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Published on: March 21, 2017
Production of a p65fl/fl/LysMCre mouse model with dysfunctional NF-κB signaling in bone marrow-derived macrophages
Ahmet K Korkaya1, Jeffrey Fischer1, Anthony Peppers1
1Department of Biological Sciences, Augusta University, Augusta, Georgia, USA.
Abstract:
Here, we describe the production and characterization of a novel p65fl/fl/LysMCre mouse model, which lacks canonical nuclear factor-kappaB member RelA/p65 (indicated as p65 hereafter) in bone marrow-derived macrophages. Cultured bone marrow-derived macrophages that lack p65 protein reveal NF-κB signaling deficiencies, a reduction in phagocytic ability, and reduced ability to produce nitrites. Despite abnormal bone marrow-derived macrophage function, p65fl/fl/LysMCre mice do not exhibit differences in naïve systemic immune profiles or colony forming units and time to death following Salmonella infection as compared to controls. Additionally, p65fl/fl/LysMCre mice, especially females, display splenomegaly, but no other obvious physical or behavioral differences as compared to control animals. As bone marrow-derived macrophages from this transgenic model are almost completely devoid of canonical nuclear factor-kappaB pathway member p65, this model has the potential for being very useful in investigating bone marrow-derived macrophage NF-kappaB signaling in diverse biological and biomedical studies.
Insights
Researchers developed a new mouse model lacking the p65 protein in macrophages, revealing immune signaling defects but no significant changes in infection outcomes or overall health.
Area of Science:
- Immunology
- Molecular Biology
- Genetics
Background:
- Nuclear factor-kappaB (NF-κB) signaling is crucial for immune responses.
- The canonical NF-κB pathway member RelA/p65 plays a key role in macrophage function.
- Understanding p65's specific role in macrophages requires targeted genetic models.
Purpose of the Study:
- To generate and characterize a novel mouse model lacking p65 in bone marrow-derived macrophages.
- To investigate the functional consequences of p65 deficiency in macrophages.
- To assess the utility of this model for studying NF-κB signaling in macrophages.
Main Methods:
- Generation of p65fl/fl/LysMCre mice.
- Culture and characterization of bone marrow-derived macrophages (BMDMs).
- Assessment of NF-κB signaling, phagocytic ability, nitrite production, systemic immune profiles, and Salmonella infection outcomes.
Main Results:
- p65-deficient BMDMs exhibited NF-κB signaling deficiencies, reduced phagocytosis, and impaired nitrite production.
- p65fl/fl/LysMCre mice showed no significant differences in immune profiles or survival after Salmonella infection compared to controls.
- Splenomegaly was observed in p65fl/fl/LysMCre mice, particularly females, without other apparent physical or behavioral changes.
Conclusions:
- The p65fl/fl/LysMCre mouse model effectively lacks canonical NF-κB member p65 in macrophages.
- This model demonstrates the critical role of p65 in macrophage function, independent of systemic infection outcomes.
- This valuable tool can advance research into macrophage NF-κB signaling in various biological contexts.
