Delta variant becoming Delta 4+, and the vaccines then enhance infections

This is an important point worth analyzing. If the sentence in question is improperly worded, then that should be thoroughly explained with other citations from the study.

But it does not make sense that infectivity would be enhanced because of lost neurtralizing activity.

It might make sense that infectivity would be allowed to increase on its own as in unvaccinated cases, in which case nothing more need be said.

But that is not at all the same as enhancing infectivity, which is what was actually stated as happening in addition to losing neutralizing activity.

The “and” refers to “some BNT162b2-immune sera” associating both actions with it, that is, with losing neutralizing activity and with enhancing the infectivity.

Thus,

“…some BNT162b2-immune sera lost neutralizing activity…”

“and” that same

“…[some BNT162b2-immune sera] enhanced the infectivity….”

 

From the study :

Moreover, we and others have recently demonstrated that antibodies against a specific
site on the NTD can enhance the infectivity of SARS-CoV-2 by inducing the open form of the
RBD (Li et al., 2021; Liu et al., 2021b).​

One section is headed:

Enhanced infectivity of the Delta 4+ pseudovirus by some BNT162b2-immune sera.​

https://www.biorxiv.org/content/10.1101/2021.08.22.457114v1.full.pdf

 

Two excerpts from the study:

Surprisingly, most BNT162b2-immune sera enhanced infectivity of the Delta 4+ pseudovirus in a dose-dependent manner at relatively low concentrations of BNT162b2-immune sera, but showed weak neutralization only at the highest concentration of the sera (Figure 6D and 6E). Especially, PFZ7 greatly enhanced the infectivity at relatively low serum concentration. Some sera, such as PFZ13 and PFZ14, did not show neutralizing activity even at the highest concentration of the sera. The neutralizing titers of PFZ13 and PFZ14 against wild-type or Delta variant were apparently lower than others (Figure 2A). On the other hand, PFZ15 effectively neutralized the Delta 4+ pseudovirus, but the neutralizing titers of PFZ15 against the wild type and Delta variant were not particularly high compared to the others. Because most neutralizing antibodies against either NTD or RBD do not work for the Delta 4+ pseudovirus, while most enhancing antibodies remain functional for the Delta 4+ pseudovirus, the increased infectivity in the presence of BNT162b2-immune sera appears to be mediated by anti-NTD enhancing antibodies.


Therefore, additional immunization of the spike protein derived from SARS-CoV-2 variants may boost enhancing antibodies more than the neutralizing antibodies in individuals who were previously infected with wild-type SARS-CoV-2 or immunized with vaccines composed of wild-type spike protein. Immunization using the RBD alone, which will not induce anti-NTD enhancing antibodies, could be a strategy for a vaccination. However, anti-NTD neutralizing antibodies that protect against SARS-CoV-2 infection similar to anti-RBD-neutralizing antibodies are not induced by immunization by RBD alone (Chi et al., 2020; Li et al., 2021 ; Liu et al., 2020; Suryadevara et al., 2021; Voss et al., 2021). Whole spike protein containing RBD mutations observed in major variants but lacking the enhancing antibody epitopes may need to be considered as a booster vaccine.​

 

Are you being an evil fool again and intentionally posting misinformation?

 

Yes, that's clearly a discussion of neutralizing versus non-neutralizing antibodies, which is of prime concern when discussing antibody-dependent enhancement. Jon was twisting the meaning of the words, again.

 

Read...the...article.

"Enhancing antibodies increase the infectivity of SARS-CoV-2 by inducing the open form of the RBD (Liu et al., 2021b)."

"These data suggested that the Delta variant completely escaped from anti-NTD neutralizing antibodies while maintaining functional enhancing antibody epitopes."