How will vaccines fare vs. COVID strains?
The means to protect humans against COVID viruses is critical to our species and its future. The current vaccines get our bodies to produce proteins called immunoglobulins that bind to the virus and prevent it from infecting our cells. The two vaccines — Pfizer and Moderna — available to some of us in Humboldt County work by introducing a genetic sequence into our arms that is taken in by our cells and produces a protein that occurs on the outside of the COVID virus. This inspires our immune cells to produce antibodies that bind to the COVID virus and prevent it from infecting our cells. What is worrying is the effect of natural selection and evolution on the structure of COVID, and this is happening all over the globe now. Different COVID viruses have been found in South Africa, England, Brazil and the U.S. The Pfizer vaccine was tested in a lab and found to probably protect against infection by these variant viruses. It has not been tested in people yet.
Are there other ways that scientists have found to protect us from COVID viruses? Our bodies produce T cells that can detect and kill virus infected human cells. Recent studies have shown that virus-infected people produce T cells that focus on different parts of the virus’ proteins. Different people produce T cells that target different virus proteins. This makes natural selection and evolution much more difficult for the COVID virus. It is a much better approach than the production of antibodies which target a limited number of virus proteins. Studies of the South African COVID virus revealed that it is somewhat resistant to antibodies produced against previous viruses. However, T cells that have been produced against a prior infection continue to be effective against a new virus variant. So, this science may be a way for humans to develop broader resistance to these variant viruses despite their genetic changes. Interestingly, a California biotech company, Gritstone Oncology of Emeryville, is developing a vaccine that will induce T cells to produce antibodies that will protect us against variant viruses. Clinical trials of this vaccine are just getting started.
One last bit of advice about COVID: Some folks think that if they have been vaccinated they do not need to wear a mask to meet with others. However, if you have not been infected with COVID and are vaccinated, your body does not eliminate viruses that may not infect you, but are located in your nose and/or mouth. You can pass these viruses along to others if you do not wear a mask.
Now that’s deep
Technology has allowed scientists to look in many different places for new forms of life. A recent discovery was not anticipated as marine biogeographers were drilling a hole through 3,000 feet of ice on the edge of Antarctica to get a sample of the ocean’s floor below. They were not successful getting their core sample because a big rock was in the way. What they did discover were new forms of life living attached to the rock. They found two kinds of sponges and tube worms and barnacles. Their food probably filters down as other organisms like plankton, a diverse group of small marine species, die and drift down toward the bottom. It was a surprise to find these organisms as they live in total darkness and very cold water (28°F). One wonders whether this provides hope for finding evidence of life on Mars since we have just landed an amazing scientific machine, Perseverance,
there.
Doggone it
Lastly, an interesting paper in Science Magazine (https:// science.sciencemag.org/content/370/6516/522) reports a study of the origin of the relationship between people and dogs. Did this happen frequently and did dogs keep their relationships to wolves from whom they evolved in place? Dogs probably were domesticated sometime between 25,000 and 40,000 years ago based on genetic analyses. This study proposes that dogs likely evolved from using leftover food pieces from Paleolithic (starting about 8,500 BC) people in Eurasia. The genetic data also supports the hypothesis that dogs only evolved once from a nowextinct group of wolves. The genetic similarities between human populations also match the genetic patterns of dogs kept by these groups of people. So, when people moved, they also took their dogs with them. Another interesting genetic finding is that the evolution of dogs and their people sometimes followed similar evolutionary patterns. As the evolution of humans resulted in an increase the number of genes that code for an enzyme that allows us to get energy from starch, similar things happened in their dogs. That makes me wonder whether similar evolutionary changes are occurring now in us and our dog friends.
Rollin Richmond is an emeritus professor of biology and emeritus president at Humboldt State University. He has worked as an evolutionary geneticist at several universities during his career. (Full disclosure: He happens to be responsible for 50 percent of Times-Standard publisher John Richmond’s genetic makeup.) Questions or comments about this column can be sent to rollinr@humboldt.edu.