What is the mechanism of Elasomeran?

Elasomeran, also known as mRNA-1273, is the technical name for the Moderna COVID-19 vaccine. To understand the mechanism of Elasomeran, it’s essential to grasp the basics of how mRNA vaccines work and the specific components and processes involved in this particular vaccine.

mRNA vaccines represent a novel approach to immunization. Traditional vaccines often use weakened or inactivated forms of a virus to stimulate an immune response. In contrast, mRNA vaccines use a small piece of the virus's genetic material to instruct cells in the body to produce a protein that triggers an immune response.

Elasomeran employs messenger RNA (mRNA) that encodes the spike (S) protein of the SARS-CoV-2 virus, which is responsible for COVID-19. The spike protein is a key structure that the virus uses to enter human cells. Here is a step-by-step explanation of the mechanism of action of Elasomeran:

1. **mRNA Delivery**: The mRNA in Elasomeran is encapsulated within lipid nanoparticles. These lipid nanoparticles serve as delivery vehicles, protecting the fragile mRNA molecules from degradation and facilitating their entry into human cells. Once administered via intramuscular injection, the lipid nanoparticles transport the mRNA into the cytoplasm of host cells.

2. **Translation into Protein**: Once inside the host cells, the mRNA is translated by the cellular machinery to produce the spike protein. Ribosomes, the protein-synthesizing structures in cells, read the mRNA sequence and assemble the corresponding spike protein.

3. **Antigen Presentation**: The newly produced spike proteins are then processed by the host cells and presented on their surface via major histocompatibility complex (MHC) molecules. This presentation is crucial for alerting the immune system to the presence of a foreign protein.

4. **Immune System Activation**: The display of spike proteins on the surface of cells triggers an immune response. Dendritic cells, which are a type of antigen-presenting cell, play a significant role in this process. They capture the spike protein fragments and present them to T cells and B cells, the key players in the adaptive immune system.

5. **T Cell Response**: The presentation of spike protein by dendritic cells activates helper T cells, which release cytokines and further stimulate the immune response. Cytotoxic T cells may also be activated, which are capable of directly destroying infected cells presenting the spike protein antigen.

6. **B Cell Response and Antibody Production**: The spike protein also stimulates B cells to produce antibodies. These antibodies are specific to the spike protein and can neutralize the virus by binding to it and preventing it from entering human cells. Some of these B cells become memory B cells, which persist in the body and provide long-term immunity by rapidly producing antibodies if the virus is encountered again in the future.

7. **Formation of Memory Cells**: The immune response culminates in the formation of memory T cells and B cells. These memory cells "remember" the spike protein and allow for a faster and more robust response if the individual is exposed to the SARS-CoV-2 virus in the future.

The effectiveness of Elasomeran has been demonstrated in clinical trials, reducing the severity of COVID-19 and preventing the spread of the virus. The mRNA platform not only proved to be effective but also allowed for rapid development and production in response to the pandemic.

In summary, Elasomeran works by delivering mRNA encoding the SARS-CoV-2 spike protein into host cells, where it is translated into the spike protein, initiating an immune response. This response includes the activation of T cells and B cells, the production of antibodies, and the formation of memory cells that provide long-lasting immunity. This mechanism highlights the innovative approach of mRNA vaccines in combating infectious diseases.