Predictive value of in vitro assays depends on the mechanism of toxicity of metal oxide nanoparticles

Table 4 Comparison of in vivo lung inflammation data with in vitro assay data based on any dose even implausibly high ones

	Rat (150 cm ²/rat)	A549		16-HBE		THP-1		Alveolar mac		Differentiated PBMC			Differentiated THP-1 ^a			Combined (A549 + THP-1) ^a	Haemolysis
	granulocytes	cytotox ^b	IL-8	cytotox	IL-8	cytotox	IL-1β	cytotox	IL-1β	cytotox	IL-1β	TNF-α	cytotox	IL-1β	TNF-α	IL-8	% haemolysis
CeO₂	+	-	-	-	+	-	-	+	-	-	-	-	+	+	+	+	+
TiO₂-rutile	-	-	-	-	-	-	+	+	+	-	+	+	+	+	+	+	-
CB	-	-	-	-	+	-	-	-	-	+	+	-	-	+	-	-	-
SiO₂	-	-	-	-	-	-	-	-	-	-	-	-	-	+	-	-	-
NiO	+	-	-	-	-	-	-	+	-	+	+	-	+	-	+	-	+
Co₃O₄	+	-	-	-	-	-	-	+	-	+	-	-	-	+	-	-	+
Cr₂O₃	-	+	-	-	-	+	-	+	-	+	+	-	+	+	+	+	-
ZnO	+	+	+	+	+	-	-	+	-	+	+	+	+	-	-	+	N/A
CuO	+	+	+	+	-	+	-	+	+	+	-	-	+	-	-	+	+
Accuracy		5/9	6/9	6/9	5/9	4/9	3/9	7/9	4/9	6/9	3/9	4/9	6/9	2/9	4/9	5/9	8/8
False positive		1/9	0/9	0/9	1/9	1/9	1/9	2/9	1/9	2/9	3/9	1/9	2/9	4/9	2/9	2/9	0/8
False negative		3/9	3/9	3/9	3/9	4/9	5/9	0/9	4/9	1/9	3/9	4/9	1/9	3/9	3/9	2/9	0/8

^aThe highest dose for CuO NP was 3 cm²/mL.
^bCytotoxicity was measured by lactated dehydrogenase (LDH) or trypan blue exclusion assay.
The statistically significant changes compared to vehicle control were marked as '+’ and no significant changes were noted as '-’.

ISSN: 1743-8977