Although the existing humanized mouse model begins to allow establishment of infection models of human pathogens, such as HIV, the current system is far from optimal.
In particular, zebrafish is a useful model for understanding aquatic pathogens such as Staphylococcus aureus [ 39], Pseudomonas aeruginosa [ 40], Mycobacterium marinum [ 41], Streptococcus iniae [ 42], and Edwardsiella tarda [ 33].
Moreover, B. subtilis undergoes a simple differentiation program and is the model to understand many important pathogens such as B. anthracis, Staphylococcus aureus and Listeria monocytogenes.
Furthermore it would be interesting to investigate the role of the Sps system during infection of B. cereus in other host models and also in other human pathogens, such as B. anthracis, Clostridium species and in insect pathogens like B. thuringiensis or in Paenibacillus.
For long-lived pathogens such as tuberculosis, an aggregate model may be appropriate, as infection rates are low and latent periods are long.
Support for these models has been investigated primarily in vector-borne pathogens, such as Borrelia burgdorferi (the causative agent of Lyme disease) and Louping ill virus [6], [8].
More recently, N. benthamiana has also emerged as a popular model for the study of bacterial plant pathogens and filamentous pathogens such as fungi and oomycetes.
In the future, this model could be extended to the study of more traditional respiratory pathogens such as mycobacteria and dimorphic fungi.
They employ a wide variety of study systems, including bacteria-bacteriophage studies, and tissue culture experiments using molecular virology models such as vesicular stomatitis virus and Sindbis virus, and disease pathogens such as dengue virus.
In the murine model, induction of Th1/Th17 cells by CX3CR1+ DCs initiates the host defence against intestinal pathogens, such as Salmonella [40].
