Activation and function of murine primary microglia in the absence of the prion protein

- We evaluated the role of prion protein in mouse primary microglia.
- There were no differences in the activation and function of cells regardless PrPC expression.
- We suggest a cautionary approach when testing PrPC actions in cell lines alone.

The prion protein (PrPC) is predominantly expressed in the nervous and immune systems and is involved in relevant cell signaling. Microglia participate in neuroimmune interactions, and their regulatory mechanisms are critical for both health and disease. Despite recent reports with a microglial cell line, little is known about the relevance of PrPC in brain microglia. We investigated the role of PrPC in mouse primary microglia, and found no differences between wild type and Prnp-null cells in cell morphology or the expression of a microglial marker. Translocation of NF-κB to the nucleus also did not differ, nor did cytokine production. The levels of iNOS were also similar and, finally, microglia of either genotype showed no differences in either rates of phagocytosis or migration, even following activation. Thus, functional roles of PrPC in primary microglial cells are - if present - much more subtle than in transformed microglial cell lines.

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