Abstract
For the controlled production of recombinant proteinsin mammalian cells by transient transfection, it maybe desirable not only to manipulate, but also todiagnose the expression success early. Here, weapplied laser scanning confocal microscopy to monitortransfection induced intracellular Ca2+responses. We compared Chinese hamster ovary (CHO K1)versus human embryo kidney (HEK) 293 cell lines, whichdiffer largely in their transfectability. An improvedcalcium phosphate transfection method was used for itssimplicity and its demonstrated upscale potential.Cytosolic Ca2+ signaling appeared to inverselyreflect the cellular transfection fate. Virtually allCHO cells exhibited asynchronous, cytosolicCa2+ oscillations, which peaked 4 h afteraddition of the transfecting solution. Yet, most ofthe HEK cells displayed a slow and continuousCa2+ increase over the time of transfection. CHOcells, when exposed to a transfection-enhancingglycerol shock, strongly downregulated their Ca2+response, including its oscillations. When treatedwith thapsigargin, a Ca2+ store depleting drug,the number of successfully transfected CHO cells was significantly reduced. Our result points tointracellular store release as a critical componentfor the transfection fate of CHO cells, and its early detection before product visualization.
Keywords: calcium phosphate, CHO-K1, cytosolic calcium signaling, HEK 293, laser scanning confocal microscopy, transient transfection
Full Text
The Full Text of this article is available as a PDF (86.4 KB).
References
- Bading H, Hardingham GE, Johnson CM, Chawla S. Gene regulation by nuclear and cytoplasmic calcium signals. Biochem Biophys Res Commun. 1997;236:541–543. doi: 10.1006/bbrc.1997.7037. [DOI] [PubMed] [Google Scholar]
- Begum N, Leitner W, Reusch JE, Sussman KE, Draznin B. GLUT-4 phosphorylation and its intrinsic activity. Mechanism of Ca(2+)-induced inhibition of insulin-stimulated glucose transport. J Biol Chem. 1993;268:3352–3356. [PubMed] [Google Scholar]
- Berridge MJ. Elementary and global aspects of calcium signalling. J Exp Biol. 1997;200:315–319. doi: 10.1242/jeb.200.2.315. [DOI] [PubMed] [Google Scholar]
- Coco S, Verderio C, De Camilli P, Matteoli M. Calcium dependence of synaptic vesicle recycling before and after synaptogenesis. J Neurochem. 1998;71:1987–1992. doi: 10.1046/j.1471-4159.1998.71051987.x. [DOI] [PubMed] [Google Scholar]
- Dolmetsch RE, Xu K, Lewis RS. Calcium oscillations increase the efficiency and specificity of gene expression. Nature. 1998;392:933–936. doi: 10.1038/31960. [DOI] [PubMed] [Google Scholar]
- Greber UF, Gerace L. Depletion of calcium from the lumen of endoplasmic reticulum reversibly inhibits passive diffusion and signal-mediated transport into the nucleus. J Cell Biol. 1995;128:5–14. doi: 10.1083/jcb.128.1.5. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Greber UF, Suomalainen M, Stidwill RP, Boucke K, Ebersold MW, Helenius A. The role of the nuclear pore complex in adenovirus DNA entry. EMBO J. 1997;16:5998–6007. doi: 10.1093/emboj/16.19.5998. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jordan M, Schallhorn A, Wurm FM. Transfecting mammalian cells: optimization of critical parameters affecting calcium-phosphate precipitate formation. Nucleic Acids Res. 1996;24:596–601. doi: 10.1093/nar/24.4.596. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Loyter A, Scangos GA, Ruddle FH. Mechanisms of DNA uptake by mammalian cells: fate of exogenously added DNA monitored by the use of fluorescent dyes. Proc Natl Acad Sci USA. 1982;79:422–426. doi: 10.1073/pnas.79.2.422. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Orrantia E, Li ZG, Chang PL. Energy dependence of DNA-mediated gene transfer and expression. Somat Cell Mol Genet. 1990;16:305–310. doi: 10.1007/BF01232458. [DOI] [PubMed] [Google Scholar]
- Palfrey HC, Nairn AC. Calcium-dependent regulation of protein synthesis. Adv Second Messenger Phosphoprotein Res. 1995;30:191–223. doi: 10.1016/s1040-7952(05)80008-4. [DOI] [PubMed] [Google Scholar]
- Parekh AB, Penner R. Store depletion and calcium influx. Physiol Rev. 1997;77:901–930. doi: 10.1152/physrev.1997.77.4.901. [DOI] [PubMed] [Google Scholar]
- Perez-Terzic C, Jaconi M, Clapham DE. Nuclear calcium and the regulation of the nuclear pore complex. Bioessays. 1997;19:787–792. doi: 10.1002/bies.950190908. [DOI] [PubMed] [Google Scholar]
- Preuss AK, Pick HM, Wurm F, Vogel H. Transient transfection induces early cytosolic calcium signaling in CHO-K1 cells. In: Ikura K, Nagao M, Masuda S, Sasaki R, editors. Animal Cell Technology: Challenges for the 21st Century. Dordrecht: Kluwer Academic Publishers; 1999. pp. 17–21. [Google Scholar]
- Rosales C, Brown EJ. Signal transduction by neutrophil immunoglobulin G Fc receptors. Dissociation of intracytoplasmic calcium concentration rise from inositol 1,4,5-trisphosphate. J Biol Chem. 1992;267:5265–5271. [PubMed] [Google Scholar]
- Rosen LB, Ginty DD, Greenberg ME. Calcium regulation of gene expression. Adv Second Messenger Phosphoprotein Res. 1995;30:225–253. doi: 10.1016/s1040-7952(05)80009-6. [DOI] [PubMed] [Google Scholar]
- Simonsen CC, McGrogan M. The molecular biology of production cell lines. Biologicals. 1994;22:85–94. doi: 10.1006/biol.1994.1014. [DOI] [PubMed] [Google Scholar]
- Sompayrac LM, Danna KJ. Efficient infection of monkey cells with DNA of simian virus 40. Proc Natl Acad Sci USA. 1981;78:7575–7578. doi: 10.1073/pnas.78.12.7575. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Staedel C, Remy JS, Hua Z, Broker TR, Chow LT, Behr JP. High-efficiency transfection of primary human keratinocytes with positively charged lipopolyamine: DNA complexes. J Invest Dermatol. 1994;102:768–772. doi: 10.1111/1523-1747.ep12377673. [DOI] [PubMed] [Google Scholar]
- Stehno-Bittel L, Perez-Terzic C, Clapham DE. Diffusion across the nuclear envelope inhibited by depletion of the nuclear Ca2+ store. Science. 1995;270:1835–1838. doi: 10.1126/science.270.5243.1835. [DOI] [PubMed] [Google Scholar]
- Wang HX, Ouyang M, Zhang WM, Sheng JZ, Wong TM. Different mechanisms for [Ca2+]i oscillations induced by carbachol and high concentrations of [Ca2+]o in the rat ventricular myocyte. Clin Exp Pharmacol Physiol. 1998;25:257–265. doi: 10.1111/j.1440-1681.1998.t01-18-.x. [DOI] [PubMed] [Google Scholar]
- Wei H, Perry DC. Dantrolene is cytoprotective in two models of neuronal cell death. Neurochem. 1996;67:2390–2398. doi: 10.1046/j.1471-4159.1996.67062390.x. [DOI] [PubMed] [Google Scholar]
- Won JG, Orth DN. Role of inositol trisphosphate-sensitive calcium stores in the regulation of adrenocorticotropin secretion by perifused rat anterior pituitary cells. Endocrinology. 1995;136:5399–5408. doi: 10.1210/endo.136.12.7588288. [DOI] [PubMed] [Google Scholar]