TY - JOUR
T1 - Cholesterol-depleted cells that are relatively permissive for Semliki Forest virus infection
AU - Marquardt, Marianne T.
AU - Kielian, Margaret
N1 - Funding Information:
We thank Matthew Klimjack for experimental assistance and Jae Ryu for advice on the fusion/infection assay. We are grateful to Malini Vashishtha, Duncan Wilson, and Pamela Stanley for critical reading of the manuscript. This work was supported by grants to M.K. from the American Cancer Society (VM-41) and the Hirschl Charitable Trust, and by Cancer Center Core Support Grant NIH/NCI P30-CA13330. M.T.M. was supported by NIH training Grant 2T32 CA09173-15 and by funds from the Albert Einstein College of Medicine. Data in this paper are from a thesis submitted in partial fulfillment of the requirements for the Degree of Doctor of Philosophy in the Sue Golding Graduate Division of Medical Sciences, Albert Einstein College of Medicine, Yeshiva University.
PY - 1996/10/1
Y1 - 1996/10/1
N2 - Semliki Forest virus (SFV), an enveloped alphavirus, infects cells by endocytosis followed by low pH-triggered fusion of the virus and endocytic vesicle membranes. Progeny virus is released by budding from the cell plasma membrane. In vitro SFV fusion with artificial liposomes is triggered by low pH and is dependent on the presence of cholesterol and sphingolipid in the target liposome membrane. In tissue culture, both SFV fusion and virus exit are strongly cholesterol-dependent when assayed in cholesterol-depleted insect cells. We here describe the preparation of insect cells that while not containing detectable amounts of cholesterol, have adapted to sterol-depleted conditions, resulting in a more permissive phenotype for SFV infection. Although still less efficient at supporting SFV infection than control cholesterol-containing cells, the adapted cells show a 45-fold increase in primary infection by SFV, increased release of progeny virus, and enhanced virus growth kinetics compared to nonadapted cholesterol-depleted cells. The adapted cells are also about 35-fold more permissive for low pH-induced fusion of SFV with the plasma membrane, suggesting that adaptation correlates with a change in the cell membrane.
AB - Semliki Forest virus (SFV), an enveloped alphavirus, infects cells by endocytosis followed by low pH-triggered fusion of the virus and endocytic vesicle membranes. Progeny virus is released by budding from the cell plasma membrane. In vitro SFV fusion with artificial liposomes is triggered by low pH and is dependent on the presence of cholesterol and sphingolipid in the target liposome membrane. In tissue culture, both SFV fusion and virus exit are strongly cholesterol-dependent when assayed in cholesterol-depleted insect cells. We here describe the preparation of insect cells that while not containing detectable amounts of cholesterol, have adapted to sterol-depleted conditions, resulting in a more permissive phenotype for SFV infection. Although still less efficient at supporting SFV infection than control cholesterol-containing cells, the adapted cells show a 45-fold increase in primary infection by SFV, increased release of progeny virus, and enhanced virus growth kinetics compared to nonadapted cholesterol-depleted cells. The adapted cells are also about 35-fold more permissive for low pH-induced fusion of SFV with the plasma membrane, suggesting that adaptation correlates with a change in the cell membrane.
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U2 - 10.1006/viro.1996.0521
DO - 10.1006/viro.1996.0521
M3 - Article
C2 - 8862414
AN - SCOPUS:0030273051
SN - 0042-6822
VL - 224
SP - 198
EP - 205
JO - Virology
JF - Virology
IS - 1
ER -