High Serum Progranulin Levels in COVID-19 Patients: A Pilot Study.

In this study, we aimed to determine whether the progranulin level in serum predicts the course and severity of the disease in COVID-19 (+) patients and whether it can be used as a biomarker in these patients. Therefore, we sampled 61 people infected with COVID-19, and the cases were divided into the following groups: asymptomatic, noncomplicated, moderate, and severe. Concentrations of progranulin, TNF-α, IL-6 from in serum obtained from all participants were measured using commercially available ELISA kits, as well as WBC, PLT, NE, LY, ALT, AST, Hb, PCT, and CRP were examined with clinical analyzer. All measurements obtained for the patient samples were compared with those of 20 healthy individuals. The serum progranulin concentration was statistically higher in the COVID-19 (+) patient group than in the control group of healthy individuals [112.6 ± 54.8, 0.0 (0.0-54.2 pg/ml, respectively p = 0.000)]. ROC analysis was performed to evaluate the progranulin potential as a biomarker for COVID-19 (+) patients. A larger AUC (0.931 ± 0.08) value and a more significant p-value for progranulin than for CRP (p = 0.000) was detected. As a result, we believe that progranulin reaches high levels in the COVID-19 disease and may be a determinant in diagnosis and prognosis, and may be a better biomarker than CRP.

Serum Protein Profiling Reveals a Specific Upregulation of the Immunomodulatory Protein Progranulin in Coronavirus Disease 2019.

BACKGROUND: Severe courses of coronavirus disease 2019 (COVID-19) are associated with elevated levels of interleukin 6 (IL-6). However, there is a growing body of evidence pointing to a broad and more complex disorder of proinflammatory and antiviral responses with disturbed interferon signaling in COVID-19. METHODS: In this prospective, single-center registry, we included severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-positive patients and patients with similar symptoms and severity of disease but negative for SARS-CoV-2 admitted to the emergency department and compared their serum protein expression profiles. RESULTS: IL-6 abundance was similar in SARS-CoV-2-positive patients (n = 24) compared with SARS-CoV-2-negative controls (n = 61). In contrast, we observed a specific upregulation of the immunomodulatory protein progranulin (GRN). High GRN abundance was associated with adverse outcomes and increased expression of IL-6 in COVID-19. CONCLUSIONS: The data from this registry reveal that GRN is specifically upregulated in SARS-CoV-2-positive patients while IL-6 may serve as marker for disease severity. The potential of GRN as a biomarker and a possible impact of increased GRN expression on interferon signaling, virus elimination, and virus-induced lung tissue damage in COVID-19 should be further explored.