23 April, 2017

An exciting new ultra immunodeficient mouse model

By Sheri Wildt

Mouse models are powerful in vivo systems that play an important role in biomedical research. In recent years, there has been growing interest in the use of immunodeficient mice for a wide variety of applications, including immunology, infectious diseases, autoimmunity, and cancer. Mice with compromised immune systems are invaluable tools that not only provide critical insight into genes essential for immune function, but when combined with the transplantation of human cells or tissues, they also have enormous potential to provide scientists with relevant models of human disease.

R2G2 Launch at AACR
Envigo recently launched the R2G2 ultra-immunodeficient mouse at the American Association for Cancer Research (AACR) annual meeting on April 1-5, 2017. A scientific poster on the model demonstrating its advantages over several other commercially available models for oncology research was presented by Sheri Wildt, Global Manager of Genetic Quality and Breeding. The AACR Annual Meeting highlights the best cancer science and medicine from institutions all over the world. Attendees are invited to stretch their boundaries, form collaborations, attend sessions outside their own areas of expertise, and learn how to apply exciting new concepts, tools, and techniques to their own research. This year’s annual meeting attracted over 21,000 participants from 80 countries. Attendees gathered to discuss over 6,000 abstracts and to hear more than 250 invited presentations on significant discoveries in basic, clinical, and translational cancer research. Scientific award lectures, grant writing workshops, networking events, and educational sessions round out this comprehensive program. This year’s meeting was held at the Washington, DC Convention and Conference Center.

R2G2 Scientific Poster
The R2G2 poster presented data from several key characterization studies on the model, including growth curve analysis, a comparative radiosensitivity study, a PDX xenograft study, complete blood counts and chemistry, and comparative flow cytometry data. Many attendees visited the poster and were interested in trying this new model in their own research programs. Of particular interest to investigators was the data demonstrating the model’s reduced radiosensitivity, meaning it has the ability to tolerate the effects of a wider range of radiation dosages. This helps researchers more closely simulate the treatment environments of cancer therapies, where patients receive combinations of chemo/immunotherapy and radiation.

R2G2 Characteristics
The R2G2, a Rag2/IL2RG double knockout model, was created by backcrossing the common gamma chain gene mutation (IL2RG) on to a unique C57BL/6 and 129 mixed background mouse with a mutation in the recombination activating gene 2 (Rag2). The R2G2 mouse addresses common challenges that researchers experience with current models used in oncology, immuno-oncology and infectious disease research.

This new mouse model from Envigo provides distinct advantages over other triple immunodeficient models with the scid mutation. One key benefit that makes it ideal for oncology research is the model’s reduced radiosensitivity, meaning it has the ability to tolerate the effects of a wider range of radiation dosages. This helps researchers more closely simulate the treatment environments of cancer therapies, where patients receive combinations of chemo/immunotherapy and radiation. The model is highly immunodeficient due to the lack of functional T, B, and NK cells resulting from the Rag2 and IL2rg gene disruptions. Moreover, the R2G2 also brings the benefit of reduced “leakiness” when compared to several other models with the scid mutations – whose immune systems regenerate as they age, forming new T cells, which can confound experiments.

To discover more about the radiosensitivity of immunodeficient mouse models in oncology studies, download this whitepaper.

[White paper] Radiosensitivity of immunodeficient mouse models in oncology studies

Category // Research models and services, AACR, Biomedical research