id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
cord-311773-r9c7sx6r	Gaertner, Diane J.	Susceptibility of rodent cell lines to rat coronaviruses and differential enhancement by trypsin or DEAE-dextran	1991		.txt	text/plain	2675	150	57	Cell lines of rodent origin were tested for susceptibility to infection with rat coronavirus (RCV), including sialodacryoadenitis virus (SDAV) and Parker's rat coronavirus (PRCV). In a single attempt to isolate SDAV-681 from the lung of an experimentally infected rat, syncytia and viral antigen were first seen after 6 passages in untreated L2 (Percy) cells. Based on this finding, a small study was initiated to ascertain the sensitivity of trypsin-treated L2 (Percy) cells for primary isolation of RCVs. Virus isolations were attempted using tissue homogenates previously tested for SDAV-681 by infant mouse inoculation (Table 4 ). Of the cell lines and treatments tested, L2 (Percy) cells treated with trypsin supported maximal growth of RCVs as evidenced by syncytium formation and viral antigen. RCV growth in L2 (Percy) cells was not enhanced by trypsin treatment of later passages when the enzyme was added at the time of virus inoculation.	./cache/cord-311773-r9c7sx6r.txt	./txt/cord-311773-r9c7sx6r.txt