When the COVID-19 pandemic first began, there was a scramble to source and validate the various biospecimens that would be required to develop diagnostic tests, therapeutic interventions, and vaccine candidates. While many human specimens were collected from health clinics, hospitals and testing centers throughout the world, other test subjects were also needed. Various animal species have proven significant in developing disease infection models, therapies, and vaccine development trials. Here are some notable developments.
SARS-CoV-2 infection protects against rechallenge in rhesus macaques by Chandrashekar et alPrimary exposure to SARS-CoV-2 protects against reinfection in rhesus macaques by Deng et al
Non-human primates are critical models for biomedical researchers due to their phylogenetic proximity to humans, with genetics, physiology, immunogenetics and age-related changes in immune function that mimic our own. These two papers demonstrated that in a rhesus macaque model for SARS-CoV-2, exposure to the virus protects against subsequent reinfection via immunological control.
Murine models are invaluable in research and development due to their phylogenetic similarity to humans, the ease of maintaining and breeding them in the laboratory and the availability of many inbred and genetically modified strains. While there are limitations due to evolved differences in genetic linking of pathways, physiology and integrated immune functions, mice and other rodents are extremely common — and useful — for human disease research.
In this study, a new model system was developed for SARS-CoV-2 vaccine and therapeutic studies by using an hACE2 (the virus receptor) expressing adenovirus to transduce mice. Through this model, any strain of mice susceptible to the adenovirus transduction can be used as a SARS-CoV-2 model, including immunocompetent, immunodeficient and any genetically inbred or humanized strain. This significantly decreases the time that would normally be required to create susceptible strains through inbred backcrosses.
Llamas produce single-domain antibodies, or nanobodies, which are roughly a quarter of the size of typical human antibodies1. Now, researchers are exploring the use of specifically induced nanobodies as a therapeutic agent against pulmonary infections, such as the flu and SARS-CoV-22. This study used previous work in understanding the immune response to SARS and MERS to select and further engineer a nanobody that binds to the SARS-CoV-2 spike protein, thus preventing the virus from entering cells in laboratory experiments.
Cows may not seem like a typical research animal, but they are useful when it comes to making recombinant antibodies. This is not only due to their large size and blood volume, but also their large production of antibodies per milliliter of blood. SAB Biotherapeutics uses cows to produce recombinant polyclonal antibodies for both the treatment of infected COVID-19 patients and potentially for passive immunity for those at risk.
These studies represent just a fraction of the COVID-19 research that is currently ongoing. As biomedical researchers continue to develop novel in vitro models that mimic a variety of human diseases and conditions, BioIVT will continue to support these efforts with access to tissues and biofluids from all commercially available animal models. We invite you to review our customizable blood-derived and non-blood derived biospecimens that will advance your research into gene expression, protein binding and more.
- Naturally occurring antibodies devoid of light chains. Hamers-Casterman C, Atarhouch T, Muyldermans S, Robinson G, Hamers C, Songa EB, Bendahman N, Hamers R. Nature. 1993 Jun 3;363(6428):446-448.
- Universal protection against influenza infection by a multidomain antibody to influenza hemagglutinin. Laursen NS, Friesen RHE, Zhu X, Jongeneelen M, Blokland S, Vermond J, van Eijgen A, Tang C, van Diepen H, Obmolova G, van der Neut Kolfschoten M, Zuijdgeest D, Straetemans R, Hoffman RMB, Nieusma T, Pallesen J, Turner HL, Bernard SM, Ward AB, Luo J, Poon LLM, Tretiakova AP, Wilson JM, Limberis MP, Vogels R, Brandenburg B, Kolkman JA, Wilson IA. Science. 2018 Nov 2;362(6414):598-602.