title: Vaccine of engineered tumor cells secreting stromal cell-derived factor-1 induces T-cell dependent antitumor responses.
abstract: The CXC chemokine SDF-1 has been characterized as a T-cell chemoattractant both in vitro and in vivo. To determine whether SDF-1 expression within tumors can influence tumor growth, we transfected an expression vector pCI-SDF-1 for SDF-1 into J558 myeloma cells and tested their ability to form tumors in BALB/c. Production of biologically active SDF-1 (1.2 ng/mL) was detected in the culture supernatants of cells transfected with the expression vector pCI-SDF-1. J558 cells gave rise to a 100% tumor incidence, whereas SDF-1-expressing J558/SDF-1 tumors invariably regressed in BALB/c mice and became infiltrated with CD4(+) and CD8(+) T cells. Regression of the J558/SDF-1 tumors was dependent on both CD4(+) and CD8(+) T-cells. Our data also indicate that TIT cells containing both CD4(+) and CD8(+) T-cells within J558/SDF-1 tumors express the SDF-1 receptor CXCR4, and that SDF-1 specifically chemoattracts these cells in vitro. Furthermore, immunization of mice with engineered J558/SDF-1 cells elicited the most potent protective immunity against 0.5 x 10(6) cells J558 tumor challenge in vivo, compared to immunization with the J558 alone, and this antitumor immunity mediated by J558/SDF-1 tumor cell vaccination in vivo appeared to be dependent on CD8(+) CTL. Thus, SDF-1 has natural adjuvant activities that may augment antitumor responses through their effects on T-cells and thereby could be important in gene transfer immunotherapies for some cancers.
authors.affiliation: Research Unit, Saskatchewan Cancer Agency, Department of Oncology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
authors.forename: Meiqing
authors.initials: M
authors.lastname: Shi
authors.forename: Siguo
authors.initials: S
authors.lastname: Hao
authors.forename: Liping
authors.initials: L
authors.lastname: Su
authors.forename: Xueshu
authors.initials: X
authors.lastname: Zhang
authors.forename: Jinying
authors.initials: J
authors.lastname: Yuan
authors.forename: Xuling
authors.initials: X
authors.lastname: Guo
authors.forename: Changyu
authors.initials: C
authors.lastname: Zheng
authors.forename: Jim
authors.initials: J
authors.lastname: Xiang
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000378:metabolism; D019496:Cancer Vaccines; D045744:Cell Line, Tumor; D054377:Chemokine CXCL12; D019743:Chemokines, CXC / Q000378:metabolism*; D002633:Chemotaxis; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D007167:Immunotherapy / Q000379:methods; D051379:Mice; D008807:Mice, Inbred BALB C; D008856:Microscopy, Fluorescence; D009368:Neoplasm Transplantation; D009369:Neoplasms / Q000628:therapy*; D010641:Phenotype; D012313:RNA / Q000737:chemistry; D011994:Recombinant Proteins / Q000737:chemistry; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D014162:Transfection
chemical_list: D000970:Antineoplastic Agents; D019496:Cancer Vaccines; D054377:Chemokine CXCL12; D019743:Chemokines, CXC; C515256:Cxcl12 protein, mouse; D011994:Recombinant Proteins; D012313:RNA