Table 3.

Modulation of TLR function by Siglecs adapted from Ref. (95, 155, 156).

Molecules	TLR ligands used	Cell type	Observed phenotype
CD22	TLR3, 4, 7, and 9	B	Enhanced proliferation of CD22 KO B cells
Siglec-G	TLR3, 4, 7, and 9	B	Enhanced proliferation of Siglec-G KO B cells
	HMGB1	DC	Enhanced TNF-α production in Siglec-G KO DCs
Siglec-E	TLR4	Mac	Reduced IL-12 production by cross-linking with Abs
Siglec-H	TLR9	pDC	Reduced IFN-α production by cross-linking with Abs
Siglec-5	TLR2, 3, 4, and 9	Mac	Reduced TNF-α and enhanced IL-10 production by over-expression
Siglec-9	TLR2, 3, 4, and 9	Mac	Reduced TNF-α and enhanced IL-10 production by over-expression
Siglec-11	TLR4	Mac	Reduced IL-1β transcript by cross-linking with Abs
Siglec-14	TLR4	Mac	Augmented TNF-α production by over-expression
CD33/Siglec-3	TLR4/CD14	imDCs	Reduced the phosphorylation of NF-κB
Siglec-9	TLR2	Mac	Siglecs exhibit lectin-dependent changes in cellular localization, which may be partly linked to its control mechanism that increases the production of IL-10