Microglia are the resident immune cells of the brain, crucial for the maintenance of the homeostasis in the CNS. When brain homeostasis is perturbed, microglia undergo a process of activation that profoundly change their morphology, to carry out specialized functions by releasing cytokines and chemokines. The morphological changes are driven by massive cytoskeletal modifications, that allow the cells to become from ramified to more ameboid. The role of the actin cytoskeleton in driving these morphological changes, and therefore the specialized functions of activated microglia, has been extensively studied, while the role of the tubulin cytoskeleton have been almost ignored. Microtubules represent a major scaffold in the cell for the transport of macromolecules, organelles, for maintaining the cell shape and for cell movement. Understanding the microtubule structure, organization and modifications that underlie the morphological changes of activated microglia can provide new tools to understand microglia activation process. Microglia activation is a salient feature of neuroinflammation, prominent in many neurodegenerative diseases. Recently, the centrosome - the main microtubule organizing center- dynamics has been correlated with the release of cytokines in activated macrophages. Thus, microtubule cytoskeleton modifications represent a crucial aspect of the morphological changes that are functional to drive specialized and diverse activated microglia functions, and targeting the microtubules can let to the disclosure of new mechanisms to modulate microglia-mediated neuroinflammation.
Here, we aim to describe for the first time the organization of microglia microtubule cytoskeleton, to identify microglia cytoskeletal mechanisms responsible for morphology changes in activated cells, and to target structural elements driving microglia release of inflammatory cytokines.
The novelty of this project reside in the novel insights into the microglia microtubule cytoskeleton, almost ignored so far, useful to disclose new mechanism to modulate activated microglia-triggered neuroinflammation.
The cytoskeleton is a major player in the trafficking of organelles and molecules inside the cell, and can be one of the first target to modulate the release of detrimental substances from the cells. Here, we will structurally and functionally characterized for the first time this cellular compartment in microglia cells. In addition, microtubules organization and dynamics can be specifically targeted and modulated thus offering novel therapeutic strategies in counteract neuroinflammation.
Here, we aim to use murine primary microglia cells for the in vitro part of the project: we aim to optimize the existing culturing condition to maintain microglia at a steady state on order to recapitulate in vitro the homeostatic condition.
We will validate the in vitro results moving to an in vivo model of microglia retinal activation providing a detailed characterization of a previously unknown part of microglia cell biology and trying to overcome the in vitro limitations.
This work will provide extremely valuable basic knowledge and more importantly will lead to the identification of new microglia activation markers and targetable molecules for the development of novel prognostic and therapeutic approaches for the detection and treatment of neuroinflammation.