In Pictures: Spring Desserts

Vaccine-induced Antibodies May be Less Effective Against Several New SARS-CoV-2 Variants

Rachel Leeson wrote . . . . . . . . .

SARS-CoV-2, the virus that causes COVID-19, has mutated throughout the pandemic. New variants of the virus have arisen throughout the world, including variants that might possess increased ability to spread or evade the immune system. Such variants have been identified in California, Denmark, the U.K., South Africa and Brazil/Japan. Understanding how well the COVID-19 vaccines work against these variants is vital in the efforts to stop the global pandemic, and is the subject of new research from the Ragon Institute of MGH, MIT and Harvard and Massachusetts General Hospital.

In a study recently published in Cell, Ragon Core Member Alejandro Balazs, PhD, found that the neutralizing antibodies induced by the Pfizer and Moderna COVID-19 vaccines were significantly less effective against the variants first described in Brazil/Japan and South Africa. Balazs’s team used their experience measuring HIV neutralizing antibodies to create similar assays for COVID-19, comparing how well the antibodies worked against the original strain versus the new variants.

“We were able to leverage the unique high-throughput capacity that was already in place and apply it to SARS-CoV-2,” says Balazs, who is also an assistant professor of Medicine at Harvard Medical School and assistant investigator in the Department of Medicine at MGH. “When we tested these new strains against vaccine-induced neutralizing antibodies, we found that the three new strains first described in South Africa were 20-40 times more resistant to neutralization, and the two strains first described in Brazil and Japan were five to seven times more resistant, compared to the original SARS-CoV-2 virus.”

Neutralizing antibodies, explains Balazs, work by binding tightly to the virus and blocking it from entering cells, thus preventing infection. Like a key in a lock, this binding only happens when the antibody’s shape and the virus’s shape are perfectly matched to each other. If the shape of the virus changes where the antibody attaches to it – in this case, in SARS-CoV-2’s spike protein – then the antibody may no longer be able to recognize and neutralize the virus as well. The virus would then be described as resistant to neutralization.

“In particular,” says Wilfredo Garcia-Beltran, MD, PhD, a resident physician in the Department of Pathology at MGH and first author of the study, “we found that mutations in a specific part of the spike protein called the receptor binding domain were more likely to help the virus resist the neutralizing antibodies.” The three South African variants, which were the most resistant, all shared three mutations in the receptor binding domain. This may contribute to their high resistance to neutralizing antibodies.

Currently, all approved COVID-19 vaccines work by teaching the body to produce an immune response, including antibodies, against the SARS-CoV-2 spike protein. While the ability of these variants to resist neutralizing antibodies is concerning, it doesn’t mean the vaccines won’t be effective.

“The body has other methods of immune protection besides antibodies,” says Balazs. “Our findings don’t necessarily mean that vaccines won’t prevent COVID, only that the antibody portion of the immune response may have trouble recognizing some of these new variants.”

Like all viruses, SARS-CoV-2 is expected to continue to mutate as it spreads. Understanding which mutations are most likely to allow the virus to evade vaccine-derived immunity can help researchers develop next-generation vaccines that can provide protection against new variants. It can also help researchers develop more effective preventative methods, such as broadly protective vaccines that work against a wide variety of variants, regardless of which mutations develop.

Source: Massachusetts General Hospital

Polaroid Made a Pen That Lets You Draw Pieces of Candy

Andrew Liszewski wrote . . . . . . . . .

There are 3D-printing pens that let prolific doodlers turn their drawings into three-dimensional sculptures, but all users are really left with is a piece of art. Polaroid’s taking 3D-printing pens one step further by replacing extruded plastic with melted candy so that when your masterpiece is complete, you can eat it.

The Polaroid CandyPlay 3D Pen isn’t an entirely new idea; we’ve already seen 3D printers upgraded so they extrude edible material instead of PLA plastic, and kids have had access to a printing pen that extrudes melted chocolate since 2015. What sets the CandyPlay 3D Pen apart is that it’s entirely freehand, so anyone can dive right in and start creating without having to learn to use software to design or prep a 3D model first. And unlike the chocolate pen, the candy material used here is rigid enough when cool that it can be layered to slowly build up 3D models.

Out of the box the CandyPlay 3D Pen, which sells for about US$50, comes with four strawberry-flavored candy cartridges that appear to be much easier and cleaner to load than trying to dump a handful of sugar into the pen. In fact, while there are six different sweet flavors to choose from (strawberry, orange, apple, grape, lemon, and cola) the edible printing material is apparently sugar-free.

The candy cartridges don’t look especially large, maybe the size of a couple of Jolly Ranchers, which means that if 3D candy becomes your artistic medium of choice, you’ll probably go through them rather quickly. Refills for each flavor are available, but at about US$28 for 40 candy cartridges (or around US$32 for the multi-flavor 48-pack), it sounds like Polaroid is taking the inkjet printer route and making most of its money on the refills. If the device catches on, however, you can expect to see cheaper third-party refills become available at more competitive prices.

Using Polaroid’s CandyPlay 3D Pen seems easy enough: You plug it in (there’s no rechargeable battery), wait for an LED to tell you the heating mechanism is warm enough, and then press a button to intermittently extrude the sticky material, or set it to flow freely until you tell it to stop if you don’t feel like holding down a button all the time. What you create is completely up to your imagination and skill level, but Polaroid recommends starting with some traceable stencils it will provide for download on its site so users can familiarize themselves with how the pen works. It’s likely not as easy as using a ballpoint pen or a Sharpie, but the payoff seems more delicious than trying to lick ink off a page.

Source: Gizmodo

Science Reveals Why Tea Is Good for Your Heart

If a nice hot cup of tea sounds good to you, there’s even more reason to enjoy one now. Scientists have gained new insight into how tea helps lower blood pressure, perhaps pointing the way to new types of blood pressure medications.

The researchers found that certain compounds in both black and green tea help relax blood vessels by activating ion channel proteins in the walls of blood vessels.

Two catechin-type flavonoid compounds (epicatechin gallate and epigallocatechin-3-gallate) each activate a specific type of ion channel protein named KCNQ5, which is found in the smooth muscle that lines blood vessels.

Previous research suggested that tea catechins activated KCNQ5, and this new University of California, Irvine (UCI), study confirms that.

People worldwide have about 2 billion cups of tea each day. And tea is second only to water in terms of the volume consumed globally, the researchers said in background notes.

Black tea is often mixed with milk. In laboratory tests, the UCI team found that the addition of milk to black tea prevented the beneficial KCNQ5-activating effects of tea.

However, we “don’t believe this means one needs to avoid milk when drinking tea to take advantage of the beneficial properties of tea. We are confident that the environment in the human stomach will separate the catechins from the proteins and other molecules in milk that would otherwise block catechins’ beneficial effects,” study co-author Geoffrey Abbott said in a university news release. He’s a professor in the department of physiology and biophysics in the UCI School of Medicine.

Previous studies have shown that even when milk is added, tea retains its blood pressure-lowering benefits.

The new study also found that warming green tea to 35 degrees Celsius (95 degrees Fahrenheit) changes its chemical composition in a way that makes it more effective at activating KCNQ5.

“Regardless of whether tea is consumed iced or hot, this temperature is achieved after tea is drunk, as human body temperature is about 37 degrees Celsius,” Abbott said. “Thus, simply by drinking tea we activate its beneficial, antihypertensive properties.”

The findings were published in the March issue of the journal Cellular Physiology and Biochemistry.

Source: HealthDay

Apple Charlotte

Ingredients

2 lb firm apples
3 cup butter or margarine
2 tablespoons potato starch
4 tablespoons sugar
1 teaspoon cinnamon
1/4 oz vanilla sugar
1-1/2 cups apricot jam
1-1/2 lb white sandwich bread or ladyfingers
confectioners sugar and 1-2 glasses rum to serve

Method

  1. Peel, core and quarter the apples. Put them in a pan with 2 tablespoons of the butter and cook until pureed, stirring occasionally with a wooden spoon.
  2. Add the starch, blended with a little water, the sugar, cinnamon and vanilla sugar and continue cooking the mixture over high heat until it is a thick puree.
  3. Stir in 3 tablespoons of the apricot jam and let the mixture cool completely.
  4. Trim the crust off the bread slices, cut 6 slices into triangles and halve the other slices.
  5. Melt the remaining butter or margarine in a pan and dip the slices quickly into it.
  6. Line a high-sided buttered mold or charlotte mold with some of the bread slices, using the triangles for the bottom and overlapping the rectangles around the sides.
  7. Brush the bread slices with the remaining apricot jam, pour in the apple puree and cover with a layer of bread slices.
  8. Bake the charlotte in a hot oven (400°F) for about 1 hour.
  9. Unmold on a warm serving platter and sprinkle with confectioners’ sugar.
  10. Heat the rum, pour it on the charlotte and flame.

Makes 1 charlotte.

Source: The Cook’s Book


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