Plaque assay for human coronavirus NL63 using human colon carcinoma cells

Table 1 Comparison of hCoV-NL63 replication by real time RT-PCR using different cell cultures

Designation*	Day 0 [copies/μL]	Day 7 [copies/μL]	Amplification factor	Cytopathogenic effect (CPE)
Vero E6	6.94e3	3.05e7	4.39e3	None
Vero FM	1.78e4	4.51e9	2.54e5	None
CaCo-2	3.55e3	1.25e10	3.54e6	round and detached, dead cells with cell debris in supernatant, strong effect
Calu1	2.61e4	5.33e6	2.04e2	None
Calu6	7.95e3	5.00e5	6.29e1	None
POEK	8.11e4	3.03e5	3.74e0	None
PK13	2.66e2	7.78e5	2.93e3	None
293lp	3.67e3	3.09e7	8.42e3	None
FeA	1.45e4	5.83e5	4.03e1	None
RD	3.14e5	1.57e4	4.99e-2	None
PS	1.20e4	1.44e6	1.19e2	None
LLC-MK2	4.00e3	2.65e6	6.62e2	round and detached, weak effect

* Vero E6 rhesus kidney cells (ATCC CRL-1586), Vero FM rhesus kidney cells (ATCC CCL-81), CaCo-2 human colon carcinoma (ATCC HTB-37), Calu 1 human lung carcinoma (ICLC HTL95002), Calu 6 human lung carcinoma (ICLC HTL97003), POEK porcine foetal kidney (cell culture collection of the Robert Koch-Institute (RKI), Berlin, Germany), PK13 porcine kidney (cell culture collection of the Bernhard-Nocht-Institute (BNI), Hamburg, Germany), 293 human embryonic kidney (ATCC CRL-1573), FEA feline embryonic fibroblast (kindly provided by Dr. Marcel Asper, NewLab Inc., Cologne), RD human rhabdomyosarcoma cells (RKI), PS porcine kidney cells (RKI), and LLC-MK2 African green monkey kidney cells (ATTC CCL-7, kindly provided by Lia van der Hoek, Academic Medical Center Amsterdam, The Netherlands).

ISSN: 1743-422X