Neural Plasticity

Review Article

The Role of Autoimmunity in the Pathogenesis of Sudden Sensorineural Hearing Loss

Table 2

The innate immune cells and adaptive immune cells in the inner ear.


Immune cells		Function		Distribution	References

Innate immune cells	Macrophages	Promote the proliferation of T cells and B cells; Process and present antigens and participate in the regulation of adaptive immune responses; Phagocytosis and digestion of pathogenic microorganisms; Mediate and promote inflammatory responses		Endolymphatic sac and subepithelial and endoluminal space and the scala tympani and scala vestibuli.	[37, 38, 87, 88]
	Granulocytes	Anti-inflammatory, release of some inflammatory factors.		In the scala tympani, in the scala vestibuli from the basal turn to the apex, and in the modiolus.	[88–90]

Adaptive immune cells	B cells	Antigen identification and presentation. Activated B cells differentiate into plasma cells that secrete antibodies.		Peripheral circulation system, infiltrating into the endolymph and perilymph of the scala tympani and the scala vestibule and the endolymphatic sac.	[38, 91]
	Helper T cells	Th1 cells	Mediate cellular immunity; Secrete some cytokines, such as IFN-γ.	From the peripheral circulation system, infiltrate into the scala tympani, the scala vestibuli, and the perisaccular connective tissue of the endolymphatic sac and the modiolar vessels.	[20, 21, 52, 54, 82, 87, 91, 92]
		Th2 cells	Mediate humoral immunity; Secrete cytokines IL-4, IL-5, and IL-13.
		Th17 cells	Secrete inflammatory cytokines IL-17 and IL-22; act as inflammation-initiating cells.
	Suppressor T cells	CD4⁺/CD25⁺ Th cells	Negative regulator of immune response; CD4⁺CD25⁺ regulatory T cells play an immunosuppressive function in the periphery; iTregs can secrete the suppressive cytokines IL-10 and TGF-β.	From the circulation, infiltrate into the modiolus, the scala tympani, and the perisaccular connective tissue of the endolymphatic sac.	[55, 87, 92, 93]
		Antigen-specific regulatory T cells (inducible regulatory T cells (iTregs))
	Lymphocytes	Anti-inflammatory		In the scala tympani, in all turns of the cochlea, and in smaller numbers in the scala vestibuli.	[51]