This leads us to the method being employed here. In this instance, the researchers incorporated the antibody genes into a circular DNA loop known as a plasmid. This is sufficient to prevent the DNA from being immediately broken down and to facilitate the conversion of antibody genes into proteins. However, it does not assist in delivering the DNA into cells.
The research group, comprised of individuals from both a biotech firm and academic laboratories, employed a commercial injection system that combines the DNA injection with brief bursts of electricity. The electrical pulses disrupt the cell membrane, enabling the plasmid DNA to enter the cells. Based on tests conducted on animals, this method in muscle cells is adequate to transform the muscles into factories that generate numerous broadly neutralizing antibodies.
The new research aimed to evaluate the safety of this approach in humans. The team enlisted 44 participants, experimenting with different dosages of two antibody-producing plasmids and injection intervals. All but four participants completed the study; three of those who withdrew had been involved in a regimen where the electric pulses were administered very rapidly, which turned out to be uncomfortable. Thankfully, this did not appear to impact the antibody production.
Although there were several adverse reactions, most were linked to the injection itself: localized muscle pain, the formation of a scab afterward, and redness of the skin. The most significant issue seemed to be a single instance of moderate muscle pain that lasted a few days.
In all but one participant, the injection resulted in consistent production of the two antibodies for a minimum of 72 weeks following the injection; the one exception produced only one of the two antibodies. That’s “at least” 72 weeks because the testing was halted at that point—there was no indication that the levels were decreasing at that time. Administering additional DNA resulted in greater variability in the quantity of antibodies produced, but that amount quickly plateaued. More injections overall also increased the level of antibody production. However, even the most basic procedure—two injections of the lowest concentration tested—produced significant and stable antibody levels.
