London: Scientists have demonstrated that two small, stable antibody variants derived from the South American mammals llamas can neutralise the novel coronavirus in lab-cultured cells, an advance which may lead to the development of new therapeutics against COVID-19. The study, published in the journal Nature Structural & Molecular Biology, noted that the 'nanobodies' extracted from the llamas can prevent infection by blocking the interaction between the novel coronavirus and the protein ACE2, which it uses as a gateway to enter and infect cells.
Thus, the nanobodies, either alone, or in combination with other antibodies, may find application for passive immunisation of patients with severe COVID-19. The researchers explained that human antibodies, like those of most mammals, have two chains -- heavy and light -- but camelids, such as llamas, also possess an additional single heavy chain antibody variant, known as a nanobody. Nanobodies are small, stable and easily produced and thus often serve as alternatives to conventional antibodies for diagnostics and imaging, the scientists said.