id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
cord-255181-du6rqc6i	Louz, Derrick	Cross‐species transfer of viruses: implications for the use of viral vectors in biomedical research, gene therapy and as live‐virus vaccines	2005-06-29		.txt	text/plain	8017	425	42	This review addresses a number of potential risk factors and their implications for activities with viral vectors from the perspective of cross‐species transfer of viruses in nature, with emphasis on the occurrence of host‐range mutants resulting from either cell culture or tropism engineering. The HIV virus and contemporary human influenza viruses are prominent examples of viruses that have crossed the species barrier and established themselves permanently in the human population without further dependence on the presence of the original animal host reservoir. The emergence of HIV exemplifies how multiple independent cross-species transmissions of simian viruses that are not associated with disease in their natural hosts eventually resulted in the establishment of two types of HIV in the human population. The following examples demonstrate that upon persistent infection and passage in cell culture, cross-species transmissibility may be promoted by selection of virus variants with an altered host range. Adaptation in cell culture may result in changes in receptor specificity and tropism, and leads to the emergence of host-range mutant viruses.	./cache/cord-255181-du6rqc6i.txt	./txt/cord-255181-du6rqc6i.txt