Some latest achievements in immunology research

Liu, Wei

For better understanding human diseases without the added risk of causing harm to an actual human being during the process, modeling diseases on animals is an irreplaceable approach. Zhang et al. [27] reviewed the establishment of a new generation of humanized mice, an animal model for studying HIV-1 immuno-pathogenesis. They propose that the criteria of a robust animal model for "hypothesis-testing/mechanistic" research in human immunology and immuno-pathology should be: (1) it has well studied hemato-lymphoid organs and target cells similar to those of humans; (2) the human pathogens establish infection and lead to relevant diseases; and (3) it is genetically inbred and can be manipulated via genetic, immunological and pharmacological means. Unfortunately, some immunological findings in mice cannot translate directly to the human immune system and many human pathogens infect human cells only. Significant improvements have been achieved recently in humanized mouse models that to some extent overcome these limitations. Three mouse models commonly used in current research of human immune system and HIV-1 diseases are introduced in detail in this article, and novel mechanistic understanding gained from latest studies on HIV-1 infection and pathogenesis using NTB-hu HSC mice is summarized at length as well. Some featured events during clinical latency prior to AIDS developing, such as drop of both CD4 + and CD8 + T cells, depletion of CCR5 + CD4 + memory T cells in the gut-associated lymphoid tissue (GALT), and elevated/reduced level of regulatory T (Treg) cells in infectious diseases and autoimmune diseases respectively, have been able to be scrutinized using appropriate mouse models. In the future, it will be exciting to model directed human tissue-specific differentiation in humanized mice.