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1.
Trials ; 25(1): 554, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39175005

RESUMEN

INTRODUCTION: ASCEND PLUS is a randomised controlled trial assessing the effects of oral semaglutide on the primary prevention of cardiovascular events in around 20,000 individuals with type 2 diabetes in the UK. The trial's innovative design includes a decentralised direct-to-participant invitation, recruitment, and follow-up model, relying on self-completion of online forms or telephone or video calls with research nurses, with no physical sites. Extensive patient and public involvement and engagement (PPIE) was essential to the design and conduct of ASCEND PLUS. AIM: To report the process and conduct of PPIE activity in ASCEND PLUS, evaluate effects on trial design, reflect critically on successes and aspects that could have been improved, and identify themes and learning relevant to implementation of PPIE in future trials. METHODS: PPIE activity was coordinated centrally and included six PPIE focus groups and creation of an ASCEND PLUS public advisory group (PAG) during the design phase. Recruitment to these groups was carefully considered to ensure diversity and inclusion, largely consisting of adults living with type 2 diabetes from across the UK. Two members of the PAG also joined the trial Steering Committee. Steering Committee meetings, focus groups, and PAG meetings were conducted online, with two hybrid workshops to discuss PPIE activity and aspects of the trial. RESULTS: PPIE activity was critical to shaping the design and conduct of ASCEND PLUS. Key examples included supporting choice for participants to either complete the screening/consent process independently online, or during a telephone or video call interview with a research nurse. A concise 'initial information leaflet' was developed to be sent with the initial invitations, with the 'full' information leaflet sent later to those interested in joining the trial. The PAG reviewed the content and format of participant- and public-facing materials, including written documents, online screening forms, animated videos, and the trial website, to aid clarity and accessibility, and provided input into the choice of instruments to assess quality of life. CONCLUSIONS: PPIE is integral in ASCEND PLUS and will continue throughout the trial. This involvement has been critical to optimising the trial design, successfully obtaining regulatory and ethical approval, and conducting the trial.


Asunto(s)
Diabetes Mellitus Tipo 2 , Participación del Paciente , Proyectos de Investigación , Humanos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Enfermedades Cardiovasculares/prevención & control , Hipoglucemiantes/uso terapéutico , Resultado del Tratamiento , Selección de Paciente , Participación de la Comunidad , Administración Oral , Reino Unido , Participación de los Interesados , Péptidos Similares al Glucagón
2.
J Virol ; 91(21)2017 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-28814524

RESUMEN

The envelope glycoprotein of diverse endogenous and exogenous retroviruses is considered inherently immunosuppressive. Extensive work mapped the immunosuppressive activity to a highly conserved domain, termed the immunosuppressive domain (ISD), in the transmembrane (TM) subunit of the envelope glycoprotein and identified two naturally polymorphic key residues that afford immunosuppressive activity to distinct envelope glycoproteins. Concurrent mutation of these two key residues (E14R and A20F) in the envelope glycoprotein of the Friend murine leukemia virus (F-MLV) ISD has been reported to abolish its immunosuppressive activity, without affecting its fusogenicity, and to weaken the ability of the virus to replicate specifically in immunocompetent hosts. Here, we show that mutation of these key residues did, in fact, result in a substantial loss of F-MLV infectivity, independently of host immunity, challenging whether associations exist between the two. Notably, a loss of infectivity incurred by the F-MLV mutant with the E14R and A20F double ISD mutation was conditional on expression of the ecotropic envelope receptor murine cationic amino acid transporter-1 (mCAT1) in the virus-producing cell. Indeed, the F-MLV mutant retained infectivity when it was produced by human cells, which naturally lack mCAT1 expression, but not by murine cells. Furthermore, mCAT1 overexpression in human cells impaired the infectivity of both the F-MLV double mutant and the wild-type F-MLV strain, suggesting a finely tuned relationship between the levels of mCAT1 in the producer cell and the infectivity of the virions produced. An adverse effect on this relationship, rather than disruption of the putative ISD, is therefore more likely to explain the loss of F-MLV infectivity incurred by mutations in key ISD residues E14 and A20.IMPORTANCE Retroviruses can interact with their hosts in ways that, although not entirely understood, can greatly influence their pathogenic potential. One such example is a putative immunosuppressive activity, which has been mapped to a conserved domain of the retroviral envelope glycoprotein of several exogenous as well as endogenous retroviruses. In this study, mutations naturally found in some envelope glycoproteins lacking immunosuppressive activity were shown to affect retrovirus infectivity only if the host cell that produced the retrovirus also expressed the cellular entry receptor. These findings shed light on a novel role for this conserved domain in providing the necessary stability to the envelope glycoprotein in order to withstand the interaction with the cellular receptor during virus formation. This function of the domain is critical for further elucidation of the mechanism of immunosuppression mediated by the retroviral envelope glycoprotein.


Asunto(s)
Virus de la Leucemia Murina de Friend/patogenicidad , Mutación , Infecciones por Retroviridae/virología , Proteínas del Envoltorio Viral/genética , Secuencia de Aminoácidos , Animales , Femenino , Células HEK293 , Humanos , Terapia de Inmunosupresión , Masculino , Ratones , Ratones Endogámicos C57BL , Dominios Proteicos , Infecciones por Retroviridae/genética , Infecciones por Retroviridae/inmunología , Homología de Secuencia
4.
Sci Rep ; 7: 42874, 2017 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-28230058

RESUMEN

Glucose and glucose metabolites are able to adversely modify proteins through a non-enzymatic reaction called glycation, which is associated with the pathology of Alzheimer's Disease (AD) and is a characteristic of the hyperglycaemia induced by diabetes. However, the precise protein glycation profile that characterises AD is poorly defined and the molecular link between hyperglycaemia and AD is unknown. In this study, we define an early glycation profile of human brain using fluorescent phenylboronate gel electrophoresis and identify early glycation and oxidation of macrophage migration inhibitory factor (MIF) in AD brain. This modification inhibits MIF enzyme activity and ability to stimulate glial cells. MIF is involved in immune response and insulin regulation, hyperglycaemia, oxidative stress and glycation are all implicated in AD. Our study indicates that glucose modified and oxidised MIF could be a molecular link between hyperglycaemia and the dysregulation of the innate immune system in AD.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Encéfalo/metabolismo , Glucosa/metabolismo , Oxidorreductasas Intramoleculares/metabolismo , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Regulación de la Expresión Génica , Humanos , Hiperglucemia/metabolismo , Estrés Oxidativo
5.
Wellcome Open Res ; 1: 22, 2016 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-28111636

RESUMEN

To achieve persistent infection of the host, viruses often subvert or suppress host immunity through mechanisms that are not entirely understood. The envelope glycoprotein of several retroviruses is thought to possess potent immunosuppressive activity, mapped to a 17-amino acid residue conserved domain. Synthetic peptides corresponding to this immunosuppressive domain can inhibit lymphocyte activation, whereas mutation of key domain residues can increase the lymphocyte response to linked antigenic epitopes. Using three T cell receptors (TCRs) of defined specificity, we examine the effect of the immunosuppressive domain on the T cell response to their respective antigenic peptides. We find that fusion of a T cell epitope to the immunosuppressive domain can greatly modulate its potency. However, the effects heavily depend on the particular combination of TCR and peptide-major histocompatibility complex class II (pMHC II), and are mimicked by sequence-scrambled peptides of similar length, suggesting they operate at the level of TCR-pMHC interaction. These results offer an alternative explanation for the immunogenicity of T cell epitopes comprising the putative immunosuppressive domain, which is more consistent with an effect on peptide antigenicity than true immunosuppressive activity.

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