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1.
Lancet Rheumatol ; 6(2): e92-e104, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38267107

RESUMO

BACKGROUND: Methotrexate is the first-line treatment for immune-mediated inflammatory diseases and reduces vaccine-induced immunity. We evaluated if a 2-week interruption of methotrexate treatment immediately after COVID-19 booster vaccination improved antibody response against the S1 receptor binding domain (S1-RBD) of the SARS-CoV-2 spike protein and live SARS-CoV-2 neutralisation compared with uninterrupted treatment in patients with immune-mediated inflammatory diseases. METHOD: We did a multicentre, open-label, parallel-group, randomised, superiority trial in secondary-care rheumatology and dermatology clinics in 26 hospitals in the UK. Adults (aged ≥18 years) with immune-mediated inflammatory diseases taking methotrexate (≤25 mg per week) for at least 3 months, who had received two primary vaccine doses from the UK COVID-19 vaccination programme were eligible. Participants were randomly assigned (1:1) using a centralised validated computer program, to temporarily suspend methotrexate treatment for 2 weeks immediately after COVID-19 booster vaccination or continue treatment as usual. The primary outcome was S1-RBD antibody titres 4 weeks after COVID-19 booster vaccination and was assessed masked to group assignment. All randomly assigned patients were included in primary and safety analyses. This trial is registered with ISRCTN, ISRCTN11442263; following a pre-planned interim analysis, recruitment was stopped early. FINDING: Between Sept 30, 2021, and March 7, 2022, we screened 685 individuals, of whom 383 were randomly assigned: to either suspend methotrexate (n=191; mean age 58·8 years [SD 12·5], 118 [62%] women and 73 [38%] men) or to continue methotrexate (n=192; mean age 59·3 years [11·9], 117 [61%] women and 75 [39%] men). At 4 weeks, the geometric mean S1-RBD antibody titre was 25 413 U/mL (95% CI 22 227-29 056) in the suspend methotrexate group and 12 326 U/mL (10 538-14 418) in the continue methotrexate group with a geometric mean ratio (GMR) of 2·08 (95% CI 1·59-2·70; p<0·0001). No intervention-related serious adverse events occurred. INTERPRETATION: 2-week interruption of methotrexate treatment in people with immune-mediated inflammatory diseases enhanced antibody responses after COVID-19 booster vaccination that were sustained at 12 weeks and 26 weeks. There was a temporary increase in inflammatory disease flares, mostly self-managed. The choice to suspend methotrexate should be individualised based on disease status and vulnerability to severe outcomes from COVID-19. FUNDING: National Institute for Health and Care Research.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Glicoproteína da Espícula de Coronavírus , Adulto , Masculino , Humanos , Feminino , Adolescente , Pessoa de Meia-Idade , Vacinas contra COVID-19/efeitos adversos , Metotrexato/uso terapêutico , SARS-CoV-2
2.
Lancet Rheumatol ; 4(10): e725-e737, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36341025

RESUMO

Background: Symptomatic hand osteoarthritis is more common in women than in men, and its incidence increases around the age of menopause, implicating oestrogen deficiency. No randomised controlled trials of hormone replacement therapy (HRT) have been done in people with hand osteoarthritis. We aimed to determine the feasibility and acceptability of a form of HRT (conjugated oestrogens plus bazedoxifene) in post-menopausal women with painful hand osteoarthritis. Methods: The HOPE-e feasibility study was a randomised, double-blind, placebo-controlled trial, for which we recruited women aged 40-65 years, for whom 1-10 years had passed after their final menstrual period, with definite hand osteoarthritis and at least two painful hand joints. Participants were recruited across three primary or secondary care sites and from the community and were randomly assigned (1:1) to receive conjugated oestrogens plus bazedoxifene or placebo, orally once every day for 24 weeks, before weaning for 4 weeks until the end of the study. The primary feasibility outcomes were rates of identification, recruitment, randomisation, retention, and compliance of eligible participants, and the likelihood of unmasking. The secondary objective was to generate proof-of-concept quantitative and qualitative data on the acceptability of proposed clinical outcomes for a full trial and adverse events. We used an intention-to-treat analysis, and criteria for progression to a full trial were pre-defined as recruitment of at least 30 participants across all sites in 18 months; a dropout rate of less than or equal to 30% of randomised individuals; and acceptability to the majority of participants, including acceptable rates of adverse events. Due to the COVID-19 pandemic, the recruitment window was reduced to 12-15 months. A proportionately reduced minimum sample size of 22 was judged to be sufficient to test feasibility. This trial was registered at ISRCTN, ISRCTN12196200. Findings: From May 9, 2019 to Dec 31, 2020, 434 enquiries or referrals were received. We did 96 telephone pre-screens; of the 35 eligible participants, seven were excluded as ineligible at the telephone or face-to-face screening and 28 (80% [95% CI 63-92]) were randomly assigned. Of the 406 who were not randomly assigned, 250 (62%) were ineligible (with contraindicated medications accounting for 50 [20%] of these), 101 (25%) did not respond to further enquiries, and 55 (14%) chose not to proceed (with the most common reason being not wanting to take a hormone-based drug). All 28 randomised participants completed all follow-up assessments with high compliance and outcome measure completeness. All three adverse event-related treatment withdrawals were in the placebo group. No serious adverse events were reported. Participants and investigators were successfully masked (participant Bang's blinding index placebo group 0·50 [95% CI 0·25-0·75]). The trial met the prespecified criteria for progression to a full trial. Interpretation: This first-ever feasibility study of a randomised controlled trial of HRT for post-menopausal women with painful hand osteoarthritis met its progression criteria, although it was not powered to detect a clinical effect. This outcome indicates that a full trial of an HRT in this population is feasible and acceptable and identifies potential refinements with regard to the design of such a trial. Funding: Research for Patient Benefit programme, National Institute for Health Research.

3.
Pilot Feasibility Stud ; 7(1): 133, 2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34167594

RESUMO

BACKGROUND: Hand osteoarthritis (OA) is a common condition, causing pain, stiffness and reduced quality of life. Incidence is higher amongst women, particularly around the age of the menopause. Whilst the relationship between sex hormones and OA has been studied in vitro, in epidemiological studies and in clinical trials of hormone replacement therapy (HRT), this study is the first to investigate the effect of estrogen-containing therapy on hand pain in post-menopausal women with symptomatic hand OA in a randomised study design. METHODS: This is a feasibility study of a double-blinded placebo-controlled intervention with 1:1 randomisation to either a combination of conjugated estrogens 0.45 mg and bazedoxifene acetate 20 mg (Duavive) or placebo. The target population is post-menopausal women with symptomatic hand OA, aiming to recruit 60-90 study participants. The primary objective is to assess the feasibility of a future fully powered randomised controlled trial (RCT). Participants will take the study medication for 24 weeks and be followed up for 28 weeks after randomisation. The primary outcomes used to determine feasibility are eligible participant identification rates and routes; recruitment, randomisation and retention rates of eligible participants; study medication compliance; and the likelihood of unintentional unblinding. Secondary outcomes include measures of hand pain, function, appearance and menopausal symptoms. An end of study questionnaire and focus groups will help to refine the final protocol for a full study. DISCUSSION: Identifying new treatments for symptomatic hand OA is a recognised research priority. The study will help us to understand whether there are sufficient interested and eligible individuals in this target population who would consider HRT for their hand symptoms. It will provide proof-of-concept RCT data on the effects of HRT on hand pain and other clinically relevant outcomes in this population. The study will gain valuable information on the feasibility of a full RCT and how best to run this. The findings will be published in a peer-reviewed journal and presented at a relevant conference. TRIAL REGISTRATION: ISRCTN12196200 registered on 15 January 2019.

4.
PLoS One ; 11(8): e0161898, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27564415

RESUMO

The purpose of this study was to examine the retinas of mice carrying hemizygous and null double deletions of Cfb-/- and Cfh-/-, and to compare these with the single knockouts of Cfb, Cfh and Cfd. Retinas were isolated from wild type (WT), Cfb-/-/Cfh-/-, Cfb-/-/Cfh+/-, Cfh-/-/Cfb+/-, Cfb-/-, Cfh-/- Cfd-/-, and Cfd+/- mice. Complement proteins were evaluated by western blotting, ELISA and immunocytochemistry, and retinal morphology was assessed using toluidine blue stained semi-thin sections. WT mice showed staining for C3 and its breakdown products in the retinal vasculature and the basal surface of the retinal pigment epithelium (RPE). Cfb-/- mice exhibited a similar C3 staining pattern to WT in the retinal vessels but a decrease in C3 and its breakdown products at the basal surface of the RPE. Deletion of both Cfb and Cfh restored C3 to levels similar to those observed in WT mice, however this reversal of phenotype was not observed in Cfh-/-/Cfb+/- or Cfb-/-/Cfh+/- mice. Loss of CFD caused an increase in C3 and a decrease in C3 breakdown products along the basal surface of the RPE. Overall the retinal morphology and retinal vasculature did not appear different across the various genotypes. We observed that C3 accumulates at the basal RPE in Cfb-/-, Cfb-/-/Cfh-/-, Cfb-/-/Cfh+/-, Cfd-/- and WT mice, but is absent in Cfh-/- and Cfh-/-/Cfb+/- mice, consistent with its consumption in the serum of mice lacking CFH when CFB is present. C3 breakdown products along the surface of the RPE were either decreased or absent when CFB, CFH or CFD was deleted or partially deleted.


Assuntos
Convertases de Complemento C3-C5/metabolismo , Via Alternativa do Complemento/fisiologia , Retina/metabolismo , Animais , Western Blotting , Complemento C5/genética , Complemento C5/metabolismo , Fator B do Complemento/genética , Fator B do Complemento/metabolismo , Fator D do Complemento/genética , Fator D do Complemento/metabolismo , Fator H do Complemento/genética , Fator H do Complemento/metabolismo , Via Alternativa do Complemento/genética , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes
5.
Apoptosis ; 20(4): 433-43, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25735751

RESUMO

The loss of photoreceptors is the defining characteristic of many retinal degenerative diseases, but the mechanisms that regulate photoreceptor cell death are not fully understood. Here we have used the 661W cone photoreceptor cell line to ask whether exposure to the terminal complement complex C5b-9 induces cell death and/or modulates the sensitivity of these cells to other cellular stressors. 661W cone photoreceptors were exposed to complete normal human serum following antibody blockade of CD59. Apoptosis induction was assessed morphologically, by flow cytometry, and on western blotting by probing for cleaved PARP and activated caspase-3. Necroptosis was assessed by flow cytometry and Sirtuin 2 inhibition using 2-cyano-3-[5-(2,5-dichlorophenyl)-2-furyl]-N-5-quinolinylacrylamide (AGK2). The sensitivity of 661W cells to ionomycin, staurosporine, peroxide and chelerythrine was also investigated, with or without prior formation of C5b-9. 661W cells underwent apoptotic cell death following exposure to C5b-9, as judged by poly(ADP-ribose) polymerase 1 cleavage and activation of caspase-3. We also observed apoptotic cell death in response to staurosporine, but 661W cells were resistant to both ionomycin and peroxide. Interestingly, C5b-9 significantly increased 661W sensitivity to staurosporine-induced apoptosis and necroptosis. These studies show that low levels of C5b-9 on 661W cells can induce apoptosis, and that C5b-9 specifically sensitizes 661W cells to certain apoptotic and necroptotic pathways. Our observations provide new insight into the potential role of the complement system in photoreceptor loss, with implications for the molecular aetiology of retinal disease.


Assuntos
Apoptose , Complemento C5b/metabolismo , Complemento C6/metabolismo , Complemento C7/metabolismo , Complemento C8/metabolismo , Complemento C9/metabolismo , Células Fotorreceptoras/citologia , Células Fotorreceptoras/metabolismo , Caspase 3/metabolismo , Linhagem Celular , Complexo de Ataque à Membrana do Sistema Complemento/metabolismo , Humanos , Necrose
6.
PLoS One ; 8(7): e68616, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23844226

RESUMO

We previously reported that aged mice lacking complement factor H (CFH) exhibit visual defects and structural changes in the retina. However, it is not known whether this phenotype is age-related or is the consequence of disturbed development. To address this question we investigated the effect of Cfh gene deletion on the retinal phenotype of young and mid-age mice. Cfh(-/-) mouse eyes exhibited thickening of the retina and reduced nuclear density, but relatively normal scotopic and photopic electroretinograms. At 12 months there was evidence of subtle astroglial activation in the Cfh(-/-) eyes, and significant elevation of the complement regulator, decay-accelerating factor (DAF) in Müller cells. In the retinal pigment epithelium (RPE) of young control and Cfh(-/-) animals mitochondria and melanosomes were oriented basally and apically respectively, whereas the apical positioning of melanosomes was significantly perturbed in the mid-age Cfh(-/-) RPE. We conclude that deletion of Cfh in the mouse leads to defects in the retina that precede any marked loss of visual function, but which become progressively more marked as the animals age. These observations are consistent with a lifelong role for CFH in retinal homeostasis.


Assuntos
Envelhecimento , Fator H do Complemento/fisiologia , Retina/fisiopatologia , Acuidade Visual/fisiologia , Animais , Antígenos CD55/metabolismo , Fator H do Complemento/deficiência , Fator H do Complemento/genética , Eletrorretinografia , Potenciais Evocados Visuais/genética , Potenciais Evocados Visuais/fisiologia , Proteína Glial Fibrilar Ácida/metabolismo , Imuno-Histoquímica , Melanossomas/metabolismo , Melanossomas/ultraestrutura , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Estimulação Luminosa , Retina/metabolismo , Retina/patologia , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/ultraestrutura , Acuidade Visual/genética , Vias Visuais/fisiopatologia
7.
J Biol Chem ; 282(17): 12397-409, 2007 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-17339324

RESUMO

The two lectin receptors, CLEC-2 and Dectin-1, have been shown to signal through a Syk-dependent pathway, despite the presence of only a single YXXL in their cytosolic tails. In this study, we show that stimulation of CLEC-2 in platelets and in two mutant cell lines is dependent on the YXXL motif and on proteins that participate in signaling by immunoreceptor tyrosine-based activation motif receptors, including Src, Syk, and Tec family kinases, and on phospholipase Cgamma. Strikingly, mutation of either Src homology (SH) 2 domain of Syk blocks signaling by CLEC-2 despite the fact that it has only a single YXXL motif. Furthermore, signaling by CLEC-2 is only partially dependent on the BLNK/SLP-76 family of adapter proteins in contrast to that of immunoreceptor tyrosine-based activation motif receptors. The C-type lectin receptor, Dectin-1, which contains a YXXL motif preceded by the same four amino acids as for CLEC-2 (DEDG), signals like CLEC-2 and also requires the two SH2 domains of Syk and is only partially dependent on the BLNK/SLP-76 family of adapters. In marked contrast, the C-type lectin receptor, DC-SIGN, which has a distinct series of amino acids preceding a single YXXL, signals independent of this motif. A mutational analysis of the DEDG sequence of CLEC-2 revealed that the glycine residue directly upstream of the YXXL tyrosine is important for CLEC-2 signaling. These results demonstrate that CLEC-2 and Dectin-1 signal through a single YXXL motif that requires the tandem SH2 domains of Syk but is only partially dependent on the SLP-76/BLNK family of adapters.


Assuntos
Plaquetas/metabolismo , Moléculas de Adesão Celular/metabolismo , Lectinas Tipo C/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptores de Superfície Celular/metabolismo , Transdução de Sinais/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Motivos de Aminoácidos/genética , Animais , Moléculas de Adesão Celular/genética , Linhagem Celular , Galinhas , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Lectinas Tipo C/genética , Glicoproteínas de Membrana/genética , Proteínas de Membrana/genética , Mutação , Proteínas do Tecido Nervoso/genética , Proteínas Tirosina Quinases/metabolismo , Receptores de Superfície Celular/genética , Quinase Syk , Domínios de Homologia de src/genética , Quinases da Família src/metabolismo
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