Extracts of Two Plants Shown to Block SARS-CoV-2 Spike Protein Mechanism

I don't know about you, but just looking at that picture makes me want to sneeze! But it turns out it has promise as something more than an annoying fall allergen.

Last month Emory University researchers published a study outlining their efforts to screen botanical agents to find any that have a protective effects against SARS-CoV-2. They scored hits with two extracts, one from the flowers of tall goldenrod (Solidago altissima) and another from the rhizomes of the eagle fern (Pteridium aquilinum).

To find them, scientists attached SARS-CoV-2 spike proteins to a payload that would make cells fluoresce. This provided a visual marker of when a cell had been penetrated. 

They then mixed these "virus-like particles" with specially engineered cells and various extracts from the Quave Natural Product Library. It contains thousands of botanical and fungal natural products extracted from plants collected at sites around the world.

They looked for cases where few cells were lit up and, voila! The goldenrod and eagle fern extracts were preventing penetration of the spike protein. 

They are now trying to identify and isolate the compounds for possible use as a therapeutic drug. The study reported effectiveness against the alpha, theta, delta and gamma variants. 

Interestingly, they did not say anything about omicron. It appears the study did not test that variant (I'm guessing the research started before that variant was around). If the compounds don't work for omicron they are probably not of much use since that variant and its progeny have crowded-out all the older variants.

The good news is that researchers think a compound in the extracts prevents the spike protein from twisting its way into cells. If so, there is reason to hope that a compound derived from the plants will have universal effectiveness against all known variants.


Popular posts from this blog

Looks Like Immune Responses are Enduring After All

Image
 For some time, public health officials have fretted about whether immunity to COVID-19, acquired via infection or vaccination would stick.  Studies showed rapid declines in antibodies during recovery from infection and thereafter . It turns out that this concern was overblown. A study just released says bone marrow plasma cells are a persistent source of protective antibodies, and that "circulating resting memory B cells directed against the S protein were detected in the convalescent individuals."   Another study , yet to be reviewed, suggests that vaccines boost this effect. In fact, some are suggesting this situation this could actually mean  lifetime immunity .   Whether the same thing happens with vaccination is not clear. Most estimates suggest that vaccine immunity will last about a year . More pessimistic estimates putting the protection period at six months .  The possible shorter time frame, plus the appearance of the new variants, have the vaccine makers working
Read more

Another One Bites the Dust

Image
Hi all. Stepping out of retirement for a moment to say that the day has finally arrived. After four years of successfully avoiding COVID-19 infection I had a positive test yesterday. Symptoms are very mild—I've had worse colds. The provider at urgent care said almost all the cases they are seeing are the same. Mild symptoms may also be due to the fact that I had the original vaccine then the two boosters. All this time I thought I might be a NOVID —one of those people who never get the bug. But no, it must have been my assiduous mask wearing and avoidance of high-risk situations when things were bad. So here's double middle fingers to all the kooks who think masks don't work (I've not been wearing masks for months now). I don't know what variant I have but it's likely JN.1. It is said to be extraordinarily contagious and accounts for 60% of cases worldwide . It also tends to produce mild infections like the one I have.  This article claims that right now every
Read more

AZ Pandemic Numbers Summary for the Seven Days Ending November 9: Everything is Going South

Image
Here are the Arizona pandemic numbers and graph of statewide cases for the seven day period ending yesterday: Well this isn't good. The lull seems to be over. Virtually every number is up, both over a week and over four weeks. The most worrisome is hospital beds, which have been steadily trending up over the last several weeks.  Wastewater signals are all up except Tempe (dashboard is up again) which after going up last week (from 41 to 100) decreased by about 10%. The increases are worrisome because the latest data from ASU's Lim Lab (last updated October 31), where they sequence PCR samples to identify variants, shows that only about 46% of sequences showed BA.5. That is one of the Omicron variants the new bivalent vaccine was designed to protect against.  All the rest of the samples are BA.2.75 (7.7%), which I flagged several weeks ago, and BQ,1.1 (15.4%), and BQ.1 (30.8%), both of which I blogged about a couple weeks ago.  Those, new research confirms , are much more lik
Read more