title: Effect of cell lysates on retroviral transduction efficiency of cells in suspension culture.
abstract: Recombinant retroviruses are effective vectors able to integrate transgenes into the target cell's genome to achieve longer-term expression. This study investigates the effect of cell lysis products, a common cell culture by-product, on the transduction of suspension cells by gammaretroviral vectors. Cell lysates derived from human and murine suspension cell lines significantly increased the transduction of human TF-1 and K-562 cell lines by gibbon ape leukemia virus-pseudotyped retroviral vectors without altering tropism. The transduction efficiency of TF-1 cells increased as a function of lysate concentration and decreased with increasing target cell concentrations. This was adequately predicted using a saturation equation based on the lysed-to-target cell concentration ratio, R, where: Fold increase = 1+Fold_(Max) (R/(K_(L)+R)). Lysate completely masked the effects of fibronectin when the two were added in combination. With protamine sulfate, the transduction efficiency was increased by lysate to 58% from 20% for protamine sulfate alone. Overall, the presence of cell lysate significantly influenced the outcome of the transduction process, either alone or in the presence of protamine sulfate or fibronectin.
authors.affiliation: Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Pascal R
authors.initials: PR
authors.lastname: Beauchesne
authors.forename: Katherine J
authors.initials: KJ
authors.lastname: Bruce
authors.forename: Bruce D
authors.initials: BD
authors.lastname: Bowen
authors.forename: James M
authors.initials: JM
authors.lastname: Piret
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D018929:Cell Culture Techniques / Q000379:methods*; D002457:Cell Extracts / Q000494:pharmacology*; D045744:Cell Line, Tumor; D002470:Cell Survival; D017077:Culture Media, Conditioned; D004305:Dose-Response Relationship, Drug; D004355:Drug Stability; D005353:Fibronectins; D018014:Gene Transfer Techniques; D005822:Genetic Vectors / Q000235:genetics*; D006801:Humans; D016014:Linear Models; D051379:Mice; D041681:NIH 3T3 Cells; D011479:Protamines; D012190:Retroviridae / Q000235:genetics*; D014170:Transformation, Genetic / Q000187:drug effects*
chemical_list: D002457:Cell Extracts; D017077:Culture Media, Conditioned; D005353:Fibronectins; D011479:Protamines