CCR2 and DPP9 expression in the peripheral blood of COVID-19 patients: Influences of the disease severity and gender

Immunobiology. 2022 Mar;227(2):152184. doi: 10.1016/j.imbio.2022.152184. Epub 2022 Feb 1.


Introduction: Hyper-inflammatory reactions play a crucial role in the pathogenesis of the severe forms of COVID-19. However, clarification of the molecular basis of the inflammatory-related factors needs more consideration. The aim was to evaluate the gene expression of two fundamental molecules contributing to the induction of inflammatory like CCR2 and DPP9 in cells from peripheral blood samples from patients with various patterns of COVID-19.

Methods: Peripheral blood samples were collected from 470 patients (235 male and 235 female) with RT-qPCR-confirmed COVID-19 test exhibiting moderate, severe, and critical symptoms based on WHO criteria. 100 healthy subjects (50 male and 50 female) were also enrolled in the study as a control group. The gene expression of DPP-9 and CCR-2 was assessed in the blood samples using real-time PCR method.

Results: The COVID-19 patients in severe stage expressed higher levels of CCR2 and DPP9 compared with healthy controls. In male and female patients, the levels of CCR2 and DDP9 expression significantly differed between moderate, severe, and critical patterns (p < 0.0001) as well as between each COVID-19 form and control group (p < 0.0001). The male patients with severe COVID-19 expressed greater levels of CCR2 and DPP-9 than female with same disease form. The female patients with moderate and critical COVID-19 expressed greater levels of CCR2 and DPP-9 than male patients with same disease stage.

Conclusion: We demonstrated that the expression of DPP-9 and CCR-2 was substantially increased in COVID-19 patients with different forms of disease. Considerable differences were also demonstrated between male and female with different patterns of disease. Therefore, we suggest to consider the gender of patients and disease severity for management of COVID-19.

Keywords: CCR2; COVID-19; DPP9; Disease severity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • COVID-19*
  • Dipeptidyl-Peptidases and Tripeptidyl-Peptidases* / genetics
  • Dipeptidyl-Peptidases and Tripeptidyl-Peptidases* / metabolism
  • Female
  • Humans
  • Inflammation
  • Male
  • Receptors, CCR2* / genetics
  • Receptors, CCR2* / metabolism
  • Receptors, Chemokine
  • SARS-CoV-2
  • Severity of Illness Index


  • CCR2 protein, human
  • Receptors, CCR2
  • Receptors, Chemokine
  • DPP9 protein, human
  • Dipeptidyl-Peptidases and Tripeptidyl-Peptidases