Editorial on the Research Topic Preclinical macaque models of viral diseasesPreclinical macaque models of viral diseases are among the most translatable animal models to human patients (1-3). These models have key benefits including rigorously controlled timing of manipulations, routes and doses of infectious agents and interventions, age and health status of animals, etc., which can serve to eliminate important sources of variability and potential confounding variables. Macaques have significant genetic and physiological similarities to humans and their immune responses to pathogens and vaccines are highly relevant and, where appropriate models are employed, highly translatable (4-10). An essential element of macaque experiments is the ability to sample tissues in ways and at frequencies that are simply not possible in human patients. This can be done using minimally invasive sampling techniques that provide high quality samples with optimal animal welfare and minimal complications (11,12). Serial sampling of mesenteric lymph nodes (MLN), spleen, and liver have been performed laparoscopically and combined with sampling of peripheral lymph nodes, bone marrow, bronchoalveolar lavage, mucosal samples (GI, vaginal, oral), CSF and blood during a single anesthetic event providing comprehensive information from key sites throughout the body. These samples allow for assessment of immunity, inflammation, and host-pathogen interactions at critical time points such as baseline, pre/post vaccine or intervention, and/or pre/post challenge (13)(14)(15)(16)(17)(18). This sampling can be combined with imaging for targeted sampling to ensure that localized events, such as interactions at local draining lymph nodes, are appropriately captured (19). This sampling can be done even in the face of significant immunosuppression, such as is necessary to perform hematopoietic stem cell transplant and modeling HIV reservoir elimination/ functional cure similar to what has occurred in a handful of human patients. The results of this model have provided critical insights demonstrating that the last place intact Simian Immunodeficiency Virus (SIV) can be detected in macaques that go on to be functionally cured is the MLN. The model further demonstrated that once intact SIV is no longer detected at this site the animals remain aviremic upon antiretroviral therapy (ART) cessation; an important finding that can help guide physicians attempting to achieve the best outcomes for their patients (14). However, the need for indwelling catheters and multiple surgeries combined with immunosuppression for successful allogeneic transplantation can promote the risk of infections that can impact animal welfare and present a risk to occupationally exposed staff. Therefore, assessment of the health status of the animals and ensuring that their background pathogen status going into these critical experiments is optimized for the health of the macaques as well as the safety of occupationally exposed staff is essential. One of the Frontiers in Immunology front...
