Improved multilineage human hematopoietic reconstitution and function in NSGS mice

Area of Science:

• Immunology
• Hematology
• Transgenic animal models

Background:

• NOD/SCID (NS) mice are widely used for human hematopoietic xenografts.
• Sub-strains of NS mice possess unique characteristics for specific research applications.

Purpose of the Study:

• To compare the engraftment and output of umbilical cord blood (UCB) CD34+ cells in four immune-deficient mouse strains: NS, NSG, NSS, and NSGS.
• To evaluate the functional capacity of the generated human immune system in these models.

Main Methods:

• Genetic manipulation of NOD/SCID mice to create NSG (IL2RG knockout), NSS (cytokine transgenic), and NSGS (IL2RG knockout and cytokine transgenic) strains.
• Engraftment and analysis of human umbilical cord blood (UCB) CD34+ cells in the four mouse strains.
• Assessment of immune cell reconstitution, cytokine levels, and immune response to immunization.

Main Results:

• Overall human hematopoietic cell engraftment was highest in IL2RG knockout strains (NSG and NSGS).
• Myeloid cell output was enhanced in strains with transgenic cytokine expression (NSS and NSGS).
• NSGS mice showed more rapid T cell reconstitution, improved B cell differentiation, increased NK cells, and functional immune responses post-immunization.

Conclusions:

• The NSGS mouse model provides a more functional humanized immune system for xenograft studies.
• Myeloid cells and supportive cytokines are crucial for developing a robust xenograft immune system.
• NSGS mice are superior hosts for secondary engraftment and demonstrate a functional response to antigen exposure.