Asunto(s)
Citometría de Flujo/tendencias , Análisis de la Célula Individual/métodos , Aptámeros de Nucleótidos , Biomarcadores , Bases de Datos como Asunto , Citometría de Flujo/instrumentación , Citometría de Flujo/normas , Genómica , Humanos , Espectrometría de Masas/instrumentación , Espectrometría de Masas/métodos , Microbiota/genética , Microscopía Fluorescente , Reproducibilidad de los Resultados , Programas Informáticos , Estudios de Validación como AsuntoRESUMEN
AIMS: This paper describes the pharmacological findings from a study where otelixizumab, an anti-CD3É mAb, was dosed in new onset Type 1 diabetes mellitus (NOT1DM) patients. This is the first time that the full dose-response of an anti-CD3É mAb has been investigated in the clinic. The data have been validated using a previously developed pharmacokinetic/pharmacodynamic (PK/PD) model of otelixizumab to simulate the interplay between drug administration, CD3É target engagement and downmodulation. METHODS: Patients were randomized to control or active treatment with otelixizumab (1:4), administered via infusion over 6 days, in a dose-ascending study consisted of three cohorts (n = 10 per cohort) at doses of 9, 18 or 27 mg respectively. The study allowed quantification of otelixizumab PK, CD3É target engagement and its pharmacodynamic effect (CD3ε/TCR modulation on circulating T lymphocytes). RESULTS: Otelixizumab concentrations increased and averaged to 364.09 (54.3), 1625.55 (72.5) and 2781.35 (28.0) ng ml-1 (Geom.mean, %CV) at the 9, 18 and 27 mg dose respectively. CD3É target engagement was found to be rapid (within the first 30 min), leading to a receptor occupancy of ~60% within 6 h of dosing in all three doses. A dose-response relationship was observed with the two highest doses achieving a ~90% target engagement and consequential CD3É/TCR downmodulation by Day 6. CONCLUSIONS: Data from this study revealed maximum target engagement and CD3É/TCR modulation is achieved at doses of 18, 27 mg of otelixizumab. These findings can be useful in guiding dose selection in clinical trials with anti-CD3É mAbs.
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Anticuerpos Monoclonales Humanizados/administración & dosificación , Complejo CD3/antagonistas & inhibidores , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T/efectos de los fármacos , Adolescente , Adulto , Anticuerpos Monoclonales Humanizados/farmacocinética , Complejo CD3/inmunología , Complejo CD3/metabolismo , Diabetes Mellitus Tipo 1/inmunología , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Infusiones Intravenosas , Masculino , Terapia Molecular Dirigida/métodos , Receptores de Antígenos de Linfocitos T/inmunología , Linfocitos T/inmunología , Linfocitos T/metabolismo , Resultado del Tratamiento , Adulto JovenRESUMEN
Flow cytometry is increasingly recognized as an invaluable technology in biomarker research. Owing to its multiparametric nature it can provide highly detailed information on any single cell in a heterogeneous population. Its versatility means it can be conducted in both the preclinical and clinical setting, generating biomarker data that can drive decisions pertaining to dose selection in clinical trials, treatment options for cancer sufferers and even suitability of patients to receive transplants. Most tissue types can be utilized by the flow cytometrist, allowing the technology to be applied to many fields of research, yet consensus still needs to be reached on standardization, regulation and validation of multiparametric flow cytometry assays. In parallel, continual innovation in analysis software to manage the huge datasets that can be generated is also needed. Nevertheless, the flexibility of flow cytometry means that it remains at the forefront of both routine and exploratory biomarker studies.
Asunto(s)
Biomarcadores/metabolismo , Citometría de Flujo , Ciclo Celular , Análisis por Conglomerados , Citocinas/metabolismo , Humanos , Inmunofenotipificación , Linfocitos T/metabolismoRESUMEN
Image-based screening, a new and flexible tool in the drug discovery cascade, is amenable to many different targets. This article describes a particular use of the Cellomics ArrayScan in developing a functional screen for histamine H(4) receptor (H(4)R) antagonists that have potential utility in inflammatory diseases of the airways such as asthma, with H(4)R being expressed on a wide variety of immune cells including eosinophils. Exposure to histamine causes eosinophils to migrate from the bloodstream into the tissue where they contribute to inflammation. Migration is manifested through rearrangements of the actin cytoskeleton and phalloidin, a biological peptide, selectively binds F-actin over G-actin and can be used to detect these cytoskeletal changes mediating inflammatory function. A fluorescent conjugate of phalloidin was used to visualize histamine-induced actin polymerization in human eosinophils on the Cellomics ArrayScan. Inhibition of this phenomenon by commercially available histamine receptor antagonists was measured. The selective H(4)R antagonist JNJ7777120 inhibited histamine-induced actin polymerization in eosinophils most potently. This assay illustrates that this phenomenon is mediated through the H(4)R and that the image-based format has enhanced screening utility for identifying selective H(4)R antagonists over traditional flow cytometry methods.