Laser-induced heating modulates microglial calcium signaling

Infrared neural modulation is an optical technique to stimulate or inhibit neural activity with pulsed infrared light (IR). This study focuses on effects of IR and heat on microglial calcium signaling, a main indicator of physiological changes within the immune-like cell. Widefield fluorescence microscopy quantified the intracellular calcium fluxes, cell death, and early apoptosis fluorescent indicators in BV2 immortalized microglia cell culture after irradiation. We have found that unique cellular responses are highly associated with different temperature increases, and the irradiance thresholds for these responses do not drive cells to Caspase-3 apoptosis nor necrotic cellular death.