gms | German Medical Science

Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2022)

25. - 28.10.2022, Berlin

PADI4 haplotype predisposes diabetics for delayed wound healing and wound infections by sensitizing neutrophils for neutrophil extracellular trap formation

Meeting Abstract

  • presenting/speaker Sabrina Ehnert - Siegfried Weller Institut für unfallmedizinische Forschung, Eberhard Karls Universität Tübingen, Tübingen, Germany
  • Philipp Hemmann - Berufsgenossenschaftliche Unfallklinik Tübingen, Klinik für Unfall- und Wiederherstellungschirurgie, Eberhard Karls Universität Tübingen, Tübingen, Germany
  • Christoph Ihle - Universität Tübingen, Berufsgenossenschaftliche Unfallklinik Tübingen, Klinik für Unfall- und Wiederherstellungschirurgie, Tübingen, Germany
  • Caren Linnemann - Siegfried Weller Institut für unfallmedizinische Forschung, Eberhard Karls Universität Tübingen, Tübingen, Germany
  • Jonas Mück - Siegfried Weller Institut für unfallmedizinische Forschung, Eberhard Karls Universität Tübingen, Tübingen, Germany
  • Tina Histing - Abteilung für Unfall- und Wiederherstellungschirurgie, BG Unfallklinik Tübingen, Eberhard Karls Universität Tübingen, Tübingen, Germany
  • Andreas Nüssler - Siegfried Weller Institut, Eberhard Karls Universität Tübingen, Unfallchirurgie, Tübingen, Germany

Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2022). Berlin, 25.-28.10.2022. Düsseldorf: German Medical Science GMS Publishing House; 2022. DocAB14-658

doi: 10.3205/22dkou030, urn:nbn:de:0183-22dkou0305

Veröffentlicht: 25. Oktober 2022

© 2022 Ehnert et al.
Dieser Artikel ist ein Open-Access-Artikel und steht unter den Lizenzbedingungen der Creative Commons Attribution 4.0 License (Namensnennung). Lizenz-Angaben siehe http://creativecommons.org/licenses/by/4.0/.


Gliederung

Text

Objectives: Following trauma and surgery circulating markers for neutrophil extracellular traps (NETs) are normally increased. In diabetic mice, it has been shown that massive accumulation of NETs in the scab causes delayed wound healing. Overexpression of peptidyl-arginine deiminase 4 (PADI4) in neutrophils was identified as key regulator in this process. For the human PADI4 gene different single nucleotide polymorphisms (SNPs) have been described, 3 of those SNPs (rs874881, rs11203366, rs11203367) comprise a haplotype associated with disease occurrence and severity in rheumatoid arthritis. This study aimed at investigating if diabetic patients show increased PADI4 expression in neutrophils and if this correlates with the PADI4 haplotype and wound healing.

Methods: Between 2018 and 2021, 530 patients (197 diabetics and 333 matched controls) hospitalized at a level 1 trauma center were enrolled in this study (Ethikvotum: 666/2018BO2). The clinical outcome was independently documented by 2 clinicians. Neutrophils were isolated by density gradient centrifugation from full blood sampled prior to surgery. PADI4 expression was determined by qRT-PCR. PADI4 SNPs were identified by ARMS-PCR. In vitro NET formation was determined by SYTOX-green assay, bioimpedance measurement, and immunofluorescent staining. Data were compared by Mann-Whitney or Chi-square test.

Results and conclusion: Diabetics showed significantly more complications than the matched controls (61.4% vs 28.2%, p<0.001). PADI4 expression in neutrophils was 9-fold higher (p<0.001) in diabetics than controls. This effect was even more pronounced (~11-fold increase, p<0.001) for diabetics that developed a wound infection or delayed wound healing. The PADI4 expression correlated with the PADI4 haplotype, with an average PADI4 expression highest for the minor variant (4.5-fold higher than the major variant, p=0.002). In line with this, neutrophils homozygous for the minor variant of PADI4 produced more rapidly a larger amount of NETs than neutrophils homozygous for the major variant of PADI4. Correlating the PADI4 haplotype with the clinical outcome revealed that diabetics with the minor PADI4 haplotype developed significantly more wound infections (66% vs 28%, p<0.001) and delayed wound healing (76% vs 45%, p=0.005) than diabetics with the major PADI4 haplotype. Interestingly, in controls, who had on average 21% wound infections and 20% delayed wound healing, no correlation between PADI4 haplotypes and clinical outcome was observed.

In summary, neutrophils from diabetics showed increased PADI4 expression, which correlated with the underlying PADI4 haplotype. This, in turn, sensitized neutrophils for increased NET formation. Interestingly, the PADI4 haplotype correlated with wound healing disturbance in diabetics. Thus, PADI4 haplotype may serve as a screening-marker to identify diabetics with an increased risk to develop wound infections and/or delayed wound healing.