Escherichia coli-induced inflammatory responses are temperature-dependent in human whole blood ex vivo.
Mol Immunol
; 157: 70-77, 2023 05.
Article
em En
| MEDLINE
| ID: mdl-37001293
ABSTRACT
Systemic inflammatory conditions are often associated with hypothermia or hyperthermia. Therapeutic hypothermia is used in post-cardiac arrest and some other acute diseases. There is a need for more knowledge concerning the effect of various temperatures on the acute inflammatory response. The complement system plays a crucial role in initiating the inflammatory response. We hypothesized that temperatures above and below the physiologic 37 °C affect complement activation and cytokine production ex vivo. Lepirudin-anticoagulated human whole blood from 10 healthy donors was incubated in the presence or absence of Escherichia coli at different temperatures (4 °C, 12 °C, 20 °C, 33 °C, 37 °C, 39 °C, and 41 °C). Complement activation was assessed by the terminal C5b-9 complement complex (TCC) and the alternative convertase C3bBbP using ELISA. Cytokines were measured using a 27-plex assay. Granulocyte and monocyte activation was evaluated by CD11b surface expression using flow cytometry. A consistent increase in complement activation was observed with rising temperature, reaching a maximum at 41 °C, both in the absence (C3bBbP p < 0.05) and presence (C3bBbP p < 0.05 and TCC p < 0.05) of E. coli. Temperature alone did not affect cytokine production, whereas incubation with E. coli significantly increased cytokine levels of IL-1ß, IL-2, IL-6, IL-8, IFN-γ, and TNF at temperatures > 20 °C. Maximum increase occurred at 39 °C. However, a consistent decrease was observed at 41 °C, significant for IL-1ß (p = 0.003). Granulocyte CD11b displayed the same temperature-dependent pattern as cytokines, with a corresponding increase in endothelial cell apoptosis and necrosis. Thus, blood temperature differentially determines the degree of complement activation and cytokine release.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Citocinas
/
Escherichia coli
Limite:
Humans
Idioma:
En
Revista:
Mol Immunol
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Noruega