocinas pró-inflamatórias e reguladoras, envolvendo tanto células da imunidade inata quanto da imunidade adaptativa parece ser essencial para a indução de uma resposta imune efetiva e segura após a vacinação antiamarílica


Subject(s)
Humans , Male , Female , Child , Adult , Cytokines/chemical synthesis , Flow Cytometry/methods , Yellow Fever/immunology , Yellow Fever Vaccine/analysis
9.
Belo Horizonte; s.n; 2011. xviii,89 p. ilus.
Thesis in Portuguese | LILACS, Coleciona SUS | ID: biblio-937909

ABSTRACT

Neste trabalho, o perfil fenotípico e de síntese de citocinas pró-inflamatórias (IFN-, TNF- e IL-12) e reguladoras (IL-4, IL-5 e IL-10) em células da imunidade inata (neutrófilos, monócitos e células NK) e adaptativa (linfócitos CD4+, linfócitos CD8+ e linfócitos CD19+) do sangue periférico de indivíduos primo e/ou revacinados com a vacina antiamarílica 17DD, bem como um caso de reação adversa à vacinação foram investigados por citometria de fluxo após cultura rápida in vitro na ausência e presença da estimulação antígeno-específica. Foram avaliados 10 adultos saudáveis, com idade entre 21 e 51 anos, em 4 tempos distintos: antes da vacinação, 7, 15 e 30 dias após primovacinação. Após cultura in vitro foi observado um perfil global de citocinas pró-inflamatórias, transiente no 7° dia, principalmente devido às células da imunidade inata, seguido por perfil misto de citocinas inflamatórias e reguladoras nos 15° e 30° dias após a vacinação antiamarílica 17DD. Em um 2º estudo, foi observada uma resposta imune adaptativa robusta, acompanhada por anormalidades na resposta do sistema imune inato em um caso de evento adverso grave, seguido à vacinação 17D.


Em adição, em um 3º estudo, foram incluídas 60 crianças com idade entre 9 e 47 meses, um ano após a primo e/ou revacinação antiamarílica 17DD, classificadas de acordo com os níveis de anticorpos neutralizantes antiamarílicos apresentados após a vacinação em: respondedoras (médios ou altos títulos de anticorpos neutralizantes), não respondedoras, respondedoras após revacinação e um grupo de crianças não vacinadas. Os dados da avaliação do impacto dos antígenos vacinais 17DD no perfil das citocinas dos leucócitos periféricos destas crianças demonstraram que, na presença de títulos médios de anticorpos neutralizantes após a primovacinação, o estímulo por antígenos vacinais 17DD in vitro foi capaz de induzir um perfil balanceado de citocinas pró-inflamatórias e reguladoras, envolvendo células da imunidade inata e adaptativa, enquanto que uma assinatura polarizada reguladora foi observada no grupo de crianças primovacinadas não respondedoras e uma assinatura proeminente pró-inflamatória no grupo de crianças que apresentaram títulos altos de anticorpos neutralizantes após a primovacinação. Em conjunto os dados sugerem que uma resposta imune predominantemente do tipo balanceada, com síntese de citocinas pró-inflamatórias e reguladoras, envolvendo tanto células da imunidade inata quanto da imunidade adaptativa parece ser essencial para a indução de uma resposta imune efetiva e segura após a vacinação antiamarílica


Subject(s)
Male , Female , Humans , Child , Adult , Cytokines/chemical synthesis , Flow Cytometry/methods , Yellow Fever Vaccine/analysis , Yellow Fever/immunology
10.
Clín. investig. arterioscler. (Ed. impr.) ; 20(6): 233-238, nov. 2008. ilus, tab
Article in Es | IBECS | ID: ibc-70129

ABSTRACT

Introducción. Además de sus acciones fisiológicas en el ámbito renal en el equilibrio hidroelectrolítico, la aldosterona está implicada en algunas alteraciones cardiovasculares asociadas a la hipertensión arterial, como la hipertrofia ventricular, la fibrosis cardíaca, la insuficiencia cardíaca, etc. El objetivo del estudio fue evaluar el posible papel de los mineral ocorticoides en el proceso inflamatorio vascular asociado a la hipertensión en ratas. Métodos. Se utilizaron ratas macho espontáneamente hipertensas (SHR, del inglés spontaneously hypertensive rats) de 18 semanas de edad, tratadas con 2 dosis del antagonista del receptor de mineralocorticoides eplerenona, de 30y 100 mg/kg/día, durante 10 semanas. Se utilizó un grupo de SHR sin tratar como control, y un grupo de ratas Wistar Kyoto (WKY) se utilizó como grupo de referencia normotenso. Se valoró la presión arterial sistólica (PAS), las concentraciones plasmáticas de interleucina (IL) 1B e IL-6, así como la expresión aórtica del ácido ribonucleicomensajero (ARNm) de ambas, del factor de necrosis tumoral alfa (TNF-alfa), del factor de transcripción nuclear kB (NF-kB), valorando elp105 (precursor de la subunidad p50 del NF-kB) yde su inhibidor (IkB).Resultados. Las ratas SHR presentaron valores superiores de PAS respecto a las ratas WKY (p <0,05). Los valores plasmáticos de IL-1Beta e IL-6, así como su expresión génica y la del TNF-alfa, aumentaron en las SHR (p < 0,05). Asimismo, las SHR presentaron un aumento en la expresión génica del NF-kB y una disminución del IkB. Solamente el tratamiento con eplerenona 100mg/kg/día redujo significativamente los valores de PAS. Sin embargo, ambas dosis redujeron los valores plasmáticos y la expresión génica aórtica de las citocinas valoradas (p < 0,05). Asimismo, ambas dosis redujeron la expresión aórtica del (..) (AU)


Introduction. Besides its physiological role in the control of hydroelectrolyte balance at renal level, aldosterone plays an important role incardiovascular alterations associated with hypertension, such as left ventricular hypertrophy, cardiac fibrosis, congestive heart failure, etc. Th eaim of the present study was to evaluate the effect of endogenous mineral corticoids on vascular inflammation associated with hypertension in rats. Methods. Male spontaneously hypertensive rats(SHR) (18 weeks old) were treated with two doses of eplerenone (30 and 100 mg/kg/day) for 10 weeks. A group of (n = 8) untreated SHR was used as a control-vehicle group, and a group of Wistar Kyotorats (n=8) was used as a reference of (..) (AU)


Subject(s)
Animals , Rats , Mineralocorticoids/adverse effects , Mineralocorticoids/blood , Mineralocorticoids/toxicity , Hypertension/complications , Hypertension/therapy , Myocardial Infarction/epidemiology , Cytokines/analysis , Cytokines/chemical synthesis , Tumor Necrosis Factor-alpha/chemical synthesis , Tumor Necrosis Factor-alpha/pharmacology , Heart Diseases/complications , Heart Diseases/etiology , Aldosterone/analysis , Aldosterone/toxicity , Myocardial Infarction/mortality , Myocardial Infarction/therapy
12.
Curr Opin Investig Drugs ; 4(6): 696-700, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12901228

ABSTRACT

Advances in preclinical and clinical development have demonstrated that monoclonal antibodies and immuno-activating cytokines have a beneficial role in certain clinical oncology settings. Genetic engineering has now been used to create 'immunocytokines (ICs)'. These are fusion proteins that consist of an immune-activating cytokine linked to a tumor-reactive monoclonal antibody. Preclinical data demonstrate that ICs are far more effective in murine tumor models than the separate molecules from which they are derived. Clinical testing of ICs has recently begun using an anti-GD2 monoclonal antibody linked to interleukin-2 (IL-2) (hu14.18-IL-2), and using an antibody directed against the human epithelial cell adhesion molecule linked to IL-2 (KS-IL-2).


Subject(s)
Antibodies, Monoclonal/therapeutic use , Cytokines/therapeutic use , Technology, Pharmaceutical/methods , Animals , Clinical Trials as Topic/statistics & numerical data , Cytokines/chemical synthesis , Cytokines/immunology , Drug Evaluation, Preclinical/methods , Humans , Technology, Pharmaceutical/trends
16.
Trends Biotechnol ; 18(11): 455-61, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11058786

ABSTRACT

A combination of molecular modelling, conventional epitope scanning and combinatorial techniques, such as phage display and DNA shuffling, has greatly improved our understanding of ligand-receptor interactions. It has therefore been possible to develop powerful cytokine-growth factor antagonists and new designer cytokines, with altered receptor specificities or with greatly enhanced biological activity. Recently, small circular peptides that mimic or block the effects of natural cytokines and growth factors have been developed; such small peptides are likely to open new avenues in therapeutics.


Subject(s)
Cytokines/chemical synthesis , Drug Design , Growth Substances/chemical synthesis , Animals , Biotechnology , Combinatorial Chemistry Techniques , Cytokines/chemistry , Cytokines/metabolism , Epitopes , Growth Substances/chemistry , Growth Substances/metabolism , Humans , Ligands , Models, Molecular , Receptors, Cytokine/metabolism , Receptors, Growth Factor/metabolism , Recombinant Fusion Proteins/metabolism
17.
J Pept Res ; 55(5): 384-97, 2000 May.
Article in English | MEDLINE | ID: mdl-10863935

ABSTRACT

Human pleiotrophin (hPTN), a novel heparin-binding neurotrophic factor consisting of 136 amino acid residues with five intramolecular disulfide bonds, was synthesized by solution procedure in order to demonstrate the utility of our strategy using our newly developed solvent system, a mixture of trifluoroethanol (TFE) and dichloromethane (DCM) or chloroform (CHL). The final protected peptide was synthesized by coupling two larger protected intermediates, Boc-(1-64)-OH and H-(65-136)-OBzl, in CHL/TFE (3:1; v/v) using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) in the presence of 3,4-dihydro-3-hydroxy-4-oxo-1,2,3-benzotriazine (HOOBt). After removal of all protecting groups using the HF procedure followed by treatment with Hg(OAc)2, the fully deprotected peptide was subjected to an oxidative folding reaction. The product was confirmed as having the correct disulfide structure by examining the cystine peptides obtained by enzymatic digestions, and as possessing the same biological activities as those of the natural product. The N- and C-terminal half domains (1-64 and 65-136) were also synthesized, and measurement of their biological activities indicated that the C-terminal half domain displays almost all the activities of the full-length molecule, whereas the N-terminal half domain shows almost no activity. From these results, we were able to confirm that the C-terminal half domain is responsible for the expression of biological activities in the same manner as human midkine (hMK), another heparin-binding neurotrophic growth factor.


Subject(s)
Carrier Proteins/chemistry , Carrier Proteins/chemical synthesis , Cytokines/chemistry , Cytokines/chemical synthesis , Amino Acid Sequence , Amino Acids/chemistry , Animals , Brain/embryology , Carrier Proteins/biosynthesis , Cells, Cultured , Cytokines/biosynthesis , Disulfides , Dose-Response Relationship, Drug , Humans , Mice , Midkine , Molecular Sequence Data , Nerve Growth Factors/chemical synthesis , Nerve Growth Factors/chemistry , Peptide Biosynthesis , Plasminogen Activator Inhibitor 1/biosynthesis , Plasminogen Activator Inhibitor 1/chemistry , Plasminogen Activators/biosynthesis , Plasminogen Activators/chemistry , Protein Folding , Protein Structure, Secondary , Protein Structure, Tertiary , Rats , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Sequence Homology, Amino Acid , Time Factors
18.
Anal Biochem ; 274(1): 104-9, 1999 Oct 01.
Article in English | MEDLINE | ID: mdl-10527502

ABSTRACT

A chemical reagent, N-acetyl-cys((succinimidyl-6-(thioacetyl)amino) hexanoate)-ser-arg-arg-ala-ser-val-tyr-amide ("phosite NHS ester"), allowing the introduction of phosphorylation sites into proteins, peptides, or small molecules, has been synthesized and characterized. The phosite reagent enables the enzymatic radiolabeling of any protein, peptide, or small molecule containing a reactive amine using [(32)P] or [(33)P]ATP and protein kinase A. The utility of the reagent has been demonstrated in cytokine and G protein-coupled radioligand receptor binding assays using whole cell and immobilized receptor formats. Use of the reagent does not require genetic manipulation of the target ligand.


Subject(s)
Carrier Proteins/metabolism , Neurokinin A/chemical synthesis , Phosphopeptides/chemical synthesis , Phosphoproteins/chemical synthesis , Radioligand Assay/methods , Receptors, Cell Surface , Receptors, Neurokinin-2/metabolism , Animals , CHO Cells , Carrier Proteins/analysis , Chromatography, High Pressure Liquid/methods , Cricetinae , Cyclic AMP-Dependent Protein Kinases/chemistry , Cyclic AMP-Dependent Protein Kinases/metabolism , Cytokines/chemical synthesis , Cytokines/metabolism , GTP-Binding Proteins/metabolism , Indicators and Reagents , Isotope Labeling/methods , Leptin/chemical synthesis , Leptin/metabolism , Neurokinin A/metabolism , Oligopeptides , Phosphopeptides/metabolism , Phosphoproteins/metabolism , Phosphorus Radioisotopes , Phosphorylation , Receptors, Leptin , Receptors, Neurokinin-2/analysis , Recombinant Proteins/analysis , Recombinant Proteins/metabolism , Spectrometry, Mass, Secondary Ion/methods , Transfection
19.
Exp Cell Res ; 246(1): 152-64, 1999 Jan 10.
Article in English | MEDLINE | ID: mdl-9882525

ABSTRACT

Rat parenchymal liver cells were cultured in the presence of lethally treated Swiss 3T3 cells. This co-culture allowed hepatocytes to produce colonies containing more than 300 cells in 30 days. Hepatocytes in colonies appeared morphologically normal and some of them were suggested to have bipotental differentiation capacity. The initial growth stimulatory activity of the feeder cells was replaceable with their conditioned medium (CM). Biochemical analysis of an active principle in the 3T3 cell-CM identified pleiotrophin. Pleiotrophin purified from the 3T3 cell-CM, recombinant human pleiotrophin, chemically synthesized human pleiotrophin, and midkine promoted the growth of hepatocytes as well. Reverse transcription-polymerase chain reaction clearly showed that the synthesis of mRNA of pleiotrophin was stimulated in the regenerating liver induced by either partial hepatectomy or the treatment with d-galactosamine, strongly suggesting a biological significance of pleiotrophin in the proliferation of hepatocytes in vivo. From these results we concluded that pleiotrophin is a new potent growth factor for adult parenchymal hepatocytes. This study indicates the importance of mesenchymal stimulation for the growth of adult rat hepatocytes.


Subject(s)
Carrier Proteins/isolation & purification , Carrier Proteins/pharmacology , Cytokines/isolation & purification , Cytokines/pharmacology , Liver/cytology , Mitogens/pharmacology , 3T3 Cells , Animals , Biomarkers/analysis , Carrier Proteins/chemical synthesis , Carrier Proteins/genetics , Cell Division/drug effects , Cells, Cultured , Coculture Techniques , Culture Media, Conditioned/chemistry , Culture Media, Conditioned/pharmacology , Cytokines/chemical synthesis , Cytokines/genetics , DNA/biosynthesis , Galactosamine/pharmacology , Hepatectomy , Humans , Liver/drug effects , Liver Regeneration/drug effects , Liver Regeneration/physiology , Mice , Midkine , Mitogens/chemical synthesis , Mitogens/genetics , Mitogens/isolation & purification , RNA, Messenger/metabolism , Rats , Recombinant Proteins/biosynthesis , Recombinant Proteins/pharmacology , Transcriptional Activation/drug effects
20.
J Biol Chem ; 272(40): 24966-70, 1997 Oct 03.
Article in English | MEDLINE | ID: mdl-9312101

ABSTRACT

Stromal cell-derived factor (SDF) 1 is a potent chemoattractant for leukocytes through activation of the receptor CXCR4/Fusin/LESTR, which is a fusion co-factor for the entry of T lymphocytotropic human immunodeficiency virus type 1 (HIV-1). This CXCR4-mediated HIV-1 fusion can be inhibited by SDF-1. Because of its importance in the study of immunity and AIDS, large scale production of SDF-1 is desirable. In addition to recombinant technology, chemical synthesis provides means by which biologically active proteins can be produced not only in large quantity but also with a variety of designed modifications. In this study, we investigated the binding and function of an SDF-1alpha analogue, N33A, synthesized by a newly developed native chemical ligation approach. Radioiodinated N33A showed high affinity binding to human monocytes, T lymphocytes, as well as neutrophils, and competed equally well with native recombinant SDF-1alpha for binding sites on leukocytes. N33A also showed equally potent chemoattractant activity as native recombinant SDF-1alpha for human leukocytes. Further study with CXCR4/Fusin/LESTR transfected HEK 293 cells showed that N33A binds and induces directional migration of these cells in vitro. These results demonstrate that the chemically synthesized SDF-1alpha analogue, N33A, which can be produced rapidly in large quantity, possesses the same capacity as native SDF-1alpha to activate CXCR4-expressing cells and will provide a valuable agent for research on the host immune response and AIDS.


Subject(s)
Chemokines, CXC , Chemotaxis, Leukocyte/drug effects , Cytokines/pharmacology , Leukocytes/physiology , Membrane Proteins/physiology , Receptors, HIV/physiology , Binding, Competitive , Chemokine CXCL12 , Cytokines/chemical synthesis , Cytokines/metabolism , Humans , In Vitro Techniques , Kinetics , Leukocytes/drug effects , Membrane Proteins/biosynthesis , Monocytes/drug effects , Monocytes/physiology , Neutrophils/drug effects , Neutrophils/physiology , Point Mutation , Receptors, CXCR4 , Receptors, HIV/biosynthesis , Recombinant Fusion Proteins/metabolism , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Recombinant Proteins/pharmacology
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