Current and Emerging Evidence for Toll-Like Receptor Activation in Sjögren’s Syndrome

Table 3

Systemic TLR dysregulation in human SS.

Cell type	TLR	Results	Refs
PBMCs	2	(i) PBMCs from pSS patients are more responsive to TLR2, TLR4, and TLR6 agonists than those from healthy controls; (ii) TLR2, TLR4, and TLR6 agonists show additive effect in induction of IL-23 and IL-17 secretion in cultured PBMCs from pSS patients	[49]
PBMCs	5	(i) Reduced protein expression	[63]
PBMCs	7	(i) Increased gene expression	[78]
PBMCs	7	(i) Increased protein expression	[63]
B cells	7	(i) Stimulation with TLR7 agonist (CL264) causes elevated IFNα secretion	[80]
CD14+ monocytes	7	(i) Increased expression of TLR7 in pSS patients with a positive type I IFN signature	[77]
PBMCs	8	(i) Elevated gene expression	[63]
moDCs	7/8	(i) Increased maturation in moDCs derived from pSS patients following stimulation with TLR7/8 agonist (CL097)	[82]
B cells	7, 9	(i) Stimulation of naïve B cells from pSS patients with TLR7 (imiquimod) or TLR9 (CpG) agonists causes increased plasma cell differentiation and class switching compared to controls	[81]
CD14+ monocytes	9	(i) Decreased TLR9 expression in monocytes from both type I IFN-positive and IFN-negative pSS patients	[77]
PBMCs	9	(i) Decreased gene expression	[63]
PBMCs	9	(i) Increased gene expression	[78]
PBMCs	9	(i) Enhanced secretion of IL-8, IL-15, IL-1RA, MCP-1, and IL-2R upon stimulation with TLR9 agonist CpG; (ii) TLR9 agonist (CpG) decreased CD80 and CD25 expression	[80]