CDC Finds MAJOR Cross-Reactivity B/T Sars &Sars-Cov-2
I was looking for research studies this evening regarding Virial isolation of sars-cov-2 for standardized reference comparison when running PCR when I came about this published CDC journal.
Page created: May 18, 2020, Published June 2020
A patient was identified with confirmed COVID-19 in Washington State on January 22, 2020. They isolated the virus. (not sure what strain that was at the time) and found Major Cross Reactivity with the Nucleocapsid Protein, and Spike Protein between Sars & Sars-cov-2.
Below are Excerpts:
we next evaluated the
cross-reactivity of SARS-CoV antibodies against the
SARS-CoV-2. Cell lysates from infected cell lines were
probed for protein analysis; we found that polyclonal
serum against the SARS-CoV spike protein and nucleocapsid proteins recognize SARS-CoV-2 (Figure 3,
panels B, C). The nucleocapsid protein, which is highly conserved across the group 2B family, retains >90%
amino acid identity between SARS-CoV and SARSCoV-2. Consistent with the replication results (Figure 3, panel A), SARS-CoV-2 showed robust nucleocapsid protein in both Vero cell types, less protein in
HUH7.0 and 293T cells, and minimal protein in A549
and EFK3B cells (Figure 3, panel B). The SARS-CoV
spike protein antibody also recognized SARS-CoV-2
spike protein, indicating cross-reactivity (Figure 3,
panel C). Consistent with SARS CoV, several cleaved
and uncleaved forms of the SARS-CoV-2 spike protein were observed.
The Next Sentence surprised me……..
♥♥♥The cleavage pattern of the SARS
spike positive control from Calu3 cells, a respiratory
cell line, varies slightly and could indicate differences
between proteolytic cleavage of the spike proteins between the 2 viruses because of a predicted insertion
of a furin cleavage site in SARS-CoV-2 (16) !!!
Is this the smoking Gun? Did the authors just conclude that SARS-COV-2 did not naturally originate!?
Overall, the protein expression
data from SARS-CoV nucleocapsid and spike protein antibodies recapitulate replication findings and
indicate that SARS-CoV reagents can be used to characterize SARS-CoV-2 infection.
Citation 16: The spike glycoprotein of the new coronavirus 2019-nCoV contains a furin-like cleavage site absent in CoV of the same clade.
^^ View Open Manuscript
SARS-COV cross reactivity with SARS-COV-2