How to mutate Delta, Kappa strains to overcome Covid-19 vaccine

A team of American scientists has discovered how Delta and Kappa strains trick the recognition of antibodies, thereby overcoming the immune system created by the vaccine.

Scientists from the University of Washington School of Medicine took blood samples from 37 people aged 22-66. These people have had 2 doses of Moderna or Pfizer-BioNTech vaccine, or one dose of Johnson & Johnson vaccine, according to India Times.

Analytical data show that the Delta, Delta Plus and Kappa strains reduce the virus-neutralizing effect of vaccine-generated antibodies.

The Delta Plus mutation causes the strongest decrease in antibody potency. Antibodies in about 50% of people vaccinated with the Johnson & Johnson vaccine lost their potency against the strains, test results showed.

Although the Kappa and Delta Plus strains are more resistant to vaccine-induced antibodies, Delta is currently the dominant virus strain on a global scale.

The Delta, Delta Plus and Kappa strains have the ability to overcome the immune system of vaccinated people. (Photo: AP).

Current vaccines mainly focus on glycoprotein spikes on the surface of the SARS-CoV-2 virus. The glycoprotein spike on the virus contains an N-terminal that enhances cell adhesion, and a receptor-binding end that helps the virus bind to the ACE2 receptor on the host cell.

Most antibodies produced by the vaccine will attack some specific site of the two ends mentioned above. Thus, with strains showing mutations at the N-terminal and receptor-binding ends, as occurred in Delta and Kappa, the antibody is deactivated.

However, by closely observing the main infection structure on the mutants, scientists have identified an antibody with the symbol S2X303 with outstanding virus neutralization efficiency, with the ability to attack many strains.

By figuring out how this antibody interacts with the N-terminal on the virus, the scientists can determine how the antibody kills the virus.

The identification of antibodies capable of neutralizing many strains could help scientists develop new-generation Covid-19 vaccines, creating a strong and effective immune system against more viral strains.