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1.
BMJ Case Rep ; 17(5)2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38719260

RESUMO

The use of dulaglutide, a common medication for managing type 2 diabetes, rarely causes elevated pancreatic tumour markers. Here, we report the case of a woman in her mid-60s with diabetes for over 10 years. The patient presented with markedly elevated serum CA19-9 and CA242 levels revealed during a routine health examination despite being asymptomatic. She had been receiving dulaglutide injections for 16 months. Imaging and interventional assessments did not reveal any hepatobiliary, gastrointestinal or pancreatic neoplasm. After excluding alternate diagnoses, the patient was determined to exhibit an adverse reaction to dulaglutide use. Management involved the discontinuation of dulaglutide, which resulted in normalisation of serum CA19-9 and CA242 levels within 6 weeks. This case underscores the importance of discontinuing dulaglutide and monitoring changes in the biomarker levels in asymptomatic patients receiving dulaglutide, rather than immediately resorting to imaging and endoscopic examinations.


Assuntos
Antígeno CA-19-9 , Diabetes Mellitus Tipo 2 , Peptídeos Semelhantes ao Glucagon , Hipoglicemiantes , Fragmentos Fc das Imunoglobulinas , Proteínas Recombinantes de Fusão , Humanos , Proteínas Recombinantes de Fusão/efeitos adversos , Proteínas Recombinantes de Fusão/uso terapêutico , Proteínas Recombinantes de Fusão/administração & dosagem , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Peptídeos Semelhantes ao Glucagon/efeitos adversos , Peptídeos Semelhantes ao Glucagon/uso terapêutico , Feminino , Fragmentos Fc das Imunoglobulinas/efeitos adversos , Fragmentos Fc das Imunoglobulinas/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/sangue , Antígeno CA-19-9/sangue , Pessoa de Meia-Idade , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/sangue
2.
Reprod Biol Endocrinol ; 22(1): 52, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711160

RESUMO

BACKGROUND: Elevated FSH often occurs in women of advanced maternal age (AMA, age ≥ 35) and in infertility patients undergoing controlled ovarian stimulation (COS). There is controversy on whether high endogenous FSH contributes to infertility and whether high exogenous FSH adversely impacts patient pregnancy rates. METHODS: The senescence-accelerated mouse-prone-8 (SAMP8) model of female reproductive aging was employed to assess the separate impacts of age and high FSH activity on the percentages (%) of viable and mature ovulated oocytes recovered after gonadotropin treatment. Young and midlife mice were treated with the FSH analog equine chorionic gonadotropin (eCG) to model both endogenous FSH elevation and exogenous FSH elevation. Previously we showed the activin inhibitor ActRIIB:Fc increases oocyte quality by preventing chromosome and spindle misalignments. Therefore, ActRIIB:Fc treatment was performed in an effort to increase % oocyte viability and % oocyte maturation. RESULTS: The high FSH activity of eCG is ootoxic to ovulatory oocytes, with greater decreases in % viable oocytes in midlife than young mice. High FSH activity of eCG potently inhibits oocyte maturation, decreasing the % of mature oocytes to similar degrees in young and midlife mice. ActRIIB:Fc treatment does not prevent eCG ootoxicity, but it restores most oocyte maturation impeded by eCG. CONCLUSIONS: FSH ootoxicity to ovulatory oocytes and FSH maturation inhibition pose a paradox given the well-known pro-growth and pro-maturation activities of FSH in the earlier stages of oocyte growth. We propose the FOOT Hypothesis ("FSH OoToxicity Hypothesis), that FSH ootoxicity to ovulatory oocytes comprises a new driver of infertility and low pregnancy success rates in DOR women attempting spontaneous pregnancy and in COS/IUI patients, especially AMA women. We speculate that endogenous FSH elevation also contributes to reduced fecundity in these DOR and COS/IUI patients. Restoration of oocyte maturation by ActRIB:Fc suggests that activin suppresses oocyte maturation in vivo. This contrasts with prior studies showing activin A promotes oocyte maturation in vitro. Improved oocyte maturation with agents that decrease endogenous activin activity with high specificity may have therapeutic benefit for COS/IVF patients, COS/IUI patients, and DOR patients attempting spontaneous pregnancies.


Assuntos
Receptores de Activinas Tipo II , Oócitos , Animais , Feminino , Oócitos/efeitos dos fármacos , Camundongos , Receptores de Activinas Tipo II/metabolismo , Ovulação/efeitos dos fármacos , Gonadotropina Coriônica/farmacologia , Hormônio Foliculoestimulante/sangue , Oogênese/efeitos dos fármacos , Indução da Ovulação/métodos , Fragmentos Fc das Imunoglobulinas/farmacologia , Envelhecimento/efeitos dos fármacos , Envelhecimento/fisiologia , Gravidez , Ativinas
3.
PLoS One ; 19(4): e0300964, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38557973

RESUMO

Human immunoglobulin G (IgG) exists as four subclasses IgG1-4, each of which has two Fab subunits joined by two hinges to a Fc subunit. IgG4 has the shortest hinge with 12 residues. The Fc subunit has two glycan chains, but the importance of glycosylation is not fully understood in IgG4. Here, to evaluate the stability and structure of non-glycosylated IgG4, we performed a multidisciplinary structural study of glycosylated and deglycosylated human IgG4 A33 for comparison with our similar study of human IgG1 A33. After deglycosylation, IgG4 was found to be monomeric by analytical ultracentrifugation; its sedimentation coefficient of 6.52 S was reduced by 0.27 S in reflection of its lower mass. X-ray and neutron solution scattering showed that the overall Guinier radius of gyration RG and its cross-sectional values after deglycosylation were almost unchanged. In the P(r) distance distribution curves, the two M1 and M2 peaks that monitor the two most common distances within IgG4 were unchanged following deglycosylation. Further insight from Monte Carlo simulations for glycosylated and deglycosylated IgG4 came from 111,382 and 117,135 possible structures respectively. Their comparison to the X-ray and neutron scattering curves identified several hundred best-fit models for both forms of IgG4. Principal component analyses showed that glycosylated and deglycosylated IgG4 exhibited different conformations from each other. Within the constraint of unchanged RG and M1-M2 values, the glycosylated IgG4 models showed more restricted Fc conformations compared to deglycosylated IgG4, but no other changes. Kratky plots supported this interpretation of greater disorder upon deglycosylation, also observed in IgG1. Overall, these more variable Fc conformations may demonstrate a generalisable impact of deglycosylation on Fc structures, but with no large conformational changes in IgG4 unlike those seen in IgG1.


Assuntos
Fragmentos Fc das Imunoglobulinas , Imunoglobulina G , Humanos , Imunoglobulina G/química , Estudos Transversais , Modelos Moleculares , Fragmentos Fc das Imunoglobulinas/química
4.
J Med Virol ; 96(5): e29638, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38682662

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has caused more than 676 million cases in the global human population with approximately 7 million deaths and vaccination has been proved as the most effective countermeasure in reducing clinical complications and mortality rate of SARS-CoV-2 infection in people. However, the protective elements and correlation of protection induced by vaccination are still not completely understood. Various antibodies with multiple protective mechanisms can be induced simultaneously by vaccination in vivo, thereby complicating the identification and characterization of individual correlate of protection. Recently, an increasing body of observations suggests that antibody-induced Fc-effector functions play a crucial role in combating SARS-CoV-2 infections, including neutralizing antibodies-escaping variants. Here, we review the recent progress in understanding the impact of Fc-effector functions in broadly disarming SARS-CoV-2 infectivity and discuss various efforts in harnessing this conserved antibody function to develop an effective SARS-CoV-2 vaccine that can protect humans against infections by SARS-CoV-2 virus and its variants of concern.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , Fragmentos Fc das Imunoglobulinas , SARS-CoV-2 , Humanos , SARS-CoV-2/imunologia , Anticorpos Neutralizantes/imunologia , COVID-19/prevenção & controle , COVID-19/imunologia , Anticorpos Antivirais/imunologia , Vacinas contra COVID-19/imunologia , Fragmentos Fc das Imunoglobulinas/imunologia , Animais , Vacinação
5.
Clin Transl Sci ; 17(4): e13775, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38651744

RESUMO

This study aimed to evaluate the pharmacokinetics (PKs), safety, and immunogenicity of the biosimilar HEC14028 compared to reference Trulicity® (dulaglutide) in healthy male Chinese subjects. This study was a single-center, randomized, open, single-dose, parallel-controlled comparative Phase I clinical trial, including a screening period of up to 14 days, a 17-day observation period after administration, and a 7-day safety follow-up period. A total of 68 healthy male subjects were randomly assigned (1:1) to the test group (HEC14028) and the reference group (dulaglutide) (single 0.75 mg abdominal subcutaneous dose). The primary objective was to evaluate the pharmacokinetic characteristics of HEC14028 and compare the pharmacokinetic similarities between HEC14028 and dulaglutide. The primary PK endpoints were maximum plasma concentration (Cmax) and area under the blood concentration-time curve from zero time to the estimated infinite time (AUC0-∞). The study results showed that HEC14028 and dulaglutide were pharmacokinetically equivalent: 90% confidence interval (CI) of Cmax and AUC0-∞ geometric mean ratios were 102.9%-122.0% and 97.1%-116.9%, respectively, which were both within the range of 80.00%-125.00%. No grade 3 or above treatment emergent adverse events (TEAEs), serious adverse events (SAEs), TEAEs leading to withdrawal from the trial, or TEAEs leading to death were reported in this study. Both HEC14028 and dulaglutide showed good and similar safety profiles, and no incremental immunogenicity was observed in subjects receiving HEC14028 and dulaglutide.


Assuntos
Medicamentos Biossimilares , Peptídeos Semelhantes ao Glucagon , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Voluntários Saudáveis , Fragmentos Fc das Imunoglobulinas , Proteínas Recombinantes de Fusão , Humanos , Masculino , Fragmentos Fc das Imunoglobulinas/administração & dosagem , Fragmentos Fc das Imunoglobulinas/efeitos adversos , Fragmentos Fc das Imunoglobulinas/imunologia , Peptídeos Semelhantes ao Glucagon/farmacocinética , Peptídeos Semelhantes ao Glucagon/administração & dosagem , Peptídeos Semelhantes ao Glucagon/efeitos adversos , Proteínas Recombinantes de Fusão/farmacocinética , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/efeitos adversos , Medicamentos Biossimilares/farmacocinética , Medicamentos Biossimilares/administração & dosagem , Medicamentos Biossimilares/efeitos adversos , Adulto , Adulto Jovem , China , Área Sob a Curva , Povo Asiático , Equivalência Terapêutica , Injeções Subcutâneas , Hipoglicemiantes/farmacocinética , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/efeitos adversos , Pessoa de Meia-Idade , Adolescente , População do Leste Asiático
6.
Nat Commun ; 15(1): 3600, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38678029

RESUMO

Streptococcus pyogenes can cause invasive disease with high mortality despite adequate antibiotic treatments. To address this unmet need, we have previously generated an opsonic IgG1 monoclonal antibody, Ab25, targeting the bacterial M protein. Here, we engineer the IgG2-4 subclasses of Ab25. Despite having reduced binding, the IgG3 version promotes stronger phagocytosis of bacteria. Using atomic simulations, we show that IgG3's Fc tail has extensive movement in 3D space due to its extended hinge region, possibly facilitating interactions with immune cells. We replaced the hinge of IgG1 with four different IgG3-hinge segment subclasses, IgGhxx. Hinge-engineering does not diminish binding as with IgG3 but enhances opsonic function, where a 47 amino acid hinge is comparable to IgG3 in function. IgGh47 shows improved protection against S. pyogenes in a systemic infection mouse model, suggesting that IgGh47 has promise as a preclinical therapeutic candidate. Importantly, the enhanced opsonic function of IgGh47 is generalizable to diverse S. pyogenes strains from clinical isolates. We generated IgGh47 versions of anti-SARS-CoV-2 mAbs to broaden the biological applicability, and these also exhibit strongly enhanced opsonic function compared to the IgG1 subclass. The improved function of the IgGh47 subclass in two distant biological systems provides new insights into antibody function.


Assuntos
Anticorpos Antivirais , COVID-19 , Fragmentos Fc das Imunoglobulinas , Imunoglobulina G , SARS-CoV-2 , Streptococcus pyogenes , Animais , Imunoglobulina G/imunologia , Streptococcus pyogenes/imunologia , SARS-CoV-2/imunologia , Camundongos , Humanos , Anticorpos Antivirais/imunologia , COVID-19/imunologia , COVID-19/virologia , Fragmentos Fc das Imunoglobulinas/imunologia , Fragmentos Fc das Imunoglobulinas/genética , Fragmentos Fc das Imunoglobulinas/química , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/microbiologia , Anticorpos Monoclonais/imunologia , Anticorpos Antibacterianos/imunologia , Fagocitose , Feminino , Engenharia de Proteínas/métodos , Camundongos Endogâmicos BALB C
7.
Front Immunol ; 15: 1341013, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38655263

RESUMO

Recombinant Factor VIII-Fc fusion protein (rFVIIIFc) is an enhanced half-life therapeutic protein product used for the management of hemophilia A. Recent studies have demonstrated that rFVIIIFc interacts with Fc gamma receptors (FcγR) resulting in the activation or inhibition of various FcγR-expressing immune cells. We previously demonstrated that rFVIIIFc, unlike recombinant Factor IX-Fc (rFIXFc), activates natural killer (NK) cells via Fc-mediated interactions with FcγRIIIA (CD16). Additionally, we showed that rFVIIIFc activated CD16+ NK cells to lyse a FVIII-specific B cell clone. Here, we used human NK cell lines and primary NK cells enriched from peripheral blood leukocytes to study the role of the FVIII moiety in rFVIIIFc-mediated NK cell activation. Following overnight incubation of NK cells with rFVIIIFc, cellular activation was assessed by measuring secretion of the inflammatory cytokine IFNγ by ELISA or by cellular degranulation. We show that anti-FVIII, anti-Fc, and anti-CD16 all inhibited indicating that these molecules were involved in rFVIIIFc-mediated NK cell activation. To define which domains of FVIII were involved, we used antibodies that are FVIII domain-specific and demonstrated that blocking FVIII C1 or C2 domain-mediated membrane binding potently inhibited rFVIIIFc-mediated CD16+ NK cell activation, while targeting the FVIII heavy chain domains did not. We also show that rFVIIIFc binds CD16 with about five-fold higher affinity than rFIXFc. Based on our results we propose that FVIII light chain-mediated membrane binding results in tethering of the fusion protein to the cell surface, and this, together with increased binding affinity for CD16, allows for Fc-CD16 interactions to proceed, resulting in NK cellular activation. Our working model may explain our previous results where we observed that rFVIIIFc activated NK cells via CD16, whereas rFIXFc did not despite having identical IgG1 Fc domains.


Assuntos
Fator VIII , Proteínas Ligadas por GPI , Fragmentos Fc das Imunoglobulinas , Células Matadoras Naturais , Ativação Linfocitária , Receptores de IgG , Proteínas Recombinantes de Fusão , Humanos , Degranulação Celular/imunologia , Fator VIII/química , Fator VIII/imunologia , Proteínas Ligadas por GPI/imunologia , Proteínas Ligadas por GPI/metabolismo , Hemofilia A/imunologia , Hemofilia A/tratamento farmacológico , Fragmentos Fc das Imunoglobulinas/imunologia , Interferon gama/metabolismo , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Ativação Linfocitária/imunologia , Ativação Linfocitária/efeitos dos fármacos , Ligação Proteica , Receptores de IgG/metabolismo , Receptores de IgG/imunologia
8.
Expert Opin Biol Ther ; 24(4): 233-241, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38555469

RESUMO

INTRODUCTION: In patients with myelodysplastic syndromes (MDS), anemia is prevalent affecting 80%-85% of low-risk (LR-MDS) patients, with 40% eventually requiring red blood cell (RBC) transfusions. Except forlenalidomide, exclusively approved for those with deletion of chromosome 5q,erythropoiesis-stimulating agents (ESAs) are the primary treatment choice for low-risk patients. Those unresponsive to ESAs face limited alternatives, eventually necessitating long-term RBC transfusions, leading to secondary iron overload and adversely affecting quality of life (QoL). AREA COVERED: Luspatercept is a pioneering erythroid maturation agent. It received approval by both the European Medicines Agency (EMA) and the Food and Drug Administration (FDA) for treating adults experiencing transfusion-dependent anemia associated with LR-MDS or ß-thalassemia. Recently, the FDA approved luspatercept as first- line therapy in patients with very low- to intermediate-risk MDS who require RBC transfusions and have not previously received ESAs. This review summarizes the historical impact of luspatercept intreating LR-MDS unresponsive to ESAs and illustrates its potential benefit asfrontline therapy in MDS and its employment in patients with myelofibrosis-induced anemia. EXPERT OPINION: Luspatercept has revolutionized the therapeutic paradigm of LR-MDS, for which there was a limited therapeutic arsenal, especially in the setting of patients who did not respond or fail after ESA treatment.


Assuntos
Receptores de Activinas Tipo II , Hematínicos , Fragmentos Fc das Imunoglobulinas , Síndromes Mielodisplásicas , Proteínas Recombinantes de Fusão , Humanos , Síndromes Mielodisplásicas/tratamento farmacológico , Fragmentos Fc das Imunoglobulinas/uso terapêutico , Fragmentos Fc das Imunoglobulinas/efeitos adversos , Hematínicos/uso terapêutico , Hematínicos/efeitos adversos , Proteínas Recombinantes de Fusão/uso terapêutico , Proteínas Recombinantes de Fusão/efeitos adversos , Receptores de Activinas Tipo II/uso terapêutico , Anemia/tratamento farmacológico , Transfusão de Eritrócitos , Qualidade de Vida
9.
Biomed Pharmacother ; 174: 116485, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38518602

RESUMO

BACKGROUND: Glucagon-like peptide-1 (GLP-1)/glucagon (GCG) dual receptor agonists with different receptor selectivity are under investigation and have shown significant improvement in both weight loss and glycemic control, but the optimal potency ratio between the two receptors to balance efficacy and safety remains unclear. EXPERIMENTAL APPROACH: We designed and constructed several dual receptor agonists with different receptor potency ratios using Fc fusion protein technology. The long-term effects of the candidates on body weight and metabolic dysfunction-associated steatotic liver disease (MASLD) were evaluated in diet-induced obese (DIO) model mice, high-fat diet (HFD)-ob/ob mice and AMLN diet-induced MASLD mice. Repeat dose toxicity assays were performed to investigate the safety profile of the candidate (HEC-C070) in Sprague Dawley (SD) rats. KEY RESULTS: The high GCG receptor (GCGR) selectivity of HEC-C046 makes it more prominent than other compounds for weight loss and most MASLD parameters but may lead to safety concerns. The weight change of HEC-C052 with the lowest GCG agonism was inferior to that of selective GLP-1 receptor agonist (GLP-1RA) semaglutide in DIO model mice. The GLP-1R selectivity of HEC-C070 with moderate GCG agonism has a significant effect on weight loss and liver function in obese mice, and its lowest observed adverse effect level (LOAEL) was 30 nmol/kg in the repeat dose toxicity study. CONCLUSION: We compared the potential of the Fc fusion protein GLP-1/GCG dual receptor agonists with different receptor selectivity to provide the setting for future GLP-1/GCG dual receptor agonists to treat obesity and MASLD.


Assuntos
Dieta Hiperlipídica , Peptídeo 1 Semelhante ao Glucagon , Receptor do Peptídeo Semelhante ao Glucagon 1 , Fragmentos Fc das Imunoglobulinas , Obesidade , Receptores de Glucagon , Proteínas Recombinantes de Fusão , Animais , Humanos , Camundongos , Ratos , Dieta Hiperlipídica/efeitos adversos , Peptídeo 1 Semelhante ao Glucagon/agonistas , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Peptídeos Semelhantes ao Glucagon/farmacologia , Fragmentos Fc das Imunoglobulinas/farmacologia , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Ratos Sprague-Dawley , Receptores de Glucagon/agonistas , Receptores de Glucagon/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Redução de Peso/efeitos dos fármacos
10.
J Pharm Biomed Anal ; 244: 116120, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38547650

RESUMO

Charge heterogeneity is inherent to all therapeutic antibodies and arises from post-translational modifications (PTMs) and/or protein degradation events that may occur during manufacturing. Among therapeutic antibodies, the bispecific antibody (bsAb) containing two unique Fab arms directed against two different targets presents an additional layer of complexity to the charge profile. In the context of a bsAb, a single domain-specific PTM within one of the Fab domains may be sufficient to compromise target binding and could potentially impact the stability, safety, potency, and efficacy of the drug product. Therefore, characterization and routine monitoring of domain-specific modifications is critical to ensure the quality of therapeutic bispecific antibody products. We developed a Digestion-assisted imaged Capillary isoElectric focusing (DiCE) method to detect and quantitate domain-specific charge variants of therapeutic bispecific antibodies (bsAbs). The method involves enzymatic digestion using immunoglobulin G (IgG)-degrading enzyme of S. pyogenes (IdeS) to generate F(ab)2 and Fc fragments, followed by imaged capillary isoelectric focusing (icIEF) under reduced, denaturing conditions to separate the light chains (LCs) from the Fd domains. Our results suggest that DiCE is a highly sensitive method that is capable of quantitating domain-specific PTMs of a bsAb. In one case study, DiCE was used to quantitate unprocessed C-terminal lysine and site-specific glycation of Lys98 in the complementarity-determining region (CDR) of a bsAb that could not be accurately quantitated using conventional, platform-based charge variant analysis, such as intact icIEF. Quantitation of these PTMs by DiCE was comparable to results from peptide mapping, demonstrating that DiCE is a valuable orthogonal method for ensuring product quality. This method may also have potential applications for characterizing fusion proteins, antibody-drug conjugates, and co-formulated antibody cocktails.


Assuntos
Anticorpos Biespecíficos , Focalização Isoelétrica , Processamento de Proteína Pós-Traducional , Anticorpos Biespecíficos/imunologia , Focalização Isoelétrica/métodos , Fragmentos Fab das Imunoglobulinas/imunologia , Fragmentos Fab das Imunoglobulinas/química , Humanos , Imunoglobulina G/imunologia , Fragmentos Fc das Imunoglobulinas/química
12.
Biochemistry ; 63(8): 958-968, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38426700

RESUMO

Bispecific antibodies (BsAbs) are undergoing continued development for applications in oncology and autoimmune diseases. While increasing activity by having more than one targeting arm, most BsAb engineering employs single Fc engagement as monoclonal antibodies. Here, we designed a novel immunoglobulin gamma-1 (IgG1)-derived dual-Fc BsAb containing two Fc regions and two distinct asymmetric antigen binding arms comprising a Fab arm and another VHH domain. In conjunction with the knob-into-hole technology, dual-Fc BsAbs could be produced with a high yield and good stability. We explore how Fc engineering effects on dual-Fc constructs could boost the desired therapeutic efficacy. This new format enabled simultaneous bispecific binding to corresponding antigens. Furthermore, compared to the one-Fc control molecules, dual-Fc BsAbs were shown to increase the avidity-based binding to FcγRs to result in higher ADCC and ADCP activities by potent avidity via binding to two antigens and Fc receptors. Overall, this novel BsAb format with enhanced effector functionalities provides a new option for antibody-based immunotherapy.


Assuntos
Anticorpos Biespecíficos , Anticorpos Biespecíficos/química , Fragmentos Fc das Imunoglobulinas/genética , Anticorpos Monoclonais
13.
Brain Behav ; 14(3): e3448, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38444330

RESUMO

INTRODUCTION: Treatment strategies for depression based on interventions for glucose and lipid metabolism disorders are receiving increasing attention. Investigating the mechanism of their antidepressant effect and exploring new diagnostic and therapeutic biomarkers have attracted increasing attention. Dulaglutide, a long-acting GLP-1 receptor agonist, has been reported to alleviate cognitive deficits and neuronal damage. However, the antidepressant effect of dulaglutide and, especially, the underlying mechanism are still poorly understood. In this study, we aimed to explore the underlying biomarkers of depression and potential modulatory targets of dulaglutide in chronic mild stress (CMS) mice. METHODS: Sixty mice were randomly divided into a control group (CON group), a CMS+Vehicle group (CMS+Veh group), a CMS+0.3 mg/kg dulaglutide group (Low Dula group), and a CMS+0.6 mg/kg dulaglutide group (High Dula group). Numerous behavioral tests, mainly the open field test, forced swimming test, and tail suspension test, were applied to evaluate the potential effect of dulaglutide treatment on anxiety- and depression-like behaviors in mice exposed to chronic stress. Furthermore, a liquid chromatography-tandem mass spectrometry-based metabolomics approach was utilized to investigate the associated mechanisms of dulaglutide treatment. RESULTS: Three weeks of dulaglutide treatment significantly reversed depressive-like but not anxiety-like behaviors in mice exposed to chronic stress for 4 weeks. The results from the metabolomics analysis showed that a total of 20 differentially expressed metabolites were identified between the CON and CMS+Veh groups, and 46 metabolites were selected between the CMS+Veh and High Dula groups in the hippocampus of the mice. Comprehensive analysis indicated that lipid metabolism, amino acid metabolism, energy metabolism, and tryptophan metabolism were disrupted in model mice that experienced depression and underwent dulaglutide therapy. CONCLUSION: The antidepressant effects of dulaglutide in a CMS depression model were confirmed. We identified 64 different metabolites and four major pathways associated with metabolic pathophysiological processes. These primary data provide a new perspective for understanding the antidepressant-like effects of dulaglutide and may facilitate the use of dulaglutide as a potential therapeutic strategy for depression.


Assuntos
Antidepressivos , Depressão , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Fragmentos Fc das Imunoglobulinas , Proteínas Recombinantes de Fusão , Animais , Camundongos , Depressão/tratamento farmacológico , Homeostase , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Biomarcadores
14.
Sci Transl Med ; 16(737): eadh1988, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38446900

RESUMO

Despite the advances in cancer treatment achieved, for example, by the CD20 antibody rituximab, an urgent medical need remains to optimize the capacity of such antibodies to induce antibody-dependent cellular cytotoxicity (ADCC) that determines therapeutic efficacy. The cytokine IL-15 stimulates proliferation, activation, and cytolytic capacity of NK cells, but broad clinical use is prevented by short half-life, poor accumulation at the tumor site, and severe toxicity due to unspecific immune activation. We here report modified immunocytokines consisting of Fc-optimized CD19 and CD20 antibodies fused to an IL-15 moiety comprising an L45E-E46K double mutation (MIC+ format). The E46K mutation abrogated binding to IL-15Rα, thereby enabling substitution of physiological trans-presentation by target binding and thus conditional IL-15Rßγ stimulation, whereas the L45E mutation optimized IL-15Rßγ agonism and producibility. In vitro analysis of NK activation, anti-leukemia reactivity, and toxicity using autologous and allogeneic B cells confirmed target-dependent function of MIC+ constructs. Compared with Fc-optimized CD19 and CD20 antibodies, MIC+ constructs mediated superior target cell killing and NK cell proliferation. Mouse models using luciferase-expressing human NALM-6 lymphoma cells, patient acute lymphoblastic leukemia (ALL) cells, and murine EL-4 lymphoma cells transduced with human CD19/CD20 as targets and human and murine NK cells as effectors, respectively, confirmed superior and target-dependent anti-leukemic activity. In summary, MIC+ constructs combine the benefits of Fc-optimized antibodies and IL-15 cytokine activity and mediate superior NK cell immunity with potentially reduced side effects. They thus constitute a promising new immunotherapeutic approach shown here for B cell malignancies.


Assuntos
Interleucina-15 , Linfoma , Animais , Humanos , Camundongos , Proteínas Adaptadoras de Transdução de Sinal , Anticorpos , Antígenos CD19 , Citocinas , Fragmentos Fc das Imunoglobulinas
15.
Diabetes Obes Metab ; 26(6): 2209-2228, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38505997

RESUMO

AIM: The cardiovascular benefits provided by glucagon-like peptide-1 receptor agonists (GLP-1RAs) extend beyond weight reduction and glycaemic control. One possible mechanism may relate to blood pressure (BP) reduction. We aim to quantify the BP-lowering effects of GLP1-RAs. METHODS: A comprehensive database search for placebo-controlled randomized controlled trials on GLP-1RA treatment was conducted until December 2023. Data extraction and quality assessment were carried out, employing a robust statistical analysis using a random effects model to determine outcomes with a mean difference (MD) in mmHg and 95% confidence intervals (CIs). The primary endpoint was the mean difference in systolic BP (SBP) and diastolic BP. Subgroup analyses and meta-regressions were done to account for covariates. RESULTS: Compared with placebo, GLP-1RAs modestly reduced SBP [semaglutide: MD -3.40 (95% CI -4.22 to -2.59, p < .001); liraglutide: MD -2.61 (95% CI -3.48 to -1.74, p < .001); dulaglutide: MD -1.46 (95% CI -2.20 to -0.72, p < .001); and exenatide: MD -3.36 (95% CI -3.63 to -3.10, p < .001)]. This benefit consistently increased with longer treatment durations. Diastolic BP reduction was only significant in the exenatide group [MD -0.94 (95% CI -1.78 to -0.1), p = .03]. Among semaglutide cohorts, mean changes in glycated haemoglobin and mean changes in body mass index were directly associated with SBP reduction. CONCLUSION: Patients on GLP-1RA experienced modest SBP lowering compared with placebo. This observed effect was associated with weight/body mass index reduction and better glycaemic control, which suggests that BP-lowering is an indirect effect of GLP-1RA and unlikely to be responsible for the benefits.


Assuntos
Pressão Sanguínea , Diabetes Mellitus Tipo 2 , Receptor do Peptídeo Semelhante ao Glucagon 1 , Hipoglicemiantes , Humanos , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Pressão Sanguínea/efeitos dos fármacos , Hipoglicemiantes/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/sangue , Ensaios Clínicos Controlados Aleatórios como Assunto , Liraglutida/uso terapêutico , Peptídeos Semelhantes ao Glucagon/uso terapêutico , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Exenatida/uso terapêutico , Exenatida/farmacologia , Fragmentos Fc das Imunoglobulinas/uso terapêutico , Proteínas Recombinantes de Fusão/uso terapêutico , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon
16.
Protein Expr Purif ; 218: 106449, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38423157

RESUMO

We previously showed that the root cause of low Protein A step yield observed for certain antibodies/Fc-fusions is the presence of non-binding aggregates in cell culture harvest. A pre-assumption for the above conclusion is that the aggregates, while do not bind to the preparative Protein A column, can bind to the analytical Protein A-high performance liquid chromatography (HPLC) column used for titer measurement. In the current work, using materials from a previous case with the low yield issue, we confirmed that non-binding aggregates in preparative Protein A flow-through can indeed bind to the analytical Protein A column. In addition, we showed that this discrepancy is mainly due to the different loading densities applied under these two circumstances. We also demonstrated that aggregate bound to the analytical Protein A column slightly stronger than the monomer, as it exhibited a longer retention time. In summary, the current study not only confirmed that non-binding aggregates detected in the preparative Protein A flow-through bind to the Protein A-HPLC column and contribute to the measured titer of culture harvest but also unravelled the reason for different binding behaviors exhibited by antibody aggregates towards preparative and analytical Protein A columns.


Assuntos
Anticorpos , Fragmentos Fc das Imunoglobulinas , Cromatografia Líquida de Alta Pressão/métodos , Espaço Extracelular
17.
Curr Med Res Opin ; 40(4): 567-574, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38407177

RESUMO

OBJECTIVE: To evaluate the efficacy endpoints of HbA1c and body weight loss after switching from the GLP-1 receptor agonists, semaglutide or dulaglutide, to treatment with the GIP/GLP-1 receptor agonist (RA) tirzepatide. METHODS: Models were developed and validated to describe the HbA1c and weight loss time course for semaglutide (SUSTAIN 1-10), dulaglutide (AWARD-11) and tirzepatide (SURPASS 1-5, phase 3 global T2D program). The impact of switching from once weekly GLP-1 RAs to tirzepatide was described by simulating the efficacy time course. Semaglutide and dulaglutide doses were escalated in accordance with their respective labels. RESULTS: Model-predicted mean decreases from baseline in HbA1c and body weight for semaglutide 0.5 mg, 1 mg, and 2 mg were 1.22 to 1.79% and 3.62 to 6.87 kg respectively, at Week 26. Model-predicted mean decreases from baseline in HbA1c and body weight for dulaglutide 1.5 mg, 3 mg and 4.5 mg were 1.53 to 1.84% and 2.55 to 3.71 kg respectively, at Week 26. After switching to tirzepatide 5, 10 and 15 mg HbA1c reductions were predicted to range between 1.95 to 2.46% and body weight reductions between 6.50 to 12.1 kg by Week 66. CONCLUSION: In this model-based simulation, switching from approved maintenance doses of semaglutide or dulaglutide to tirzepatide, even at the lowest approved maintenance dose of 5 mg, showed the potential to further improve HbA1c and body weight reductions.


Type 2 diabetes is a disease of elevated blood sugar levels. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are a type of medication used to treat type 2 diabetes that work on GLP-1 receptors in the body. Semaglutide and dulaglutide are examples of GLP-1 RAs, which lower blood sugar and body weight. Tirzepatide is a newer medication, which works on both GLP-1 and glucose-dependent insulinotropic polypeptide (GIP) receptors. It reduces blood sugar and body weight in people living with type 2 diabetes. Healthcare professionals and patients are interested in how switching medication from semaglutide or dulaglutide to tirzepatide might change blood glucose levels and body weight. However, because tirzepatide is a newer medication, there is not much information available on this aspect. Data from clinical trials of these medications were used to predict the effects of switching from semaglutide or dulaglutide to tirzepatide. These model-based simulations showed that switching to tirzepatide may further reduce HbA1c (a measure of blood sugar) and body weight. This may provide useful information to healthcare professionals and patients when making decisions about treatment with these medications.


Assuntos
Diabetes Mellitus Tipo 2 , Polipeptídeo Inibidor Gástrico , Receptor do Peptídeo Semelhante ao Glucagon 2 , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Hipoglicemiantes , Fragmentos Fc das Imunoglobulinas , Proteínas Recombinantes de Fusão , Humanos , Hipoglicemiantes/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hemoglobinas Glicadas , Peso Corporal , Redução de Peso , Peptídeo 1 Semelhante ao Glucagon , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas
18.
Clin Ther ; 46(3): 289-292, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38310052

RESUMO

PURPOSE: Glucagon-like peptide 1 receptor agonists (GLP1-RA) are effective therapies in lowering glycosylated hemoglobin (HbA1c), providing cardioprotective benefits, and lowering weight. The use of GLP1-RA solely for weight-loss has become commonplace in many practices, which in turn has made it difficult in some areas for those with type 2 diabetes (T2DM) to obtain these much-needed medications. METHODS: Using recent published literature, along with clinical experience, it has become apparent that many GLP1-RAs have become difficult to obtain for patients with diabetes. FINDINGS: Many clinicians started to prescribe the brand Ozempic® (semaglutide*) and dulaglutide for weight loss despite neither of them being Food and Drug Administration (FDA) approved for this indication. Ozempic, having outperformed dulaglutide in in both HbA1c reduction and weight loss, along with FDA approval of semaglutide for weight loss, has quickly become widely used off-label for weight loss. This off-label use may have increased, despite the approval of semaglutide,† because many insurances will not cover semaglutide solely for weight management. Most recently, Eli Lilly was able to develop tirzepatide,‡ which was FDA approved in May of 2022, and they are seeking fast-track FDA approval for weight loss and are projected to gain this approval within 2023. IMPLICATIONS: Insurance coverage for weight management remains sparse, and obtaining these therapies for diabetes has now become more burdensome, with insurance companies requiring a prior authorization proving FDA-approved diagnosis of T2DM. Hopefully, should more GLP1-Ras receive approval for weight loss, along with an increase in insurance coverage, the burden on patients with diabetes will be lessened as they are able to quickly obtain this highly effective therapy.


Assuntos
Diabetes Mellitus Tipo 2 , Polipeptídeo Inibidor Gástrico , Receptor do Peptídeo Semelhante ao Glucagon 2 , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Fragmentos Fc das Imunoglobulinas , Proteínas Recombinantes de Fusão , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Peptídeos Semelhantes ao Glucagon/efeitos adversos , Redução de Peso , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas
19.
J Clin Invest ; 134(4)2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38357917

RESUMO

Immunoglobulin G (IgG) antibodies in the form of high-dose intravenous immunoglobulin (IVIG) exert immunomodulatory activity and are used in this capacity to treat inflammatory and autoimmune diseases. Reductionist approaches have revealed that terminal sialylation of the single asparagine-linked (N-linked) glycan at position 297 of the IgG1 Fc bestows antiinflammatory activity, which can be recapitulated by introduction of an F241A point mutation in the IgG1 Fc (FcF241A). Here, we examined the antiinflammatory activity of CHO-K1 cell-produced FcF241A in vivo in models of autoimmune inflammation and found it to be independent of sialylation. Intriguingly, sialylation markedly improved the half-life and bioavailability of FcF241A via impaired interaction with the asialoglycoprotein receptor ASGPR. Further, FcF241A suppressed inflammation through the same molecular pathways as IVIG and sialylated IgG1 Fc and required the C-type lectin SIGN-R1 in vivo. This contrasted with FcAbdeg (efgartigimod), an engineered IgG1 Fc with enhanced neonatal Fc receptor (FcRn) binding, which reduced total serum IgG concentrations, independent of SIGN-R1. When coadministered, FcF241A and FcAbdeg exhibited combinatorial antiinflammatory activity. Together, these results demonstrated that the antiinflammatory activity of FcF241A requires SIGN-R1, similarly to that of high-dose IVIG and sialylated IgG1, and can be used in combination with other antiinflammatory therapeutics that rely on divergent pathways, including FcAbdeg.


Assuntos
Imunoglobulina G , Imunoglobulinas Intravenosas , Recém-Nascido , Humanos , Imunoglobulina G/genética , Imunoglobulina G/farmacologia , Imunoglobulinas Intravenosas/uso terapêutico , Fragmentos Fc das Imunoglobulinas/genética , Fragmentos Fc das Imunoglobulinas/farmacologia , Inflamação/genética , Inflamação/tratamento farmacológico , Receptores Fc/genética , Glicosilação
20.
Aust J Gen Pract ; 53(1-2): 57-61, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38316483

RESUMO

METHOD: A retrospective analysis was performed of actual and predicted (Holt-Winters modelling) semaglutide and dulaglutide prescriptions supplied by the Australian PBS and Repatriation PBS in 2021-22. RESULTS: Semaglutide prescriptions decreased by 17% in March - September 2022, whereas dulaglutide prescriptions increased by 53% in April - July 2022 before decreasing by 17% in August - September 2022. There were 119,069 fewer semaglutide and 31,953 more dulaglutide prescriptions supplied than predicted in April - July and June - July 2022, respectively. DISCUSSION: Changes in semaglutide and dulaglutide T2D prescription patterns in 2022 coincided with supply shortages. General practitioners are encouraged to continue to prescribe semaglutide and dulaglutide for their appropriate indication and support patients with alternative treatments during the shortage.


Assuntos
Diabetes Mellitus Tipo 2 , Prescrições de Medicamentos , Hipoglicemiantes , Humanos , Austrália , Diabetes Mellitus Tipo 2/tratamento farmacológico , Prescrições de Medicamentos/estatística & dados numéricos , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Hipoglicemiantes/provisão & distribuição , Hipoglicemiantes/uso terapêutico , Fragmentos Fc das Imunoglobulinas , Proteínas Recombinantes de Fusão , Estudos Retrospectivos
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