The authors speak to only testing for antibodies to the spike protein, then they say people who actually got COVID-19 have a lot of antibodies to yhe rest of the virus length.
So, your point is?
The point is the title is a lie.
Here's a neat video from LabCorp that explains the various components of the Covid-19 (SARS-CoV-2) corona virus.
First, this is a very simplified but very good explanation of the actual SARS-CoV-2 virus particle, and its main components.
1: The nucleocapsid (RNA and N-protein) which is the heart of the virus, that actually overtakes the infected human cell and replicates itself continuously and advances the infection.
2: The shell of the virus, that supports the E-Protein, M-Protein, and others (unnamed, but irrelevant to this presentation)
3: The all important Spike Glycoprotein (S), The spike protein is the actual mechanism the virus uses to attach itself to the ACE2 receptor of a human cell and capture that cell to advance the infection.
Second, the video explains three different "Qualitative" antibody assays, specifically:
1: SARS-CoV-2 nucleocapsid antibody assay (164068) which detects high affinity antibodies to the nucleocapsid (RNA and N-protein) of the actual virus.
2: SARS-CoV-2 antibody IgG Spike assay (164055) which detects Mature IgG antibodies to the Spike protein of the actual virus.
3: SARS-CoV-2 antibody IgM Spike assay (164034) which detects Mature IgM antibodies to the Spike protein of the actual virus.
Third, the video presents the new SARS-CoV-2 Semi-Quantitative Total Antibody, Spike assay, (164090):
The description of this (164090) is a little sketchy in this video, but from other documentation it is clear that it is specifically focused on the modified Spike protein generated by the mRNA vaccines, and its best purpose is to measure the level of antibodies to the vaccine generated Spike protein
Fourth, note in that video that the focus is primarily on the 164090 Spike protein (vaccine generated) assay, and does not focus on "Qualitative" assays, the only assays for natural infection recovery generated antibodies.
There are actually some very important points made in the video discussion of the new "Quantitative" assay (164090).
1: This assay focuses on the Spike (S) protein generated by the mRNA vaccine, and NOT on the nucleocapsid (RNA and N-protein) which is the heart of the virus.
2: The meaning of the number produced by the assay is not yet fully characterized beyond indicating whether the person has antibodies and CANNOT at this time interpreted to indicate immunity.
3: So why was it launched? It is being used in many studies, and will be correlated with a number of different nutralization assays and parameters, making it more flexible in the long term for a post vaccination world.
4: It's available now to all LabCorp customers.
My personal note: I interpreted LabCorp's advertising of this ($10) test as showing whether you had been previously infected and recoverd from Covid-19, and got the test. It clearly does NOT show whether you had been previously infected and recoverd from Covid-19, and that is stated clearly in my test report. I then tried to order the correct qualitative test (164068) and they refused, stating 164068 could ONLY be orderd by doctors.
So what does that mean, and why is it important?
All previous expectations of the mRNA vaccines aside, this video clearly indicates that current measures of antibodies to this vaccine generated spike protein CANNOT be interpreted to provide immunity against Covid-19 infection.
And you just got that straight from the horse's mouth (LabCorp)