A collection of infectious disease researchers at the California National Primate Research Center and the Center for Immunology and Infectious Diseases observed early immune response to SARS-CoV-2 in rhesus macaques. Their findings suggest vaccine developers should focus on promoting specialized immune cells called CD4 T follicular helper (Tfh) cells capable of targeting spike (S) and nucleocapsid (N) proteins associated with SARS-CoV-2.