title: Enhancing Protein Expression in HEK-293 Cells by Lowering Culture Temperature.
abstract: Animal cells and cell lines, such as HEK-293 cells, are commonly cultured at 37°C. These cells are often used to express recombinant proteins. Having a higher expression level or a higher protein yield is generally desirable. As we demonstrate in this study, dropping culture temperature to 33°C, but not lower, 24 hours after transient transfection in HEK-293S cells will give rise to ~1.5-fold higher expression of green fluorescent protein (GFP) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors. By following the time course of the GFP-expressing cells growing at 37°C and 33°C from 24 hours after transfection (including 19 hours recovery at 37°C in the normal growth medium), we found that a mild hypothermia (i.e., 33°C) reduces the growth rate of HEK-293S cells, while increasing cellular productivity of recombinant proteins. As a result, green cells remain undivided in a longer period of time. Not surprisingly, the property of a recombinant protein expressed in the cells grown at 33°C is unaffected, as shown by the use of AMPA receptors. We further demonstrate with the use of PC12 cells that this method may be especially useful when a recombinant protein is difficult to express using a chemical-based, transient transfection method.
authors.affiliation: Department of Chemistry, and Center for Neuroscience Research, University at Albany, SUNY, Albany, New York, 12222, United States of America.
authors.forename: Chi-Yen
authors.initials: CY
authors.lastname: Lin
authors.affiliation: Department of Chemistry, and Center for Neuroscience Research, University at Albany, SUNY, Albany, New York, 12222, United States of America.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Huang
authors.affiliation: Department of Chemistry, and Center for Neuroscience Research, University at Albany, SUNY, Albany, New York, 12222, United States of America.
authors.forename: Wei
authors.initials: W
authors.lastname: Wen
authors.affiliation: Department of Chemistry, and Center for Neuroscience Research, University at Albany, SUNY, Albany, New York, 12222, United States of America.
authors.forename: Andrew
authors.initials: A
authors.lastname: Wu
authors.affiliation: Department of Chemistry, and Center for Neuroscience Research, University at Albany, SUNY, Albany, New York, 12222, United States of America.
authors.forename: Congzhou
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Chemistry, and Center for Neuroscience Research, University at Albany, SUNY, Albany, New York, 12222, United States of America.
authors.forename: Li
authors.initials: L
authors.lastname: Niu
mesh_terms: D000818:Animals; D018929:Cell Culture Techniques / Q000379:methods*; D049109:Cell Proliferation; D049452:Green Fluorescent Proteins / Q000378:metabolism; D057809:HEK293 Cells; D006801:Humans; D016716:PC12 Cells; D018408:Patch-Clamp Techniques; D010957:Plasmids / Q000378:metabolism; D051381:Rats; D018091:Receptors, AMPA / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism*; D013696:Temperature; D013997:Time Factors; D014162:Transfection
chemical_list: D018091:Receptors, AMPA; D011994:Recombinant Proteins; D049452:Green Fluorescent Proteins