title: Retroviral transduction of human peripheral blood lymphocytes with Bcl-X(L) promotes in vitro lymphocyte survival in pro-apoptotic conditions.
abstract: The prolonged in vivo survival of genetically modified effector cells is crucial to the success of any (gene-modified) adoptive cellular immunotherapy approach. In cancer clinical trials to date, however, the detection of surviving circulating gene-modified T cells has required highly sensitive techniques. In vitro studies of T cell co-stimulation have shown that up-regulation of the anti-apoptosis gene Bcl-X(L) by ligation of CD28 promotes T cell survival, but not proliferation. Here we have investigated the ability to modulate resistance to apoptosis and improve cell survival by transducing human peripheral blood lymphocytes using a retroviral vector that expresses Bcl-X(L). We show that Jurkat cells transduced with Bcl-X(L) retrovirus were partially resistant to Fas (CD95) antibody-induced apoptosis. Subsequent in vitro assays with transduced primary human lymphocytes demonstrates that over-expression of Bcl-X(L) promotes the survival of lymphocytes cultured in the absence of interleukin-2. Activation-induced apoptosis with anti-CD3(epsilon) antibody, OKT3 is also modulated. Furthermore, Bcl-X(L) over-expression in human lymphocytes delays the onset of apoptosis induced by long-term co-culture with tumour cell lines. Despite this improved in vitro survival, in a preliminary experiment to assess safety, no signs of malignancy or autoimmunity were observed in NOD/SCID mice injected with Bcl-X(L) transduced lymphocytes. These results indicate that expression of Bcl-X(L) in lymphocyte therapy either alone or in conjunction with an additional therapeutic gene could enhance persistence of cells in vivo thereby potentially improving the clinical outcome of adoptive cellular therapy.
authors.affiliation: CRC Department of Medical Oncology, Paterson Institute for Cancer Research, University of Manchester, Manchester, UK.
authors.forename: D
authors.initials: D
authors.lastname: Eaton
authors.forename: D E
authors.initials: DE
authors.lastname: Gilham
authors.forename: A
authors.initials: A
authors.lastname: O'Neill
authors.forename: R E
authors.initials: RE
authors.lastname: Hawkins
mesh_terms: D000818:Animals; D017209:Apoptosis; D002470:Cell Survival; D005260:Female; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors / Q000008:administration & dosage; D006801:Humans; D016219:Immunotherapy, Adoptive / Q000379:methods*; D019169:Jurkat Cells; D008214:Lymphocytes / Q000378:metabolism*; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics*; D012190:Retroviridae / Q000235:genetics; D014161:Transduction, Genetic / Q000379:methods*; D051020:bcl-X Protein
chemical_list: C494811:BCL2L1 protein, human; C494812:Bcl2l1 protein, mouse; D019253:Proto-Oncogene Proteins c-bcl-2; D051020:bcl-X Protein