Covid- ۱۹ patients neutrophil against Staphylococcus aureusand Pseudomonas aeruginosa

Background and Aim : COVID-۱۹ was first described in December ۲۰۱۹. It spreads through therespiratory tract with lymphopenia and cytokine storms and caused severe acute respiratorysyndrome coronavirus ۲ (SARS-CoV-۲). It mainly happened in severe disease and showed theexistence of immunological dysregulation in severe disease.Neutrophils have significant role inthe host defence against micro-organisms and are the important effector cells to combat and killingof pathogens by oxidative burst andphagocytosis. The peripheral blood of COVID-۱۹ patients haveincreased numbers of neutrophils which are important in controlling the bacterial infectionsobserved in COVID-۱۹. Since bacterial co-infection is observed in COVID-۱۹ patients, wehypothesized that neutrophils from these patients may have functional defects with respect tobacterial killing of Staphylococcus aureus and Pseudomonas aeruginosa. Thus, we aimed tocompare the ability of peripheral blood PMN obtained from healthy control subjects and COVID-۱۹ patients to evoke bacterial killing ex vivo over time.Methods : ۳۴ COVID-۱۹ patients and ۹ healthy control subjects were enrolled at the MasihDaneshvari Hospital. PMN cells were isolated from whole blood. The Methicillin ResistanceStaphylococcus Aureus (SA) and Pseudomonas Aeruginosa (PA) were used. Isolated PMN wereco-cultured with PA and SA, The plate was placed in the FLUOstar and GFP fluorescence wasmeasured and then stained with Annexin V-FITC and PI (Invitrogen™ ۸۸-۸۰۰۵-۷۲) (UK) basedon the manufacturer's instructions. the result data were calculated based on FL۱ and FL۲(FlowJo™ software).Results : PMN from COVID-۱۹ patients were significantly less efficient reducing the lag time ofGFP-SA (۲۲ ± ۰.۹ versus ۹.۲ ± ۰.۵ hours, P < .۰۱ and GFP-PA (۱۲.۴ ± ۰.۶ versus ۴.۵ ± ۰.۲۲ hours,P < .۰۱ than cells from healthy control subjects.Conclusion : This pilot study demonstrated a decreased bacterial killing capacity of neutrophilsisolated from the systemic circulation of COVID-۱۹ patients in comparison with control healthysubjects against both Gram-positive and Gram-negative bacteria.

کلیدواژه ها:

COVID-۱۹ ، Neutrophil ، Staphylococcus aureus ، Pseudomonas aeruginosa