Search

Multiple myeloma (MM) is a haematological malignancy characterised by the proliferation of clonal plasma cells in the bone marrow, usually leading to the secretion of a monoclonal immunoglobulin termed the M-protein. Multiple myeloma is a complex disease, and despite great advances in both detection and treatment of the disease, there remains a vast amount of interest in improving patient outcomes. In the era of novel agents and clinical trials, patients with MM are living longer and there is a requirement for frequent monitoring to assess treatment response and signs of relapse. Despite these improvements in treatment, even those patients achieving deep responses are still relapsing due to the presence of very low levels of residual disease, termed minimal residual disease (MRD). Increasingly sensitive techniques are needed to detect this MRD and, as MM is a bone marrow based disease, the majority of techniques focus on bone marrow based assays. However, as bone marrow sampling is invasive, painful and unpleasant for patients it is important to investigate whether blood-based assays could be equally or more informative of disease status. This project therefore aimed to obtain evidence as to whether blood-based assays can act as a safe and effective marker for disease in the bone marrow of treated multiple myeloma patients. Firstly, a bone marrow flow cytometry assay was validated to act as the gold standard technique. Next, three blood-based assays were investigated: circulating tumour plasma cell measurement, heavy/light chain measurement and mass spectrometry evaluation. This study shows the significance of blood-based assays at different disease stages in both transplant and nontransplant treated patients. These results lead to the suggestion of a testing algorithm focused on the addition of heavy/light chain measurement which can be pre-emptively used to influence decisions regarding bone marrow analysis and treatment, ultimately improving the patient experienc

The scientific and clinical interest in extracellular vesicles (EV) has grown exponentially during the past 15 years. As most research indicates that EVs can be utilised in diagnostics, prognostics and therapeutics, we may be on the brink of establishing the clinical utility of EV measurement, but how can we make this a reality? If we are to introduce EVs as biomarkers into clinical laboratories it will be necessary to offer fully validated, International Organization for Standardization (ISO) standard 15189 assays. ISO 15189 defines the quality management system requirements particular to medical laboratories and is used internationally to determine accreditation. In order for a clinical laboratory to offer an accredited test for EVs, this assay must have been subjected to a thorough assay validation process. This process requires the generation of data related to defined performance characteristics, to ensure that an assay is performing in accordance with the needs of its clinical users. Each of the defined performance characteristics will be discussed in this review, along with the issues that specifically affect EV analysis. Accreditation is increasingly important for all clinical laboratories and the standards required to achieve this are becoming more and more stringent. Therefore, as companies seek to develop the best assays to detect EVs and their molecular contents for clinical utility, and as we move rapidly towards our goal of offering EV analysis in the diagnosis and monitoring of disease, it is timely to highlight the requirements for the clinical accreditation of such assays. It is essential to consider these parameters to ensure that we develop the highest quality assays possible and ultimately the best outcomes for patients.

Rheumatoid Arthritis (RA) is a chronic, systemic autoimmune disease, primarily affecting the small joints of the hands, wrists and feet. Disease onset is insidious with classical symptoms including pain, morning stiffness, and persistent synovitis; accompanied by fatigue, malaise and weight loss. RA patients also suffer from a number of extra-articular manifestations and additional comorbidities, including rheumatoid nodules and scleritis; as well as an increased risk of cardiovascular disease (CVD), lymphoma and infection. Ultimately, RA is a devastatingly progressive disease, if a diagnosis and an effective therapeutic regimen is not established quickly. Identifying when a therapy is proving ineffective can be difficult, however, and is reliant upon accurate formal joint counts, CRP measurements and patient global assessments. These are potentially insensitive means of assessing remission and may result in delayed changes to therapeutic regimens. The identification of new biomarkers to improve the predictive value of these evaluation models would therefore greatly benefit patient care. Based upon current evidence, it has been hypothesized that RA patients who fail to make a clinical improvement following the initiation of csDMARD and bDMARD therapeutic regimens are identifiable by their profile of the following CD4+ T-cell populations: follicular helper, memory helper, antigen-specific and naturally-occurring regulatory CD4+ T-cells. As such, flow cytometric assays have developed for the identification and enumeration of these respective CD4+ T-cell populations; the relative and absolute counts of which were investigated within a cohort of healthy controls, with normal distributions established. Subsequently, we have identified distinct alterations to the CD4+ T-cell compartments of newly-diagnosed, treatment-naïve and longstanding RA patients, with clear associations with patient clinical outcomes observed. Of notable significance, the relative distribution of CC

BACKGROUND: Flow cytometry is the most commonly used technology to measure microvesicles (MVs). Despite reported limitations of this technique, MV levels obtained using conventional flow cytometry have yielded many clinically relevant findings, such as associations with disease severity and ability to predict clinical outcomes. This study aims to determine if MV enumeration by flow cytometry correlates with a measurement of their functional capacity, as this may explain how flow cytometry generates clinically relevant results. METHODS: one hundred samples from healthy individuals and patients with obstructive sleep apnoea were analysed by conventional flow cytometry (facscalibur) and by three functional mv assays: Zymuphen MP-activity in which data were given as phosphatidylserine equivalent, STA(®) Phospholipid Procoag Assay expressed as clotting time and Endogenous Thrombin Potential (ETP) reflecting in vitro thrombin generation. Correlations were determined by Spearman correlation. RESULTS: Absolute counts of lactadherin+ procoagulant MVs generated by flow cytometry weakly correlated with the results obtained from the Zymuphen MP-activity (r=0.5370, p<0.0001); correlated with ETP (r=0.7444, p<0.0001); negatively correlated with STA(®) Phospholipid Procoag Assay clotting time (-0.7872, p<0.0001), reflecting a positive correlation between clotting activity and flow cytometry. Levels of Annexin V+ procoagulant and platelet-derived MVs were also associated with functional assays. Absolute counts of MVs derived from other cell types were not correlated with the functional results. CONCLUSIONS: Quantitative results of procoagulant and platelet-derived MVs from conventional flow cytometry are associated with the functional capability of the MVs, as defined by three functional MV assays. Flow cytometry is a valuable technique for the quantification of MVs from different cellular origins; however, a combination of several analytical techniques may give the most comprehens

BACKGROUND: Travel to mountain areas is popular. However, the effects of acute exposure to moderate altitude on the cardiovascular system and metabolism are largely unknown. OBJECTIVES: To investigate the effects of acute exposure to moderate altitude on vascular function, metabolism and systemic inflammation. METHODS: In 51 healthy male subjects with a mean (SD) age of 26.9 (9.3) years, oxygen saturation, blood pressure, heart rate, arterial stiffness, lipid profiles, low density lipoprotein (LDL) particle size, insulin resistance (HOMA-index), highly-sensitive C-reactive protein and pro-inflammatory cytokines were measured at 490 m (Zurich) and during two days at 2590 m, (Davos Jakobshorn, Switzerland) in randomized order. The largest differences in outcomes between the two altitudes are reported. RESULTS: Mean (SD) oxygen saturation was significantly lower at 2590 m, 91.0 (2.0)%, compared to 490 m, 96.0 (1.0)%, p<0.001. Mean blood pressure (mean difference +4.8 mmHg, p<0.001) and heart rate (mean difference +3.3 bpm, p<0.001) were significantly higher at 2590 m, compared to 490 m, but this was not associated with increased arterial stiffness. At 2590 m, lipid profiles improved (median difference triglycerides -0.14 mmol/l, p=0.012, HDL +0.08 mmol/l, p<0.001, total cholesterol/HDL-ratio -0.25, p=0.001), LDL particle size increased (median difference +0.45 nm, p=0.048) and hsCRP decreased (median difference -0.18 mg/l, p=0.024) compared to 490 m. No significant change in pro-inflammatory cytokines or insulin resistance was observed upon ascent to 2590 m. CONCLUSIONS: Short-term stay at moderate altitude is associated with increased blood pressure and heart rate likely due to augmented sympathetic activity. Exposure to moderate altitude improves the lipid profile and systemic inflammation, but seems to have no significant effect on glucose metabolism. TRIAL REGISTRATION: ClinicalTrials.gov NCT01130948.

Late-phase clinical trials investigating metformin as a cancer therapy are underway. However, there remains controversy as to the mode of action of metformin in tumors at clinical doses. We conducted a clinical study integrating measurement of markers of systemic metabolism, dynamic FDG-PET-CT, transcriptomics, and metabolomics at paired time points to profile the bioactivity of metformin in primary breast cancer. We show metformin reduces the levels of mitochondrial metabolites, activates multiple mitochondrial metabolic pathways, and increases 18-FDG flux in tumors. Two tumor groups are identified with distinct metabolic responses, an OXPHOS transcriptional response (OTR) group for which there is an increase in OXPHOS gene transcription and an FDG response group with increased 18-FDG uptake. Increase in proliferation, as measured by a validated proliferation signature, suggested that patients in the OTR group were resistant to metformin treatment. We conclude that mitochondrial response to metformin in primary breast cancer may define anti-tumor effect.