Article
Posttraumatic functional abnormalities in neutrophils and monocytes are caused by their phenotypic shift of three different subsets
Search Medline for
Authors
-
Andrea Janicová
- Klinik für Radiologie und Nuklearmedizin, OvGU, Magdeburg, Magdeburg, Germany
-
Baolin Xu
- Otto-von-Guericke University Magdeburg, Radiologie, Magdeburg, Germany
-
Florian Haag
- Klinik für Radiologie und Nuklearmedizin, OvGU, Magdeburg, Magdeburg, Germany
-
Frank Hildebrand
- Klinik für Unfall- und Wiederherstellungschirurgie, Universitätsklinik der RWTH Aachen, Aachen, Germany
-
Ingo Marzi
- Johann Wolfgang Goethe Universität Frankfurt am Main, Klinik für Unfall-, Hand- und Wiederherstellungschirurgie, Frankfurt am Main, Germany
-
Philipp Störmann
- Johann Wolfgang Goethe Universität Frankfurt am Main, Klinik für Unfall-, Hand- und Wiederherstellungschirurgie, Frankfurt am Main, Germany
-
Borna Relja
- Otto-von-Guericke University Magdeburg, Magdeburg, Germany
| Published: | October 26, 2021 |
|---|
Outline
Text
Objectives: Major trauma has been associated with a high vulnerability for the development of secondary infections caused by an imbalanced immune response. Monocytes and neutrophils, as the first immune cells recruited to the site of infection, are subdivided into three different subsets according their CD16/CD14 and CD16/CD62L surface expression, with possible different but yet not clearly defined functions. Here, we evaluated the dynamic phenotypic changes of monocyte and neutrophil subsets as well as their levels of reactive oxygen species (ROS) and the phagocytic capacity in severely injured patients.
Methods: Peripheral blood was withdrawn from severely injured trauma patients (TP; n = 15, ISS > 16) within 24 hours post-injury and from healthy volunteers (HV). The biomaterial was stained for CD16 and CD14 or CD16 and CD62L, respectively. CD14brightCD16- (classical), CD14brightCD16+ (intermediate) and CD14dimCD16+ (non-classical) monocyte subsets and CD16dimCD62Lbright (immature), CD16brightCD62Lbright (mature) and CD16brightCD62Ldim (aged) neutrophil subsets were evaluated by flow cytometry. Subsequently, subset-specific ROS production and phagocytosis were analysed.
Results and Conclusion: Following major trauma, the classical and non-classical monocyte population became less abundant, whereas the intermediate monocyte counts significantly increased compared to HV. ROS levels significantly increased in all monocyte subsets. The numbers of immature neutrophils significantly increased in injured patients. The mature and aged neutrophil levels remained unchanged but those neutrophils displayed significantly increased ROS production. Whereas major trauma did not affect the counts of phagocytosis+ neutrophils in all subsets, they showed higher phagocytic capacity per cell.
Monocytes and neutrophils display a phenotypic shift very early after major trauma. Increased functional abnormalities of certain subsets may contribute to the imbalanced immune response and dampened antimicrobial function and thus, may represent a potential therapeutic target. Further studies on isolated subsets are necessary to evaluate their physiological role after trauma.
