Microglial SWELL1 deficiency drives male-specific seizure vulnerability but paradoxical neuroprotection through impaired phagocytosis
Abhijeet S. Barath, Aastha Dheer, Laura Montier, Mekenzie M Peshoff, Emily Dale, Flavia Goche, Thanh Thanh Le Nguyen, Mastura Akter, FangFang Qi, Dimitrios Kleidonas, Lauren Harris, Sarah A. Jewanee, Anthony D. Umpierre, Dale B. Bosco, Koichiro Haruwaka, Rajan Sah, Long-Jun Wu
Abhijeet S. Barath, Aastha Dheer, Laura Montier, Mekenzie M Peshoff, Emily Dale, Flavia Goche, Thanh Thanh Le Nguyen, Mastura Akter, FangFang Qi, Dimitrios Kleidonas, Lauren Harris, Sarah A. Jewanee, Anthony D. Umpierre, Dale B. Bosco, Koichiro Haruwaka, Rajan Sah, Long-Jun Wu
View: Text | PDF
Research Article Immunology Neuroscience

Microglial SWELL1 deficiency drives male-specific seizure vulnerability but paradoxical neuroprotection through impaired phagocytosis

Abstract

The discovery of genes encoding the volume-regulated anion channel (VRAC) has enabled detailed exploration of its cell type–specific roles in the brain. LRRC8A (SWELL1) is the essential VRAC subunit. We observed seizure-induced, subunit-specific changes in microglial VRAC expression and investigated its function using conditional KO (cKO) of LRRC8A in microglia. SWELL1 cKO mice exhibited a male-specific increase in kainate-induced seizure severity, yet showed paradoxical neuroprotection against seizure-associated neuronal loss. Mechanistically, SWELL1 deletion led to a cell-autonomous reduction in microglial density and decreased release of VRAC-permeable neuroactive metabolites, including taurine, GABA, and glutamate in culture. Additionally, impaired phagocytic kinetics and reduced lysosomal biogenesis contributed to the observed neuroprotection. These findings reveal potentially novel roles for microglial VRAC in regulating seizure outcomes and microglia-neuron interactions.

Authors

Abhijeet S. Barath, Aastha Dheer, Laura Montier, Mekenzie M Peshoff, Emily Dale, Flavia Goche, Thanh Thanh Le Nguyen, Mastura Akter, FangFang Qi, Dimitrios Kleidonas, Lauren Harris, Sarah A. Jewanee, Anthony D. Umpierre, Dale B. Bosco, Koichiro Haruwaka, Rajan Sah, Long-Jun Wu

×

Figure 5

Cell-autonomous proliferative and phagocytic deficits in cultured SWELL1 cKO microglia.

Options: View larger image (or click on image) Download as PowerPoint
Cell-autonomous proliferative and phagocytic deficits in cultured SWELL1...
(A) Microglia density at 10 days in vitro after plating purified microglia at equal density (4–6 wells/genotype examined in a single experiment). Scale bar: 100 μm. (B) Quantification of microglia density at 12 days in vitro (statistic: unpaired 2-tailed t test). (C) Experimental design for in vitro phagocytosis assay with opsonized latex beads. (D) Bead phagocytosis assay (4 wells/genotype examined in a single experiment). Scale bar: 100 μm. (E) Quantification of percentage of microglia that were positive for phagocytic inclusions over a 2-hour observation window (n = 4 wells/genotype; statistic: 2-way ANOVA). (F) Quantification of average phagocytic load per microglia expressed as GFP+ area (n = 4 wells/genotype; results averaged per well; statistic: 2-way ANOVA). ****P <0.001.