ABSTRACT
BACKGROUND: Lots of research has been conducted to fight COVID-19 since the outbreak of the pandemic in 2020. The role of 'cytokine storm' in the pathogenesis of COVID-19 pneumonia is well known. Relationship between interleukins and depression is still subject matter of the research, but a correlation between interleukin-6 and depressive disorders is proven by now. The aim of this study is to verify differences among interleukin-6 blood levels of inpatients treated with SSRI and/or SNRI before and during hospitalization and of inpatients not treated with these drugs. METHODS: This is an observational study performed during the first wave of SARS Cov-2 pandemic in Italy for three months. The hospitalized patients of Internal Medicine wards and Infectious and Tropical Diseases ward of Azienda Ospedaliero-Universitaria Careggi of Florence for COVID-19 pneumonia have been divided into two subgroups (treated / not treated with antidepressants). Patients admitted to Intensive Care Unit previously have been excluded. Each patient has been evaluated concerning demographic, clinical and therapeutic features. The first dosage of interleukin-6 detected during hospitalization has been noticed. RESULTS: 8,5% (n=34 patients) of the entire sample (n=402) had been treated with an antidepressant of the two considered categories before admission until discharge from hospital. Significant lower levels of interleukin-6 of recovered patients of the treated subgroup have been highlighted as compared to recovered patients of not-treated subgroup (12,1 vs 25,4 p<0,001). These results have been pointed out in spite of higher mean age and more serious comorbidities of the treated subgroup. Nevertheless the incidence of severe Acute Respiratory Distress Syndrome is significantly lower in the subgroup of patients with antidepressant treatment (20,6% vs 43,2% p<0,02) as well as endotracheal intubation employment (0,0% vs 11,7% p<0,04). The rate of deceased patients of treated-subgroup is not significant lower than the rate of not-treated subgroup (23,5% vs 26,4% p=0,13). CONCLUSIONS: During COVID-19 pneumonia, the production of interleukin-6 seems to be modulated in presence of antidepressant therapy. Further proofs and broader surveys are necessary.
ABSTRACT
The characterization of cell-mediated and humoral adaptive immune responses to SARS-CoV-2 is fundamental to understand COVID-19 progression and the development of immunological memory to the virus. In this study, we detected T-cells reactive to SARS-CoV-2 proteins M, S, and N, as well as serum virus-specific IgM, IgA, IgG, in nearly all SARS-CoV-2 infected individuals, but not in healthy donors. Virus-reactive T cells exhibited signs of in vivo activation, as suggested by the surface expression of immune-checkpoint molecules PD1 and TIGIT. Of note, we detected antigen-specific adaptive immune response both in asymptomatic and symptomatic SARS-CoV-2 infected subjects. More importantly, symptomatic patients displayed a significantly higher magnitude of both cell-mediated and humoral adaptive immune response to the virus, as compared to asymptomatic individuals. These findings suggest that an uncontrolled adaptive immune response contribute to the development of the life-threatening inflammatory phase of the disease. Finally, this study might open the way to develop effective vaccination strategies.