Nanotopographical cues for regulation of macrophages and osteoclasts: emerging opportunities for osseointegration

Table 2 Representative studies illustrating how size effect of nanotubes affect macrophage polarization

Diameter of nanotubes	Cells/Animals	M1 markers	M2 markers	Overall polarization	References
30 and 80 nm	Human monocyte-derived macrophages and human BMSCs Sprague Dawley rats	↓CD86, CCR7 ↓IL-1β, IL-6	↑CD206, CD163 ↑IL-10 ↑TGF-β, Arg1	M2 on 30 nm	[117], [18]
30 and 80 nm		↑CD86, CCR7 ↑IL-1β, IL-6, IFN-γ ↑iNOS	N/A	M1 on 80 nm	[117], [18]
30 and 80 nm	J774A.1	↓TNF-α ↓MCP-1, MIP-1α (especially on 80 nm)	N/A	M2 (especially on 80 nm)	[119]
20, 50 and 120 nm	RAW 264.7	↓TNF-α ↓MCP-1, MIP-1a	N/A	M2-like (especially 50 and 120 nm)	[120]
About 80 nm	RAW 264.7	↓IL-6, IL-1β ↓TNF-α ↓MCP-1, MIP-1α, RANTES ↓NO	N/A	M2-like	[116], [121]
About 50–140 nm	THP1 and HUVECs	↓CD86, CCR7 ↓IL-1β, IL-8 ↓TNF-α, iNOS	↑CD206 ↑IL-10 ↑Arg1, VEGF	M2	[122], [123]
30, 70 and 110 nm	RAW 264.7 and rat BMSCs	↑CCR7 (70 and 110 nm) ↑IL-1β, IL-6, IL-8 (70 and 110 nm) ↑TNF-α (110 nm) ↑NO (110 nm)	↓TGF-β1	M1 on 110 nm under oxidative stress	[124]
30, 70 and 120 nm	RAW 264.7	N/A	↑BMP2 ↓TGF-β1 (30 nm) ↑ICAM-1 (30 and 70 nm)	Not clearly defined	[128]

ISSN: 1477-3155