Related Experiment Videos
In-vitro matured human macrophages express Alzheimer's beta A4-amyloid precursor protein indicating synthesis in
Abstract:
Microglia which are consistently associated with Alzheimer's disease (AD) senile plaques are part of the mononuclear phagocyte system. In-vitro matured human monocyte-derived macrophages feature many immunological characteristics of microglia. We found strong constitutive expression of Alzheimer's beta A4-amyloid precursor protein (APP) in human mononuclear phagocytes after terminal in-vitro maturation from monocytes to macrophages. Amyloid has previously been found to be associated with microglia in AD brains, however, it remained unclear whether the material was synthesized in or had been phagocytosed by the cells. The findings presented here support the assumption that brain microglia may contribute to APP synthesis in AD brain.
Insights
Human macrophages, similar to microglia, express Alzheimer's beta A4-amyloid precursor protein (APP). This suggests microglia may synthesize APP in Alzheimer's disease (AD) brains, contributing to amyloid plaques.
Area of Science:
- Neuroscience
- Immunology
- Cell Biology
Background:
- Microglia, key cells in Alzheimer's disease (AD) pathology, are part of the mononuclear phagocyte system.
- Monocyte-derived macrophages in vitro share immunological traits with microglia.
- Amyloid presence in AD brains has been linked to microglia, but its origin (synthesis vs. phagocytosis) was unclear.
Purpose of the Study:
- To investigate the expression of Alzheimer's beta A4-amyloid precursor protein (APP) in human monocyte-derived macrophages.
- To determine if microglia, via their macrophage counterparts, contribute to APP synthesis in the context of Alzheimer's disease.
Main Methods:
- Terminal in-vitro maturation of human monocytes into macrophages.
- Assessment of immunological characteristics of these in-vitro matured macrophages.
- Analysis of Alzheimer's beta A4-amyloid precursor protein (APP) expression in the differentiated macrophages.
Main Results:
- In-vitro matured human monocyte-derived macrophages exhibited strong constitutive expression of Alzheimer's beta A4-amyloid precursor protein (APP).
- These macrophages displayed immunological characteristics similar to microglia.
Conclusions:
- Human mononuclear phagocytes, including in-vitro derived macrophages, express APP.
- These findings support the hypothesis that brain microglia may synthesize APP, contributing to its presence in Alzheimer's disease brains.