Humanized Mice to Study Human T Cell Development

The development and improvement of immunodeficient mice and humanized immune system mouse models

Animal models play an indispensable role in the study of human diseases. However, animal models of different diseases do not fully mimic the complex internal environment of humans. Immunodeficient mice are deficient in certain genes and do not express these or show reduced expression in some of their cells, facilitating the establishment of humanized mice and simulation of the human environment in vivo. Here, we summarize the developments in immunodeficient mice, from the initial nude mice lacking T lymphocytes to NOD/SCID rg^null mice lacking T, B, and NK cell populations. We describe existing humanized immune system mouse models based on immunodeficient mice in which human cells or tissues have been transplanted to establish a human immune system, including humanized-peripheral blood mononuclear cells (Hu-PBMCs), humanized hematopoietic stem cells (Hu-HSCs), and humanized bone marrow, liver, thymus (Hu-BLT) mouse models. The different methods for their development involve varying levels of complexity and humanization. Humanized mice are widely used in the study of various diseases to provide a transitional stage for clinical research. However, several challenges persist, including improving the efficiency of reconstructing the human B cell immune response, extending lifespan, improving the survival rate of mice to extend the observation period, and improving the development of standardized commercialized models and as well as their use. Overall, there are many opportunities and challenges in the development of humanized immune system mouse models which can provide novel strategies for understanding the mechanisms and treatments of human disease.

Overview of Innovative Mouse Models for Imaging Neuroinflammation

Neuroinflammation demands a comprehensive appraisal in situ to gain in-depth knowledge on the roles of particular cells and molecules and their potential roles in therapy. Because of the lack of appropriate tools, direct visualization of cells has been poorly investigated up to the present. In this context, reporter mice expressing cell-specific fluorescent proteins, combined with multiphoton microscopy, provide a window into cellular processes in living animals. In addition, the ability to collect multiple fluorescent colors from the same sample makes in vivo microscopy uniquely useful for characterizing many parameters from the same area, supporting powerful correlative analyses. Here, we present an overview of the advantages and limitations of this approach, with the purpose of providing insight into the neuroinflammation field. We also provide a review of existing fluorescent mouse models and describe how these models have been used in studies of neuroinflammation. Finally, the potential for developing advanced genetic tools and imaging resources is discussed. © 2016 by John Wiley & Sons, Inc.