cells . If it ’ s already infected some of the cells , the immune system destroys those cells to keep the agent from multiplying . Haczku explains that the responsiveness of the immune system to a vaccine is measured by the number of antibodies the body is able to mount in response to the injection , which , in turn , determines the effectiveness of the vaccine .
Once a vaccine has been developed , it must go through a rigorous testing process . In the preclinical stage , a vaccine is tested for efficacy on animal models ( test subjects ) before moving on to human subjects . Mice , rats and nonhuman primates are the most used species for testing COVID-19 vaccines , since rodents can be genetically altered to be susceptible to the virus , and primates — specifically rhesus macaque monkeys — most closely resemble humans in both their immune response and development of symptoms when infected with SARS-CoV-2 .
In August , the National Institutes of Health awarded the UC Davis Mouse Biology Program a $ 1.2 million grant to create mice that are susceptible to COVID-19 ( they aren ’ t naturally ) and distribute them to other researchers . On the primate side , rhesus macaque testing for COVID-19 has been underway since March at the on-campus California National Primate Research Center , one of seven such centers across the country funded by the NIH developed to breed , house , care for and study primates for medical and behavioral research . What distinguishes UC Davis ’ research is the CNPRC ’ s unique collection of primates at various stages of health and age , a key factor in making sure a vaccine will work to protect the breadth of the human population , including those with underlying health conditions .
“ Animal models are extremely important , because if we can provoke a classic immune response in an animal , we can use that information to develop a vaccine ,” explains Dr . Smita Iyer , an immunologist and assistant professor at the CNPRC , the UC Davis School of Veterinary Medicine , and the Center for Immunology and Infectious Diseases .
Dr . Smita Iyer , an immunologist and assistant professor at the UC Davis School of Veterinary Medicine , is studying how helper T cells ( a type of immune cell that activates the body ’ s immune response ) work against SARS-CoV-2 .
“ Animal models are extremely important , because if we can provoke a classic immune response in an animal , we can use that information to develop a vaccine . Human studies are harder to control depending on when you get samples and how much you get . Those ambiguities are removed in an animal study .”
DR . SMITA IYER Immunologist and assistant professor UC Davis School of Veterinary Medicine
December 2020 | comstocksmag . com 31