Cross-Neutralizing Breadth and Longevity Against SARS-CoV-2 Variants After Infections

Abstract

BackgroundSevere Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is the virus responsible for the Coronavirus Disease 2019 (COVID-19) pandemic. The emergence of variants of concern (VOCs) has become one of the most pressing issues in public health. To control VOCs, it is important to know which COVID-19 convalescent sera have cross-neutralizing activity against VOCs and how long the sera maintain this protective activity.MethodsSera of patients infected with SARS-CoV-2 from March 2020 to January 2021 and admitted to Hyogo Prefectural Kakogawa Medical Center were selected. Blood was drawn from patients at 1-3, 3-6, and 6-8 months post onset. Then, a virus neutralization assay against SARS-CoV-2 variants (D614G mutation as conventional strain; B.1.1.7, P.1, and B.1.351 as VOCs) was performed using authentic viruses.ResultsWe assessed 97 sera from 42 patients. Sera from 28 patients showed neutralizing activity that was sustained for 3-8 months post onset. The neutralizing antibody titer against D614G significantly decreased in sera of 6-8 months post onset compared to those of 1-3 months post onset. However, the neutralizing antibody titers against the three VOCs were not significantly different among 1-3, 3-6, and 6-8 months post onset.DiscussionOur results indicate that neutralizing antibodies that recognize the common epitope for several variants may be maintained for a long time, while neutralizing antibodies having specific epitopes for a variant, produced in large quantities immediately after infection, may decrease quite rapidly.

Novel monoclonal antibodies showing broad neutralizing activity for SARS-CoV-2 variants including Omicrons BA.5 and BA.2.75

“…The copyright holder for this preprint this version posted September 2, 2022. ; https://doi.org/10.1101/2022.09.02.506305 doi: bioRxiv preprint 9 neutralizing antibodies are sustained for >6 months, although neutralizing antibodies specific for SARS-CoV-2 (D614G) decline (Kurahashi et al, 2022a;Kurahashi et al, 2022b). It is also noteworthy that the booster dose (three-dose) vaccination using the mRNA vaccine based on wildtype SARS-CoV-2 can induce neutralizing antibodies against Omicron BA.1 and BA.2 (Furukawa et al, 2022;Tjan et al, 2022).…”

Large-scale serosurveillance of COVID-19 in Japan: Acquisition of neutralizing antibodies for Delta but not for Omicron and requirement of booster vaccination to overcome the Omicron’s outbreak

“…The details of the COVID-19 sera was provided in S2 Table . Note that five of the sera have been analyzed for their neutralizing antibody titers and reported in our previous study [ 19 ], although the anti-S ELISA was performed for the sera for the first time in this study. We set a cut-off value of 0.3 for the 1:40 dilution to define anti-S positivity considering the values for native sera; average 0.131 and standard deviation 0.020.…”

COVID-19 and the Immune Response: A Multi-Phasic Approach to the Treatment of COVID-19

“…Antibody responses to COVID-19 are essential for viral clearance. Antibody maturation increases the body’s ability to defend against SARS-CoV-2 infections [ 40 , 41 , 42 ]. When tested several months after infection, serum was discovered to have low antibody levels specific for single variants of SARS-CoV-2, but high levels of antibodies capable of recognizing the common epitope of several variants [ 40 ].…”

“…Antibody maturation increases the body’s ability to defend against SARS-CoV-2 infections [ 40 , 41 , 42 ]. When tested several months after infection, serum was discovered to have low antibody levels specific for single variants of SARS-CoV-2, but high levels of antibodies capable of recognizing the common epitope of several variants [ 40 ]. Additionally, even more antibody variance was prompted by repeated exposure to slightly different variants of the coronavirus [ 40 ].…”

“…Immune response between vaccines and natural infection differs in two main ways [ 40 , 41 , 42 ]. First, the immune response to a natural infection tends to be broader, as the infection itself may consist of several slightly different variants.…”