. 2018 Jul 19;19(7):2099. doi: 10.3390/ijms19072099

Table 1.

Described B regulatory (Breg) cell subsets. DC = dendritic cells; NK = natural killer; IL = interleukin; PD-L = program death-ligand; Ig = immunoglobulin; TIM1 = T cell immunoglobulin and mucin domain; TGF = transforming growth factor.

Name	Phenotypic Markers	Function	References
Immature B-cells	CD24^hiCD38^hi	perform their action on CD4 and CD8 T cells, plasmacitoid DCs, and invariant NK T cells by IL-10 secretion, and PD-L1, CD80, CD86, and CD1d ligation	[66,71,72,73,74]
B10 cells	CD24^hiCD27^hi	produce IL-10 and regulate monocytes and effector CD4 T cells	[75]
Granzyme B⁺ (GZMB) cells	CD38⁺CD1d⁺IgM⁺CD147⁺	regulatory function on CD4 T cells by IL10, indoleamine 2,3-dioxygenase (IDO), and GZMB	[76]
Br1	CD25^hiCD71^hiCD73^low	produce IL-10 and allergen-specific IgG4, thus suppressing allergen-specific CD4 cells and maintaining allergen tolerance	[77]
Plasmablasts	CD27^intCD38^hi	produce IL-10, but their target cell type is not known yet	[78]
-	CD39⁺CD73⁺	regulate CD4 and CD8 T cells by adenosine formation, thus reducing inflammation by adenosine triphosphate	[79]
Induced Breg cells	-	produce TGF-ß and IDO to suppress CD4 T cells. These cells are developed after T cell cytotoxic T-lymphocyte antigen 4 interaction	[80]
-	Express TIM1	inhibit CD8 and CD4 T cells by producing IL-10	[81]