Table 3.

Gene expression of selected extracellular matrix components in 3D lung microtissues using qRT-PCR

ECM Protein Mean Fold Change ± SD	Carbon Black	Carbon Nanotubes	Asbestos
COL1A1	1.12 ± 0.23	3.64 ± 0.82	2.12 ± 0.51
	p = 0.981	p = 0.005	p = 0.062
COL3A1	1.33 ± 0.15	6.33 ± 0.65	2.57 ± 0.25
	p = 0.555	p < 0.001	p = 0.002
Decorin	0.97 ± 0.04	10.97 ± 1.58	3.53 ± 1.69
	p = 0.999	p < 0.001	p = 0.065

Microtissues were exposed to 10 μg/mL of each test nanomaterial for 4 days. qRT-PCR was used to confirm the relative gene expression changes detected in the PCR arrays (Fig. 4). Mean fold changes in gene expression were calculated relative to untreated microtissues based on 3 independent experiments. A p-value < 0.05 is considered statistically significant.