Answer:
1. The active compound in the Pfizer-BioNTech COVID-19 vaccine is BNT162b2, a lipid nanoparticle-formulated, nucleoside-modified RNA vaccine. The active compound in the Johnson & Johnson COVID-19 vaccine is Ad26.COV2.S, a recombinant, replication-incompetent adenovirus type 26 vector expressing the SARS-CoV-2 spike protein.
2. The administration of these vaccines results in protection against COVID-19 through an immune response. In the Pfizer vaccine, the mRNA instructs the cells to make a harmless piece of the spike protein found on the surface of the SARS-CoV-2 virus. The immune system recognizes this protein as foreign and mounts an immune response. If the person is later exposed to the virus, their immune system can recognize the spike protein and respond more effectively. The Johnson & Johnson vaccine works similarly, but instead of mRNA, it uses a harmless adenovirus to deliver the spike protein gene into cells.
3. In the case of the Johnson & Johnson vaccine, the following processes occur:
- The adenovirus enters the cell.
- The cell's machinery reads the genetic instructions to produce the spike protein.
- The spike protein is displayed on the cell surface.
- The immune system recognizes the spike protein as foreign and mounts an immune response.
- Memory cells are created. If the person is exposed to the SARS-CoV-2 virus in the future, these memory cells will recognize the spike protein and prompt a quick immune response.
4. The Pfizer vaccine uses mRNA, which requires a transcription process from a DNA template in its manufacturing process. This transcription process is conducted ex vivo (outside the organism). The Johnson & Johnson vaccine, on the other hand, uses a DNA vector (adenovirus), which does not require this transcription step in its manufacturing process. Instead, the DNA is directly inserted into the adenovirus vector.
5. To obtain the recombinant DNA plasmid:
- The SARS-CoV-2 RNA is converted to complementary DNA (cDNA) using reverse transcriptase.
- The cDNA corresponding to the spike protein gene is amplified and isolated.
- This cDNA is inserted into a DNA plasmid using restriction enzymes and DNA ligase. This forms the recombinant DNA plasmid.
- The plasmid is introduced into bacteria (usually E. coli) for amplification.
6. The statement that the Pfizer vaccine can change your DNA is not valid. The mRNA in the Pfizer vaccine never enters the cell's nucleus, where the DNA is located. The mRNA is transcribed in the cytoplasm and quickly breaks down after it is used. It does not have the ability to integrate into the genome and therefore cannot change a person's DNA.