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1.
Artículo en Alemán | MEDLINE | ID: mdl-38656348

RESUMEN

BACKGROUND AND AIM: Heat and heavy rain can have negative health impacts for people in Germany. Vulnerable groups in particular, such as children and the elderly, are at increased risk and require special precautions. This paper examines how employers of the municipal administration and facilitating organisations perceive the risk of heat and heavy rain for daycare centres and care facilities, and to what extent an exchange takes place between the municipal level and the facilities. In addition, specially developed information materials with recommendations for action for adapting to heat and heavy rain that are aimed at such facilities were evaluated. METHODS: In the summer of 2021, we conducted a quantitative survey. A total of 333 respondents from municipal administrations, facilitating organisations and institutions participated. Descriptive analyses and ANOVAs were conducted. RESULTS: Risk perception and adaptation knowledge concerning heat was perceived higher than concerning heavy rain. The intention to support institutions in finding measures for adaptation was also higher with regard to heat. The majority of interviewees from municipal administrations and institutions communicated with institutions through various channels on different topics including the natural hazards mentioned. The information material was evaluated positively. DISCUSSION: This article shows that facilities are seen as very affected by heat waves. Awareness towards heavy rainfall needs to be raised. The feedback on the information material clearly shows a high need in this area.

2.
Risk Anal ; 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38321845

RESUMEN

Extreme heat poses severe health threats, as the increased numbers of hospitalizations and fatalities during heat waves show, though little is known about adaptive behavior toward heat. We conducted a household survey on individual perceptions of heat stress and individual heat protection in the summer and autumn of 2019. In total, 1417 people from three medium-sized German cities participated via telephone or online. Based on the Protective Action Decision Model (PADM), which we adapted to heat stress, we analyzed links between risk perception, environmental and demographic factors, perceptions of stakeholders, different heat warning messages, as well as actual and intended adaptive behavior. Overall, the PADM constructs explained around 16% of the variance in protection motivation, 19% in protective response, and 23% in emotion-focused coping. Context factors (i.e., temperature, risk communication, gender, age, and homeownership) were significant predictors of the addressed outcome variables as were psychological factors (i.e., perceived personal vulnerability, response efficacy, response costs, preparedness, and perceived external responsibility). We further explored the effect of different warning messages on situational knowledge and intended behavioral adaptation in an experimental setting. Results showed that respondents felt significantly better informed after receiving a warning with action recommendations and reported more intended specific behaviors. Our research gives insights into individual protective action decision-making processes. Based on our findings, we recommend tailoring risk communication strategies and combining heat warnings with action recommendations whenever possible to increase understanding and individual adaptation.

3.
MAbs ; 15(1): 2175312, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36799476

RESUMEN

The development of increasingly complex antibody formats, such as bispecifics, can lead to the formation of increasingly complex high- and low-molecular-weight by-products. Here, we focus on the characterization of high molecular weight species (HMWs) representing the highest complexity of size variants. Standard methods used for product release, such as size exclusion chromatography (SEC), can separate HMW by-products from the main product, but cannot distinguish smaller changes in mass. Here, for the identification of the diverse and complex HMW variants of a trivalent bispecific CrossMAb antibody, offline fractionation, as well as production of HMW by-products combined with comprehensive analytical testing, was applied. Furthermore, HMW variants were analyzed regarding their chemical binding nature and tested in functional assays regarding changes in potency of the variants. Changes in potency were explained by detailed characterization using mass photometry, SDS-PAGE analysis, native mass spectrometry (MS) coupled to SEC and bottom-up proteomics. We identified a major portion of the HMW by-products to be non-covalently linked, leading to dissociation and changes in activity. We also identified and localized high heterogeneity of a by-product of concern and applied a CD3 affinity column coupled to native MS to annotate unexpected by-products. We present here a multi-method approach for the characterization of complex HMW by-products. A better understanding of these by-products is beneficial to guide analytical method development and proper specification setting for therapeutic bispecific antibodies to ensure constant efficacy and patient safety of the product through the assessment of by-products.


Asunto(s)
Anticuerpos Biespecíficos , Humanos , Anticuerpos Biespecíficos/química , Peso Molecular , Espectrometría de Masas/métodos , Cromatografía en Gel
4.
J Am Soc Mass Spectrom ; 32(8): 2062-2071, 2021 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-33687195

RESUMEN

The aim of this study was to characterize the product variants of a therapeutic T-cell bispecific humanized monoclonal antibody (TCB Mab, ∼200 kDa, asymmetric) and to develop an online cation-exchange chromatography native electrospray mass spectrometry method (CEC-UV-MS) for direct TCB Mab charge variant monitoring during bioprocess and formulation development. For the identification and functional evaluation of the diverse and complex TCB Mab charge variants, offline fractionation combined with comprehensive analytical testing was applied. The offline fractionation of abundant product variant peaks enabled identification of coeluting acid charge variants such as asparagine deamidation, primary and secondary Fab glycosylation (with and without sialic acid), and the presence of O-glycosylation in the G4S-linker region. Consequently, a new nonconsensus N-glycosylation motif (N-338-FG) in the heavy chain CDR region was discovered. Functional evaluation by cell-based potency testing demonstrated a clear and negative impact of both asparagine deamidations, whereas the O-glycosylation did not affect the TCB Mab biological activity. We established an online native CEC-UV-MS method, with an ammonium acetate buffer and pH gradient, to directly monitor the TCB Mab charge variants. All abundant chemical degradations and post-translational amino acid modifications already identified by offline fraction experiments and liquid chromatography mass spectrometry peptide mapping could also be monitored by the online CEC-UV-MS method. The herein reported online native CEC-UV-MS methodology represents a complementary or even alternative approach for multiattribute monitoring of biologics, offering multiple benefits, including increased throughput and reduced sample handling and intact protein information in the near-native state.


Asunto(s)
Anticuerpos Monoclonales/análisis , Anticuerpos Monoclonales/química , Cromatografía por Intercambio Iónico/métodos , Espectrometría de Masa por Ionización de Electrospray/métodos , Anticuerpos Monoclonales/metabolismo , Cationes , Regiones Determinantes de Complementariedad , Glicosilación , Fragmentos Fab de Inmunoglobulinas/análisis , Fragmentos Fab de Inmunoglobulinas/química , Fragmentos Fab de Inmunoglobulinas/metabolismo , Mapeo Peptídico/métodos , Rayos Ultravioleta
5.
MAbs ; 11(7): 1191-1196, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31276431

RESUMEN

Determination of the impact of individual antibody glycoforms on FcɣRIIIa affinity, and consequently antibody-dependent cell-mediated cytotoxicity (ADCC) previously required high purity glycoengineering. We hyphenated FcɣRIIIa affinity chromatography to mass spectrometry, which allowed direct affinity comparison of glycoforms of intact monoclonal antibodies. The approach enabled reproduction and refinement of known glycosylation effects, and insights on afucosylation pairing as well as on low-abundant, unstudied glycoforms. Our method greatly improves the understanding of individual glycoform structure-function relationships. Thus, it is highly relevant for assessing Fc-glycosylation critical quality attributes related to ADCC.


Asunto(s)
Anticuerpos Monoclonales/metabolismo , Fragmentos Fc de Inmunoglobulinas/metabolismo , Inmunoglobulina G/metabolismo , Receptores de IgG/metabolismo , Anticuerpos Monoclonales/química , Afinidad de Anticuerpos , Citotoxicidad Celular Dependiente de Anticuerpos , Cromatografía de Afinidad , Glicosilación , Humanos , Fragmentos Fc de Inmunoglobulinas/química , Inmunoglobulina G/química , Espectrometría de Masas , Polisacáridos/química , Relación Estructura-Actividad
6.
Anal Chem ; 89(10): 5404-5412, 2017 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-28398745

RESUMEN

We report on the online coupling of FcRn affinity liquid chromatography (LC) with electrospray ionization mass spectrometry (ESI-MS) in native conditions to study the influence of modifications on the interaction of recombinant mAbs with the immobilized FcRn receptor domain. The analysis conditions were designed to fit the requirements of both affinity LC and ESI-MS. The mobile phase composition was optimized to maintain the proteins studied in native conditions and enable sharp pH changes in order to mimic properly IgGs Fc domain/FcRn receptor interaction. Mobile phase components needed to be sufficiently volatile to achieve native MS analysis. MS data demonstrated the conservation of the pseudonative form of IgGs and allowed identification of the separated variants. Native FcRn affinity LC-ESI-MS was performed on a therapeutic mAb undergoing various oxidation stress. Native MS detection was used to determine the sample oxidation level. Lower retention was observed for mAbs oxidized variants compared to their intact counterparts indicating decreased affinities for the receptor. This methodology proved to be suitable to identify and quantify post-translational modifications at native protein level in order to correlate their influence on the binding to the FcRn receptor. Native FcRn affinity LC-ESI-MS can tremendously reduce the time required to assess the biological relevance of the IgG microheterogeneities thus providing valuable information for biopharmaceutical research and development.


Asunto(s)
Anticuerpos Monoclonales/metabolismo , Péptidos/análisis , Receptores Fc/metabolismo , Espectrometría de Masa por Ionización de Electrospray , Animales , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/genética , Cromatografía de Afinidad , Cromatografía Líquida de Alta Presión , Glicosilación , Concentración de Iones de Hidrógeno , Fragmentos Fc de Inmunoglobulinas/química , Fragmentos Fc de Inmunoglobulinas/metabolismo , Ratones , Mapeo Peptídico , Péptidos/aislamiento & purificación , Unión Proteica , Receptores Fc/química , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación
7.
MAbs ; 8(2): 331-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26655595

RESUMEN

High-molecular weight aggregates such as antibody dimers and other side products derived from incorrect light or heavy chain association typically represent critical product-related impurities for bispecific antibody formats. In this study, an approach employing ultra-pressure liquid chromatography size-exclusion separation combined with native electrospray ionization mass spectrometry for the simultaneous formation, identification and quantification of size variants in recombinant antibodies was developed. Samples exposed to storage and elevated temperature(s) enabled the identification of various bispecific antibody size variants. This test system hence allowed us to study the variants formed during formulation and bio-process development, and can thus be transferred to quality control units for routine in-process control and release analytics. In addition, native SEC-UV/MS not only facilitates the detailed analysis of low-abundant and non-covalent size variants during process characterization/validation studies, but is also essential for the SEC-UV method validation prior to admission to the market.


Asunto(s)
Anticuerpos Biespecíficos/química , Cromatografía en Gel , Agregado de Proteínas , Anticuerpos Biespecíficos/análisis
8.
MAbs ; 7(5): 891-900, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26000623

RESUMEN

Oxidation of methionine (Met) residues is one of several chemical degradation pathways for recombinant IgG1 antibodies. Studies using several methodologies have indicated that Met oxidation in the constant IgG1 domains affects in vitro interaction with human neonatal Fc (huFcRn) receptor, which is important for antibody half-life. Here, a completely new approach to investigating the effect of oxidative stress conditions has been applied. Quantitative ultra-performance liquid chromatography mass spectrometry (MS) peptide mapping, classical surface plasmon resonance and the recently developed FcRn column chromatography were combined with the new fast-growing approach of native MS as a near native state protein complex analysis in solution. Optimized mass spectrometric voltage and pressure conditions were applied to stabilize antibody/huFcRn receptor complexes in the gas phase for subsequent native MS experiments with oxidized IgG1 material. This approach demonstrated a linear correlation between quantitative native MS and IgG-FcRn functional analysis. In our study, oxidation of the heavy chain Met-265 resulted in a stepwise reduction of mAb3/huFcRn receptor complex formation. Remarkably, a quantitative effect of the heavy chain Met-265 oxidation on relative binding capacity was only detected for doubly oxidized IgG1, whereas IgG1 with only one oxidized heavy chain Met-265 was not found to significantly affect IgG1 binding to huFcRn. Thus, mono-oxidized IgG1 heavy chain Met-265 most likely does not represent a critical quality attribute for pharmacokinetics.


Asunto(s)
Antígenos de Histocompatibilidad Clase I/metabolismo , Inmunoglobulina G/metabolismo , Espectrometría de Masas/métodos , Oxidación-Reducción , Receptores Fc/metabolismo , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/metabolismo , Cromatografía Liquida , Humanos , Inmunoglobulina G/química , Mapeo Peptídico , Resonancia por Plasmón de Superficie
9.
MAbs ; 6(1): 185-96, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24135630

RESUMEN

The Fc glycosylation of therapeutic antibodies is crucial for their effector functions and their behavior in pharmacokinetics and pharmacodynamics. To monitor the Fc glycosylation in bioprocess development and characterization,high-throughput techniques for glycosylation analysis are needed. Here, we describe the development of a largely automated high-throughput glycosylation profiling method with multiplexing capillary-gel-electrophoresis (CGE) with laser induced fluorescence (LIF) detection using a DNA analyzer. After PNGaseF digestion, the released glycans were labeled with 9-aminopyrene-1,3,6-trisulfonic acid (APTS) in 96-well plates, which was followed by the simultaneous analysis of up to 48 samples. The peak assignment was conducted by HILIC-UPLC-MS/MS of the APTS-labeled glycans combined with peak fractionation and subsequent CGE-LIF analysis of the MS-characterized fractions. Quantitative data evaluation of the various IgG glycans was performed automatically using an in-house developed software solution. The excellent method accuracy and repeatability of the test system was verified by comparison with two UPLC-based methods for glycan analysis. Finally, the practical value of the developed method was demonstrated by analyzing the antibody glycosylation profiles from fermentation broths after small scale protein A purification.


Asunto(s)
Anticuerpos Monoclonales/química , Colorantes Fluorescentes/química , Inmunoglobulina G/química , Polisacáridos/química , Análisis de Secuencia de ADN/instrumentación , Programas Informáticos , Animales , Células CHO , Cricetinae , Cricetulus , Electroforesis Capilar , Glicosilación , Pirenos/química
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