title: Supernatants from lymphocytes stimulated with Bacillus Calmette-Guerin can modify the antigenicity of tumours and stimulate allogeneic T-cell responses.
abstract: BACKGROUND
  Reduced expression of class 1 human leucocyte antigens (HLA1) is often a mechanism by which tumours evade surveillance by the host immune system. This is often associated with an immune function that is unable to mount appropriate responses against disease, which can result in a state that favours carcinogenesis.
  
  
  METHODS
  In the current study, we have explored the effects of Bacillus Calmette-Guerin (BCG) on the cytokine output of leucocytes, which is a key determinant in generating antitumour action, and have also assessed the effect of these cytokine cocktails on HLA1 expression in solid tumour cell lines.
  
  
  RESULTS
  BCG potently activated a broad range of leucocytes, and also enhanced the production of cytokines that were Th(1)-predominant. Supernatants from BCG-treated leucocytes significantly increased the expression of HLA1 on the surface of cancer cell lines, which correlated with increased cytolytic T-cell activity. We also showed that the increased HLA1 expression was associated with activation of intracellular signalling pathways, which was triggered by the increases in the Th(1)-cytokines interferon-γ and tumour necrosis factor-α, as counteracting their effects negated the enhancement.
  
  
  CONCLUSIONS
  These studies reaffirm the role of BCG as a putative immunotherapy through their cytokine-modifying effects on leucocytes and their capacity to enhance tumour visibility.
authors.affiliation: Department of Oncology, Division of Clinical Sciences, St George's, University of London, 2nd floor, Jenner Wing, London SW17 0RE, UK. w.liu@sgul.ac.uk
authors.forename: W M
authors.initials: WM
authors.lastname: Liu
authors.forename: D W
authors.initials: DW
authors.lastname: Fowler
authors.forename: A M
authors.initials: AM
authors.lastname: Gravett
authors.forename: P
authors.initials: P
authors.lastname: Smith
authors.forename: A G
authors.initials: AG
authors.lastname: Dalgleish
mesh_terms: D001500:BCG Vaccine / Q000276:immunology* / Q000494:pharmacology; D017077:Culture Media, Conditioned / Q000378:metabolism / Q000494:pharmacology*; D016207:Cytokines / Q000378:metabolism; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D000939:Epitopes / Q000187:drug effects*; D045325:HCT116 Cells; D015395:Histocompatibility Antigens Class I / Q000378:metabolism; D006801:Humans; D008213:Lymphocyte Activation / Q000502:physiology; D008214:Lymphocytes / Q000276:immunology* / Q000378:metabolism*; D009369:Neoplasms / Q000276:immunology* / Q000473:pathology; D013602:T-Lymphocytes, Cytotoxic / Q000187:drug effects* / Q000276:immunology; D014407:Tumor Cells, Cultured; D015854:Up-Regulation / Q000187:drug effects / Q000276:immunology
chemical_list: D001500:BCG Vaccine; D017077:Culture Media, Conditioned; D016207:Cytokines; D000939:Epitopes; D015395:Histocompatibility Antigens Class I