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1.
Pharm Res ; 38(4): 583-592, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33782838

RESUMO

PURPOSE: The aim of this study was to develop a useful antibody PK evaluation tool using a combination of cassette-dosing and microsampling in mice and monkeys in order to reduce the number of animals used. METHODS: Cetuximab, denosumab, infliximab, and a mixture of the three antibodies, i.e., cassette-dosing, were administered intravenously to cynomolgus monkeys, C57BL/6J mice, and homozygous human neonatal Fc-receptor transgenic (Tg32) mice. Mouse blood was collected from one animal continuously via the jugular vein at nine points. RESULTS: In cynomolgus monkeys, infliximab showed faster elimination in the cassette-dosing group than in the single-dose group. Anti-drug antibody production was observed, but the PK parameters of the clearance and distribution volume were similar in both groups. In C57BL/6J and Tg32 mice, each of the plasma concentrations-time profiles after cassette-dosing were similar to those after single dosing. PK evaluation using a combination of cassette-dosing and microsampling in mice may reduce the number of mice used by approximately 90% compared with the conventional method. CONCLUSIONS: The combination of antibody cassette-dosing and microsampling is a promising PK evaluation method as a high-throughput and reliable with reduced numbers of mice and cynomolgus monkeys.


Assuntos
Alternativas ao Uso de Animais/métodos , Anticorpos Monoclonais/farmacocinética , Animais , Avaliação Pré-Clínica de Medicamentos/métodos , Estudos de Viabilidade , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Macaca fascicularis , Masculino , Camundongos , Camundongos Transgênicos , Modelos Animais , Receptores Fc/genética , Receptores Fc/metabolismo
2.
Biol Pharm Bull ; 44(3): 389-395, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33642546

RESUMO

Human pharmacokinetics (PK) profiles of monoclonal antibodies (mAbs) are usually predicted using non-human primates (NHP), but this comes with drawbacks in terms of cost and throughput. Therefore, we established a human PK profile prediction method using human neonatal Fc receptor (hFcRn) transgenic mice (TgM). We administered launched 13 mAbs to hFcRn TgM and measured the concentration in plasma using electro-chemiluminescence immunoassay. This was then used to calculate PK parameters and predict human PK profiles. The mAbs showed a bi-phased elimination pattern, and clearance (CL) (mL/d/kg) and distribution volume at steady state (Vdss) (mL/kg) ranges were 11.0 to 131 and 110 to 285, respectively. There was a correlation in half-life at elimination phase (t1/2ß) between hFcRn TgM and humans for 10 mAbs showing CL of more than 80% in the elimination phase (R2 = 0.714). Human t1/2ß was predicted using hFcRn TgM t1/2ß; 9 out of 10 mAbs were within 2-fold the actual values, and all mAbs were within 3-fold. Regarding the predicted CL values, 7 out of 10 mAbs were within 2-fold the human values and all mAbs were within 3-fold. Furthermore, even on day 7 the predicted CL values of 8 out of 10 mAbs were within 2-fold the observed value, with all mAbs within 3-fold. These results suggest human PK profiles can be predicted using hFcRn TgM data. These methods can accelerate the development of antibody drugs while also reducing cost and improving throughput.


Assuntos
Anticorpos Monoclonais/farmacocinética , Antígenos de Histocompatibilidade Classe I/genética , Modelos Biológicos , Receptores Fc/genética , Animais , Anticorpos Monoclonais/sangue , Avaliação Pré-Clínica de Medicamentos , Humanos , Camundongos Transgênicos , Modelos Animais
3.
Immunology ; 163(4): 448-459, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33738807

RESUMO

In contrast to humans or rabbits, in which maternal IgG is transmitted to offspring prenatally via the placenta or the yolk sac, large domestic animals such as pigs, cows and sheep transmit IgG exclusively through colostrum feeding after delivery. The extremely high IgG content in colostrum is absorbed by newborns via the small intestine. Although it is widely accepted that the neonatal Fc receptor, FcRn, is the receptor mediating IgG transfer across both the placenta and small intestine, it remains unclear whether FcRn also mediates serum IgG transfer across the mammary barrier to colostrum/milk, especially in large domestic animals. In this study, using a FcRn knockout pig model generated with a CRISPR-Cas9-based approach, we clearly demonstrate that FcRn is not responsible for the IgG transfer from serum to colostrum in pigs, although like in other mammals, it is involved in IgG homeostasis and mediates IgG absorption in the small intestine of newborns.


Assuntos
Colostro/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Intestino Delgado/metabolismo , Placenta/metabolismo , Receptores Fc/metabolismo , Suínos/imunologia , Animais , Animais Geneticamente Modificados , Animais Recém-Nascidos , Aleitamento Materno , Sistemas CRISPR-Cas , Bovinos , Feminino , Técnicas de Inativação de Genes , Antígenos de Histocompatibilidade Classe I/genética , Homeostase , Humanos , Imunidade Materno-Adquirida , Imunoglobulina G/metabolismo , Gravidez , Coelhos , Receptores Fc/genética , Ovinos
4.
J Immunol Methods ; 476: 112683, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31682797

RESUMO

The expression levels of immunoglobulin elements and their receptors are important markers for health and disease. Within the immunoglobulin locus, the constant regions and the variable region families are associated with certain pathologies, yet a holistic view of the interaction between the expressions of the multiple genes remain to be fully characterized. There is thus an important need to quantify antibody elements, their receptors and the receptor subunits in blood (PBMC cDNA) for both screening and detailed studies of such associations. Leveraging on qPCR, we designed primers for all Vκ1-6, VH1-7, Vλ1-11, nine CH isotypes, Cκ, Cκ, Cλ1 &3, FcεRI α,ß, and γ subunits, all three FcγR and their subunits, and FcαR. Validating this on a volunteer PBMC cDNA, we report a qPCR primer set repertoire that can quantify the relative expression of all the above genes to the GAPDH housekeeping gene, with implications and uses in both clinical monitoring and research.


Assuntos
Primers do DNA , Sistema Imunitário/fisiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Receptores Fc/genética , DNA Complementar , Expressão Gênica , Humanos , Cadeias Pesadas de Imunoglobulinas/análise , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Leves de Imunoglobulina/análise , Cadeias Leves de Imunoglobulina/genética , Região Variável de Imunoglobulina/análise , Região Variável de Imunoglobulina/genética , Leucócitos Mononucleares , RNA Mensageiro/análise , Receptores Fc/análise
5.
Drug Metab Dispos ; 47(10): 1111-1121, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31387871

RESUMO

The identification of nonopioid alternatives to treat chronic pain has received a great deal of interest in recent years. Recently, the engineering of a series of Nav1.7 inhibitory peptide-antibody conjugates has been reported, and herein, the preclinical efforts to identify novel approaches to characterize the pharmacokinetic properties of the peptide conjugates are described. A cryopreserved plated mouse hepatocyte assay was designed to measure the depletion of the peptide-antibody conjugates from the media, with a correlation being observed between percentage remaining in the media and in vivo clearance (Pearson r = -0.5525). Physicochemical (charge and hydrophobicity), receptor-binding [neonatal Fc receptor (FcRn)], and in vivo pharmacokinetic data were generated and compared with the results from our in vitro hepatocyte assay, which was hypothesized to encompass all of the aforementioned properties. Correlations were observed among hydrophobicity; FcRn binding; depletion rates from the hepatocyte assay; and ultimately, in vivo clearance. Subsequent studies identified potential roles for the low-density lipoprotein and mannose/galactose receptors in the association of the Nav1.7 peptide conjugates with mouse hepatocytes, although in vivo studies suggested that FcRn was still the primary receptor involved in determining the pharmacokinetics of the peptide conjugates. Ultimately, the use of the cryopreserved hepatocyte assay along with FcRn binding and hydrophobic interaction chromatography provided an efficient and integrated approach to rapidly triage molecules for advancement while reducing the number of in vivo pharmacokinetic studies. SIGNIFICANCE STATEMENT: Although multiple in vitro and in silico tools are available in small-molecule drug discovery, pharmacokinetic characterization of protein therapeutics is still highly dependent upon the use of in vivo studies in preclinical species. The current work demonstrates the combined use of cryopreserved hepatocytes, hydrophobic interaction chromatography, and neonatal Fc receptor binding to characterize a series of Nav1.7 peptide-antibody conjugates prior to conducting in vivo studies, thus providing a means to rapidly evaluate novel protein therapeutic platforms while concomitantly reducing the number of in vivo studies conducted in preclinical species.


Assuntos
Dor Crônica/tratamento farmacológico , Antígenos de Histocompatibilidade Classe I/metabolismo , Imunoconjugados/farmacocinética , Canal de Sódio Disparado por Voltagem NAV1.7/metabolismo , Receptores Fc/metabolismo , Bloqueadores do Canal de Sódio Disparado por Voltagem/farmacocinética , Administração Intravenosa , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/farmacocinética , Criopreservação , Avaliação Pré-Clínica de Medicamentos/métodos , Hepatócitos , Antígenos de Histocompatibilidade Classe I/genética , Imunoconjugados/administração & dosagem , Macaca fascicularis , Masculino , Taxa de Depuração Metabólica , Camundongos , Camundongos Knockout , Peptídeos/administração & dosagem , Peptídeos/farmacocinética , Receptores Fc/genética , Distribuição Tecidual , Bloqueadores do Canal de Sódio Disparado por Voltagem/administração & dosagem
6.
PLoS One ; 13(4): e0195909, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29649283

RESUMO

Eculizumab, a monoclonal antibody (mAb) directed against complement protein C5, is considered to be the current standard of care for patients with paroxysmal nocturnal hemoglobinuria (PNH) and atypical hemolytic uremic syndrome. This study describes the generation and preclinical attributes of ALXN1210, a new long-acting anti-C5 mAb, obtained through select modifications to eculizumab to both largely abolish target-mediated drug disposition (TMDD) and increase recycling efficiency via the neonatal Fc receptor (FcRn). To attenuate the effect of TMDD on plasma terminal half-life (t1/2), histidine substitutions were engineered into the complementarity-determining regions of eculizumab to enhance the dissociation rate of the mAb:C5 complex in the acidic early endosome relative to the slightly basic pH of blood. Antibody variants with optimal pH-dependent binding to C5 exhibited little to no TMDD in mice in the presence of human C5. To further enhance the efficiency of FcRn-mediated recycling of the antibody, two additional substitutions were introduced to increase affinity for human FcRn. These substitutions yielded an additional doubling of the t½ of surrogate anti-mouse C5 antibodies with reduced TMDD in transgenic mice expressing the human FcRn. In conclusion, ALXN1210 is a promising new therapeutic candidate currently in clinical development for treatment of patients with PNH and atypical hemolytic uremic syndrome.


Assuntos
Anticorpos Monoclonais/química , Anticorpos Monoclonais/farmacologia , Complemento C5/antagonistas & inibidores , Desenho de Fármacos , Animais , Anticorpos Monoclonais/farmacocinética , Afinidade de Anticorpos , Avaliação Pré-Clínica de Medicamentos , Hemólise/imunologia , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Cinética , Camundongos , Camundongos Transgênicos , Ligação Proteica , Receptores Fc/genética
7.
Methods Mol Biol ; 1438: 103-14, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27150086

RESUMO

Therapeutic monoclonal antibodies are widely recognized to be a most promising means to treat an increasing number of human diseases, including cancers and autoimmunity. To a large extent, the efficacy of monoclonal antibody treatment is because IgG antibodies have greatly extended persistence in vivo. However, conventional rodent models do not mirror human antibody pharmacokinetics. The key molecule responsible for the extended persistence antibodies is the major histocompatibility complex class I family Fc receptor, FcRn. We describe human FcRn transgenic mouse models and how they can be exploited productively for the preclinical pharmacokinetic evaluation of therapeutic antibodies.


Assuntos
Anticorpos Monoclonais/farmacocinética , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Receptores Fc/genética , Receptores Fc/metabolismo , Animais , Avaliação Pré-Clínica de Medicamentos , Humanos , Imunoglobulinas Intravenosas/farmacocinética , Camundongos , Camundongos Transgênicos
8.
Clin Nutr ; 35(2): 399-407, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26112894

RESUMO

BACKGROUND & AIMS: Intrauterine growth restriction (IUGR) neonates suffer from growth restriction. Tributyrin (TB), a pro-drug of butyrate, can facilitate the growth of animals. This study was to investigate the effects of TB supplementation on the growth of IUGR neonatal piglets. METHODS: Sixteen IUGR and 8 NBW (normal body weight) neonatal piglets were chosen, weaned at 7th day and fed basic milk diets (NBW and IUGR group) or the basic diets supplemented with 0.1% tributyrin (IT group, IUGR piglets fed with tributyrin) until day 21 (n = 8). The body weights of the piglets on days 0, 7, 10, 14, 17, and 20 were measured. The digestive enzyme activity, intestinal morphology, immunoglobulin levels and gene expression of IgG, FcRn and GPR41 in the small intestines were analyzed. RESULTS: The body weights of the piglets in the IUGR and IT group were similar, and both were lower than the NBW group on days 10 and 14. However, after day 17, the IT group exhibited improved (P < 0.05) body weights compared to that of the IUGR group. The piglets were sacrificed on day 21. Compared with the NBW piglets, IUGR impaired the development of immune organs and small intestines, impaired the intestinal villus morphology, decreased (P < 0.05) most of the tested intestinal digestive enzyme activities, decreased (P < 0.05) the ileal sIgA and IgG levels, and down-regulated (P < 0.05) the intestinal IgG and GPR41 expression. Piglets in the IT group exhibited a better-developed (P < 0.05) spleen and small intestines, improved intestinal villus morphology, increased (P < 0.05) intestinal villus surface areas, enhanced (P < 0.05) digestive enzyme activities, and up-regulated (P < 0.05) expression of IgG and GPR41 mRNA compared to those of the IUGR group. CONCLUSIONS: TB supplementation improves the growth and the intestinal digestive and barrier functions in IUGR piglets during the suckling period.


Assuntos
Suplementos Nutricionais , Digestão/efeitos dos fármacos , Retardo do Crescimento Fetal/tratamento farmacológico , Intestinos/efeitos dos fármacos , Triglicerídeos/administração & dosagem , Actinas/genética , Actinas/metabolismo , Animais , Animais Recém-Nascidos , Peso Corporal , Modelos Animais de Doenças , Feminino , Íleo/efeitos dos fármacos , Íleo/crescimento & desenvolvimento , Imunoglobulina A/metabolismo , Imunoglobulina G/genética , Imunoglobulina G/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Intestinos/crescimento & desenvolvimento , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Fc/genética , Receptores Fc/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Baço/efeitos dos fármacos , Baço/metabolismo , Suínos/crescimento & desenvolvimento
9.
Clin Exp Immunol ; 181(3): 407-16, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25907714

RESUMO

The Fc receptor I for IgA (FcαRI) down-regulates humoral immune responses and modulates the risk of autoimmunity. This study aimed to investigate whether FcαRI targeting can affect progression of pristine-induced lupus nephritis. In the first experiment (early intervention), four groups of animals were evaluated: untreated FcαRI/FcRγ transgenic (Tg) mice and Tg mice administered control antibody (Ctr Fab), saline and anti-FcαRI Fab [macrophage inflammatory protein (MIP)-8a], respectively, three times a week for 29 weeks, after being injected once intraperitoneally with 0·5 ml pristane. In the second experiment, antibody injection started after the onset of nephritis and was carried out for 2 months, with similar groups as described above. MIP-8a improved proteinuria, decreased the amounts of glomerular injury markers, serum interleukin (IL)-6, IL-1 and monocyte chemoattractant protein (MCP)-1, and F4/80 macrophages in the interstitium and glomeruli, in both experiments. When MIP-8a was used as early intervention, a decrease in mouse serum anti-nuclear antibody (ANA) titres and reduced deposition of immunoglobulins in glomeruli were observed. This effect was associated with reduced serum titres of immunoglobulin (Ig)G2a but not IgG1, IgG2b and IgG3. Furthermore, pathological analysis showed lower glomerular activity index and less fibronectin in MIP-8a treated mice. This study suggests that FcαRI targeting could halt disease progression and lupus activation by selective inhibition of cytokine production, leucocyte recruitment and renal inflammation. Our findings provide a basis for the use of FcαRI as a molecular target for the treatment of lupus.


Assuntos
Anticorpos Monoclonais/farmacologia , Nefrite Lúpica/prevenção & controle , Terapia de Alvo Molecular/métodos , Receptores Fc/antagonistas & inibidores , Animais , Anticorpos Monoclonais/imunologia , Antígenos CD/genética , Antígenos CD/imunologia , Autoanticorpos/sangue , Autoanticorpos/imunologia , Citocinas/sangue , Citocinas/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Rim/efeitos dos fármacos , Rim/patologia , Rim/ultraestrutura , Nefrite Lúpica/induzido quimicamente , Nefrite Lúpica/imunologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia Eletrônica , Receptores Fc/genética , Receptores Fc/imunologia , Terpenos , Fatores de Tempo
10.
Genet Mol Res ; 14(1): 2461-70, 2015 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-25867392

RESUMO

The neonatal Fc receptor (FcRn) plays an important role in regulating IgG homeostasis in the body and passive protection to the offspring. Changes in FcRn expression levels caused by genetic polymorphisms of Fcgrt, which encodes FcRn, may lead to inter-individual differences in colostrum IgG levels in sheep. In this study, we sequenced the FcRn partial heavy chain from 179 sheep from Xinjiang Province, China, and detected the differences in colostrum IgG levels and Fcgrt genotypes to identify the correlation between the Fcgrt genotype and colostrum IgG levels in 4 sheep breeds. The DNA sequencing of a 680-bp fragment of the Fcgrt gene revealed various patterns depending on the single-strand conformation in the Suffolk breed. Sequencing analysis revealed a total of 3 patterns, AA, BB, AB, in this fragment, among which the absence of AB and BB genotype acted as a marker for breed identification and characterization, while the AA genotype was shared by Suffolk and 3 other breeds. The only allele found in all 4 breeds was allele A, indicating that natural selection may be favoring the AB and BB genotypes in general and B allele in particular, as the colostrum IgG concentration was relatively higher in the Suffolk breed compared to the other 3 breeds.


Assuntos
Colostro/imunologia , Antígenos de Histocompatibilidade Classe I/genética , Imunoglobulina G/metabolismo , Polimorfismo Genético , Receptores Fc/genética , Carneiro Doméstico/genética , Carneiro Doméstico/imunologia , Alelos , Animais , Sequência de Bases , Feminino , Dados de Sequência Molecular , Gravidez , Análise de Sequência de DNA
11.
Inflammation ; 38(2): 632-6, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25012527

RESUMO

The aim of this study was to explore the interaction between FCRL4 gene and environmental factors in patients with ankylosing spondylitis. Two hundred ninety-seven ankylosing spondylitis (AS) Han Chinese patients were selected who were diagnosed at the Department of Rheumatology, First Affiliated Hospital, Anhui Medical University, in accordance with the modified New York criteria. The single nucleotide polymorphism (SNP) was genotyped by multiplex SNaPshot technique. The interaction between FCRL4 gene and ten environmental factors in AS patients was assessed by using a case-only study. The interaction between FCRL4 gene (rs2777963) and environmental factors was analyzed by chi-square test and logistic models. p values, odds ratio, and 95 % confidence intervals (CIs) were used for estimating the effects of interaction. Odds ratio (OR) for the interaction of gene × environment (G × E) between drinking group and non-drinking group was 2.61 [95 % CI (1.30, 5.23), p=0.007], with statistical significance. Within the cooking oil group, there also may be an interaction of G × E between main animal oil and main plant oil [OR=10.55, 95 % CI (5.55, 20.04), p<0.001]. However, there was no interaction between FCRL4 gene and the other eight environmental factors in patients with AS. The observed significant gene-environment interaction suggests that drinking and cooking oil with FCRL4 gene has a significant interaction. Drinking and cooking oil may be risk exposure factors to take a combined action with predisposing genes in patients with AS. A larger sample case-control study is needed to illustrate the interaction mechanism in the further study.


Assuntos
Exposição Ambiental , Receptores Fc/genética , Espondilite Anquilosante/epidemiologia , Espondilite Anquilosante/genética , Adolescente , Adulto , Consumo de Bebidas Alcoólicas/epidemiologia , Povo Asiático/genética , Criança , China/epidemiologia , Gorduras Insaturadas na Dieta , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Adulto Jovem
12.
Nutrition ; 28(3): 275-80, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22305006

RESUMO

OBJECTIVE: This study investigated whether spleen oxidative stress induced by a high-fat diet (HFD) influences the expression of genes involved in B-cell activation, thus leading to B-cell-related immunosuppression. METHODS: Male C57BL/6 mice were randomly assigned to one of three groups with eight mice in each group. The control group consumed an ordinary diet (4.9% fat, w/w). The other two groups were fed an HFD (21.2% fat) and an HFD plus 0.1% lipoic acid (LA). After 10 wk, plasma and spleen oxidative stress biomarkers including superoxide dismutase, catalase, glutathione peroxidase, total antioxidant capacity, reduced glutathione/oxidized glutathione ratio, and malondialdehyde were examined. The B-cell-related immune function was evaluated by examining the number of B cells, and the apoptotic percentages of splenic lymphocytes were determined by flow cytometry. Furthermore, the B-cell activation and reactive oxygen species scavenger-related genes differentially expressed between mice fed an HFD and those fed an HFD supplemented with LA were identified through complementary DNA microarray. RESULTS: The HFD induced marked decreases in the number of B cells and significantly increased the apoptotic percentages of splenic lymphocytes, accompanied by oxidative stress and increased oxidative damage, in the plasma and spleen. In addition, complementary DNA array analysis results showed that the HFD induced the decreased expression of genes associated with antioxidant defense, such as superoxide dismutase-3 (1.5-fold), metallothionein-1 (3.03-fold), glutathione peroxidase-5 (17.15-fold), and peroxiredoxin-4 (1.5), and B-cell activation, such as immunoglobulin heavy chain 6 (2.46-fold), immunoglobulin κ-chain (1.74-fold), Fc receptor (1.41-fold), and RAS-related C3 botulinum substrate-1 (7.46). The LA supplement prevented the buildup of oxidative stress and upregulated related gene expressions. CONCLUSION: These results indicate a role for LA as a possible effective supplement with an HFD to prevent the development of oxidative stress and to attenuate B-cell damnification by increasing the gene expression of the B-cell receptor signaling pathway.


Assuntos
Linfócitos B/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais , Tolerância Imunológica , Estresse Oxidativo/efeitos dos fármacos , Ácido Tióctico/farmacologia , Animais , Antioxidantes/farmacologia , Apoptose , Linfócitos B/imunologia , Linfócitos B/metabolismo , Catalase/sangue , Catalase/genética , Perfilação da Expressão Gênica , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Cadeias kappa de Imunoglobulina/genética , Cadeias kappa de Imunoglobulina/metabolismo , Masculino , Malondialdeído/sangue , Camundongos , Camundongos Endogâmicos C57BL , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Estresse Oxidativo/imunologia , Peroxirredoxinas/genética , Peroxirredoxinas/metabolismo , Espécies Reativas de Oxigênio/sangue , Espécies Reativas de Oxigênio/metabolismo , Receptores Fc/genética , Receptores Fc/metabolismo , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/sangue , Superóxido Dismutase/genética , Regulação para Cima , Proteínas rac de Ligação ao GTP/genética , Proteínas rac de Ligação ao GTP/metabolismo , Proteínas rac1 de Ligação ao GTP
13.
J Pharmacokinet Pharmacodyn ; 39(1): 67-86, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22143261

RESUMO

The objectives of the following investigation were (1) development of a physiologically based pharmacokinetic (PBPK) model capable of characterizing the plasma and tissue pharmacokinetics (PK) of nonspecific or antigen specific monoclonal antibodies (mAbs) in wild type, FcRn knockout, tumor bearing and non tumor bearing mice and (2) evaluation of the scale up potential of the model by characterizing the mouse, rat, monkey and human plasma PK of mAbs, simultaneously. A PBPK model containing 15 tissues, a carcass and a tumor compartment was developed by modifying/augmenting previously published PBPK models. Each tissue compartment was subdivided into plasma, blood cell, endothelial, interstitial and cellular sub-compartments. Each tissue was connected through blood and lymph flow to the systemic circulation. Lymph flow was set to a value 500 times lower than plasma flow and vascular reflection coefficients for each tissue were adjusted according to their vascular pore size. In each tissue endothelial space, mAb entered via pinocytosis and the interaction of FcRn with mAb was described by on and off rates. FcRn bound mAb was recycled and unbound mAb was eliminated by a first order process (K(deg)). The PBPK model was simultaneously fit to the following datasets to estimate four system parameters: (1) plasma and tissue PK of nonspecific mAb in wild type mouse with or without simultaneous intravenous immunoglobulin (IVIG) administration, (2) plasma and tissue PK of nonspecific mAb in FcRn knockout mouse, (3) plasma and tissue PK of nonspecific mAb in tumor bearing mouse, (4) plasma and tissue PK of tumor antigen specific mAb in tumor bearing mouse, and (5) plasma PK of mAb in rat, monkey and human. The model was able to characterize all the datasets reasonably well with a common set of parameters. The estimated value of the four system parameters i.e. FcRn concentration (FcRn), rate of pinocytosis per unit endosomal space (CL(up)), K(deg) and the proportionality constant (C_LNLF) between the rate at which antibody transfers from the lymph node compartment to the blood compartment and the plasma flow of the given species, were found to be 4.98E-05 M (CV% = 11.1), 3.66E-02 l/h/l (%CV = 3.48), 42.9 1/h (%CV = 15.7) and 9.1 (CV% > 50). Thus, a platform PBPK model has been developed that can not only simultaneously characterize mAb disposition data obtained from various previously published mouse PBPK models but is also capable of characterizing mAb disposition in various preclinical species and human.


Assuntos
Anticorpos Monoclonais/sangue , Anticorpos Monoclonais/farmacocinética , Modelos Biológicos , Adalimumab , Algoritmos , Estruturas Animais/metabolismo , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Anticorpos Monoclonais Humanizados/sangue , Anticorpos Monoclonais Humanizados/farmacocinética , Antígenos de Neoplasias/imunologia , Área Sob a Curva , Sangue/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Endossomos/metabolismo , Espaço Extracelular/metabolismo , Haplorrinos , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Imunoglobulinas Intravenosas/administração & dosagem , Imunoglobulinas Intravenosas/metabolismo , Imunoglobulinas Intravenosas/farmacologia , Linfa/metabolismo , Masculino , Camundongos , Camundongos Knockout , Neoplasias/imunologia , Neoplasias/metabolismo , Pinocitose/fisiologia , Ratos , Receptores Fc/genética , Receptores Fc/metabolismo , Distribuição Tecidual/efeitos dos fármacos , Distribuição Tecidual/fisiologia , Ensaios Antitumorais Modelo de Xenoenxerto
14.
J Immunol Methods ; 375(1-2): 20-9, 2012 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-21939661

RESUMO

The MHC class-I related receptor or neonatal Fc receptor (FcRn) protects IgG and albumin from degradation by rescuing them in endothelial cells in a pH dependent fashion and consequently increases their respective half-lives. Monoclonal antibody-based therapies are of increasing interest and characterizing the interaction with FcRn is important for the development of an antibody candidate. In order to facilitate the production of soluble FcRn suitable for interaction studies, we generated semi-stable pools co-expressing FcRn α-chain, ß2-microglobulin, biotin ligase and EGFP using a dual promoter, multi-cistronic vector. Human and mouse FcRn were purified in the mg/L range of culture medium and a single purification step was sufficient to reach a high level of purity. The receptors were characterized by ELISA, flow cytometry and surface plasmon resonance and shown to be functional. The single site biotinylation facilitated the directional immobilization of FcRn on the sensor chip and significantly increased the response level of the surface compared to amine coupling used in previous studies. Using this system, the affinity constants of seven IgGs, from various species and isotypes, were determined for human and mouse FcRn, including two hamster isotypes. These results confirm the higher selectivity of the human receptor and the promiscuous binding of mFcRn to IgGs from different species.


Assuntos
Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Receptores Fc/genética , Receptores Fc/imunologia , Animais , Anticorpos Monoclonais/imunologia , Biotinilação/métodos , Células Cultivadas , Cricetinae , DNA Complementar/genética , Vetores Genéticos/genética , Antígenos de Histocompatibilidade Classe I/biossíntese , Humanos , Imunoglobulina G/imunologia , Cinética , Camundongos , Ligação Proteica , Receptores Fc/biossíntese , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Ressonância de Plasmônio de Superfície/métodos
15.
Proc Natl Acad Sci U S A ; 107(51): 22122-7, 2010 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-21135226

RESUMO

Rheumatoid arthritis (RA) is a chronic inflammatory disease marked by bone and cartilage destruction. Current biologic therapies are beneficial in only a portion of patients; hence small molecules targeting key pathogenic signaling cascades represent alternative therapeutic strategies. Here we show that c-Jun N-terminal kinase (JNK) 1, but not JNK2, is critical for joint swelling and destruction in a serum transfer model of arthritis. The proinflammatory function of JNK1 requires bone marrow-derived cells, particularly mast cells. Without JNK1, mast cells fail to degranulate efficiently and release less IL-1ß after stimulation via Fcγ receptors (FcγRs). Pharmacologic JNK inhibition effectively prevents arthritis onset and abrogates joint swelling in established disease. Hence, JNK1 controls mast cell degranulation and FcγR-triggered IL-1ß production, in addition to regulating cytokine and matrix metalloproteinase biosynthesis, and is an attractive therapeutic target in inflammatory arthritis.


Assuntos
Artrite/metabolismo , Degranulação Celular , Interleucina-1beta/biossíntese , Mastócitos/metabolismo , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , Transdução de Sinais , Animais , Artrite/genética , Artrite/imunologia , Artrite/patologia , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Colagenases/biossíntese , Colagenases/genética , Colagenases/imunologia , Regulação da Expressão Gênica/imunologia , Humanos , Inflamação/genética , Inflamação/imunologia , Inflamação/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Mastócitos/imunologia , Mastócitos/patologia , Camundongos , Camundongos Knockout , Proteína Quinase 8 Ativada por Mitógeno/genética , Proteína Quinase 8 Ativada por Mitógeno/imunologia , Proteína Quinase 9 Ativada por Mitógeno/genética , Proteína Quinase 9 Ativada por Mitógeno/imunologia , Proteína Quinase 9 Ativada por Mitógeno/metabolismo , Receptores Fc/genética , Receptores Fc/imunologia , Receptores Fc/metabolismo
16.
Anim Biotechnol ; 20(4): 242-6, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19937499

RESUMO

In this study, we evaluated haplotypes of the bovine FCGRT (encoding the FcRn heavy chain) and their relationship to the IgG concentration in bovine colostrum. Four single nucleotide polymorphism (SNP), classified into five haplotypes, were identified in a total of 49 Holstein-Frisians cows. Haplotype 5 was found to be significantly associated with a high IgG level ([OR] = 9.90, 95%CI = 1.11-88.34, p = 0.016) and haplotype 2 exhibited a similar trend ([OR] = 2.89, 95%CI = 1.17-7.11, p = 0.019).


Assuntos
Bovinos/genética , Colostro/química , Antígenos de Histocompatibilidade Classe I/genética , Imunoglobulina G/análise , Polimorfismo de Nucleotídeo Único , Receptores Fc/genética , Alelos , Animais , Bovinos/imunologia , Colostro/imunologia , Haplótipos , Antígenos de Histocompatibilidade Classe I/imunologia , Imunoglobulina G/imunologia , Receptores Fc/imunologia
18.
J Dairy Res ; 72 Spec No: 107-12, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16180728

RESUMO

In ruminants, protective immunoglobulins are transferred to the newborn via colostrum to mediate maternal immunity. There is a high selectivity in the transport of immunoglobulins from the maternal plasma across the mammary barrier into the colostrum, and only IgG1 is transferred in large amounts. We have recently analysed the expression of the neonatal Fc receptor (FcRn) in sheep mammary gland around parturition. Re-analysing this issue in bovine confirmed our previous data indicating that FcRn is homogeneously localized in the mammary gland acinar cells before parturition, however a remarkable difference was observed in the pattern after calving, where only the apical side of the cells was strongly stained. The presence of the FcRn in the acinar epithelial cells of the mammary gland and the obvious change in distribution before and after parturition indicate that FcRn plays an important role in the IgG transport during colostrum formation in ruminants.


Assuntos
Animais Recém-Nascidos , Bovinos , Expressão Gênica , Glândulas Mamárias Animais/química , Receptores Fc/genética , Animais , Transporte Biológico , Colostro/imunologia , Células Epiteliais/química , Feminino , Imunoglobulina G/metabolismo , Imuno-Histoquímica , Hibridização In Situ , Glândulas Mamárias Animais/crescimento & desenvolvimento , Parto , Gravidez , Receptores Fc/análise , Receptores Fc/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Distribuição Tecidual
19.
Lupus ; 14(6): 458-66, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16038110

RESUMO

The metabolism of radioiodinated mouse IgG was studied in mice with lupus-like syndrome before and after the onset of the disease. Before the onset of the disease, the pharmacokinetic parameters of IgG in MLR-1pr and Pristane-primed Balb/c mice were within the normal range of values. After the onset of the disease a considerable increase in the catabolic rate of IgG was recorded abbreviating its half life to less than one third of the normal value. The increased catabolism of IgG could not be related to the concentration--catabolism effect or to the presence of rheumatoid factor and autoantibody or to the IgG loss through the kidney and gastrointestinal tract. The hypercatabolism of IgG was explained by disease-induced impairment of the function of the receptor FcRn, which regulates the homeostasis of IgG.


Assuntos
Imunoglobulina G/metabolismo , Lúpus Eritematoso Sistêmico/imunologia , Animais , Sequência de Bases , Galinhas , DNA Complementar/genética , Modelos Animais de Doenças , Feminino , Expressão Gênica , Meia-Vida , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Imunoglobulina A/metabolismo , Imunoglobulinas/metabolismo , Radioisótopos do Iodo , Cinética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos MRL lpr , Receptores Fc/genética , Receptores Fc/metabolismo , Terpenos/toxicidade
20.
FASEB J ; 19(2): 272-4, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15545302

RESUMO

Epidemiological evidence links consumption of lycopene, the red carotenoid of tomato, to reduced prostate cancer risk. We investigated the effect of lycopene in normal prostate tissue to gain insight into the mechanisms, by which lycopene can contribute to primary prostate cancer prevention. We supplemented young rats with 200 ppm lycopene for up to 8 wk, measured the uptake into individual prostate lobes, and analyzed lycopene-induced gene regulations in dorsal and lateral lobes after 8 wk of supplementation. Lycopene accumulated in all four prostate lobes over time, with all-trans lycopene being the predominant isoform. The lateral lobe showed a significantly higher total lycopene content than the other prostate lobes. Transcriptomics analysis revealed that lycopene treatment mildly but significantly reduced gene expression of androgen-metabolizing enzymes and androgen targets. Moreover, local expression of IGF-I was decreased in the lateral lobe. Lycopene also consistently reduced transcript levels of proinflammatory cytokines, immunoglobulins, and immunoglobulin receptors in the lateral lobe. This indicates that lycopene reduced inflammatory signals in the lateral prostate lobe. In summary, we show for the first time that lycopene reduced local prostatic androgen signaling, IGF-I expression, and basal inflammatory signals in normal prostate tissue. All of these mechanisms can contribute to the epidemiologically observed prostate cancer risk reduction by lycopene.


Assuntos
Biomarcadores/metabolismo , Carotenoides/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Próstata/efeitos dos fármacos , Próstata/metabolismo , Androgênios/metabolismo , Animais , Carotenoides/farmacocinética , Citocinas/genética , Regulação para Baixo/efeitos dos fármacos , Nível de Saúde , Imunoglobulinas/genética , Inflamação/genética , Inflamação/metabolismo , Fator de Crescimento Insulin-Like I/genética , Licopeno , Masculino , Próstata/química , Próstata/crescimento & desenvolvimento , Ratos , Receptores Fc/genética , Transdução de Sinais/efeitos dos fármacos
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