Project description:Transitory appearance of immune suppressive polymorphonuclear neutrophils (PMN) defined as myeloid-derived suppressor cells (PMN-MDSC) in newborns is important for their protection from inflammation associated with newly established gut microbiota. Here, we report that inhibition of the type I interferon (IFN1) pathway played a major role in regulation of PMN-MDSC suppressive activity during first weeks of life. Expression of the IFN1 receptor IFNAR1 was markedly lower in PMN-MDSC. However, in newborn mice, down-regulation of IFNAR1 was not sufficient to render PMN immune suppressive. That also required the presence of a positive signal from lactoferrin via its receptor LRP2. The latter effect was mediated via NF-kB activation, which was tempered by IFN1 in a manner that involved SOCS3. Thus, we discovered a mechanism of tight regulation of immune suppressive PMN-MDSC in newborns, which may be used in the development of therapies of neonatal pathologies
Project description:In this study, using single cell RNAseq, cell mass-spectrometry, flow cytometry, and functional analysis, we characterized the heterogeneity of polymorphonuclear neutrophils (PMN) in cancer. We described three populations of PMN in tumor-bearing mice: classical PMN, polymorphonuclear myeloid derived suppressor cells (PMN-MDSC), and activated PMN-MDSC with potent immune suppressive activity. In spleens of mice, PMN-MDSC gradually replaced PMN during tumor progression. Activated PMN-MDSC were found only in tumors where they were present at the very early stages of the disease. These populations of PMN in mice could be separated based on the expression of CD14. In peripheral blood of cancer patients, we identified two distinct populations of PMN with characteristics of classical PMN and PMN-MDSC. Gene signature of tumor PMN-MDSC was similar to that in mouse activated PMN-MDSC and was closely associated with negative clinical outcome in cancer patients. Thus, we provided evidence that PMN-MDSC is a distinct population of PMN with unique features and potential for selective targeting opportunities
2021-01-14 | GSE163834 | GEO
Project description:PMN-MDSC elimination enhanced anti-infection capacity and alleviated colonitis
Project description:Polymorphonuclear myeloid-derived suppressor cells (PMN-MDSC) are important regulators of immune responses and promoters of tumor progression in cancer1,2. The heterogeneity of these cells as well as their distinction from neutrophils hampers the progress in understanding of the biology and clinical significance of these cells. PMN-MDSC had a distinct gene signature from neutrophils isolated from the same patients with most prominent changes in genes associated with endoplasmic reticulum (ER) stress response. Surprisingly, low-density lipoprotein (LDL) was one of the most enriched gene regulators and oxidized LDL receptor 1 (OLR1) was one of the most overexpressed genes in PMN-MDSC. Lectin-type oxidized LDL receptor 1 (LOX-1) encoded by OLR1 was expressed in only 0.7% of neutrophils in peripheral blood of healthy donors, whereas 5-15% of neutrophils in cancer patients and 15-50% of neutrophils in tumor tissues were LOX-1+. In contrast to their LOX-1- counterparts, LOX-1+ neutrophils had gene signature, biochemical and functional characteristics of PMN-MDSC. Induction of ER stress in neutrophils from healthy donors up-regulated LOX-1 expression and converted these cells to suppressive PMN-MDSC. Thus, PMN-MDSC have distinct gene signature and LOX-1 can define this population of cells, which may provide new insight to the biology and clinical evaluation of these cells. Examination of LOX1+/LOX1- and PMN/MDSC cells in cancer patient samples
Project description:Polymorphonuclear myeloid derived suppressor cells (PMN-MDSC) are pathologically activated neutrophils that accumulate in cancer and many other pathologic conditions. PMN-MDSC are critically important for the regulation of immune responses in cancer, promotion of tumor progression, and metastases. Despite the recent advances in understanding of the PMN-MDSC biology, the mechanisms responsible for pathological activation of neutrophils are not well defined, which limit selective targeting of PMN-MDSC. Here, we report that mouse and human PMN-MDSC exclusively up-regulate fatty acid transporter protein 2 (FATP2). Over-expression of FATP2 in PMN-MDSC was controlled by GM-CSF, through the activation of STAT5 transcription factor. Genetic ablation of FATP2 abrogated the suppressive activity of PMN-MDSC in spleens and tumors. FATP2 in neutrophils promoted accumulation of oxidized lipids. However, the main mechanism of FATP2 mediated suppressive activity of PMN-MDSC involved uptake of arachidonic acid and synthesis of prostaglandin E2. The selective pharmacological inhibition of FATP2 abrogated activity of PMN-MSC and substantially delayed tumor progression. In combination with check-point inhibitors it blocked tumor progression in mice. Thus, FATP2 mediates acquisition of immune suppressive activity by PMN-MDSC and represents a new target to inhibit the functions of PMN-MDSC and improve the effect of immunotherapy of cancer.
Project description:Analysis of MDSC subsets from naive blood and RMA-S blood and RMA-S tumor, respectively. Tumor-infiltrating MO-MDSCs changed their expression pattern compared to blood and exhibited high levels of chemokines Total RNA obtained from PMN-MDSCs and MO-MDSCs from naive blood or from blood and tumor of RMA-S bearing mice
Project description:Polymorphonuclear myeloid-derived suppressor cell (PMN-MDSC) accumulate in maternal-fetal interface during pregnancy and play a role in maintenance of immune tolerance. Decreased PMN-MDSC is associated with pregnancy complications such as unexplained recurrent pregnancy loss (URPL). Whether PMN-MDSC function is different between normal pregnancy (NP) and URPL remains unexplored. Here we performed whole genome expression profile of 3 decidual PMN-MDSC from normal early pregnancy and 3 decidual PMN-MDSC from URPL. Total RNA were extracted. Cy5-labeled aRNA was hybridized and scanned on a G2505C Agilent Microarray Scanner with Agilent 0.1 XDR software. The gene expression pattern of the PMN-MDSC was significantly different between the NP group and the URPL group.
Project description:The aim of the study is to evaluate whether the preoperative level of myeloid-derived suppressor cells is associated with postoperative complications classified by Clavien-Dindo categories. Levels of all MDSC, polymorphonuclear MDSC (PMNMDSC), monocytic MDSC (MMDSC), early-stage MDSC (EMDSC) and monocytic to polymorphonuclear MDSC ratio (M/PMN MDCS) were established and compared in patients with postoperative complications, severe postoperative complications (>= IIIA according to Clavien-Dindo) and severe septic complications.
Project description:Polymorphonuclear myeloid-derived suppressor cell (PMN-MDSC), also named pathologically activated neutrophil, is a critical component of tumor microenvironment (TME), playing crucial roles in tumor progression and therapy resistance. CD300ld is specifically expressed in normal neutrophils and is upregulated in PMN-MDSCs upon tumor bearing. CD300ld knockout (KO) inhibits the development of multiple tumor types in a PMN-MDSC-dependent manner. Here, we compared the transcriptome of PMN-MDSCs from WT mice and CD300ld KO mice.
Project description:Polymorphonuclear myeloid-derived suppressor cells (PMN-MDSC) are important regulators of immune responses and promoters of tumor progression in cancer1,2. The heterogeneity of these cells as well as their distinction from neutrophils hampers the progress in understanding of the biology and clinical significance of these cells. PMN-MDSC had a distinct gene signature from neutrophils isolated from the same patients with most prominent changes in genes associated with endoplasmic reticulum (ER) stress response. Surprisingly, low-density lipoprotein (LDL) was one of the most enriched gene regulators and oxidized LDL receptor 1 (OLR1) was one of the most overexpressed genes in PMN-MDSC. Lectin-type oxidized LDL receptor 1 (LOX-1) encoded by OLR1 was expressed in only 0.7% of neutrophils in peripheral blood of healthy donors, whereas 5-15% of neutrophils in cancer patients and 15-50% of neutrophils in tumor tissues were LOX-1+. In contrast to their LOX-1- counterparts, LOX-1+ neutrophils had gene signature, biochemical and functional characteristics of PMN-MDSC. Induction of ER stress in neutrophils from healthy donors up-regulated LOX-1 expression and converted these cells to suppressive PMN-MDSC. Thus, PMN-MDSC have distinct gene signature and LOX-1 can define this population of cells, which may provide new insight to the biology and clinical evaluation of these cells.