Background information
SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) was first detected in December 2019 in Wuhan, China. Since that time the virus kept mutating, leading to new virus variants. The B.1.1.7 lineage, also known as Alpha variant, VUI202012/01 or VOC202012/01, is a SARS-CoV-2 variant that was first discovered in Kent, UK in September 2020. The mutations of this variant affect also immune relevant parts of structural SARS-CoV-2 proteins and the respective sequences are available in GISAID, a genome data base, e.g. reference sequence EPI_ISL_756151. The B.1.1.7 lineage (Alpha variant) has been found to be more infectious than former variants and has become quickly the dominant strain in the UK.
In total there are 10 mutations in the surface or spike glycoprotein (“S”) of the B.1.1.7 lineage (Alpha variant) compared to the Wuhan variant (reference genome GenBank MN908947.3): deletion 69, deletion 70, deletion 144, N501Y, A570D, D614G, P681H, T716I, S982A, D1118H.
PepTivator
® SARS-CoV-2 Prot_S B.1.1.7 Mutation Pool covers selectively the mutated regions. It consists of 34 peptides of mainly 15 aa length. The PepTivator SARS-CoV-2 Prot_S B.1.1.7 Mutation Pool can be used to supplement PepTivators covering the sequence of the wild-type spike glycoprotein (“S”) in order to detect immune responses towards both variants, Wuhan (wildtype) variant and B.1.1.7 lineage (Alpha variant). PepTivator Peptide pools spanning the sequence of the spike glycoprotein (“S”) of the Wuhan (wild-type) variant are PepTivator SARS-CoV-2 Prot_S (predicted immunodominant sequence domains), SARS-CoV-2 Prot_S1 (N-terminal S1 domain) and SARS-CoV-2 Prot_S+ (part of the C-terminal S2 domain).
PepTivator SARS-CoV-2 Prot_S B.1.1.7 WT Reference Pool consists of the 34 homologous peptides of the Wuhan sequence and covers H69, V70, Y144, N501, A570, D614, P681, T716, S982, D1118 of the Wuhan variant (reference genome GenBank MN908947.3). PepTivator SARS-CoV-2 Prot_S B.1.1.7 WT Reference Pool serves as a control for the PepTivator SARS-CoV-2 Prot_S B.1.1.7 Mutation Pool. Comparison of the T cell immune response upon stimulation with mutation and reference pool can be used to analyze mutation-specific T cell responses.