ABSTRACT
Purpose Long-term immunity after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in immunosuppressed patients is not well characterized. We aimed to explore the long-term natural immunity against SARS-CoV-2 in liver transplant (LT) recipients compared to the non-transplanted population (control group) Methods Fifteen LT recipients and 15 controls matched according to variables associated with disease severity were included at 12 months following the coronavirus disease 2019 (COVID-19) onset. Peripheral blood mononuclear cells were stimulated with peptide pools covering spike (S), nucleocapside (N), and membrane (M) proteins. Reactive CD4+ and CD8+ T cells were identified using flow cytometry, and cytokine production was evaluated in the culture supernatants using cytometric bead array. Serum anti-N and anti-S IgG antibodies were detected with chemiluminescence. Results The percentage of patients with a positive response in both CD4+ and CD8+ T cells against each viral protein and IL2, IL10, TNF-α, and IFN-γ levels was similar between LT recipients and controls. IFN-γ levels were positively correlated with the percentage of reactive CD4+ (p=0.022) and CD8+ (p=0.043) T cells to a mixture of M + N + S peptide pools. The prevalence and levels of anti-N and anti-S IgG antibodies were slightly lower in the LT recipients, but the difference was not statistically significant. Conclusion LT recipients exhibited a similar T cell response compared to non-transplanted individuals one year after COVID-19 diagnosis.
ABSTRACT
BACKGROUND: COVID-19 is a potentially severe disease caused by the recently described SARS-CoV-2. Whether liver fibrosis might be a relevant player in the natural history of COVID-19 is currently unknown. We aimed to evaluate the association between FIB-4 and the risk of progression to critical illness in middle-aged patients with COVID-19. METHODS: In this multicenter, retrospective study with prospective follow-up of 160 patients aged 35-65 years with COVID-19, FIB-4, clinical, and biochemical variables were collected at baseline. FIB-4 ≥2.67 defined patients with risk for advanced liver fibrosis. RESULTS: Risk for advanced fibrosis was estimated in 28.1% of patients. Patients with FIB-4 ≥2.67 more frequently required mechanical ventilation (37.8% vs 18.3%; P = .009). In multivariate analysis, FIB-4 ≥2.67 (odds ratio [OR], 3.41; 95% confidence interval [CI], 1.30-8.92), cardiovascular risk factors (OR, 5.05; 95% CI, 1.90-13.39), previous respiratory diseases (OR, 4.54; 95% CI, 1.36-15.10), and C-reactive protein (OR, 1.01; 95% CI, 1.01-1.02) increased significantly the risk of ICU admission. Bootstrap confirmed FIB-4 as an independent risk factor. CONCLUSIONS: In middle-aged patients with COVID-19, FIB-4 may have a prognostic role. The link between liver fibrosis and the natural history of COVID-19 should be evaluated in future studies.