scholarly journals Ferumoxytol Attenuates the Function of MDSCs to Ameliorate LPS-Induced Immunosuppression in Sepsis

2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Yujun Xu ◽  
Yaxian Xue ◽  
Xinghan Liu ◽  
Yi Li ◽  
Huaping Liang ◽  
...  

AbstractSepsis-induced immunosuppression is recognized as one of the main features responsible for therapeutic failures. Myeloid-derived suppressor cells (MDSCs), which are mainly characterized by their suppressive properties, have been reported to be expanded in sepsis. Ferumoxytol (FMT), an FDA-approved iron supplement, has been shown to possess immune-modulatory properties in tumors. However, it is unclear whether FMT alters the functions of MDSCs to reduce late-sepsis immunosuppression. Here, we showed an immunomodulatory effect of FMT on MDSCs to ameliorate lipopolysaccharide (LPS)–induced immunosuppression in the late stage of sepsis. Separation of cells with internalized FMT and detection of the intracellular iron content showed that MDSCs could uptake FMT. Low doses of FMT had no effects on the cell viability of MDSCs, but FMT inhibited the expansion of MDSCs in vitro. Moreover, FMT significantly downregulated the expression levels of Arg-1, S100A8, S100A9, and p47phox as well as ROS production in MDSCs. FMT decreased the percentage of granulocytic MDSCs (G-MDSCs) and promoted the differentiation of MDSCs into macrophages. Furthermore, FMT reduced white blood cell recruitment and alveolar wall thickening in the lungs and areas of necrosis in the liver as well as some biochemical markers of liver dysfunction. FMT decreased the percentage of G-MDSCs and monocytic MDSCs (M-MDSCs) in the spleens of LPS-induced septic mice. Of note, FMT reduced the T cell immunosuppressive functions of both G-MDSCs and M-MDSCs. Expectedly, FMT also significantly reduced Arg-1 and p47phox gene expression in splenic CD11b+Gr-1+ cells isolated from LPS-challenged mice. These data indicate that FMT decreased the immunosuppressive functions of MDSCs by decreasing Arg-1 and ROS production, suggesting that FMT may reduce long-term immunosuppression in the late stage of sepsis.

Author(s):  
Anouk Lepez ◽  
Tiphène Pirnay ◽  
Sébastien Denanglaire ◽  
David Perez-Morga ◽  
Marjorie Vermeersch ◽  
...  

AbstractThe AMP-activated kinase (AMPK) is a major energy sensor metabolic enzyme that is activated early during T cell immune responses but its role in the generation of effector T cells is still controversial.Using both in vitro and in vivo models of T cell proliferation, we show herein that AMPK is dispensable for early TCR signaling and short-term proliferation but required for sustained long-term T cell proliferation and effector / memory T cell survival. In particular, AMPK promoted accumulation of effector / memory T cells in competitive homeostatic proliferation settings. Transplantation of AMPK-deficient hematopoïetic cells into allogeneic host recipients led to a reduced graft-versus-host disease, further bolstering a role for AMPK in the expansion and pathogenicity of effector T cells.Mechanistically, AMPK expression enhances the mitochondrial membrane potential of T cells, limits reactive oxygen species (ROS) production, and resolves ROS-mediated toxicity. Moreover, dampening ROS production alleviates the proliferative defect of AMPK-deficient T cells, therefore indicating a role for an AMPK-mediated ROS control of T cell fitness.


2012 ◽  
Vol 40 (01) ◽  
pp. 1-10 ◽  
Author(s):  
Takahisa Ushiroyama ◽  
Noriko Yokoyama ◽  
Midori Hakukawa ◽  
Kou Sakuma ◽  
Fumio Ichikawa ◽  
...  

Despite the recent technological advances in in vitro fertilization and embryo transfer (IVF-ET), a significant proportion of women still do not become pregnant after long-term infertility, whether it is originally due to older age or other undetermined factors. In the present study, macrophage activating Chinese herbs (MACH) were evaluated for their effects on embryo qualities in women who were undergoing repeated IVF-ET because of long-term infertility. Thirty women, who had significantly low rates of developing good quality cleaved embryos and did not become pregnant after three or more cycles of Assisted Reproductive Technology (ART) procedure, were included in the study. Oral administration of MACH significantly increased the percentage of good quality early stage blastocysts (the number of grade 1 or grade 2 cleaved embryos/the number of retrieved oocytes) from 18.7 ± 16.2% to 36.1 ± 27.1% (1.9-fold increase, p < 0.01). The rate of good quality early stage blastocysts increased in all patients. In 19 patients who desired embryo transfer using late stage blastocysts, MACH significantly increased the percentage of late stage blastocysts from the initial value of 14.8 ± 11.2% to 21.1 ± 23.1% (1.4-fold increase, p < 0.05). The rate of embryonic progress into late stage blastocyst increased in 52.6% (10/19) of the patients. Furthermore, treatment with MACH significantly decreased the plasma follicle stimulating hormone (FSH) concentration on the day of oocyte retrieval from 14.4 ± 3.2 to 10.5 ± 2.4 mIU/ml (p < 0.05). No adverse events were observed with MACH supplementation, and there was no patient dropout. Administration of MACH resulted in improved embryo quality in the difficult cases. The present study demonstrates a new benefit of this herbal blend in women with refractory infertility of unknown etiology.


Author(s):  
D.E. Loudy ◽  
J. Sprinkle-Cavallo ◽  
J.T. Yarrington ◽  
F.Y. Thompson ◽  
J.P. Gibson

Previous short term toxicological studies of one to two weeks duration have demonstrated that MDL 19,660 (5-(4-chlorophenyl)-2,4-dihydro-2,4-dimethyl-3Hl, 2,4-triazole-3-thione), an antidepressant drug, causes a dose-related thrombocytopenia in dogs. Platelet counts started to decline after two days of dosing with 30 mg/kg/day and continued to decrease to their lowest levels by 5-7 days. The loss in platelets was primarily of the small discoid subpopulation. In vitro studies have also indicated that MDL 19,660: does not spontaneously aggregate canine platelets and has moderate antiaggregating properties by inhibiting ADP-induced aggregation. The objectives of the present investigation of MDL 19,660 were to evaluate ultrastructurally long term effects on platelet internal architecture and changes in subpopulations of platelets and megakaryocytes.Nine male and nine female beagle dogs were divided equally into three groups and were administered orally 0, 15, or 30 mg/kg/day of MDL 19,660 for three months. Compared to a control platelet range of 353,000- 452,000/μl, a doserelated thrombocytopenia reached a maximum severity of an average of 135,000/μl for the 15 mg/kg/day dogs after two weeks and 81,000/μl for the 30 mg/kg/day dogs after one week.


2000 ◽  
Vol 111 (1) ◽  
pp. 363-370 ◽  
Author(s):  
Katsuto Takenaka ◽  
Mine Harada ◽  
Tomoaki Fujisaki ◽  
Koji Nagafuji ◽  
Shinichi Mizuno ◽  
...  

1997 ◽  
Vol 56 (1-3) ◽  
pp. 92
Author(s):  
T Anfalova
Keyword(s):  

2011 ◽  
Vol 49 (01) ◽  
Author(s):  
SA Hoffmann ◽  
M Lübberstedt ◽  
U Müller-Vieira ◽  
D Knobeloch ◽  
A Nüssler ◽  
...  

1970 ◽  
Vol 19 (1) ◽  
pp. 89-99
Author(s):  
K. Choudhary ◽  
M. Singh ◽  
M. S. Rathore ◽  
N. S. Shekhawat

This long term study demonstrates for the first time that it is possible to propagate embryogenic Vigna trilobata and to subsequently initiate the differentiation of embryos into complete plantlets. Initiation of callus was possible on 2,4-D. Somatic embryos differentiated on modified MS basal nutrient medium with 1.0 mg/l  of 2,4-D and 0.5 mg/l  of Kn. Sustained cell division resulted in globular and heart shape stages of somatic embryos. Transfer of embryos on to a fresh modified MS basal medium with 0.5 mg/l of Kn and 0.5 mg/l of GA3 helped them to attain maturation and germination. However, the propagation of cells, as well as the differentiation of embryos, were inhibited by a continuous application of these growth regulators. For this reason, a long period on medium lacking these growth regulators was necessary before the differentiation of embryos occurred again. The consequences for improving the propagation of embryogenic cultures in Vigna species are discussed. Key words: Pasture  legume, Vigna trilobata, Globular, Heart shape, somatic embryogenesis D.O.I. 10.3329/ptcb.v19i1.4990 Plant Tissue Cult. & Biotech. 19(1): 89-99, 2009 (June)


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