Novavax is the first COVID-19 vaccine to use a more traditional technology than the mRNA vaccines from Pfizer and Moderna. It's being marketed as an alternative to the mRNA shots for some who might be hesitant to get them.
One of the big concerns about mRNA vaccines is that they can cause myocarditis or inflammation of the heart muscle. This is very rare, but it's something to watch out for if you get the mRNA shots or a similar protein-based vaccine.
RNA (pronounced 'rah-NO-vee') is the genetic code for proteins, the building blocks of cells. DNA contains this code, and mRNA, the messenger ribonucleic acid, carries it from the cell's nucleus to a protein factory.
The mRNA is made by an enzyme called RNA polymerase II in the nucleus of a cell. It uses a nucleotide sequence on the DNA as a template for making the mRNA, which carries a message from the nucleus to the cytoplasm, where it is read by ribosomes and translated into protein.
The mRNA sequence includes a 5' cap that binds proteins that initiate translation, and a 3' poly-adenylated tail, which promotes mRNA export from the nucleus. It also has a series of codons that are complementary to the sequence of nucleotides in the DNA.
The codons specify the order of amino acids that make up the polypeptide chain. An initiation codon begins polypeptide synthesis, and any one of three termination codons stops it.mRNA is a type of RNA that is used to make proteins.
It is produced in the nucleus, where DNA is transcribed into pre-mRNA by RNA polymerase. It is then exported from the nucleus to the cytoplasm and "read" by ribosomes, which use the mRNA to make protein.Unlike traditional DNA-based vaccines, which deliver small or inactivated doses of virus protein, mRNA-based vaccines comprise a single-stranded molecule that encodes the disease-specific antigen.
This mRNA strand is then transported into the body, activating the immune system to recognize and respond to it.Currently, mRNA vaccines are in clinical trials for many diseases, including HIV, influenza, rabies and Zika virus, and numerous hematologic and solid organ malignancies. The field of mRNA vaccines has made substantial strides over the past decade, with major technological innovation and research investment driving their development.
Vaccines are designed to protect against infections by preparing the immune system to attack specific viruses, bacteria, or other pathogens. They usually contain a piece of a viral protein that triggers the immune response when introduced into the body.mRNA vaccines are different from other vaccines because they use messenger RNA instead of a piece of a virus or bacteria.
mRNA is the molecule that essentially puts DNA instructions into action inside a cell.Because mRNA does not enter the nucleus, it does not change DNA and cannot interfere with the immune system. As a result, the immune system can mount a stronger and more effective response to mRNA than it would to the whole virus.
The safety of mRNA vaccines depends on several factors, including the type of mRNA used and the delivery method. For example, lipid nanoparticles are being investigated as a delivery vehicle for mRNA vaccines.Despite their early development, mRNA vaccines have shown promising efficacy against infectious diseases and several types of cancer in animal models.
Moreover, they are adaptable and versatile and can be manufactured in a scalable good manufacturing practice (GMP) manner.However, safety concerns have been raised. These include possible immunogenicity-related adverse reactions such as fever and skin rash.These concerns can be minimized by using a small, safe dose of mRNA, which is made through a cell-independent process and does not need to be inactivated.
Vaccines based on mRNA have been evaluated in multiple clinical trials against several cancers, including HPV16, glioblastoma and melanoma. These studies have demonstrated antigen-specific T-cell responses and prolonged disease-free survival in some cases.