Transforming growth factor-beta is not the major soluble immunosuppressor in the microenvironments of human breast tumours.
The immunosuppressive nature of the human breast cancer microenvironment was investigated. The soluble fraction of individual tumours was tested for its ability to influence the activation of peripheral blood lymphocytes (PBL) by interleukin-2 (IL-2) and to effect the continued proliferation of cells which had been pre-activated with IL-2. In all cases, both assays were profoundly inhibited (90-100%). None of this inhibition was due to cell killing by the tumour-derived soluble material (TDS). Sixty-two percent of TDS tested contained measurable transforming-growth factor-beta (TGF-beta) activity; following acidification TGF-beta was present in all TDS. However, in neither case was this material present in sufficient amounts to account for the degree of inhibition observed. In addition, neutralisation experiments failed to demonstrate consistent relief of inhibition in the presence of excess anti-TGF-beta antisera. These results demonstrate that TGF-beta s are not the major soluble immunosuppressive materials within human breast tumours.
Xie
J
J
University of Glasgow, St Mungo Department of Surgery, Glasgow Royal Infirmary, U.K.
Gallagher
G
G
D001943:Breast Neoplasms / Q000276:immunology* / Q000473:pathology / Q000601:surgery; D002458:Cell Fractionation; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000302:isolation & purification* / Q000494:pharmacology; D007376:Interleukin-2 / Q000494:pharmacology; D015979:Killer Cells, Lymphokine-Activated / Q000187:drug effects / Q000276:immunology; D007700:Kinetics; D008213:Lymphocyte Activation / Q000187:drug effects*; D008214:Lymphocytes / Q000187:drug effects / Q000276:immunology*; D016212:Transforming Growth Factor beta / Q000302:isolation & purification* / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D007166:Immunosuppressive Agents; D007376:Interleukin-2; D016212:Transforming Growth Factor beta