The SARS-CoV-2 viruses are single-strands of large RNAs, encased in an envelope that has club-like projections/spikes on the outer surface.
The virions are spherical with a diameter of about 125nm. Within the envelope of the virion is the helical structure known as the nucleocapsid.
The virus has four main structural proteins:
- The Spikes (S) protein
- The membrane (M) protein
- The envelope (E) protein
- The nucleocapsid. (N) protein
- The Club-shaped spikes project from the surface of the virion. The spike projections give the virion, the solar corona appearance, hence the name coronavirus.
It is the spike proteins that help the virus to attach to cells, and subsequently, release the viral genome into the cytoplasm of the host cells, using the angiotensin-converting enzyme 2 (ACE2) as receptors.
It is the same spike proteins that have become the target for vaccine manufacturers. This is because, research indicates that the host adapts to coronavirus infections by generating both neutralizing antibodies, and killer T-cells that target the spike proteins.
Covid-19 antibodies block the corona spikes from attaching to host cells; the killer T-cells seek and destroy any coronavirus-infected cells
Pfizer-BioNTech COVID-19 Vaccines.
On December 11, 2020, the FDA authorized the use and distribution of Pfizer-BioNTech COVID-19 vaccine for prevention of COVID-19 in individuals 16 years of age, and older, in the USA.
This is a 2-dose vaccine administered intramuscularly (usually the shoulder deltoid muscle), 21 days apart.
The Pfizer-BioNTech covid-19 vaccine helps vaccinated persons to produce antibodies, and killer T-cells against the spike proteins on the surface of the cell-walls of the virus
Scientist have identified and isolated the genomic material that code for the Spike protein production. These strands of RNA, known as messenger RNA (mRNA) are easily degradable.
To protect the mRNA strands from degradation until they arrive at the cytoplasm of the host cells, the mRNAs, have been packaged inside very tiny fat droplets in the vaccine.
At the surface of the host cells, the fat droplets fuse with the cell membranes to release the mRNAs into the cytoplasm.
While inside the cytoplasm, the mRNAs signal the host cells to generate more spike proteins that can alert the immune system to produce neutralizing antibodies and killer T-cells against the spike proteins.
Having completed their task, the mRNAs are readily degraded.
So, the RNA vaccines stay in the cytoplasm only. RNA vaccines do not enter the nucleus of cells. They cannot modify host genes.
The RNA vaccines are very safe; the introduced mRNAs are readily degraded. Not only that, because the RNA vaccines use already existing protein synthetic pathways in the cells, the phases of vaccine trials were faster. Vaccine trials took less than a year to complete.
The trials the vaccines have shown that the RNA vaccines are safe, and with over 95% efficacy, not only in young persons, but also in the elderly.
Common side effect of the Pfizer-BioNTech COVID-19 Vaccine.
- Pain at the injection site
- Fever. Headache. Tiredness
- Muscle, and Joint pain
Very rarely, an individual could develop anaphylactic reaction to the vaccine. Those with history of anaphylaxis, need to be monitored for up to one hour, after receiving the vaccine. Epinephrine injections must be made available.
THE DNA COVID-19 VACCINES,
The DNA vaccines use chimp Adenovirus as vaccine vectors.
The adenovirus vectored vaccine technology has been in development for decades. The technique was fast-tracked following the covid-19 epidemic.
Scientist use chimp adenovirus to escape the human immune surveillance system.
Genetic engineers removed portions of the chimp adenovirus DNA to make it replication incompetent (it can’t make copies of itself), and immunogenic competent (capable of stimulating the host’s adaptive immunity).
They then replaced those portions of the DNA with the covid-19 virus genome that code for the Spike proteins.
After vaccination, the chimp adenovirus reaches the host cells, and releases the modified DNA into the cytoplasm. The modified DNA is taken up the nucleus of the cells.
The nucleus then reads the covid-19 codes and generates the specific messenger RNAs that tell the ribosomes to manufacture the Covid-19-specific spike proteins.
The spike proteins production stimulates the host’s-adaptive immune responses. Neutralizing antibodies and cellular CD-4, CD-8 memory cells are then developed.
The Oxford-AstraZeneca COVID-19 vaccine
- This vaccine is about 90% effective when the first dose is given at half-strength.
- The 2nd dose is given at full strength 28 days apart
- The vaccine is given intramuscularly
- Vaccine safety and efficacy trials were conducted in Brazil, UK. South Africa.
- Vaccine is well tolerated. Side effects are less in both severity, and incidence.
Most people are worried that DNA vaccines may be integrated into a vaccine recipient's chromosomal DNA, leading to the formation of cancer-causing, and or antibiotic resistance genes.
QUESTION: Do DNA vaccines cause genetic modification of recipient’s cells, and tissues?
ANSWER: No. This is because vaccine DNAs do not integrate into the recipient’s cell cycle. Normal cell division and growth in the recipient do not include the vaccine DNA. The only modification to the host is to stimulate them to make antibodies and T cells that will prevent infection with the virus or kill any covid-19 virus infected cells, to prevent or reduce disease severity.
ALEX SARKODIE, MD