ER and SOCE Ca 2+ signals are not required for directed cell migration in human microglia.
Alberto GranzottoAmanda McQuadeJean Paul ChadarevianHayk DavtyanStefano Luca SensiIan ParkerMathew Blurton-JonesIan SmithPublished in: bioRxiv : the preprint server for biology (2024)
The central nervous system (CNS) is constantly surveilled by microglia, highly motile and dynamic cells deputed to act as the first line of immune defense in the brain and spinal cord. Alterations in the homeostasis of the CNS are detected by microglia that respond by migrating toward the affected area. Understanding the mechanisms controlling directed cell migration of microglia is crucial to dissect their responses to neuroinflammation and injury. We used a combination of pharmacological and genetic approaches to explore the involvement of calcium (Ca 2+ ) signaling in the directed migration of induced pluripotent stem cell (iPSC)-derived microglia challenged with a purinergic stimulus. This approach mimics cues originating from injury of the CNS. Unexpectedly, simultaneous imaging of microglia migration and intracellular Ca 2+ changes revealed that this phenomenon does not require Ca 2+ signals generated from the endoplasmic reticulum (ER) and store-operated Ca 2+ entry (SOCE) pathways. Instead, we find evidence that human microglial chemotaxis to purinergic signals is mediated by cyclic AMP in a Ca 2+ -independent manner. These results challenge prevailing notions, with important implications in neurological conditions characterized by perturbation in Ca 2+ homeostasis.
Keyphrases
- cell migration
- inflammatory response
- neuropathic pain
- protein kinase
- endoplasmic reticulum
- spinal cord
- stem cells
- endothelial cells
- blood brain barrier
- lipopolysaccharide induced
- lps induced
- induced pluripotent stem cells
- gene expression
- mass spectrometry
- cerebral ischemia
- copy number
- endoplasmic reticulum stress
- reactive oxygen species
- diabetic rats
- fluorescence imaging