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1.
Chronic Obstr Pulm Dis ; 11(1): 3-12, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-37676644

RESUMO

Background: Patients with alpha-1 antitrypsin deficiency (AATD) exhibit dysregulated inflammatory responses and a predilection for autoimmunity. While the adverse event (AE) profiles of COVID-19 vaccines in several chronic inflammatory conditions are now available, safety and tolerability data for patients with severe AATD have yet to be described. The feasibility of coadministering vaccines against COVID-19 and influenza in this population is similarly unclear. Methods: We conducted a prospective study of 170 patients with Pi*ZZ genotype AATD receiving their initial vaccination series with ChAdOx1 nCoV-19 (AstraZeneca). Patients were monitored clinically for AEs over the week that followed their first and second doses. In parallel, we conducted the same assessments in patients with Pi*MM genotype chronic obstructive pulmonary disease (COPD) (n=160) and Pi*MM individuals without lung disease (n=150). The Pi*ZZ cohort was subsequently followed through 2 consecutive mRNA-based booster vaccines (monovalent and bivalent BNT162b2, Pfizer/BioNTech). To assess the safety of combined vaccination against COVID-19 and influenza, the quadrivalent influenza vaccine was administered to participants attending for their second COVID-19 booster vaccination, either on the same day or following a 1-week interval. Results: Pi*ZZ AATD participants did not display increased AEs compared to Pi*MM COPD or Pi*MM non-lung disease controls. Although unexpected and serious vaccine-associated AEs did occur, the majority of AEs experienced across the 3 groups were mild and self-limiting. The AATD demographic at highest risk for AEs (especially systemic and prolonged AEs) was young females. No increase in AE risk was observed in patients with established emphysema, sonographic evidence of liver disease, or in those receiving intravenous augmentation therapy. AE incidence declined sharply following the initial vaccine series. Same-day coadministration of the COVID-19 mRNA bivalent booster vaccine and the annual influenza vaccine did not result in increased AEs compared to sequential vaccines 1 week apart. Conclusions: Despite their pro-inflammatory state, patients with severe AATD are not at increased risk of AEs or serious AEs compared to patients with nonhereditary COPD and patients without lung disease. Same-day coadministration of COVID-19 booster vaccines with the annual influenza vaccine is feasible, safe, and well-tolerated in this population.

2.
Am J Respir Crit Care Med ; 208(9): 964-974, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37624745

RESUMO

Rationale: Intravenous plasma-purified alpha-1 antitrypsin (IV-AAT) has been used as therapy for alpha-1 antitrypsin deficiency (AATD) since 1987. Previous trials (RAPID and RAPID-OLE) demonstrated efficacy in preserving computed tomography of lung density but no effect on FEV1. This observational study evaluated 615 people with severe AATD from three countries with socialized health care (Ireland, Switzerland, and Austria), where access to standard medical care was equal but access to IV-AAT was not. Objectives: To assess the real-world longitudinal effects of IV-AAT. Methods: Pulmonary function and mortality data were utilized to perform longitudinal analyses on registry participants with severe AATD. Measurements and Main Results: IV-AAT confers a survival benefit in severe AATD (P < 0.001). We uncovered two distinct AATD phenotypes based on an initial respiratory diagnosis: lung index and non-lung index. Lung indexes demonstrated a more rapid FEV1 decline between the ages of 20 and 50 and subsequently entered a plateau phase of minimal decline from 50 onward. Consequentially, IV-AAT had no effect on FEV1 decline, except in patients with a Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage 2 lung index. Conclusions: This real-world study demonstrates a survival advantage from IV-AAT. This improved survival is largely decoupled from FEV1 decline. The observation that patients with severe AATD fall into two major phenotypes has implications for clinical trial design where FEV1 is a primary endpoint. Recruits into trials are typically older lung indexes entering the plateau phase and, therefore, unlikely to show spirometric benefits. IV-AAT attenuates spirometric decline in lung indexes in GOLD stage 2, a spirometric group commonly outside current IV-AAT commencement recommendations.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Deficiência de alfa 1-Antitripsina , Adulto , Humanos , Pessoa de Meia-Idade , Adulto Jovem , alfa 1-Antitripsina/uso terapêutico , alfa 1-Antitripsina/genética , Deficiência de alfa 1-Antitripsina/complicações , Deficiência de alfa 1-Antitripsina/diagnóstico , Deficiência de alfa 1-Antitripsina/tratamento farmacológico , Pulmão , Fenótipo , Sistema de Registros
3.
Chronic Obstr Pulm Dis ; 9(2): 266-273, 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35403416

RESUMO

Patients with severe alpha-1 antitrypsin deficiency (AATD) are at increased risk for the development of chronic obstructive pulmonary disease (COPD), particularly if they smoke. This, coupled with their predilection for dysregulated inflammation and autoimmunity, makes affected individuals priority candidates for vaccination against coronavirus disease 2019 (COVID-19). To promote vaccine uptake effectively, an understanding of the factors motivating people to proceed with vaccination is essential. The attitudes of patients with AATD towards COVID-19 vaccination have yet to be described. We prospectively studied 170 Pi*ZZ genotype AATD patients, 150 patients with nonhereditary (Pi*MM genotype) COPD and 140 Pi*MM genotype individuals without lung disease receiving first-dose vaccination with ChAdOx1 nCoV-19 (AstraZeneca). Patient attitudes towards vaccination and motivations for getting vaccinated were assessed at the time of the vaccine being offered. Following completion of the 2-dose vaccine series, Pi*ZZ patients were then re-assessed regarding their attitudes towards booster vaccination. The most common primary motivation for accepting vaccination in Pi*ZZ participants ≥50 years old was a fear of illness or death from COVID-19. In contrast, Pi*ZZ patients <50 years most often cited a desire to socialize. The motivation pattern of younger Pi*ZZ AATD patients was similar to that of non-deficient individuals of comparable age, whereas older Pi*ZZ individuals were more closely aligned with Pi*MM COPD and differed from age-matched controls without lung disease. When considering booster vaccination, Pi*ZZ patients were increasingly motivated by a desire to reacquire social freedoms. A desire to reduce the risk of transmission was not a prominent consideration in any of the groups studied. The most commonly cited reason for booster hesitancy was a lack of incentive, given that no additional social freedoms were available to triple-vaccinated individuals compared to those who were double-vaccinated at the time. Taken together, these data may inform policymakers attempting to promote vaccine uptake among patients with AATD.

4.
Sci Signal ; 13(633)2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32457113

RESUMO

Although insulin-like growth factor 1 (IGF-1) signaling promotes tumor growth and cancer progression, therapies that target the IGF-1 receptor (IGF-1R) have shown poor clinical efficacy. To address IGF-1R activity in cancer cells and how it differs from that of the closely related insulin receptor (IR), we focused on two tyrosines in the IGF-1R C-terminal tail that are not present in the IR and are essential for IGF-1-mediated cancer cell survival, migration, and tumorigenic growth. We found that Tyr1250 and Tyr1251 (Tyr1250/1251) were autophosphorylated in a cell adhesion-dependent manner. To investigate the consequences of this phosphorylation, we generated phosphomimetic Y1250E/Y1251E (EE) and nonphosphorylatable Y1250F/Y1251F (FF) mutant forms of IGF-1R. Although fully competent in kinase activity and signaling, the EE mutant was more rapidly internalized and degraded than either the wild-type or FF receptor. IGF-1 promoted the accumulation of wild-type and EE IGF-1R within the Golgi apparatus, whereas the FF mutant remained at the plasma membrane. Golgi-associated IGF-1R signaling was a feature of migratory cancer cells, and Golgi disruption impaired IGF-1-induced signaling and cell migration. Upon the formation of new cell adhesions, IGF-1R transiently relocalized to the plasma membrane from the Golgi. Thus, phosphorylation at Tyr1250/1251 promoted IGF-1R translocation to and signaling from the Golgi to support an aggressive cancer phenotype. This process distinguishes IGF-1R from IR signaling and could contribute to the poor clinical efficacy of antibodies that target IGF-1R on the cell surface.


Assuntos
Movimento Celular , Complexo de Golgi , Proteínas de Neoplasias , Neoplasias , Receptor IGF Tipo 1 , Adesão Celular , Linhagem Celular Tumoral , Complexo de Golgi/química , Complexo de Golgi/genética , Complexo de Golgi/metabolismo , Humanos , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias/química , Neoplasias/genética , Neoplasias/metabolismo , Fosforilação , Receptor IGF Tipo 1/química , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Tirosina/química , Tirosina/genética , Tirosina/metabolismo
5.
J Virol Methods ; 224: 83-90, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26335961

RESUMO

Retroscreen (hVIVO) have developed an RSV human viral challenge model (hVCM) for testing the efficacy of novel antiviral therapies by monitoring changes in viral load and symptoms. The integrated cycler technology and Simplexa™ kits (Focus Diagnostics) currently provide fast, qualitative and sensitive diagnostic testing in hospitals and other healthcare facilities for patients with well-established respiratory illness. We have developed a novel use of qualitative integrated cycler PCR (qicPCR) technology to identify onset of RSV infection enabling an informed dosing clinical protocol in the RSV hVCM. We have validated qicPCR detection of RSV in spiked nasal wash aspirates and demonstrate that the qicPCR assay is 94% concordant with RSV plaque assay data in nasal wash samples from 53 RSV inoculated human volunteers in the hVCM. The use of qicPCR for informed dosing was successfully implemented in a recent clinical trial demonstrating efficacy of the RSV entry inhibitor GS-5806 in the hVCM (NCT01756482). Comparison of qicPCR positivity in relation to nasal wash viral load measured by both RT-qPCR and plaque assay shows that the therapeutic exposure was correctly initiated prior to onset and peak of RSV viral shedding and symptoms in the majority of volunteers.


Assuntos
Antivirais/administração & dosagem , Cavidade Nasal/virologia , Reação em Cadeia da Polimerase/métodos , Infecções por Vírus Respiratório Sincicial/diagnóstico , Vírus Sinciciais Respiratórios/isolamento & purificação , Carga Viral/métodos , Ensaios Clínicos como Assunto , Humanos , Infecções por Vírus Respiratório Sincicial/tratamento farmacológico , Infecções por Vírus Respiratório Sincicial/patologia , Infecções por Vírus Respiratório Sincicial/virologia
6.
J Biol Chem ; 287(33): 28180-94, 2012 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-22685298

RESUMO

Insulin-like growth factor I receptor (IGF-1R) signaling is essential for cell, organ, and animal growth. The C-terminal tail of the IGF-1R exhibits regulatory function, but the mechanism is unknown. Here, we show that mutation of Ser-1248 (S1248A) enhances IGF-1R in vitro kinase activity, autophosphorylation, Akt/mammalian target of rapamycin activity, and cell growth. Ser-1248 phosphorylation is mediated by GSK-3ß in a mechanism that involves a priming phosphorylation on Ser-1252. GSK-3ß knock-out cells exhibit reduced IGF-1R cell surface expression, enhanced IGF-1R kinase activity, and signaling. Examination of crystallographic structures of the IGF-1R kinase domain revealed that the (1248)SFYYS(1252) motif adopts a conformation tightly packed against the kinase C-lobe when Ser-1248 is in the unphosphorylated state that favors kinase activity. S1248A mutation is predicted to lock the motif in this position. In contrast, phosphorylation of Ser-1248 will drive profound structural transition of the sequence, critically affecting connection of the C terminus as well as exposing potential protein docking sites. Decreased kinase activity of a phosphomimetic S1248E mutant and enhanced kinase activity in mutants of its predicted target residue Lys-1081 support this auto-inhibitory model. Thus, the SFYYS motif controls the organization of the IGF-1R C terminus relative to the kinase domain. Its phosphorylation by GSK-3ß restrains kinase activity and regulates receptor trafficking and signaling.


Assuntos
Receptor IGF Tipo 1/metabolismo , Transdução de Sinais , Motivos de Aminoácidos , Substituição de Aminoácidos , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Mutação de Sentido Incorreto , Fosforilação/genética , Estrutura Terciária de Proteína , Transporte Proteico/genética , Receptor IGF Tipo 1/genética , Serina/genética , Serina/metabolismo
7.
Circ Cardiovasc Interv ; 4(4): 327-35, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21712526

RESUMO

BACKGROUND: Insulin-like growth factor-1 (IGF-1) is recognized as an important regulator of cardiac structure and cardiomyocyte homeostasis. The prosurvival and antiapoptotic effects of IGF-1 have been investigated in vitro and in rodent models of myocardial infarction (MI). However, the clinical application of IGF-1 has been hampered by dose-dependent side effects both acutely and during chronic administration. We hypothesized that single, low-dose IGF-1 (LD-IGF-1) administered locally and early in the reperfusion phase after acute MI in a large animal model would avoid significant side effects but would have prosurvival effects that would manifest in long-term structural and functional improvement after MI treatment. METHODS AND RESULTS: Forty-four female Landrace pigs underwent intracoronary administration of LD-IGF-1 or saline 2 hours into the reperfusion phase of acute left anterior descending artery occlusion MI. In the area of infarction, IGF-1 receptor and signaling responses were activated at 30 minutes and cardiomyocyte cell death attenuated at 24 hours after LD-IGF-1 but not saline treatment. Hemodynamic and structural studies using pressure-volume loop, CT, and triphenyltetrazolium chloride analysis 2 months post-MI confirmed a marked reduction in infarct size, attenuation of wall thinning, and augmentation of wall motion in the LD-IGF-1-treated but not in the saline-treated animals. These regional structural benefits were associated with global reductions in left ventricular volumes and significant improvement in left ventricular systolic and diastolic function. CONCLUSIONS: One-time LD-IGF-1 effects potent acute myocardial salvage in a preclinical model of left anterior descending artery occlusive MI, extending to long-term benefits in MI size, wall structure, and function and underscoring its potential as an adjunctive therapeutic agent.


Assuntos
Fator de Crescimento Insulin-Like I/administração & dosagem , Infarto do Miocárdio/tratamento farmacológico , Miócitos Cardíacos/efeitos dos fármacos , Fatores de Tempo , Animais , Apoptose/efeitos dos fármacos , Protocolos Clínicos , Feminino , Hemodinâmica , Humanos , Fator de Crescimento Insulin-Like I/efeitos adversos , Modelos Animais , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Receptor IGF Tipo 1/metabolismo , Volume Sistólico , Suínos , Sais de Tetrazólio/metabolismo
8.
J Biomech ; 44(8): 1484-90, 2011 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-21481877

RESUMO

The mechanical properties of cells are reported to be regulated by a range of factors including interactions with the extracellular environment and other cells, differentiation status, the onset of pathological states, as well as the intracellular factors, for example, the cytoskeleton. The cell cycle is considered to be a well-ordered sequence of biochemical events. A number of processes reported to occur during its progression are inherently mechanical and, as such, require mechanical regulation. In spite of this, few attempts have been made to investigate the putative regulatory role of the cell cycle in mechanobiology. In the present study, Atomic Force Microscopy (AFM) was employed to investigate the elastic modulus of synchronised osteoblasts. The data obtained confirm that osteoblast elasticity is regulated by cell cycle phase; specifically, cells in S phase were found to have a modulus approximately 1.7 times that of G1 phase cells. Confocal microscopy studies revealed that aspects of osteoblast morphology, namely F-actin expression, were also modulated by the cell cycle, and tended to increase with phase progression from G0 onwards. The data obtained in this study are likely to have implications for the fields of tissue- and bio-engineering, where prior knowledge of cell mechanobiology is essential for the effective replacement and repair of tissue. Furthermore, studies focused on biomechanics and the biophysical properties of cells are important in the understanding of the onset and progression of disease states, for example cancer at the cellular level. Our study demonstrates the importance of the combined use of traditional and relatively novel microscopy techniques in understanding mechanical regulation by crucial cellular processes, such as the cell cycle.


Assuntos
Osso e Ossos/patologia , Osteoblastos/citologia , Células 3T3 , Actinas/biossíntese , Animais , Fenômenos Biomecânicos , Engenharia Biomédica , Biofísica/métodos , Ciclo Celular , Citoesqueleto/metabolismo , Elasticidade , Citometria de Fluxo/métodos , Camundongos , Microscopia de Força Atômica/métodos , Microscopia Confocal , Modelos Biológicos
9.
J Biomech ; 44(1): 143-9, 2011 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-20883996

RESUMO

Muscle contractions begin in early embryonic life, generating forces that regulate the correct formation of the skeleton. In this paper we test the hypothesis that the biophysical stimulation generated by muscle forces may be a causative factor for the changes in shape of the knee joint as it grows. We do this by predicting the spatial and temporal patterns of biophysical stimuli, where cell proliferation and rudiment shape changes occur within the emerging tissues of the joint over time. We used optical projection tomography (OPT) to create anatomically accurate finite element models of the embryonic knee at three time points (stages) of development. OPT was also used to locate muscle attachment sites and AFM was used to determine material properties. An association was found between the emergence of joint shape, cell proliferation and the pattern of biophysical stimuli generated by embryonic muscle contractions. Elevated rates of growth and cell proliferation in the medial condyle were found to co-localise with elevated patterns of biophysical stimuli including maximum principal stresses and fluid flow, throughout the time period studied, indicating that cartilage growth and chondrocyte proliferation in the epiphysis is potentially related to local patterns of biophysical stimuli. The development of the patella and articular cartilages, which is known to be affected by in ovo immobilisation, could be contributed to by specific patterns of fluid flow, pore pressure and stress in the joint interzone. This suggests that both cartilage growth and tissue differentiation in the embryonic joint is regulated by specific patterns of biophysical stimuli and that these stimuli are needed for the correct development of the joint.


Assuntos
Articulações/embriologia , Articulações/fisiologia , Animais , Fenômenos Biomecânicos , Fenômenos Biofísicos , Cartilagem Articular/embriologia , Cartilagem Articular/fisiologia , Proliferação de Células , Embrião de Galinha , Condrócitos/citologia , Módulo de Elasticidade , Análise de Elementos Finitos , Imageamento Tridimensional , Microscopia de Força Atômica , Modelos Anatômicos , Modelos Biológicos , Morfogênese , Tomografia Óptica
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