Table 1 T-cell subsets involved in disease pathogenesis of AAV.

CD4⁺CD25⁺

Consists of two functionally different subsets: activated effector T cells (intermediate CD25 expression) and Tregs (high CD25 expression)

CD4⁺CD25⁺ T cells are expanded.

Marinaki et al. [11]

Popa et al. [4]

CD4⁺CD25^highFoxP3⁺CD127^low

Naturally occurring Tregs, potent suppressors, and proliferation and cytokine production of effector T cells

Defect in function reported, but different Treg definition was used (CD25^highFoxP3⁺).

Abdulahad et al. [15]

CD4⁺CD45RO⁺CCR7^-

Effector memory T cells migrate to peripheral tissues but not to lymphatic tissue.

Expanded, decrease during active state of disease

Abdulahad et al. [13]

CD4⁺CD25⁺CD134⁺/GITR⁺

Specific T-cell subset, mainly of effector memory T-cell type

Increased in AAV, association with disease activity and inflammation

Wilde et al. [12]

CD28^nullNKGD2⁺Perforin⁺

Senescent T cells, IFNγ, and TNFα producers; cytotoxic properties

Expanded, abundantly present in granulomas

Lamprecht et al. [28]

CD4⁺CD45RC^low

Produces type 2 cytokines as well as IL-10 and IL-17

Increased in AAV

Ordonez et al. [59]

CD4⁺CCR5⁺IFNγ⁺

IFNγ cells are, by definition, Th1 cells and enhance cellular immune responses.

Skewing toward Th1 in localized WG

Csernok et al. [49]

CD4⁺CCR3⁺IL-4⁺

By definition, Th2 cells promote humoral immune responses.

Skewing toward Th2 in CSS and systemic WG

Kiene et al. [50]

Balding et al. [48]

CD4⁺IL-17⁺

By definition, Th17 cells; IL-17 attracts and activates neutrophils.

Skewing toward Th17 in WG during quiescent disease and in CSS during active disease

Abdulahad et al. [8]

Saito et al. [58]