Table 2.

Studies on the role of different immune cells in TBI.

Authors	Immunocyte	Role	The research methods	References
Roth et al.	Microglia, astrocytes	The skull is permeable to small molecular weight compounds and uses this delivery route to modulate inflammation and therapeutically ameliorate brain injury through transcranial administration of the ROS scavor glutathione	Traumatic Head Injury Neuroimaging Classification (THINC)	(133)
Davalos et al.	Microglia	ATP is an important signaling molecule that mediates interactions between various cell types in the brain, and glial and endothelial cells may contribute to microglial responses by releasing large amounts of ATP upon injury	Microglia were imaged in vivo using a two-photon microscope	(137)
Liu et al.	Microglia, astrocytes	The innate immune system engages in a series of PRRS to detect “danger” signals, such as PAMPs or DAMPs, to defend against infection or injury. NLR recognizes many PAMPs as well as various DAMPs to activate the assembly of inflammasomes that trigger the maturation of proinflammatory cytokines, such as IL-1β and IL-18	Western blot analysis	(139)
Liu et al.	Neutrophils	Neutrophils are an important component of the innate immune system, and their inappropriate or excessive activation may lead to tissue damage.	Drug blockade, etc.	(147)
Damani et al.	Microglia	Most microglia are long-lived cells that have a long residence time in the CNS and are therefore susceptible to the in situ aging effects that occur during the normal lifespan of the animal	In vitro imaging of the explant retina	(149)
Doering et al.	Zinc-rich (ZEN) neurons	Zn ions are protective against TBI effects	Diseased mice were treated with DEDTC or selenite	(150)
Loane et al.	Microglia	In injured brains, microglia produce neuroprotective factors that remove cellular debris and coordinate the process of nerve repair	Drug therapy, gene blocking, etc	(142)
Griffin et al.	Microglia-directed neurons	Traumatic brain injury, mild and severe, open and closed, leads to immune suppression and infection	Autologous reinfusion of WBCs (adoptive immune therapy)	(132)
Jassam et al.	Microglia, astrocytes	TBI induces an immune response composed of locally and peripherally derived participants that begins within minutes of the onset of TBI if the injury does not resolve or causes chronic diseases such as chronic traumatic encephalopathy	Inhibitors block immune cell activation	(44)
Edwards et al.	Steroids	Refutes any substantial reduction in corticosteroid mortality or severe disability within 6 months after traumatic brain injury	MRC CRASH: A randomized controlled trial of the effects of corticosteroids	(141)

TBI, Traumatic brain injury.