All statistical analyses were done using R (version 4

All statistical analyses were done using R (version 4.0.1). Results Study selection and data extraction We identified a total of 5, 182 studies after systematically searching multiple data sources with 2,307 coming from peer-reviewed databases, and 2,875 from preprint severs (Figure 1). reduction for RNA platform, and 1.6-fold (95% CI: 1.2C2.1) reduction for protein subunit platform. The neutralizing antibodies induced by administration of inactivated vaccines and mRNA vaccines against lineage P. 1 were also remarkably reduced by an average of 5.9-fold (95% CI: 3.7C9.3) and 1.5-fold (95% CI: 1.2C1.9). Interpretation: Our findings indicate that the antibody response established by natural infection or vaccination might be able to effectively neutralize B.1.1.7, but neutralizing titers against B.1.351 and P.1 suffered large reductions. Standardized protocols for neutralization assays, as well as updating immune-based prevention and treatment, are needed. Funding: Chinese National Science Fund for Distinguished Young Scholars Keywords: SARS-CoV-2 variants, neutralizing antibodies, natural infection, vaccination Introduction Since the first sequence of SARS-CoV-2 was published in January of 20201, over 1.1 million strains have been documented in Global Influenza Surveillance and Response System (GISAID)2, with recent reports of several newly emerged lineages, which has raised significant concerns globally. Of particular concern has been the emergence of lineage B.1.1.7 (UK variant, also ARP 100 known as 501Y.V1), lineage B.1.351 (South Africa variants, 501Y.V2), and lineage P.1 (Brazil variant, 501Y.V3), harboring several significant mutations in spike glycoproteins, which are key domains of virus-neutralizing antibodies3. These mutants rapidly became the dominant circulating virus strains in the regions where they were first isolated, and especially for B.1.1.7 and B.1.351, spread globally. Several vital mutations in the receptor-binding domain (RBD), such as N501Y in B.1.1.7 and E484K in B.1.351 and P.1, are associated with increased infectivity and decreased neutralizing potency, with potential to evade humoral immunity from prior infections or vaccinations4C8. Another variant of lineage B.1.427/B.1.429, which first emerged in California, was categorized as a Variant of Concern (VOC) in March 2021 according to classification developed by SARS-CoV-2 Interagency Group (SIG) in United States, containing a single L452R mutation in RBD in spike, whose ability of reduced sensitivity to neutralization has yet to be determined9. There is concern that SARS-CoV-2 variants can evade immune responses elicited by natural infections and vaccines that are based on the prototype strain (Wuhan-Hu-1). It has been shown that neutralization against variants by convalescent plasma is remarkably reduced by several mutations, including E484K shared by lineage B.1.351 and P.110. Serum collected from recipients of licensed vaccines have a decreased ability to neutralize emerging SARS-CoV-2 mutants to varying degrees, from 1.6-fold reduction for Chinas protein subunit vaccines to over 6-fold reduction for mRNA vaccines11C15. Additionally, consistent with immunogenicity results, a major loss of efficacy against B.1.351 was seen in NVX-CoV2373 and ChAdOx1 nCoV-19 vaccines16,17, though the efficacy was retained against B.1.1.7 for other vaccines18. However, existing studies of neutralizing potency against SARS-CoV-2 variants are based on limited numbers of samples and lack comparability between different laboratory methods. Furthermore, there are no studies providing whole picture of neutralizing antibodies induced by prior infections or vaccination against emerging variants. ARP 100 Here, we systematically summarize the evidence on neutralization ability against various SARS-CoV-2 variants among those previously-infected with strains from the original ARP 100 SARS-CoV-2 lineage and those who have been vaccinated. Methods Study Selection and Data Extraction We conducted a systematic search from six databases, including three peer-reviewed databases (PubMed, Embase and Web of Science) and three preprint servers (medRxiv, bioRxiv and Europe PMC), for studies published in English between Sep 1, 2020 and Apr 18, 2021 with predefined search terms (Table S1). We included studies that 1) reported neutralizing antibodies against SARS-CoV-2 variants by using serum or plasma collected from individuals with virologically or serologically-confirmed SARS-CoV-2 infections, Rabbit polyclonal to NF-kappaB p65.NFKB1 (MIM 164011) or NFKB2 (MIM 164012) is bound to REL (MIM 164910), RELA, or RELB (MIM 604758) to form the NFKB complex. and vaccine recipients; and 2) reported or displayed individual antibody titers with summary tables or high-resolution images. Studies that 1) investigated the efficacy of monoclonal and therapeutic antibodies against variants; 2) reported seroprevalence of variants; 3) only detected non-neutralizing antibodies; or 4) reported specific mutation sites from a view of biological mechanism, were excluded. We also excluded abstracts of congress meetings or conference proceedings, study protocols, media news,.