Table 1.
Tables showing the immuno-escape index (I-index), evaluating of the level of resistance of a SARS-CoV-2 variant to neutralising antibodies (nAb) directed against the RBD and the NTD of the spike protein. I-index is considered significant if >2. (wt = Original/B.1.1, mut = other).
| Virus Strains | ∆G RBD (LyCoV-555) kJ.mol−1 |
∆G NTD (4A8) kJ.mol−1 |
I-index (Immuno-Escape) 1 |
MNT ≥ 1/5 (nb/55) |
|---|---|---|---|---|
| Original/B.1.1 | −244 | −225 | 1.0 | 36/55 (65%) |
| Marseille-4/B.1.160 | −245 | −225 | 1.0 | 35/55 (64%) |
| B.1.214.2 | −210 | −225 | 1.1 | 39/55 (71%) |
| Alpha | −195 | 241 | 1.2 | 38/55 (69%) |
| Beta | −75 | −118 | 2.6 | 21/55 (38%) |
| Gamma | −80 | −82 | 2.9 | 34/55 (62%) |
| Marseille-484K.V1 | −36 | −258 | 3.0 | 28/55 (51%) |
| Marseille-501/A.27 | −59 | −114 | 3.1 | 34/55 (62%) |
| Delta/B.1.617.2 | −68 | −88 | 3.1 | 25/49 (51%) |
| Delta/AY.37 | −68 | −76 | 3.3 | 16/41 (39%) |
1 I-index = 1/2 (ΔGwt/ΔGmut (RBD-nAb) + ΔGwt/ΔGmut (NTD-nAb)). The formula was designed so that the reference virus retrieved from PDB files 7KMG and 7C2 L had an I-index = 1. Under these conditions, the variants of the present studies could be classified into two groups: those with an I-index close to 1 (Marseille-4/B.1.160, B.1.214.2, and Alpha variants) that are predicted to be efficiently neutralised by natural and/or vaccinal nAbs and those with an I-index >2 (Beta, Marseille-484K.V1/R.1, Marseille-501/A.27, Gamma, Delta/B.1.617.2, and Delta/AY.37) that are likely to resist seroneutralisation.