Tracking the tissue distribution of marker dye following intranasal delivery in mice and chinchillas: a multifactorial analysis of parameters affecting nasal retention

The combined mucosal surface area is vast and represents the primary site of entry of most pathogens to the respiratory, gastrointestinal (GI), and urogenital tracts. It is recognized that vaccines delivered parenterally typically only induce weak mucosal immune responses and that by targeting the mucosal immune system protective antibodies and effector lymphocytes could be induced at the primary site of infection. In the present study, we have evaluated an extensive set of conditions required to ensure maximum retention of intranasally administered substances within the nasal cavity in the chinchilla and murine hosts. We report here that many parameters, such as anæsthesia, position of animal during and post delivery, and dosing schedule, must be optimized in concert with each other and that results from one species cannot be extrapolated directly to another animal model.