RESUMO
In the second antibody modeling assessment, we used a semiautomated template-based structure modeling approach for 11 blinded antibody variable region (Fv) targets. The structural modeling method involved several steps, including template selection for framework and canonical structures of complementary determining regions (CDRs), homology modeling, energy minimization, and expert inspection. The submitted models for Fv modeling in Stage 1 had the lowest average backbone root mean square deviation (RMSD) (1.06 Å). Comparison to crystal structures showed the most accurate Fv models were generated for 4 out of 11 targets. We found that the successful modeling in Stage 1 mainly was due to expert-guided template selection for CDRs, especially for CDR-H3, based on our previously proposed empirical method (H3-rules) and the use of position specific scoring matrix-based scoring. Loop refinement using fragment assembly and multicanonical molecular dynamics (McMD) was applied to CDR-H3 loop modeling in Stage 2. Fragment assembly and McMD produced putative structural ensembles with low free energy values that were scored based on the OSCAR all-atom force field and conformation density in principal component analysis space, respectively, as well as the degree of consensus between the two sampling methods. The quality of 8 out of 10 targets improved as compared with Stage 1. For 4 out of 10 Stage-2 targets, our method generated top-scoring models with RMSD values of less than 1 Å. In this article, we discuss the strengths and weaknesses of our approach as well as possible directions for improvement to generate better predictions in the future.
Assuntos
Região Variável de Imunoglobulina/química , Imunoglobulinas/química , Simulação de Dinâmica Molecular , Sequência de Aminoácidos , Animais , Anticorpos/química , Regiões Determinantes de Complementaridade/química , Biologia Computacional/métodos , Bases de Dados de Proteínas , Humanos , Dados de Sequência Molecular , Conformação ProteicaRESUMO
Systemic lupus erythematosus (SLE) is an autoimmune disease involving multi-organ systems with a widely heterogeneous clinical presentation. Renal involvement, observed mainly in lupus nephritis (LN), is the most common organ lesion associated with SLE and a determinant of prognosis. However, treatment of LN remains controversial and challenging, prompting the need for novel therapeutic approaches. In particular, development of a clinically relevant LN animal model would greatly facilitate the development of new treatments. Here, we report a novel murine model for LN established by administering polyinosinic-polycytidylic acid (Poly (I:C)) to NZB/W F1 mice. We investigated the effectiveness of administering Poly (I:C) to NZB/W F1 mice for accelerating nephritis onset and explored the optimal conditions under which to enroll mice with nephritis with similar pathology for studying treatment candidates. Gene-expression analysis revealed that activation of macrophages, which are reported to be involved in the progression of LN in patients, was a unique characteristic in this accelerated nephritis model. Evaluation of the therapeutic effect of mycophenolate mofetil (MMF), a recommended first-choice agent for LN, in this novel LN model showed that MMF significantly reduced proteinuria. The cathepsin S (CatS) inhibitor ASP1617, which has been reported to prevent development of lupus-like glomerulonephritis in the spontaneous NZB/W F1 mouse model, also showed marked therapeutic effect in this model. Our novel Poly (I:C) accelerated LN model would thus be very useful for screening clinical candidates for LN, and CatS may be an attractive therapeutic target for the treatment of LN.
Assuntos
Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Camundongos , Animais , Nefrite Lúpica/induzido quimicamente , Nefrite Lúpica/tratamento farmacológico , Ácido Micofenólico/farmacologia , Ácido Micofenólico/uso terapêutico , Modelos Animais de Doenças , Poli I-C/farmacologia , Camundongos Endogâmicos NZB , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Imunossupressores/farmacologia , Imunossupressores/uso terapêuticoRESUMO
The synthesis and structure-activity relationships of ureas as CCR3 antagonists are described. Optimization starting with lead compound 2 (IC(50)=190 nM) derived from initial screening hit compound 1 (IC(50)=600 nM) led to the identification of (S)-N-((1R,3S,5S)-8-((6-fluoronaphthalen-2-yl)methyl)-8-azabicyclo[3.2.1]octan-3-yl)-N-(2-nitrophenyl)pyrrolidine-1,2-dicarboxamide 27 (IC(50)=4.9 nM) as a potent CCR3 antagonist.
Assuntos
Receptores CCR3/antagonistas & inibidores , Ureia/análogos & derivados , Avaliação Pré-Clínica de Medicamentos , Humanos , Naftalenos/síntese química , Naftalenos/química , Naftalenos/metabolismo , Prolina/química , Ligação Proteica , Pirrolidinas/síntese química , Pirrolidinas/química , Pirrolidinas/metabolismo , Receptores CCR3/metabolismo , Relação Estrutura-Atividade , Ureia/síntese química , Ureia/metabolismoRESUMO
Optimization starting with our lead compound 1 (IC(50)=4.9 nM) led to the identification of pyrrolidinyl phenylurea derivatives. Further modification toward improvement of the bioavailability provided (R)-1-(1-((6-fluoronaphthalen-2-yl)methyl)pyrrolidin-3-yl)-3-(2-(2-hydroxyethoxy)phenyl)urea 32 (IC(50)=1.7 nM), a potent and orally active CCR3 antagonist.
Assuntos
Compostos de Fenilureia/química , Pirrolidinas/química , Receptores CCR3/antagonistas & inibidores , Administração Oral , Animais , Disponibilidade Biológica , Meia-Vida , Macaca fascicularis , Compostos de Fenilureia/síntese química , Compostos de Fenilureia/farmacocinética , Pirrolidinas/síntese química , Pirrolidinas/farmacocinética , Receptores CCR3/metabolismoRESUMO
Non-human primate (NHP) renal transplantation models are widely used vivo models for researching new immunosuppressive therapies including allograft tolerance strategies. To enroll animals into a tolerance study, an immunosuppressive regimen that efficiently establishes stable renal function in NHPs is needed. Here, we assessed the effect of triple therapy comprising 2.0 mg/kg tacrolimus, mycophenolate mofetil and a steroid and its success rate for achieving stable renal function. In addition, to predict the pathophysiological consequences of withdrawing immunosuppressants, an indispensable process after induction of tolerance, we also assessed changes in the stable renal state maintained by triple therapy after drug withdrawal. Six cynomolgus monkeys were used. The median survival time was >176 days over the dosing period and 45 days after drug withdrawal. The triple therapy successfully induced stable graft function without calcineurin inhibitor nephrotoxicity in three of six recipients, although adopting trough-dependent tacrolimus dose adjustment rather than a preset dose regimen could improve on the present strategy. Further, drug withdrawal led to deterioration of renal function, de novo donor specific antibody production and increased the memory/naïve T cell ratio within two weeks post drug withdrawal. We expect that these findings contribute to establish one of the choices for animal model for evaluating future tolerance therapy for renal transplantation.
Assuntos
Transplante de Rim , Animais , Tacrolimo/uso terapêutico , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/prevenção & controle , Ácido Micofenólico/uso terapêutico , Imunossupressores/uso terapêutico , Imunossupressores/farmacologia , Primatas , Inibidores de Calcineurina/uso terapêutico , Sobrevivência de Enxerto , Quimioterapia CombinadaRESUMO
Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the dysregulation of various cell types and immunological pathways. Autoantibodies play an important role in its pathogenesis. The presence of autoantibodies suggests that self-antigen presentation through major histocompatibility complex (MHC) class II on antigen presenting cells is involved in the pathogenesis of autoimmune diseases, including SLE. Cathepsin S (CatS) is a key protease for antigen peptide loading onto lysosomal/endosomal MHC class II molecules through invariant chain degradation to promote antigen presentation. Inhibition of CatS is therefore expected to suppress antigen presentation via MHC class II, T and B cell activation, and antibody production from B cells. Here, we report the pharmacological profile of ASP1617, a novel CatS inhibitor. ASP1617 induced invariant chain accumulation and decreased the expression level of MHC class ΙΙ on the cell surface in both mouse and human B cells. Further, ASP1617 prevented DO11.10 mice T cell proliferation to ovalbumin antigen. We investigated the effects of ASP1617 and mycophenolate mofetil (MMF) on the development of lupus-like nephritis in NZB/W F1 mice, a widely used SLE mouse model. Oral administration of ASP1617 suppressed anti-dsDNA IgG, prevented progression of lupus-like glomerulonephritis, and significantly prevented proteinuria excretion. In contrast, MMF did not suppress anti-dsDNA IgG. Further, we found that plasma and/or urine CatS levels were increased in specimens from NZB/W F1 mice and several SLE patients. These results indicate that CatS may be an attractive therapeutic target for the treatment of SLE.
Assuntos
Catepsinas/antagonistas & inibidores , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Inibidores de Proteases/farmacologia , Administração Oral , Animais , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Endogâmicos NZB , Inibidores de Proteases/administração & dosagem , Inibidores de Proteases/uso terapêuticoRESUMO
B cell-targeted therapies have evolved as established therapies for systemic lupus erythematosus (SLE); however, existing approaches still do not thoroughly satisfy clinical requirements due to limited efficacy against memory B cells, autoantibody-producing plasmablasts and disease heterogeneity. To provide a new treatment option for SLE, we created a novel anti-Igß antibody with enhanced affinity for Fc gamma receptor (FcγR) IIB called ASP2713. ASP2713 cross-reacted with both human and cynomolgus monkey Igß and showed increased binding affinity for human and monkey FcγRIIB compared to native human IgG1. This binding property allows dominant B cell binding and induction of intrinsic negative feedback signals. In human B cells, ASP2713 significantly and concentration-dependently induced FcγRIIB ITIM phosphorylation, while suppressing proliferation under B cell receptor stimulation. This pharmacological effect was also confirmed in in vitro B cell proliferation and antibody production assays using peripheral B cells isolated from patients with SLE. In a cynomolgus monkey tetanus toxoid-induced antibody production model, ASP2713 almost completely inhibited the increase in antigen-specific antibodies with superior efficacy to rituximab. Additionally, ASP2713 significantly suppressed recall antibody production in response to secondary tetanus toxoid immunization, indicating the memory B cell- and plasmablast-targeting potential of ASP2713. Our results suggest that ASP2713 may have therapeutic potential as a treatment for SLE, where B cells play a pathogenic role.
Assuntos
Anticorpos Biespecíficos/metabolismo , Anticorpos Monoclonais/metabolismo , Anticorpos Monoclonais/uso terapêutico , Subpopulações de Linfócitos B/imunologia , Antígenos CD79/metabolismo , Lúpus Eritematoso Sistêmico/terapia , Receptores de IgG/metabolismo , Animais , Anticorpos Biespecíficos/uso terapêutico , Proliferação de Células , Células Cultivadas , Humanos , Tolerância Imunológica , Imunoterapia/métodos , Lúpus Eritematoso Sistêmico/imunologia , Ativação Linfocitária , Macaca fascicularis , Ligação ProteicaRESUMO
Phosphoinositide 3-kinases generate lipid-based second messengers that control an array of intracellular signaling pathways. In particular, phosphoinositide 3-kinases delta (PI3Kδ) is expressed primarily in hematopoietic cells and plays an important role in B-cell development and function. B cells play a critical role in autoimmune diseases by producing autoantibodies. Studies have therefore increasingly focused on PI3Kδ as a therapeutic target for the treatment of inflammatory and autoimmune diseases. One such autoimmune disease is systemic lupus erythematosus (SLE). SLE is a chronic systemic autoimmune disease with repeated recurrence and remission, and autoantibodies play an important role in its pathogenesis. Here, we examined the pharmacological profile of the novel PI3Kδ selective inhibitor AS2819899 and investigated its therapeutic potential against SLE in a NZB/W F1 mouse lupus-like nephritis model, a widely-used SLE mouse model. AS2819899 prevented B and T cell activation in vitro, and inhibited antibody production in a T-cell independent de novo antibody production mouse model. In the spontaneous NZB/W F1 mouse model, AS2819899 treatment significantly reduced anti-dsDNA antibody titers and improved kidney dysfunction. Further, AS2819899 inhibited the memory recall reaction in a T-cell dependent antibody production mouse model, suggesting that AS2819899 can potentially maintain remission of SLE. Moreover, we identified a pharmacodynamics marker for AS2819899 that may be useful in clinical studies. These results indicate that AS2819899 may be an attractive therapeutic candidate for SLE, including the maintenance of remission.
Assuntos
Classe I de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Nefrite Lúpica/tratamento farmacológico , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Modelos Animais de Doenças , Feminino , Imunoglobulina M/imunologia , Nefrite Lúpica/imunologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NZB , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologiaRESUMO
Our laboratory has identified several acrylamide derivatives with potent CCR3 inhibitory activity. In the present study, we evaluated the in vitro metabolic stability (CL(int); mL/min/kg) of these compounds in human liver microsomes (HLMs), and assessed the relationship between their structures and CL(int) values. Among the compounds identified, N-{(3R)-1-[(6-fluoro-2-naphthyl)methyl]pyrrolidin-3-yl}-2-[1-(2-hydroxybenzoyl)piperidin-4-ylidene]acetamide (30j) was found to be a potent inhibitor (IC(50)=8.4nM) with a high metabolic stability against HLMs.
Assuntos
Acetamidas/síntese química , Acrilamidas/química , Antialérgicos/síntese química , Naftalenos/síntese química , Receptores CCR3/antagonistas & inibidores , Acetamidas/química , Acetamidas/farmacologia , Acrilamidas/síntese química , Acrilamidas/farmacocinética , Animais , Antialérgicos/química , Antialérgicos/farmacocinética , Haplorrinos , Humanos , Camundongos , Microssomos Hepáticos/metabolismo , Naftalenos/química , Naftalenos/farmacologia , Piperidinas/síntese química , Piperidinas/química , Piperidinas/farmacologia , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/metabolismo , Receptores CCR3/metabolismo , TermodinâmicaRESUMO
Long-term graft survival after organ transplantation is difficult to achieve because of the development of chronic rejection. One cause of chronic rejection arises from antibody-mediated rejection (AMR), which is dependent on the production of donor-specific antibodies (DSA). Current immunosuppression in organ transplantation is effective in preventing acute T cell-mediated rejection, but the risk of DSA production and graft loss due to AMR remains unchanged. Phosphatidylinositol-3-kinase p110δ (PI3Kδ), a member of the family of PI3K lipid kinases, is a key mediator of B cell activation, proliferation and antibody production. AS2541019 is a novel PI3Kδ selective inhibitor that prevents antibody production by inhibiting B cell immunity. The purpose of this study was to evaluate the inhibitory effect of AS2541019 on DSA production in preclinical rodent and non-human primate allotransplant models. Concomitant administration of AS2541019 with tacrolimus and mycophenolate mofetil (MMF) inhibited de novo DSA production in an ACI-to-Lewis rat cardiac allotransplant model. To predict the efficacy of AS2541019 in clinical practice, we evaluated its effects in cynomolgus monkeys. AS2541019 inhibited B cell proliferation and major histocompatibility complex (MHC) class II expression on B cells in cynomolgus monkeys. Oral administration of AS2541019 inhibited MHC class II expression on peripheral B cells and anti-tetanus toxoid antibody production. In cynomolgus monkey renal allotransplant model, concomitant administration of AS2541019 with tacrolimus and MMF significantly inhibited de novo DSA production. Together, our findings indicate that the PI3Kδ selective inhibitor AS2541019 is a potential candidate for preventing AMR development by inhibiting DSA production.
Assuntos
Formação de Anticorpos/efeitos dos fármacos , Classe I de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Transplante de Coração , Transplante de Rim , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Memória Imunológica , Imunossupressores/farmacologia , Macaca fascicularis , Masculino , Ácido Micofenólico/farmacologia , Ratos , Ratos Endogâmicos ACI , Ratos Endogâmicos Lew , Tacrolimo/farmacologia , Toxoide Tetânico/administração & dosagemRESUMO
Interleukin (IL)-23 is thought to be critical in the pathogenesis of psoriasis, and anti-IL-23 monoclonal antibodies (mAbs) have been approved for the treatment of psoriasis. We speculated that an anti-IL-23 receptor mAb might have greater efficacy than an anti-IL-23 mAb in the treatment of local inflamed lesions with high IL-23 levels. We previously generated an anti-human IL-23 receptor mAb, AS2762900-00, which potently blocked IL-23-induced cell proliferation, regardless of the concentration of IL-23. Here, we evaluated the therapeutic potential of AS2762900-00 in the treatment of psoriasis. Compared with untreated control, AS2762900-00 significantly reduced the epidermal thickness of lesions in a clinically relevant psoriatic human skin xenograft model. The expression of inflammatory genes including genes downstream of IL-23 signaling in the lesion tended to be lower in the AS2762900-00 group than the untreated group, suggesting that the inhibitory effects of AS2762900-00 in the psoriatic human skin xenograft model might occur via blockade of IL-23 signaling pathways. Further, AS2762900-00 showed an inhibitory effect on signal transducer and activator of transcription 3 (STAT3) phosphorylation as a downstream signal of IL-23 receptor activation in whole blood from patients with psoriasis. We also confirmed that AS2762900-00 inhibited IL-23-induced STAT3 phosphorylation in a concentration-dependent manner using whole blood from healthy donors. These data suggest that AS2762900-00 is a promising drug candidate for the treatment of psoriasis. In addition, STAT3 phosphorylation in whole blood may be a useful biomarker for the evaluation of the pharmacodynamic effects of AS2762900-00 in healthy volunteers in clinical development.
Assuntos
Anticorpos Monoclonais/farmacologia , Psoríase/tratamento farmacológico , Receptores de Interleucina/imunologia , Fator de Transcrição STAT3/metabolismo , Pele/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Feminino , Humanos , Hiperplasia/prevenção & controle , Imunoglobulina G/imunologia , Camundongos , Fosforilação/efeitos dos fármacos , Psoríase/imunologia , Psoríase/metabolismo , Pele/imunologia , Pele/patologia , Transplante HeterólogoRESUMO
Sphingosine-1-phosphate (S1P) is a biologically active sphingolipid that acts through the members of a family of 5 G protein-coupled receptors (S1P1 to S1P5). Among these, S1P1 is a major regulator of lymphocyte trafficking. Fingolimod, whose active metabolite, fingolimod phosphate, acts as a nonselective S1P-receptor agonist, exerts its immunomodulatory effect, at least in part, by regulating lymphocyte trafficking via downregulation of S1P1 expression on lymphocytes. Here, we describe the pharmacologic profile of a novel S1P1 agonist, ASP1126. ASP1126 preferentially activated S1P1 compared to S1P3 in rat and human guanosine-5'-(γ-thio)-triphosphate (GTPγS) assays. Oral single administration of ASP1126 decreased the number of peripheral lymphocytes and repeated dosing showed a cumulative effect on lymphopenia in both rats and monkeys. ASP1126 prolonged allograft survival in a rat heterotopic heart transplantation model in combination with a subtherapeutic dose of tacrolimus that was independent of drug-drug interactions. In addition, in nonhuman primate (NHP) renal transplantation, pretreatment with ASP1126 reduced not only the number of naive T cells and central memory T cells but also effector memory T cells in the peripheral blood, all of which could contribute to acute graft rejection and prolonged allograft survival in combination with tacrolimus. Further, we confirmed that ASP1126 has a broad ranging safety margin with respect to its effect on lung weight in rats and bradycardia in NHPs, which were the adverse events found in clinical studies of fingolimod. ASP1126 with improved safety profile has the potential to be an adjunct therapy in combination with tacrolimus in clinical transplantation.
Assuntos
Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/efeitos dos fármacos , Imunossupressores/farmacologia , Lisofosfolipídeos/agonistas , Esfingosina/análogos & derivados , Aloenxertos/efeitos dos fármacos , Aloenxertos/metabolismo , Animais , Bradicardia/induzido quimicamente , Sinergismo Farmacológico , Humanos , Linfócitos/efeitos dos fármacos , Macaca fascicularis , Masculino , Ratos , Esfingosina/agonistas , Tacrolimo/farmacologia , Transplante Homólogo/métodosRESUMO
A novel class of potent CCR3 receptor antagonists were designed and synthesized starting from N-{1-[(6-fluoro-2-naphthyl)methyl]piperidin-4-yl}benzamide (1),which was found by subjecting our chemical library to high throughput screening (HTS). The CCR3 inhibitory activity of the synthesized compounds against eotaxin-induced Ca(2+) influx was evaluated using CCR3-expressing preB cells. Systematic chemical modifications of 1 revealed that the 6-fluoro-2-naphthylmethyl moiety was essential for CCR3 inhibitory activity in this new series of CCR3 antagonists. Further structural modifications of the benzamide and piperidine moieties of 1 led to the identification of exo-N-{8-[(6-fluoro-2-naphthyl)methyl]-8-azabicyclo[3.2.1]oct-3- yl}biphenyl-2-carboxamide [corrected] (31) as a potent CCR3 antagonist with an IC(50) value of 0.020 microM.
Assuntos
Benzamidas/farmacologia , Receptores CCR3/antagonistas & inibidores , Benzamidas/síntese química , Cálcio/metabolismo , Quimiocina CCL11 , Humanos , Concentração Inibidora 50 , Células Precursoras de Linfócitos B , Bibliotecas de Moléculas Pequenas , Relação Estrutura-AtividadeRESUMO
In our previous study on discovering novel types of CCR3 antagonists, we found a fluoronaphthalene derivative (1) that exhibited potent CCR3 inhibitory activity with an IC(50) value of 20 nM. However, compound 1 also inhibited human cytochrome P450 2D6 (CYP2D6) with an IC(50) value of 400 nM. In order to reduce its CYP2D6 inhibitory activity, we performed further systematic structural modifications on 1. In particular, we focused on reducing the number of lipophilic moieties in the biphenyl part of 1, using ClogD(7.4) values as the reference index of lipophilicity. This research led to the identification of N-{(3-exo)-8-[(6-fluoro-2-naphthyl)methyl]-8-azabicyclo[3.2.1]oct-3-yl}-3-(piperidin-1-ylcarbonyl)isonicotinamide 1-oxide (30) which showed comparable CCR3 inhibitory activity (IC(50)=23 nM) with much reduced CYP2D6 inhibitory activity (IC(50)=29,000 nM) compared with 1.
Assuntos
Inibidores do Citocromo P-450 CYP2D6 , Desenho de Fármacos , Hidrocarbonetos Fluorados/farmacologia , Naftalenos/farmacologia , Receptores CCR3/antagonistas & inibidores , Cálcio/química , Cálcio/metabolismo , Citoplasma/química , Citoplasma/metabolismo , Humanos , Hidrocarbonetos Fluorados/síntese química , Concentração Inibidora 50 , Naftalenos/síntese química , Receptores CCR3/metabolismo , Relação Estrutura-AtividadeRESUMO
Experimental colitis studies, including T cell-mediated colitis, indicate that IL-23 rather than IL-12 orchestrates intestinal inflammation in inflammatory bowel disease (IBD). Previous studies have identified the roles of IL-12 and IL-23 using mice deficient for their specific subunits, p35 and p19, respectively. However, these studies do not completely reflect the difference in roles between IL-12 and IL-23, especially since the discovery of novel IL-12 family cytokines, which also include p35 or p19 subunits. Here, to clarify the contribution of IL-12 and IL-23 in T cell-mediated colitis, we compared the efficacy of a monoclonal antibody (mAb) to an IL-23-specific receptor subunit with that of an anti-IL-12/23p40 mAb in a naive CD4+ T cell transfer model of experimental colitis, which is associated with enhanced Th1 and Th17 responses. Both antibodies almost completely prevented the development of colitis and showed reduced associated histological changes, including mucosal hyperplasia, infiltration of inflammatory cells and loss of goblet cells. The anti-IL-23 receptor mAb inhibited not only the systemic Th17-response but also the Th1-response, both of which were up-regulated in this model. These results suggest that IL-23, but not IL-12, signaling is critical for the development of colitis. Blockade of IL-23 signaling is a promising therapeutic approach for IBD.
Assuntos
Anticorpos Monoclonais/imunologia , Linfócitos T CD4-Positivos/imunologia , Colite/imunologia , Colite/prevenção & controle , Interleucina-23/imunologia , Células Th1/imunologia , Células Th17/imunologia , Animais , Anticorpos Monoclonais/sangue , Masculino , CamundongosRESUMO
B cell-mediated antibodies play a critical role in protecting the body from infections; however, excessive antibody production is involved in the pathogenesis of autoimmune diseases and transplanted organ rejection. Regulation of antibody production is therefore crucial for overcoming these complications. Phosphatidylinositol-3-kinase p110δ (PI3Kδ), a member of the family of PI3K lipid kinases, is a key mediator of B cell activation and proliferation, with a small molecule PI3Kδ inhibitor having been approved for the treatment of B cell lymphoma. However, the effect of PI3Kδ inhibitors on B cell-mediated antibody production has not been clearly elucidated. In this study, we investigated the effect of the selective PI3Kδ inhibitor, AS2541019, on B cell immunity and antibody production. Our results show that AS2541019 effectively prevented B cell activation and proliferation in vitro, and that oral administration of AS2541019 resulted in significant inhibition of both T-dependent and T-independent de novo antibody production in peripheral blood. Further, in a hamster to rat concordant xenotransplant model, AS2541019 significantly prolonged graft survival time by inhibiting xenoreactive antibody production. Therefore, our study demonstrates that the selective PI3Kδ inhibitor AS2541019 inhibits antibody production through potent inhibitory effects on B cell activation, and can protect against organ dysfunction.
Assuntos
Formação de Anticorpos/efeitos dos fármacos , Classe I de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Rejeição de Enxerto/prevenção & controle , Ativação Linfocitária/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cricetinae , Feminino , Rejeição de Enxerto/imunologia , Xenoenxertos/efeitos dos fármacos , Xenoenxertos/imunologia , Humanos , Leucócitos Mononucleares , Masculino , Mesocricetus , Modelos Animais , Transplante de Órgãos/efeitos adversos , Inibidores de Proteínas Quinases/uso terapêutico , Ratos , Ratos Endogâmicos Lew , Transplante Heterólogo/efeitos adversosRESUMO
BACKGROUND: Janus kinase (JAK) inhibitors are thought to be promising candidates to aid renal transplantation. However, the effectiveness of JAK inhibitors against features of chronic rejection, including interstitial fibrosis/tubular atrophy (IF/TA) and glomerulosclerosis, has not been elucidated. Here, we investigated the effect of AS2553627, a novel JAK inhibitor, on the development of chronic rejection in rat renal transplantation. METHODS: Lewis (LEW) to Brown Norway (BN) rat renal transplantation was performed. Tacrolimus (TAC) at 0.1mg/kg was administered intramuscularly once a day for 10 consecutive days starting on the day of transplantation (days 0 to 9) to prevent initial acute rejection. After discontinuation of TAC treatment from days 10 to 28, AS2553627 (1 and 10mg/kg) was orally administered with TAC. At 13weeks after renal transplantation, grafts were harvested for histopathological and mRNA analysis. Creatinine and donor-specific antibodies were measured from plasma samples. Urinary protein and kidney injury markers were also evaluated. RESULTS: AS2553627 in combination with TAC exhibited low plasma creatinine and a marked decrease in urinary protein and kidney injury markers, such as tissue inhibitor of metalloproteinase-1 and kidney injury molecule-1. At 13weeks, histopathological analysis revealed that AS2553627 treatment inhibited glomerulosclerosis and IF/TA. In addition, upregulation of cell surface markers, fibrosis/epithelial-mesenchymal transition and inflammation-related genes were reduced by the combination of AS2553672 and TAC, particularly CD8 and IL-6 mRNAs, indicating that AS2553627 prevented cell infiltration and inflammation in renal allografts. CONCLUSIONS: These results indicate the therapeutic potential of JAK inhibitors in chronic rejection progression, and suggest that AS2553627 is a promising agent to improve long-term graft survival after renal transplantation.
Assuntos
Aloenxertos/imunologia , Glomerulosclerose Segmentar e Focal/prevenção & controle , Rejeição de Enxerto/prevenção & controle , Transplante de Rim , Piperidinas/uso terapêutico , Pirróis/uso terapêutico , Animais , Doença Crônica , Modelos Animais de Doenças , Quimioterapia Combinada , Glomerulosclerose Segmentar e Focal/imunologia , Rejeição de Enxerto/imunologia , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Janus Quinases/antagonistas & inibidores , Ratos , Ratos Endogâmicos Lew , Tacrolimo/uso terapêuticoRESUMO
Interleukin (IL)-12 and IL-23 share a common subunit (p40) and function in T-helper (Th) 1 and Th17 immunity, respectively. Anti-IL-12/23p40 and specific anti-IL-23 antibodies are currently in clinical use for psoriasis and undergoing trials for autoimmune diseases. Since expression levels of the IL-23 receptor are likely to be much lower than those of IL-23, an anti-IL-23 receptor antibody might offer greater promise in inhibiting the IL-23-IL-17 pathways involved in inflammatory disorders. To our knowledge, no anti-IL-23 receptor antibody has been trialed in clinical studies to date. This study describes the generation and characterization of AS2762900-00, a fully human monoclonal antibody against the IL-23 receptor. AS2762900-00 bound both human and cynomolgus monkey IL-23 receptors. AS2762900-00 showed potent inhibitory effects on IL-23-induced Kit-225 cell proliferation compared to the existing anti-IL-12/23p40 antibody, ustekinumab. In a single dose administration pharmacodynamics study in cynomolgus monkeys, 1â¯mg/kg of AS2762900-00 significantly inhibited (> 85%) IL-23-induced STAT3 phosphorylation in blood for up to 84 days. Therefore, AS2762900-00 represents a potent novel IL-23-IL-17 pathway inhibitor with the potential to be developed into a new therapy for the treatment of autoimmune diseases.
Assuntos
Anticorpos Monoclonais/imunologia , Receptores de Interleucina/imunologia , Animais , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Interleucina-23/farmacologia , Macaca fascicularis , MasculinoRESUMO
In renal transplant patients, using mycophenolate mofetil (MMF) with calcineurin inhibitors (CNIs; cyclosporine and tacrolimus [TAC]) has led to a significant improvement in graft survival. However, reducing or withholding MMF due to its gastrointestinal adverse events increases rejection risk. CNI-sparing strategies are important to avoid CNI-related nephrotoxicity in clinical settings. Here, we investigated AS2553627, a JAK inhibitor replacing MMF in combination with a sub-therapeutic dose of TAC to treat allograft rejection in a monkey model. AS2553627 inhibited proliferation of IL-2 stimulated T cells with little species difference between monkeys and humans. In MMF monotherapy, oral administration of 20 or 40â¯mg/kg/day prolonged graft survival with median survival times (MSTs) of 16.5â¯days and 33â¯days, respectively, whereas untreated animals showed MST of 6â¯days. In MMF/TAC (1â¯mg/kg/day, p.o.) combination therapy, pharmacokinetic analysis indicated that MMF 20â¯mg/kg/day achieved the clinical target AUC0-24h and prolonged renal allograft survival, with MST of 24â¯days. Oral administration of AS2553627 0.24â¯mg/kg/day in combination with TAC significantly prolonged renal allograft survival to MST of >90â¯days with low plasma creatinine levels. Histopathological analysis revealed that acute T cell-mediated rejection events such as vasculitis and interstitial mononuclear cell infiltration were significantly inhibited in AS2553627/TAC-treated allografts compared with MMF/TAC-treated allografts. All AS2553627/TAC-treated monkeys surviving >90â¯days exhibited less interstitial fibrosis/tubular atrophy than monkeys in the MMF/TAC group. These results suggest that AS2553627 replacing MMF is an attractive CNI-sparing strategy to prevent renal allograft rejection.
Assuntos
Rejeição de Enxerto/prevenção & controle , Imunossupressores/administração & dosagem , Transplante de Rim/efeitos adversos , Ácido Micofenólico/administração & dosagem , Piperidinas/administração & dosagem , Pirróis/administração & dosagem , Tacrolimo/administração & dosagem , Animais , Ativação Linfocitária/efeitos dos fármacos , Macaca fascicularis , Masculino , Transplante HomólogoRESUMO
Donor-specific antibodies (DSA) are a major risk factor for antibody-mediated rejection (ABMR) in solid organ transplantation, and ABMR remains a medical challenge. Therefore, effective anti-ABMR therapies are needed to improve overall graft survival. Cathepsin S (Cat S) is an essential protease for antigen peptide loading onto lysosomal/endosomal major histocompatibility complex (MHC) class II molecules to promote antigen presentation. Cat S deficiency produces immuno-deficient phenotypes including a suppressed humoral immune response, and Cat S inhibition reportedly prevents autoimmunity. However, little is known about the effects of Cat S inhibitors on organ transplantation, especially ABMR. Here, we report the pharmacological profile of novel Cat S inhibitors, AS2761325 and AS2863995, and explore their preventive potential on DSA production and acute rejection in a mouse cardiac transplantation model. Cat S inhibitors potently inhibited upregulation of antigen peptide loading MHC class II expression on the surface of splenic B cells and suppressed ovalbumin-induced T cell-dependent antibody production in mice. In a mouse cardiac transplantation model, oral administration of AS2761325 monotherapy inhibited DSA production without affecting graft survival. When combined with a suboptimal dose of tacrolimus, AS2761325 significantly prolonged graft survival. The more potent Cat S inhibitor AS2863995 also prolonged graft survival and almost completely suppressed DSA production. These results suggest that Cat S inhibitors may be promising ABMR prophylaxis drug candidates. Combination therapy comprising a Cat S inhibitor and calcineurin inhibitors may be a more effective immunosuppressive maintenance therapy for controlling both cell-mediated and antibody-mediated rejection.