title: CD11b+/Gr-1+ immature myeloid cells mediate suppression of T cells in mice bearing tumors of IL-1beta-secreting cells.
abstract: Tumor cells secreting IL-1beta are invasive and metastatic, more than the parental line or control mock-transfected cells, and concomitantly induce in mice general immune suppression of T cell responses. Suppression strongly correlates with accumulation in the peripheral blood and spleen of CD11b+/Gr-1+ immature myeloid cells and hematological alterations, such as splenomegaly, leukocytosis, and anemia. Resection of large tumors of IL-1beta-secreting cells restored immune reactivity and hematological alterations within 7-10 days. Treatment of tumor-bearing mice with the physiological inhibitor of IL-1, the IL-1R antagonist, reduced tumor growth and attenuated the hematological alterations. Depletion of CD11b+/Gr-1+ immature myeloid cells from splenocytes of tumor-bearing mice abrogated suppression. Despite tumor-mediated suppression, resection of large tumors of IL-1beta-secreting cells, followed by a challenge with the wild-type parental cells, induced resistance in mice; protection was not observed in mice bearing tumors of mock-transfected fibrosarcoma cells. Altogether, we show in this study that tumor-derived IL-1beta, in addition to its proinflammatory effects on tumor invasiveness, induces in the host hematological alterations and tumor-mediated suppression. Furthermore, the antitumor effectiveness of the IL-1R antagonist was also shown to encompass restoration of hematological alterations, in addition to its favorable effects on tumor invasiveness and angiogenesis that have previously been described by us.
authors.affiliation: Department of Microbiology and Immunology and Faculty of Health Sciences and The Cancer Research Center, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Song
authors.forename: Yakov
authors.initials: Y
authors.lastname: Krelin
authors.forename: Tatyana
authors.initials: T
authors.lastname: Dvorkin
authors.forename: Olle
authors.initials: O
authors.lastname: Bjorkdahl
authors.forename: Shraga
authors.initials: S
authors.lastname: Segal
authors.forename: Charles A
authors.initials: CA
authors.lastname: Dinarello
authors.forename: Elena
authors.initials: E
authors.lastname: Voronov
authors.forename: Ron N
authors.initials: RN
authors.lastname: Apte
mesh_terms: D000818:Animals; D039481:CD11b Antigen; D018920:Coculture Techniques; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D051379:Mice; D022423:Myeloid Cells / Q000276:immunology*; D009361:Neoplasm Invasiveness / Q000276:immunology / Q000517:prevention & control; D009374:Neoplasms, Experimental / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D009389:Neovascularization, Pathologic / Q000188:drug therapy; D019707:Receptors, Chemokine; D017472:Receptors, Interleukin-1 / Q000037:antagonists & inhibitors; D012795:Sialoglycoproteins / Q000008:administration & dosage / Q000494:pharmacology; D013154:Spleen / Q000166:cytology; D013601:T-Lymphocytes / Q000276:immunology*; D047368:Tumor Burden / Q000187:drug effects
chemical_list: D039481:CD11b Antigen; C503133:Gr-1 protein, mouse; C507764:Il1rn protein, mouse; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1; D019707:Receptors, Chemokine; D017472:Receptors, Interleukin-1; D012795:Sialoglycoproteins