Two doses of SARS-CoV-2 vaccination induce robust immune responses to emerging SARS-CoV-2 variants of concern
Bibliographic record
Abstract
Abstract Both natural infection with SARS-CoV-2 and immunization with vaccines induce protective immunity. However, the extent to which such immune responses protect against emerging variants is of increasing importance. Such variants of concern (VOC) include isolates of lineage B.1.1.7, first identified in the UK, and B.1.351, first identified in South Africa. Our data confirm that VOC, particularly those with substitutions at residues 484 and 417, escape neutralization by antibodies directed to the ACE2-binding Class 1 and the adjacent Class 2 epitopes but are susceptible to neutralization by the generally less potent antibodies directed to Class 3 and 4 epitopes on the flanks of the receptor-binding domain. To address the potential threat posed by VOC, we sampled a SARS-CoV-2 uninfected UK cohort recently vaccinated with BNT162b2 (Pfizer-BioNTech, two doses delivered 18-28 days apart), alongside a cohort sampled in the early convalescent stages after natural infection in the first wave of the pandemic in Spring 2020. We tested antibody and T cell responses against a reference isolate of the original circulating lineage, B, and the impact of sequence variation in the B.1.1.7 and B.1.351 VOC. Neutralization of the VOC compared to B isolate was reduced, and this was most evident for the B.1.351 isolate. This reduction in antibody neutralization was less marked in post-boost vaccine-induced responses compared to naturally induced immune responses and could be largely explained by the potency of the homotypic antibody response. After a single vaccination, which induced only modestly neutralizing homotypic antibody titres, neutralization against the VOC was completely abrogated in the majority of vaccinees. Importantly, high magnitude T cell responses were generated after two vaccine doses, with the majority of the T cell response directed against epitopes that are conserved between the prototype isolate B and the VOC. These data indicate that VOC may evade protective neutralizing responses induced by prior infection, and to a lesser extent by immunization, particularly after a single vaccine dose, but the impact of the VOC on T cell responses appears less marked. The results emphasize the need to generate high potency immune responses through vaccination in order to provide protection against these and other emergent variants.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".