Deep Dive into Alpaca’s Nanobody Repertoire Identifies Potent SARS-CoV-2 Neutralizers

A man wearing a protective face mask walks past an illustration of a virus outside a regional science center amid the coronavirus disease (COVID-19) outbreak, in Oldham, Britain August 3, 2020. (Reuters)
A man wearing a protective face mask walks past an illustration of a virus outside a regional science center amid the coronavirus disease (COVID-19) outbreak, in Oldham, Britain August 3, 2020. (Reuters)
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Deep Dive into Alpaca’s Nanobody Repertoire Identifies Potent SARS-CoV-2 Neutralizers

A man wearing a protective face mask walks past an illustration of a virus outside a regional science center amid the coronavirus disease (COVID-19) outbreak, in Oldham, Britain August 3, 2020. (Reuters)
A man wearing a protective face mask walks past an illustration of a virus outside a regional science center amid the coronavirus disease (COVID-19) outbreak, in Oldham, Britain August 3, 2020. (Reuters)

Researchers at Karolinska Institutet have developed a novel strategy for identifying potent miniature antibodies, so-called nanobodies, against emerging SARS-CoV-2 variants.

The approach led to the discovery of multiple nanobodies that in cell cultures and mice effectively blocked infection with different SARS-CoV-2 variants. The findings, which are described in the journals Nature Communications and Science Advances, could pave the way for new treatments against COVID-19.

“With the help of advanced laboratory techniques, we were able to identify a panel of nanobodies that very effectively neutralized several variants of SARS-CoV-2,” says Gerald McInerney, professor at the Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, and joint senior author of both studies.

Despite the roll-out of vaccines and antivirals, the need for effective therapeutics against severe COVID-19 infection remains high.

Nanobodies — which are fragments of antibodies that occur naturally in camelids and can be adapted for humans — are promising therapeutic candidates as they offer several advantages over conventional antibodies. For example, they have favorable biochemical properties and are easy to produce cost-effectively at scale.

In the now published studies, the labs of Gerald McInerney and Ben Murrell, also at MTC, identify several potent nanobodies derived from an alpaca immunized with SARS-CoV-2 antigens.

The first report in Nature Communications describes a single nanobody, Fu2 (named after the alpaca Funny), that significantly reduced the viral load of SARS-CoV-2 in cell cultures and mice.

Using electron cryo-microscopy, the researchers found that Fu2 naturally binds to two separate sites on the viral spike, thus inhibiting the virus’ ability to enter the host cell.

This part of the study was conducted in collaboration with Hrishikesh Das and Martin Hällberg at the Department of Cell and Molecular Biology at Karolinska Institutet.

The researchers next delved deeper into the alpaca’s nanobody repertoire by combining a range of advanced laboratory techniques and computational methods, resulting in a library of nanobodies described in detail.

The results, presented in Science Advances, revealed additional nanobodies that in cell cultures and mice effectively cross-neutralized both the founder and beta variant of SARS-CoV-2 and even neutralized the more distantly related SARS-CoV-1.

“These nanobodies represent promising therapeutic candidates against several SARS-CoV-2 variants,” says first author Leo Hanke, a postdoctoral researcher who established the nanobody technology in the McInerney group.

The researchers are currently applying the same techniques to identify which nanobodies from this set are best able to neutralize Omicron, the now dominating SARS-CoV-2 variant.



Sudan's Historic Acacia Forest Devastated as War Fuels Logging

Little is left of the once sprawling acacia forest south of Sudan's capital. Ebrahim Hamid / AFP
Little is left of the once sprawling acacia forest south of Sudan's capital. Ebrahim Hamid / AFP
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Sudan's Historic Acacia Forest Devastated as War Fuels Logging

Little is left of the once sprawling acacia forest south of Sudan's capital. Ebrahim Hamid / AFP
Little is left of the once sprawling acacia forest south of Sudan's capital. Ebrahim Hamid / AFP

Vast stretches of a once-verdant acacia forest south of Sudan's capital Khartoum have been reduced to little more than fields of stumps as nearly three years of conflict have fueled deforestation.

What was once a 1,500-hectare natural reserve has been "completely wiped out", Boushra Hamed, head of environmental affairs for Khartoum state, told AFP.

Al-Sunut forest had long served as a haven for migratory birds and a vital green shield against the Nile's seasonal floods.

"During the war, Khartoum state has lost 60 percent of its green cover," Hamed said, describing how century-old trees "were cut down with electric saws" for commercial timber and charcoal production.

Where tall acacias once cast cool shade over a wetland just upstream from the confluence of the Blue and White Nile, barren ground now lies exposed, criss-crossed by people gathering whatever wood remains.

Hamed called it "methodical destruction", though the perpetrators remain unknown and there has been no investigation.

Similar devastation is unfolding across several regions -- including western Darfur, neighboring Kordofan and the central states of Sennar and Al-Jazirah -- as insecurity and economic collapse drive unchecked logging, according to Sudan's Forests National Corporation.

According to a 2019 study by the Nairobi-based African Forest Forum, Sudan had already lost nearly half of its forested land since 1960 due to agricultural expansion, firewood collection and overgrazing.

By 2015, the country ranked among Africa's least forested nations, with around 10 percent of its territory still covered by woodland, the study said.

The report had also warned of further degradation if reforestation and sustainable management efforts were not implemented -- concerns now compounded by the ongoing conflict.

- 'Barrier' -

Aboubakr Al-Tayeb, who oversees Khartoum's forestry administration, said the damage "affects not only Khartoum, but Sudan and the wider African continent."

"The forest was home to several migratory species from Europe," he told AFP.

More than a hundred bird species, including ducks, geese, terns, ibis, herons, eagles and vultures, had been recorded in the area, alongside monkeys and small mammals.

Al-Nazir Ali Babiker, an agronomist, said the loss of tree cover could cause more severe seasonal flooding because the "forest acted as a barrier" against rising waters.

Flooding strikes Sudan every year, destroying homes, farmland and infrastructure and leaving many families with no choice but to flee to safer areas.

The war in Sudan, which erupted in April 2023, has already killed tens of thousands, displaced 11 million and shattered critical infrastructure.

Before the fighting, forests supplied roughly 70 percent of Sudan's energy consumption, primarily through charcoal and firewood, according to data from the African Forest Forum.

Al-Sunut had also been a popular leisure spot for Khartoum residents.

"We used to come in groups to study and have a good time," recalls Adam Hafiz Ibrahim, a student at Omdurman Islamic University.

Today, wood gatherers have supplanted the usual walkers. Disregarding army notices alerting them to landmines, men and women traverse the dry, open ground that now stands where the ancient forest once grew.

"We're not cutting the trees. We just pick up whatever wood's already on the ground to use for the fire," said Nafisa, a woman in her forties navigating the dry grasslands.

"We found the trees down. We collect the wood to sell to bakeries and families," said Mohamed Zakaria, a construction worker who lost his job because of the war.

Experts say that the economic hardship caused by the war combined with a lack of enforcement has encouraged logging.

"The logging continues, because those responsible for forest protection cannot access many areas," said Mousa el-Sofori, head of Sudan's Forests National Corporation.

Efforts to replant acacias are underway, Tayeb of the Khartoum forestry administration said, but seedlings grow slowly and can take years to mature.

Restoring the lost woodlands would be "long and costly", said Sofori.

"Some of these forests were centuries old," he added.


Coffee Regions Hit by Extra Days of Extreme Heat, Say Scientists 

17 April 2012, North Rhine-Westphalia, Vluyn: A general view of Arabica Coffee beans. (dpa)
17 April 2012, North Rhine-Westphalia, Vluyn: A general view of Arabica Coffee beans. (dpa)
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Coffee Regions Hit by Extra Days of Extreme Heat, Say Scientists 

17 April 2012, North Rhine-Westphalia, Vluyn: A general view of Arabica Coffee beans. (dpa)
17 April 2012, North Rhine-Westphalia, Vluyn: A general view of Arabica Coffee beans. (dpa)

The world's main coffee-growing regions are roasting under additional days of climate change-driven heat every year, threatening harvests and contributing to higher prices, researchers said Wednesday.

An analysis found that there were 47 extra days of harmful heat per year on average in 25 countries representing nearly all global coffee production between 2021 and 2025, according to independent research group Climate Central.

Brazil, Vietnam, Colombia, Ethiopia and Indonesia -- which supply 75 percent of the world's coffee -- experienced on average 57 additional days of temperatures exceeding the threshold of 30C.

"Climate change is coming for our coffee. Nearly every major coffee-producing country is now experiencing more days of extreme heat that can harm coffee plants, reduce yields, and affect quality," said Kristina Dahl, Climate Central's vice president for science.

"In time, these impacts may ripple outward from farms to consumers, right into the quality and cost of your daily brew," Dahl said in a statement.

US tariffs on imports from Brazil, which supplies a third of coffee consumed in the United States, contributed to higher prices this past year, Climate Central said.

But extreme weather in the world's coffee-growing regions is "at least partly to blame" for the recent surge in prices, it added.

Coffee cultivation needs optimal temperatures and rainfall to thrive.

Temperatures above 30C are "extremely harmful" to arabica coffee plants and "suboptimal" for the robusta variety, Climate Central said. Those two plant species produce the majority of the global coffee supply.

For its analysis, Climate Central estimated how many days each year would have stayed below 30C in a world without carbon pollution but instead exceeded that level in reality -- revealing the number of hot days added by climate change.

The last three years have been the hottest on record, according to climate monitors.


Dog Gives Olympics Organizers Paws for Thought

A dog wanders on the ski trail during the women's team cross country free sprint qualification event of the Milano Cortina 2026 Winter Olympic Games at Tesero Cross-Country Skiing Stadium in Lago di Tesero (Val di Fiemme), on February 18, 2026. (Photo by Anne-Christine POUJOULAT / AFP)
A dog wanders on the ski trail during the women's team cross country free sprint qualification event of the Milano Cortina 2026 Winter Olympic Games at Tesero Cross-Country Skiing Stadium in Lago di Tesero (Val di Fiemme), on February 18, 2026. (Photo by Anne-Christine POUJOULAT / AFP)
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Dog Gives Olympics Organizers Paws for Thought

A dog wanders on the ski trail during the women's team cross country free sprint qualification event of the Milano Cortina 2026 Winter Olympic Games at Tesero Cross-Country Skiing Stadium in Lago di Tesero (Val di Fiemme), on February 18, 2026. (Photo by Anne-Christine POUJOULAT / AFP)
A dog wanders on the ski trail during the women's team cross country free sprint qualification event of the Milano Cortina 2026 Winter Olympic Games at Tesero Cross-Country Skiing Stadium in Lago di Tesero (Val di Fiemme), on February 18, 2026. (Photo by Anne-Christine POUJOULAT / AFP)

A dog decided he would bid for an unlikely Olympic medal on Wednesday as he joined the women's cross country team free sprint in the Milan-Cortina Games.

The dog ran onto the piste in Tesero in northern Italy and gamely, even without skis, ran behind two of the competitors, Greece's Konstantina Charalampidou and Tena Hadzic of Croatia.

He crossed the finishing line, his moment of glory curtailed as he was collared by the organizers and led away -- his owner no doubt will have a bone to pick with him when they are reunited.