Association of Neutrophil Gene Expression with 28-Day Ventilator Weaning in COVID-19 ARDS Patients (part 2)

Rationale COVID-19 can cause ARDS, a life-threatening condition that requires long-term ventilation. Neutrophil activation is a key mediator of lung injury in ARDS. However, the relationship between peripheral neutrophil RNA expression at the time of severe illness and 28-day ventilator weaning has not yet been clarified. Objectives To clarify the relationship with 28-day ventilator weaning and whole blood RNA sequencing analysis in COVID-19 patients. Moreover, single-cell RNA-seq was performed on neutrophils to analyze changes in gene expression levels for each fraction. Methods Bulk sequencing was performed using whole blood from 28 COVID-19 ARDS patients (9 in the non-ventilator weaning group and 19 in the ventilator weaning group) and 16 healthy controls. Next, single-cell RNA-seq was performed on neutrophils isolated from peripheral blood of 5 COVID-19 ARDS patients (3 in the non-ventilator weaning group and 2 in the ventilator weaning group) and 6 healthy individuals. Measurements and Main Results Although there was no clear difference between the non-ventilator weaning group and the ventilator weaning group in bulk RNA-seq using whole blood, the result of single-cell RNA-seq revealed clear differences between the non-ventilator weaning group, the ventilator weaning group, and healthy individuals. Conclusions Our study suggests that gene expression in neutrophils at the time of severe illness in COVID-19 ARDS patients may be associated with 28-day ventilator weaning. Overall design: Granulocytes were isolated from whole blood using gradient centrifugation and RBC lysis buffer