Capillary electrophoresis-sodium dodecyl sulfate (CE-SDS) is a common analytical procedure used to quantitate critical quality attributes relating to the purity and glycosylation of monoclonal antibodies (mAbs). In this study, the application of an Analytical Quality by Design framework incorporating Design of Experiments was used to develop and validate both non-reduced (CE-NR) and reduced (CE-R) versions of this analytical procedure. Formal risk assessments were used to identify critical method attributes for optimization based on their potential impacts to performance criteria outlined in an analytical target profile.
View Article and Find Full Text PDFJ Chromatogr B Analyt Technol Biomed Life Sci
July 2024
Protein A (ProA) high-performance liquid chromatography (HPLC) is a common analytical procedure for measuring monoclonal antibody (mAb) titers due to its high specificity and efficiency. Accurate and reliable results of this procedure are imperative, as the quantitation of the total mAb present for in-process samples directly impacts downstream purification steps related to the removal of process-related impurities. This study aimed to improve a platform ProA HPLC analytical procedure which was previously developed using traditional approaches and was not always reliable.
View Article and Find Full Text PDFThis work presents the application of AQbD principles to the development of a size exclusion chromatography (SEC) HPLC procedure for the determination of monoclonal antibody (mAb) product purity using state-of-the-art column technology available via the Waters™ XBridge Premier Protein SEC column. Analytical Quality by Design (AQbD) emphasizes a systematic, risk-based lifecycle approach to analytical procedure development based on sound statistical methodologies. It has recently become increasingly recommended by regulatory agencies as a response to the need for greater efficiency, improved reliability, and increased robustness among modern analytical procedures in the pharmaceutical industry.
View Article and Find Full Text PDFJ Chromatogr B Analyt Technol Biomed Life Sci
March 2024
The complex structure of biopharmaceutical products poses an inherent need for their thorough characterization to ensure product quality, safety, and efficacy. Analytical size exclusion chromatography (SEC) is a widely used technique throughout the development and manufacturing of monoclonal antibodies (mAbs) which quantifies product size variants such as aggregates and fragments. Aggregate and fragment content are critical quality attributes (CQAs) in mAb products, as higher contents of such size heterogeneities impact product quality.
View Article and Find Full Text PDFBackground: Although children can frequently experience a cough that affects their quality of life, few epidemiological studies have explored cough without a cold during childhood.
Objectives: The objective of the study was to describe the latent class trajectories of cough from one to 10 years old and analyse their association with wheezing, atopy and allergic diseases.
Methods: Questions about cough, wheeze and allergic diseases were asked at 1, 1.
Studies with Wilson disease model mice that accumulate excessive copper, due to a dysfunctional ATP7B "copper pump" resulting in decreased biliary excretion, showed that the compensatory increase in urinary copper loss was due to a small copper carrier (∼1 kDa) (SCC). We show here that SCC is also present in the blood plasma of normal and Wilson disease model mice and dogs, as determined by ultrafiltration and size exclusion chromatography (SEC). It is secreted by cultured hepatic and enterocytic cells, as determined by pretreatment with 67Cu nitrilotriacetate (NTA) or nonradioactive 5-10 μM Cu-NTA, and collecting and examining 3 kDa ultrafiltrates of the conditioned media, where a single major copper peak is detected by SEC.
View Article and Find Full Text PDFObjectives: Lumacaftor-ivacaftor is a cystic fibrosis transmembrane conductance regulator (CFTR) modulator known to improve clinical status in people with cystic fibrosis (CF). The aim of this study was to assess lung structural changes after 1 year of lumacaftor-ivacaftor treatment and to use unsupervised machine learning to identify morphological phenotypes of lung disease that are associated with response to lumacaftor-ivacaftor.
Methods: Adolescents and adults with CF from a French multicentre real-world prospective observational study evaluating the first year of treatment with lumacaftor-ivacaftor were included if they had pre-therapeutic and follow-up chest computed tomography (CT) scans available.
Lung damage in cystic fibrosis (CF) is strongly associated with lower airway infections. Early treatment of is recommended. Pathogen detection requires sampling of lower airway secretions, which remains a challenge in nonexpectorating patients.
View Article and Find Full Text PDFThe relation between co- and post-translational protein folding and aggregation in the cell is poorly understood. Here, we employ a combination of fluorescence anisotropy decays in the frequency domain, fluorescence-detected solubility assays, and NMR spectroscopy to explore the role of the ribosome in protein folding within a biologically relevant context. First, we find that a primary function of the ribosome is to promote cotranslational nascent-protein solubility, thus supporting cotranslational folding even in the absence of molecular chaperones.
View Article and Find Full Text PDFThe heat-shock factor Hsp70 and other molecular chaperones play a central role in nascent protein folding. Elucidating the task performed by individual chaperones within the complex cellular milieu, however, has been challenging. One strategy for addressing this goal has been to monitor protein biogenesis in the absence and presence of inhibitors of a specific chaperone, followed by analysis of folding outcomes under both conditions.
View Article and Find Full Text PDFHypersensitivity pneumonitis (HP) is an interstitial lung disease caused by an immune response to a variety of antigens to which patients have been previously sensitised. It can occur at any age. In children, it is a rare disease, probably under-diagnosed, with an estimated prevalence of 4 per million.
View Article and Find Full Text PDFPseudomonas aeruginosa is the main cause of chronic airway infection in cystic fibrosis (CF). However, for unclear reasons some patients are never colonized by P. aeruginosa.
View Article and Find Full Text PDFBackground: The effect of exposure to microorganisms on allergic diseases has been well studied. The protective effect of early food diversity against allergic diseases was previously shown in the PASTURE cohort study. The consumption of cheese, a food potentially rich in microbial diversity, deserves further examination.
View Article and Find Full Text PDFAnfinsen's thermodynamic hypothesis does not explicitly take into account the possibility of protein aggregation. Here, we introduce a cyclic-perturbation approach to prove that not only the native state but also soluble aggregates of most proteins can be highly populated under mild, physiologically relevant conditions, even at very low concentration. Surprisingly, these aggregates are not necessarily amyloid in nature and are usually not observed in bioactive proteins due to the extremely low kinetic flux from the native state toward a region of the chemical-potential landscape encoding aggregates.
View Article and Find Full Text PDFImportance: Atopic dermatitis is an inflammatory, pruritic skin disease that often occurs in early infancy with a chronic course. However, a specific description of subtypes of atopic dermatitis depending on the timing of onset and progression of the disease in childhood is lacking.
Objective: To identify different phenotypes of atopic dermatitis using a definition based on symptoms before age 6 years and to determine whether some subtypes are more at risk for developing other allergic diseases.
Unlabelled: Respiratory syncytial virus (RSV) infections may worsen cystic fibrosis (CF) lung disease and favor Pseudomonas aeruginosa (Pa) or Staphylococcus aureus (Sa) acquisition, which is of particular importance in the youngest patients. We aimed to determine the effectiveness of PVZ on microbiological outcomes in young children with CF. We conducted a retrospective case-control study to compare these outcomes in children who systematically received PVZ (PVZ+; n = 40) or not (PVZ-; n = 140).
View Article and Find Full Text PDFBackground: Accurate assessment of atopic sensitization is pivotal to clinical practice and research. Skin prick test (SPT) and specific IgE (sIgE) are often used interchangeably. Some studies have suggested a disagreement between these two methods, and little is known about their association with allergic diseases.
View Article and Find Full Text PDFInt Arch Allergy Immunol
February 2017
Background: Accurate diagnosis of allergic sensitization is essential in clinical practice and allergy research, and the choice of assessment method may have an important impact. The PASTURE study (Protection against Allergy: Study of Rural Environment) examines the influence of exposure to a dairy farm environment on the occurrence of allergy in a cohort of rural European children from birth to 10 years. The aim of our study was to analyze agreement between skin prick tests (SPTs), to aeroallergens and food allergens, and specific IgE and to evaluate the association of SPT with atopic dermatitis in the 204 French children of the PASTURE study.
View Article and Find Full Text PDFBackground And Aims: Catheter venous thrombosis may result in life-threatening embolic complications. Recently, a thrombophilic tendency was described in cystic fibrosis (CF), the significance of which remains unclear. The aims of this study were to (1) document the frequency of catheter venous thrombosis detected by colour-Doppler-ultrasound (Doppler-US), (2) assess genetic and acquired thrombophilia risk factors for catheter venous thrombosis and hypercoagulability status and (3) provide recommendations on laboratory screening when considering insertion of a totally implantable vascular access device (TIVAD) in CF patients.
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