A team of researchers has developed a novel strategy for identifying potent miniature antibodies, so-called nanobodies, against emerging SARS-CoV-2 variants.

The approach, published in the journal Science Advances, led to the discovery of multiple nanobodies that in cell cultures and mice effectively blocked infection with different SARS-CoV-2 variants.

"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," said researcher Gerald McInerney from Karolinska Institutet in Sweden.

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 favourable biochemical properties and are easy to produce cost-effectively at scale.

In the now published studies, the labs of a few researchers identify several potent nanobodies derived from an alpaca immunised with SARS-CoV-2 antigens.

The results 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.