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1.
Artículo en Inglés | MEDLINE | ID: mdl-38821172

RESUMEN

INTRODUCTION: Posterior shoulder instability (PSI) is an increasingly recognized cause of shoulder dysfunction particularly in young active patients and certain athlete populations. When evaluating the efficacy of treatment for PSI, specific outcome measures for this population are essential. The aim of the current research was to describe the development and evaluation of a patient reported outcome measure (PROM) specific for PSI. METHODS: A retrospective cohort study design of patients with PSI was used to develop and evaluate the "Posterior Shoulder Instability Questionnaire (PSI-Q)". Items for PSI-Q were generated through an expert focus group and existing questionnaires. Preliminary data analysis identified redundancy of items and resulted in the PSI-Q being refined. The final PSI-Q was evaluated on 128 patients with PSI with a structural lesion requiring surgical intervention. Participants were excluded in the absence of a posterior glenohumeral joint lesion. Internal consistency (Cronbach α and corrected item-total correlation), content validity, criterion validity, responsiveness, and test-retest reliability (intraclass correlation coefficient; ICC) were examined. Content validity, criterion validity and responsiveness were compared with the Melbourne Instability Shoulder Score (MISS) and the Western Ontario Shoulder Index (WOSI). The minimum detectable change score (MDC) was calculated. RESULTS: The Cronbach α for the total scale pre and post-intervention was high (α = 0.97). All five domains (Pain, Instability/Weakness/Stiffness, Function, Occupation and Sport, and Quality of Life and Satisfaction) demonstrated acceptable internal consistency for each subsection and the overall score of the scale (α > 0.70). The corrected-item total correlation for each domain were within an acceptable range. The responsiveness of the PSI-Q questionnaire was excellent (effect size, 2.06; standard response mean, 1.34) and was higher than the MISS and WOSI. There were no relevant floor effects and one ceiling effect. Reliability was excellent (ICC (1,1) = 0.93) and the calculated MDC was 10.9 points. DISCUSSION: This study designed and validated a questionnaire specific for measuring symptoms and function in people with structural PSI requiring surgery. The PSI-Q demonstrates good measurement properties and provides an MDC that is useful for researchers and clinicians. In structural PSI, the PSI-Q has a higher responsiveness and more accurately reflects a patient's overall perceived shoulder status compared to current patient reported outcomes for shoulder instability. The psychometric properties of the PSI-Q are still to be determined in a non-surgical population.

2.
Int J Mol Sci ; 21(19)2020 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-33027962

RESUMEN

T cells follow a triphasic distinct pathway of activation, proliferation and differentiation before becoming functionally and phenotypically "exhausted" in settings of chronic infection, autoimmunity and in cancer. Exhausted T cells progressively lose canonical effector functions, exhibit altered transcriptional networks and epigenetic signatures and gain constitutive expression of a broad coinhibitory receptor suite. This review outlines recent advances in our understanding of exhausted T cell biology and examines cellular and molecular mechanisms by which a state of dysfunction or exhaustion is established, and mechanisms by which exhausted T cells may still contribute to pathogen or tumour control. Further, this review describes our understanding of exhausted T cell heterogeneity and outlines the mechanisms by which checkpoint blockade differentially engages exhausted T cell subsets to overcome exhaustion and recover T cell function.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Activación de Linfocitos/inmunología , Neoplasias/tratamiento farmacológico , Neoplasias/inmunología , Linfocitos T CD8-positivos/efectos de los fármacos , Diferenciación Celular/genética , Humanos , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Activación de Linfocitos/efectos de los fármacos , Neoplasias/genética , Subgrupos de Linfocitos T/efectos de los fármacos , Subgrupos de Linfocitos T/inmunología
3.
J Hepatol ; 71(5): 900-907, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31306680

RESUMEN

BACKGROUND & AIMS: To evaluate the hypothesis that increasing T cell frequency and activity may provide durable control of hepatitis B virus (HBV), we administered nivolumab, a programmed death receptor 1 (PD-1) inhibitor, with or without GS-4774, an HBV therapeutic vaccine, in virally suppressed patients with HBV e antigen (HBeAg)-negative chronic HBV. METHODS: In a phase Ib study, patients received either a single dose of nivolumab at 0.1 mg/kg (n = 2) or 0.3 mg/kg (n = 12), or 40 yeast units of GS-4774 at baseline and week 4 and 0.3 mg/kg of nivolumab at week 4 (n = 10). The primary efficacy endpoint was mean change in HBV surface antigen (HBsAg) 12 weeks after nivolumab. Safety and immunologic changes were assessed through week 24. RESULTS: There were no grade 3 or 4 adverse events or serious adverse events. All assessed patients retained T cell PD-1 receptor occupancy 6-12 weeks post-infusion, with a mean total across 0.1 and 0.3 mg/kg cohorts of 76% (95% CI 75-77), and no significant differences were observed between cohorts (p = 0.839). Patients receiving 0.3 mg/kg nivolumab without and with GS-4774 had mean declines of -0.30 (95% CI -0.46 to -0.14) and -0.16 (95% CI -0.33 to 0.01) log10 IU/ml, respectively. Patients showed significant HBsAg declines from baseline (p = 0.035) with 3 patients experiencing declines of >0.5 log10 by the end of study. One patient, whose HBsAg went from baseline 1,173 IU/ml to undetectable at week 20, experienced an alanine aminotransferase flare (grade 3) at week 4 that resolved by week 8 and was accompanied by a significant increase in peripheral HBsAg-specific T cells at week 24. CONCLUSIONS: In virally suppressed HBeAg-negative patients, checkpoint blockade was well-tolerated and led to HBsAg decline in most patients and sustained HBsAg loss in 1 patient. LAY SUMMARY: Chronic hepatitis B virus infection (CHB) is characterized by a dysfunctional immune response. In patients with CHB, inhibitory receptors, such as programmed death receptor 1 (PD-1) are overexpressed on T cells, leading to an ineffective immune response in the liver. Herein, we show that the PD-1 inhibitor, nivolumab, is safe and effective for the treatment of virally suppressed patients with CHB. Australian New Zealand Clinical Trials Registry (http://www.anzctr.org.au/) number: ACTRN12615001133527.


Asunto(s)
Vacunas contra Hepatitis B/administración & dosificación , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/tratamiento farmacológico , Inhibidores de Puntos de Control Inmunológico/administración & dosificación , Nivolumab/administración & dosificación , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Vacunación , Adulto , Anciano , ADN Viral/sangre , Femenino , Estudios de Seguimiento , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/inmunología , Antígenos e de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/inmunología , Hepatitis B Crónica/epidemiología , Hepatitis B Crónica/virología , Humanos , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Inhibidores de Puntos de Control Inmunológico/farmacología , Masculino , Persona de Mediana Edad , Nueva Zelanda/epidemiología , Nivolumab/efectos adversos , Nivolumab/farmacología , Proyectos Piloto , Receptor de Muerte Celular Programada 1/metabolismo , Linfocitos T/inmunología , Linfocitos T/metabolismo , Resultado del Tratamiento
4.
Immunol Cell Biol ; 94(10): 955-963, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27301418

RESUMEN

The homeostatic chemokine CCL21 has a pivotal role in lymphocyte homing and compartment localisation within the lymph node, and also affects adhesion between immune cells. The effects of CCL21 are modulated by its mode of presentation, with different cellular responses seen for surface-bound and soluble forms. Here we show that plasmin cleaves surface-bound CCL21 to release the C-terminal peptide responsible for CCL21 binding to glycosaminoglycans on the extracellular matrix and cell surfaces, thereby generating the soluble form. Loss of this anchoring peptide enabled the chemotactic activity of CCL21 and reduced cell tethering. Tissue plasminogen activator did not cleave CCL21 directly but enhanced CCL21 processing through generation of plasmin from plasminogen. The tissue plasminogen activator inhibitor neuroserpin prevented processing of CCL21 and blocked the effects of soluble CCL21 on cell migration. Similarly, the plasmin-specific inhibitor α2-antiplasmin inhibited CCL21-mediated migration of human T cells and dendritic cells and tethering of T cells to APCs. We conclude that the plasmin system proteins plasmin, tissue plasminogen activator and neuroserpin regulate CCL21 function in the immune system by controlling the balance of matrix- and cell-bound CCL21.


Asunto(s)
Movimiento Celular/efectos de los fármacos , Quimiocina CCL21/metabolismo , Células Dendríticas/citología , Células Dendríticas/metabolismo , Plasminógeno/farmacología , Linfocitos T/citología , Linfocitos T/metabolismo , Secuencia de Aminoácidos , Adhesión Celular/efectos de los fármacos , Comunicación Celular/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Quimiocina CCL21/química , Células Dendríticas/efectos de los fármacos , Humanos , Neuropéptidos/farmacología , Unión Proteica/efectos de los fármacos , Proteínas Recombinantes/metabolismo , Serpinas/farmacología , Linfocitos T/efectos de los fármacos , Activador de Tejido Plasminógeno/farmacología , alfa 2-Antiplasmina/farmacología , Neuroserpina
5.
Org Biomol Chem ; 13(23): 6567-72, 2015 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-25978133

RESUMEN

Herein, we report the facile preparation of cell-targeted platinum nanoparticles (PtNPs), through the design of peptides that, as a single molecule added in small concentration during the synthesis, control the size of PtNP clusters during their growth, stabilise the PtNPs in aqueous suspension and enable the functionalisation of the PtNPs with a versatile range of cell-targeting ligands. Water-soluble PtNPs targeted respectively at blood group antigens and at integrin receptors are demonstrated.


Asunto(s)
Bioquímica/métodos , Nanopartículas del Metal/química , Platino (Metal)/química , Células 3T3/efectos de los fármacos , Animales , Antígenos de Grupos Sanguíneos/metabolismo , Concanavalina A/química , Eritrocitos/efectos de los fármacos , Eritrocitos/metabolismo , Humanos , Integrina alfaVbeta3/metabolismo , Ligandos , Nanopartículas del Metal/ultraestructura , Ratones , Microscopía Electrónica de Transmisión , Péptidos/síntesis química , Péptidos/química , Platino (Metal)/farmacología , Ratas , Solubilidad
6.
J Transl Med ; 12: 292, 2014 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-25331734

RESUMEN

BACKGROUND: microRNAs (miRNAs) are emerging as key regulators of the immune system, but their role in CD8+ T cell differentiation is not well explored. Some evidence suggests that signals from cell surface receptors influence the expression of miRNAs in CD8+ T cells, and may have consequent effects on cell phenotype and function. We set out to investigate whether common gamma chain cytokines modulated human CD8+ T cell expression of miR-146a, which previous studies have associated with different stages of CD8+ differentiation. We also investigated how changes in miR-146a related to other miRNAs that alter with CD8+ differentiation status. METHODS: We treated human CD8+ T cells with the cytokines IL-2, IL-7 or IL-15 either at rest or after stimulation with anti-CD3 and anti-CD28. For some experiments we also purified human CD8+ T cell subsets ex vivo. Flow cytometry was used in parallel to assess cell surface memory marker expression. Total RNA from these cells was subjected to microarray analysis and real-time PCR for miRNA expression. Nucleofection studies were performed to assess potential mRNA targets of miR-146a. RESULTS: We find that miR-146a is up-regulated in naïve CD8+ T cells exposed to IL-2 or IL-15, even in the absence of an activating T cell receptor stimulus, but not when IL-7 is also present. miR-146a expression correlates with a memory phenotype in both ex vivo and in vitro cultured cells although in our hands overexpression of miR-146a was not sufficient alone to drive a full memory phenotype. In ex vivo analysis, miR-146a was one of a small number of miRNAs that was differentially expressed between naïve and memory CD8+ T cells. CONCLUSIONS: miR-146a is emerging as a critical regulator of immune system. Our data shows that miR-146a expression is strongly influenced by the cytokine milieu even in the absence of a T cell receptor stimulus. Our results have implications for studies designed to assess the function of miR-146a, help to define a fingerprint of miRNA expression in CD8+ T cell subsets and may be useful when designing optimal protocols for T cell expansion as efficacy of T cell immunotherapy is correlated with an 'early' memory phenotype.


Asunto(s)
Linfocitos T CD8-positivos/metabolismo , Citocinas/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , MicroARNs/genética , Subgrupos de Linfocitos T/metabolismo , Antígenos/metabolismo , Linfocitos T CD8-positivos/efectos de los fármacos , Proteína de Dominio de Muerte Asociada a Fas/metabolismo , Perfilación de la Expresión Génica , Humanos , Memoria Inmunológica , Interleucina-15/farmacología , Interleucina-2/farmacología , Interleucina-7/farmacología , MicroARNs/metabolismo , Fenotipo , Receptores de Antígenos de Linfocitos T/metabolismo , Receptores CCR7/metabolismo , Subgrupos de Linfocitos T/efectos de los fármacos , Factor 6 Asociado a Receptor de TNF/metabolismo , Regulación hacia Arriba/efectos de los fármacos
7.
Front Immunol ; 15: 1412076, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38903497

RESUMEN

Macrophages play essential roles in maintaining tissue homeostasis and immune defence. However, their extensive infiltration into tumours has been linked to adverse outcomes in multiple human cancers. Within the tumour microenvironment (TME), tumour-associated macrophages (TAMs) promote tumour growth and metastasis, making them prime targets for cancer immunotherapy. Recent single-cell analysis suggest that proliferating TAMs accumulate in human cancers, yet their origins and differentiation pathways remain uncertain. Here, we show that a subpopulation of CD163+ TAMs proliferates in situ within the TME of melanoma, lung cancer, and breast cancer. Consistent with their potential role in suppressing anti-tumour activities of T cells, CD163+ TAMs express a range of potent immunosuppressive molecules, including PD-L1, PD-L2, IL-10, and TGF-ß. Other phenotypic markers strongly suggested that these cells originate from CD14+ CCR2+ monocytes, a cell population believed to have minimal capacity for proliferation. However, we demonstrate in vitro that certain myelopoietic cytokines commonly available within the TME induce robust proliferation of human monocytes, especially the combination of interleukin 3 (IL-3) and Macrophage Colony-Stimulating Factor 1 (M-CSF). Monocytic cells cultured with these cytokines efficiently modulate T cell proliferation, and their molecular phenotype recapitulates that of CD163+ TAMs. IL-3-driven proliferation of monocytic cells can be completely blocked by IL-4, associated with the induction of CDKN1A, alongside the upregulation of transcription factors linked to dendritic cell function, such as BATF3 and IRF4. Taken together, our work suggests several novel therapeutic routes to reducing immunosuppressive TAMs in human tumours, from blocking chemokine-mediated recruitment of monocytes to blocking their proliferation.


Asunto(s)
Proliferación Celular , Monocitos , Microambiente Tumoral , Macrófagos Asociados a Tumores , Humanos , Monocitos/inmunología , Monocitos/metabolismo , Microambiente Tumoral/inmunología , Macrófagos Asociados a Tumores/inmunología , Macrófagos Asociados a Tumores/metabolismo , Neoplasias/inmunología , Neoplasias/patología , Antígenos CD/metabolismo , Femenino , Macrófagos/inmunología , Macrófagos/metabolismo , Receptores de Superficie Celular/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Citocinas/metabolismo , Linfocitos T/inmunología , Linfocitos T/metabolismo , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/patología
8.
Virol J ; 8: 551, 2011 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-22185400

RESUMEN

BACKGROUND: Nonstructural glycoprotein 4 (NSP4) encoded by rotavirus is the only viral protein currently believed to function as an enterotoxin. NSP4 is synthesized as an intracellular transmembrane glycoprotein and as such is essential for virus assembly. Infection of polarized Caco-2 cells with rotavirus also results in the secretion of glycosylated NSP4 apparently in a soluble form despite retention of its transmembrane domain. We have examined the structure, solubility and cell-binding properties of this secreted form of NSP4 to further understand the biochemical basis for its enterotoxic function. We show here that NSP4 is secreted as discrete detergent-sensitive oligomers in a complex with phospholipids and demonstrate that this secreted form of NSP4 can bind to glycosaminoglycans present on the surface of a range of different cell types. METHODS: NSP4 was purified from the medium of infected cells after ultracentrifugation and ultrafiltration by successive lectin-affinity and ion exchange chromatography. Oligomerisation of NSP4 was examined by density gradient centrifugation and chemical crosslinking and the lipid content was assessed by analytical thin layer chromatography and flame ionization detection. Binding of NSP4 to various cell lines was measured using a flow cytometric-based assay. RESULTS: Secreted NSP4 formed oligomers that contained phospholipid but dissociated to a dimeric species in the presence of non-ionic detergent. The purified glycoprotein binds to the surface of various non-infected cells of distinct lineage. Binding of NSP4 to HT-29, a cell line of intestinal origin, is saturable and independent of divalent cations. Complementary biochemical approaches reveal that NSP4 binds to sulfated glycosaminoglycans on the plasma membrane. CONCLUSION: Our study is the first to analyze an authentic (i.e. non-recombinant) form of NSP4 that is secreted from virus-infected cells. Despite retention of the transmembrane domain, secreted NSP4 remains soluble in an aqueous environment as an oligomeric lipoprotein that can bind to various cell types via an interaction with glycosaminoglycans. This broad cellular tropism exhibited by NSP4 may have implications for the pathophysiology of rotavirus disease.


Asunto(s)
Membrana Celular/metabolismo , Glicoproteínas/metabolismo , Glicosaminoglicanos/metabolismo , Lipoproteínas/metabolismo , Rotavirus/patogenicidad , Toxinas Biológicas/metabolismo , Proteínas no Estructurales Virales/metabolismo , Animales , Células CACO-2 , Membrana Celular/química , Colon/citología , Colon/virología , Medios de Cultivo Condicionados/química , Células Epiteliales/metabolismo , Células Epiteliales/virología , Glicoproteínas/aislamiento & purificación , Células HT29 , Humanos , Multimerización de Proteína , Rotavirus/metabolismo , Toxinas Biológicas/aislamiento & purificación , Proteínas no Estructurales Virales/aislamiento & purificación
9.
Cancers (Basel) ; 13(16)2021 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-34439399

RESUMEN

In recent decades, adoptive cell transfer and checkpoint blockade therapies have revolutionized immunotherapeutic approaches to cancer treatment. Advances in whole exome/genome sequencing and bioinformatic detection of tumour-specific genetic variations and the amino acid sequence alterations they induce have revealed that T cell mediated anti-tumour immunity is substantially directed at mutated peptide sequences, and the identification and therapeutic targeting of patient-specific mutated peptide antigens now represents an exciting and rapidly progressing frontier of personalized medicine in the treatment of cancer. This review outlines the historical identification and validation of mutated peptide neoantigens as a target of the immune system, and the technical development of bioinformatic and experimental strategies for detecting, confirming and prioritizing both patient-specific or "private" and frequently occurring, shared "public" neoantigenic targets. Further, we examine the range of therapeutic modalities that have demonstrated preclinical and clinical anti-tumour efficacy through specifically targeting neoantigens, including adoptive T cell transfer, checkpoint blockade and neoantigen vaccination.

11.
Clin Transl Immunology ; 10(5): e1283, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33976881

RESUMEN

OBJECTIVES: The increasing success of Chimeric Antigen Receptor (CAR) T cell therapy in haematological malignancies is reinvigorating its application in many other cancer types and with renewed focus on its application to solid tumors. We present a novel CAR against glioblastoma, an aggressive, malignant glioma, with a dismal survival rate for which treatment options have remained unchanged for over a decade. METHODS: We use the human Retained Display (ReD) antibody platform (Myrio Therapeutics) to identify a novel single-chain variable fragment (scFv) that recognises epidermal growth factor receptor mutant variant III (EGFRvIII), a common and tumor-specific mutation found in glioblastoma. We use both in vitro functional assays and an in vivo orthotopic xenograft model of glioblastoma to examine the function of our novel CAR, called GCT02, targeted using murine CAR T cells. RESULTS: Our EGFRvIII-specific scFv was found to be of much higher affinity than reported comparators reverse-engineered from monoclonal antibodies. Despite the higher affinity, GCT02 CAR T cells kill equivalently but secrete lower amounts of cytokine. In addition, GCT02-CAR T cells also mediate rapid and complete tumor elimination in vivo. CONCLUSION: We present a novel EGFRvIII-specific CAR, with effective antitumor functions both in in vitro and in a xenograft model of human glioblastoma.

12.
J Med Chem ; 63(5): 2282-2291, 2020 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-31418565

RESUMEN

Cancer immunotherapy has gained increasing attention due to its potential specificity and lack of adverse side effects when compared to more traditional modes of treatment. Toll-like receptor 2 (TLR2) agonists are lipopeptides possessing the S-[2,3-bis(palmitoyloxy)propyl]-l-cysteine (Pam2Cys) motif and exhibit potent immunostimulatory effects. These agonists offer a means of providing "danger signals" in order to activate the immune system toward tumor antigens. Thus, the development of TLR2 agonists is attractive in the search of potential immunostimulants for cancer. Existing SAR studies of Pam2Cys with TLR2 indicate that the structural requirements for activity are, for the most part, very intolerable. We have investigated the importance of stereochemistry, the effect of N-terminal acylation, and homologation between the two ester functionalities in Pam2Cys-conjugated lipopeptides on TLR2 activity. The R diastereomer is significantly more potent than the S diastereomer and N-terminal modification generally lowers TLR2 activity. Most notably, homologation gives rise to analogues which are comparatively active to the native Pam2Cys containing constructs.


Asunto(s)
Adyuvantes Inmunológicos/química , Adyuvantes Inmunológicos/farmacología , Lipopéptidos/química , Lipopéptidos/farmacología , Receptor Toll-Like 2/agonistas , Adyuvantes Inmunológicos/síntesis química , Vacunas contra el Cáncer/farmacología , Cisteína/análogos & derivados , Cisteína/síntesis química , Cisteína/farmacología , Humanos , Lipopéptidos/síntesis química , Neoplasias/prevención & control , Estereoisomerismo , Receptor Toll-Like 2/metabolismo
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