The Correlation of Platelet-Monocyte Aggregate Formation and IFITM3 Gene Expression with COVID-19 Severity.

Background: Platelet-leukocyte aggregates have been implicated in various infectious and inflammatory diseases. The Interferon-induced transmembrane protein 3 (IFITM3) protein plays a role in eliminating viral infections, but its role in the severity of COVID-19 is not well understood. Objectives: We aimed to investigate the correlation between IFITM3 mRNA expression and platelet-monocyte complex levels with the severity of COVID-19, as well as various inflammatory and coagulation markers. Methods: We conducted a cross-sectional study on 54 COVID-19 patients, classified into severe and mild/moderate subgroups. Demographics and laboratory findings were extracted from patients' medical records. We measured IFITM3 mRNA expression in patients' buffy coats using q-RT-PCR and used flow cytometry with CD61 and CD14 markers to measure platelet-monocyte aggregates. Results: No significant difference was found in IFITM3 mRNA expression levels or platelet-monocyte complexes between severe and mild/moderate groups (P = 0.067 and P = 0.056). Lymphocyte counts were significantly higher in the mild/moderate subgroup (21.7 ± 8.9 vs 16.3 ± 10.9, P = 0.02), while neutrophil counts were significantly higher in severe patients (78.3 ± 12.2 vs 72.3 ± 9.9, P = 0.01). Additionally, levels of CRP and LDH were significantly higher in severe COVID-19 patients (P = 0.01 and P = 0.001, respectively). A strong positive correlation was observed between the hospitalization period and CRP, CRP with neutrophils and LDH, as well as between O2 saturation and lymphocytes (P < 0.001, P = 0.0003, P = 0.002, and P = 0.005, respectively). Conclusions: Our findings suggest that IFITM3 gene expression and platelet-monocyte aggregate levels do not correlate with disease outcomes in COVID-19. However, further investigations with larger sample sizes are needed to better understand the mechanisms involved. Monitoring inflammatory and coagulation markers remains important for managing COVID-19 patients. [ABSTRACT FROM AUTHOR]