Open AccessEnhanced T Cell Immunity by B7-H4 Downregulation in Nonsmall-Cell Lung Cancer Cell Lines
Author(s) -
Sun Sq,
Jiang Cg,
Yunfeng Lin,
Yinlong Jin,
PL Huang
Publication year - 2012
Publication title -
journal of international medical research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.421
H-Index - 57
eISSN - 1473-2300
pISSN - 0300-0605
DOI - 10.1177/147323001204000211
Subject(s) - jurkat cells , a549 cell , small hairpin rna , transfection , cell growth , cell cycle , cancer research , t cell , downregulation and upregulation , cell , microbiology and biotechnology , cell culture , gene silencing , biology , immune system , medicine , immunology , gene , biochemistry , genetics , gene knockdown
OBJECTIVES: T cell immunity plays a critical role in host immune surveillance of tumour cell growth and metastatic spread. This study used small hairpin (sh)RNA-mediated gene silencing to target VTCN1 (B7-H4) expression in a nonsmall-cell lung cancer (NSCLC) cell line (A549) and evaluated the effects on T cell immune activity using an in vitro coculture system. METHODS: VTCN1-specific shRNA-expressing plasmid was transfected into A549 cells. Mock transfected and empty plasmid-transfected A549 cells served as controls. VTCN1 expression in A549 cells was determined by reverse transcription– polymerase chain reaction (RT—PCR) for VTCN1 mRNA and Western blotting for B7-H4 protein. Transfected A549 cells were cocultured with Jurkat cells. Jurkat cells were examined for proliferation, apoptosis, cell cycle distribution and intracellular cytokine mRNA and protein levels. RESULTS: VTCN1-specific shRNA efficiently knocked down VTCN1 mRNA and B7-H4 protein levels in A549 cells. This downregulation led to enhanced Jurkat cell proliferation, decreased apoptosis, stimulated cell cycle progression and elevated production of interferon-γ, interleukin (IL)-10 and IL-2. CONCLUSIONS: B7-H4 negatively regulates T cell-mediated antitumour immunity in NSCLC.