ABSTRACT
Background: A lot of recent researches have focused on the duration of the nature immunity elicited by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. An improved understanding of the immunity offered by the antibodies developed against SARS-CoV-2 in recovered patients is critical for the development of diagnostic tests and vaccines. Methods: We enrolled 114 donors, which providing blood samples after discharge for half a year and one year. Neutralizing antibodies (NAbs) were tested using a micro-neutralization assay. Results: In two tests, 82 of 114 recovered patients completed the first test half a year after discharge and NAbs remained detectable in the vast majority of patients (75/82, 91.46%). In the comparison of the two intervals, 50% (27/54) of individuals had increased NAbs titers. when 31.48% (17/54) of patients remained unchanged. Conclusion: Our results suggest that immune ability is acquired in most individuals infected with SARS-CoV-2 and is sustained in a majority of patients for up to a year after recovery.
Subject(s)
COVID-19 , Coronavirus InfectionsABSTRACT
The SARS-CoV-2 Nucleoprotein (NCAP) functions in RNA packaging during viral replication and assembly. Computational analysis of its amino acid sequence reveals a central low-complexity domain (LCD) having sequence features akin to LCDs in other proteins known to function in liquid-liquid phase separation. Here we show that in the presence of viral RNA, NCAP, and also its LCD segment alone, form amyloid-like fibrils when undergoing liquid-liquid phase separation. Within the LCD we identified three 6-residue segments that drive amyloid fibril formation. We determined atomic structures for fibrils formed by each of the three identified segments. These structures informed our design of peptide inhibitors of NCAP fibril formation and liquid-liquid phase separation, suggesting a therapeutic route for Covid-19.