Search results for "Myeloid cells"
showing 6 items of 56 documents
Constant detection of cyclooxygenase 2 in terminal stages of myeloid maturation.
2006
Osteopontin shapes immunosuppression in the metastatic niche.
2014
Abstract The matricellular protein osteopontin (OPN, Spp-1) is widely associated with cancer aggressiveness when produced by tumor cells, but its impact is uncertain when produced by leukocytes in the context of the tumor stroma. In a broad study using Spp1−/− mice along with gene silencing in tumor cells, we obtained evidence of distinct and common activities of OPN when produced by tumor or host cells in a spontaneously metastatic model of breast cancer. Different cellular localization of OPN is associated with its distinct activities, being mainly secreted in tumor cells while intracellular in myeloid cells. OPN produced by tumor cells supported their survival in the blood stream, wherea…
Increased frequencies of CD11b+CD33+CD14+HLA-DRlowmyeloid-derived suppressor cells are an early event in melanoma patients
2014
Myeloid-derived suppressor cells (MDSC) are a heterogeneous cell population characterized by immunosuppressive activity. Elevated levels of MDSC in peripheral blood are found in inflammatory diseases as well as in malignant tumors where they are supposed to be major contributors to mechanisms of tumor-associated tolerance. We investigated the frequency and function of MDSC in peripheral blood of melanoma patients and observed an accumulation of CD11b(+) CD33(+) CD14(+) HLA-DR(low) MDSC in all stages of disease (I-IV), including early stage I patients. Disease progression and enhanced tumor burden did not result in a further increase in frequencies or change in phenotype of MDSC. By investig…
Intrahepatic myeloid-cell aggregates enable local proliferation of CD8+T cells and successful immunotherapy against chronic viral liver infection
2013
Chronic infection is difficult to overcome because of exhaustion or depletion of cytotoxic effector CD8(+) T cells (cytotoxic T lymphoytes (CTLs)). Here we report that signaling via Toll-like receptors (TLRs) induced intrahepatic aggregates of myeloid cells that enabled the population expansion of CTLs (iMATEs: 'intrahepatic myeloid-cell aggregates for T cell population expansion') without causing immunopathology. In the liver, CTL proliferation was restricted to iMATEs that were composed of inflammatory monocyte-derived CD11b(+) cells. Signaling via tumor-necrosis factor (TNF) caused iMATE formation that facilitated costimulation dependent on the receptor OX40 for expansion of the CTL popu…
2015
AbstractTriggering receptor expressed on myeloid cells (TREM)-1 plays an important role in innate immune responses and is upregulated under infectious as well as non-infectious conditions. In addition, a soluble TREM-1 variant (sTREM-1) is detectable in sera or bronchoalveolar-lavage fluids from patients. Currently, various studies are difficult to compare, since the methods of detection by enzyme-linked immunosorbent assays (ELISA) vary among different research groups. In this study, we compared three different s-TREM-1 specific ELISAs and identified individual assay characteristics finding notable differences in sTREM-1 concentrations in part depending on the employed buffers. Investigati…
Role of PRRs (TLR2 and Dectin-1) in hematopoietic stem and progenitor cell differentiation: implications in protection against Candida albicans infec…
2020
Detection of infection by hematopoietic stem and progenitor cells (HSPCs) is essential to replace myeloid cells consumed during the immune response. HSPCs express some functional pattern recognition receptors involved in the recognition of Candida albicans. In this context, our group has previously demonstrated that C. albicans yeasts induce proliferation and differentiation of HSPCs via TLR2 and Dectin-1. In the present PhD thesis, we used in vitro and ex vivo models of HSPC differentiation to investigate the functional consequences for mature myeloid cells of exposure of HSPCs to PAMPs or C. albicans yeasts. In vitro experiments show that murine HSPCs continuously exposed to TLR2 or TLR4 …