title: Reduced numbers of IL-7 receptor (CD127) expressing immune cells and IL-7-signaling defects in peripheral blood from patients with breast cancer.
abstract: Interleukin-7-receptor-signaling plays a pivotal role in T-cell development and maintenance of T-cell memory. We studied IL-7Ralpha (CD127) expression in PBMCs obtained from patients with breast cancer and examined IL-7 receptor-mediated downstream effects defined by STAT5 phosphorylation (p-STAT5). Reduced numbers of IL-7Ralpha-positive cells were identified in CD4+ T-cells as well as in a CD8+ T-cell subset defined by CD8alpha/alpha homodimer expression in patients with breast cancer. PBMCs obtained from healthy donors (n = 19) and from patients with breast cancer (n = 19) exhibited constitutive p-STAT5 expression in the range of 0-6.4% in CD4+ T-cells and 0-4% in CD8+ T-cells. Stimulation with recombinant human IL-7 for 15 min increased p-STAT5 expression up to 36-97% in CD4+T-cells and to 26-90% in CD8+T-cells obtained from healthy control donors (n = 19). In contrast, PBMCs obtained from 13/19 patients with breast cancer did not respond to IL-7 as defined by STAT5 phosphorylation, despite expression of IL-7Ralpha on T-lymphocytes. T-cells were further characterized for IL- 2 and IFN-gamma production induced by PMA/Ionomycin. PBMCs from 9/19 patients with breast cancer showed decreased IL-2 and IFN-gamma production combined with IL-7-signaling defects; PBMCs from 4 patients with breast cancer exhibited deficient IL-7-signaling, yet intact cytokine production. Reduced numbers of IL-7Ralpha-positive cells and nonresponsiveness to IL-7, defined by lack of STAT5 phosphorylation, characterizes the immunological profile in T-cells from patients with breast cancer.
authors.affiliation: Microbiology, Tumor and Cell Biology Center, Karolinska Institute, Solna, Sweden.
authors.forename: Nalini Kumar
authors.initials: NK
authors.lastname: Vudattu
authors.forename: Isabelle
authors.initials: I
authors.lastname: Magalhaes
authors.forename: Marcus
authors.initials: M
authors.lastname: Schmidt
authors.forename: Vicki
authors.initials: V
authors.lastname: Seyfert-Margolis
authors.forename: Markus J
authors.initials: MJ
authors.lastname: Maeurer
mesh_terms: D001943:Breast Neoplasms / Q000097:blood* / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D016207:Cytokines / Q000378:metabolism; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D015851:Interleukin-7 / Q000235:genetics / Q000494:pharmacology*; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D010766:Phosphorylation; D020395:Receptors, Interleukin-7 / Q000378:metabolism*; D011994:Recombinant Proteins / Q000494:pharmacology; D050799:STAT5 Transcription Factor / Q000378:metabolism; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism
chemical_list: D016207:Cytokines; D015851:Interleukin-7; D020395:Receptors, Interleukin-7; D011994:Recombinant Proteins; D050799:STAT5 Transcription Factor; C415350:interleukin-7 receptor, alpha chain