Was the WIV [Wuhan Institute of Virology] doing experiments that might release PPPs [Potential Pandemic Pathogens]?
Since 2004, shortly after the original SARS outbreak, researchers from the WIV have been collecting bat coronaviruses in an intensive search for SARS-like pathogens (Li et al., 2005). Since the original collecting trip, many more have been conducted (Ge et al., 2013; Ge et al., 2016; Hu et al., 2017; Zhou et al., 2018).
Petrovsky does not mention it but Zheng-Li Shi’s group at the WIV has already performed experiments very similar to those he describes, using those collected viruses. In 2013 the Shi lab reported isolating an infectious clone of a bat coronavirus that they called WIV-1 (Ge et al., 2013). WIV-1 was obtained by introducing a bat coronavirus into monkey cells, passaging it, and then testing its infectivity in human (HeLa) cell lines engineered to express the human ACE2 receptor (Ge et al., 2013).
In 2014, just before the US GOF research ban went into effect, Zheng-Li Shi of WIV co-authored a paper with the lab of Ralph Baric in North Carolina that performed GOF research on bat coronaviruses (Menachery et al., 2015).
In this particular set of experiments the researchers combined “the spike of bat coronavirus SHC014 in a mouse-adapted SARS-CoV backbone” into a single engineered live virus. The spike was supplied by the Shi lab. They put this bat/human/mouse virus into cultured human airway cells and also into live mice. The researchers observed “notable pathogenesis” in the infected mice (Menachery et al. 2015). The mouse-adapted part of this virus comes from a 2007 experiment in which the Baric lab created a virus called rMA15 through passaging (Roberts et al., 2007). This rMA15 was “highly virulent and lethal” to the mice. According to this paper, mice succumbed to “overwhelming viral infection”.
In 2017, again with the intent of identifying bat viruses with ACE2 binding capabilities, the Shi lab at WIV reported successfully infecting human (HeLa) cell lines engineered to express the human ACE2 receptor with four different bat coronaviruses. Two of these were lab-made recombinant (chimaeric) bat viruses. Both the wild and the recombinant viruses were briefly passaged in monkey cells (Hu et al., 2017).
Together, what these papers show is that: 1) The Shi lab collected numerous bat samples with an emphasis on collecting SARS-like coronavirus strains, 2) they cultured live viruses and conducted passaging experiments on them, 3) members of Zheng-Li Shi’s laboratory participated in GOF experiments carried out in North Carolina on bat coronaviruses, 4) the Shi laboratory produced recombinant bat coronaviruses and placed these in human cells and monkey cells. All these experiments were conducted in cells containing human or monkey ACE2 receptors.
The overarching purpose of such work was to see whether an enhanced pathogen could emerge from the wild by creating one in the lab. (For a very informative technical summary of WIV research into bat coronaviruses and that of their collaborators we recommend this post, written by biotech entrepreneur Yuri Deigin).
It also seems that the Shi lab at WIV intended to do more of such research. In 2013 and again in 2017 Zheng-Li Shi (with the assistance of a non-profit called the EcoHealth Alliance) obtained a grant from the US National Institutes of Health (NIH). The most recent such grant proposed that:
“host range (i.e. emergence potential) will be tested experimentally using reverse genetics, pseudovirus and receptor binding assays, and virus infection experiments across a range of cell cultures from different species and humanized mice” (NIH project #5R01Al110964-04).
It is hard to overemphasize that the central logic of this grant was to test the pandemic potential of SARS-related bat coronaviruses by making ones with pandemic potential, either through genetic engineering or passaging, or both.
Apart from descriptions in their publications we do not yet know exactly which viruses the WIV was experimenting with but it is certainly intriguing that numerous publications since Sars-CoV-2 first appeared have puzzled over the fact that the SARS-CoV-2 spike protein binds with exceptionally high affinity to the human ACE2 receptor “at least ten times more tightly” than the original SARS (Zhou et al., 2020; Wrapp et al., 2020; Wan et al., 2020; Walls et al., 2020; Letko et al., 2020).
This affinity is all the more remarkable because of the relative lack of fit in modelling studies of the SARS-CoV-2 spike to other species, including the postulated intermediates like snakes, civets and pangolins (Piplani et al., 2020). In this preprint these modellers concluded “This indicates that SARS-CoV-2 is a highly adapted human pathogen”.
Given the research and collection history of the Shi lab at WIV it is therefore entirely plausible that a bat SARS-like cornavirus ancestor of Sars-CoV-2 was trained up on the human ACE2 receptor by passaging it in cells expressing that receptor.
[On June 4 an excellent article in the Bulletin of the Atomic Scientists went further. Pointing out what we had overlooked, that the Shi lab also amplified spike proteins of collected coronaviruses, which would make them available for GOF experimentation (Ge et al., 2016).]