Dataset Information

Weak protein interactions and pH- and temperature-dependent aggregation of human Fc1.

ABSTRACT: The Fc (fragment crystallizable) is a common structural region in immunoglobulin gamma (IgG) proteins, IgG-based multi-specific platforms, and Fc-fusion platform technologies. Changes in conformational stability, protein-protein interactions, and aggregation of NS0-produced human Fc1 were quantified experimentally as a function of pH (4 to 6) and temperature (30 to 77 °C), using a combination of differential scanning calorimetry, laser light scattering, size-exclusion chromatography, and capillary electrophoresis. The Fc1 was O-glycosylated at position 3 (threonine), and confirmed to correspond to the intact IgG1 by comparison with Fc1 produced by cleavage of the parent IgG1. Changing the pH caused large effects for thermal unfolding transitions, but it caused surprisingly smaller effects for electrostatic protein-protein interactions. The aggregation behavior was qualitatively similar across different solution conditions, with soluble dimers and larger oligomers formed in most cases. Aggregation rates spanned approximately 5 orders of magnitude and could be divided into 2 regimes: (i) Arrhenius, unfolding-limited aggregation at temperatures near or above the midpoint-unfolding temperature of the CH2 domain; (ii) a non-Arrhenius regime at lower temperatures, presumably as a result of the temperature dependence of the unfolding enthalpy for the CH2 domain. The non-Arrhenius regime was most pronounced for lower temperatures. Together with the weak protein-protein repulsions, these highlight challenges that are expected for maintaining long-term stability of biotechnology products that are based on human Fc constructs.

SUBMITTER: Wu H

PROVIDER: S-EPMC4966490 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Weak protein interactions and pH- and temperature-dependent aggregation of human Fc1.

Wu Haixia H Truncali Kristopher K Ritchie Julie J Kroe-Barrett Rachel R Singh Sanjaya S Robinson Anne S AS Roberts Christopher J CJ

mAbs 20150812 6

The Fc (fragment crystallizable) is a common structural region in immunoglobulin gamma (IgG) proteins, IgG-based multi-specific platforms, and Fc-fusion platform technologies. Changes in conformational stability, protein-protein interactions, and aggregation of NS0-produced human Fc1 were quantified experimentally as a function of pH (4 to 6) and temperature (30 to 77 °C), using a combination of differential scanning calorimetry, laser light scattering, size-exclusion chromatography, and capilla ...[more]

PMID: 26267255

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Project description:BackgroundWeak acids, such as acetic acid, show virucidal effects against viruses, and disinfectants are considered effective virucidal agents possibly because of their low pH, depending on the proton concentration. This study aimed to evaluate the efficacy of different weak acids (acetic, oxalic, and citric acids) and eligible vinegars under different pH conditions by comparing their inactivation efficacies against enveloped and non-enveloped viruses.MethodsAcetic, oxalic, and citric acids were adjusted to pH values of 2, 4 and 6, respectively. They were also diluted from 1 M to 0.001 M with distilled water. Enveloped influenza A virus (FulV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and non-enveloped feline calicivirus (FCV) were treated with adjusted weak acids for up to 30 min. These viruses were also reacted with white distilled vinegar (WDV) and grain-flavored distilled vinegar (GV) for up to 30 min. Infectious viral titers after the reactions were expressed as plaque-forming units per mL.ResultsAcetic acid showed virucidal effects against FulV at pH 4, whereas citric and oxalic acids did not. Acetic and citric acids inactivated SARS-CoV-2 at pH 2, whereas oxalic acid did not. All acids showed virucidal effects against FVC at pH 2; however, not at pH 4. The virucidal effects of the serially diluted weak acids were also reflected in the pH-dependent results. WDV and GV significantly reduced FulV titers after 1 min. SARS-CoV-2 was also susceptible to the virucidal effects of WDV and GV; however, the incubation period was extended to 30 min. In contrast, WDV and GV did not significantly inactivate FCV.ConclusionsThe inactivation efficacy of weak acids is different even under the same pH conditions, suggesting that the virucidal effect of weak acids is not simply determined by pH, but that additional factors may also influence these effects. Moreover, eligible vinegars, the main component of which is acetic acid, may be potential sanitizers for some enveloped viruses, such as FulV, in the domestic environment.

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Dataset Information

Weak protein interactions and pH- and temperature-dependent aggregation of human Fc1.

Publications

Weak protein interactions and pH- and temperature-dependent aggregation of human Fc1.

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