搜索结果: 'methocult media formulations for human hematopoietic cells serum containing'

Induction of ferroptosis,an iron-dependent form of regulated cell death,holds promise as a strategy to overcome tumor resistance to conventional therapies and enhance immunotherapy responses. However,while the susceptibility of tumor cells to ferroptosis is extensively studied,limited data exists on the vulnerability of immune cells to disturbed iron balance and lipid peroxidation. Here,we found that T-cell stimulation rewires iron and redox homeostasis and by increasing levels of reactive oxygen species and labile iron promotes lipid peroxidation and T-cells’ ferroptosis. Upon stimulation,we detected changes in the balance of ferroptosis-suppressive proteins,including decrease of GPX4. Subsequently,we identified GPX4 as a master regulator orchestrating T/CAR-T-cells’ sensitivity to ferroptosis and observed that GPX4 inhibitors impair CAR-T cells’ antitumor functions. Our study demonstrated differential GPX4 expression and diverse susceptibility to ferroptosis between CD4⁺ and CD8⁺ T cells. Among analyzed subsets of naïve,central memory (CM),effector memory (EM),and terminally differentiated effector memory (TEMRA),CD8⁺ EM and CD8⁺ TEMRA cells exhibited the highest sensitivity to ferroptosis. We also showed that ferroptosis limited the anti-tumor efficacy of CAR-T cells,while ferroptosis inhibition improved their therapeutic effect,both in vitro and in vivo. Our findings are not only important to understand vulnerabilities of CAR-T cells but may also hold particular significance for their therapeutic development. In this context,future anticancer therapies should be carefully designed to selectively induce the ferroptosis of tumor cells without impeding cytotoxic cells’ antitumor efficacy. Additionally,we postulate that promoting less differentiated phenotype of CAR-T cells should be exploited therapeutically to create CAR-T products characterized by decreased sensitivity to ferroptosis within tumor microenvironment.Supplementary InformationThe online version contains supplementary material available at 10.1007/s00262-025-04133-w. View Publication

Acute myeloid leukemia (AML) is an aggressive hematologic malignancy with a poor prognosis and limited therapeutic options. Leukemic stem cells (LSCs),which drive disease progression and confer resistance to therapy,pose a significant challenge to conventional treatment strategies. In this study,we identified and characterized the inhibitory mechanisms of TH37,a small molecule derived from traditional Chinese medicine,which selectively targets AML blasts and LSCs. Our analyses identified peroxiredoxin 1 (PRDX1),an enzyme that catalyzes the breakdown of hydrogen peroxide (a reactive oxygen species),as the primary molecular target of TH37. We demonstrated that TH37 directly interacts with PRDX1,inhibiting its enzymatic activity and thereby elevating intracellular reactive oxygen species levels in AML cells. PRDX1 was found to be overexpressed in AML,and its expression correlated with poor prognosis and the activation of AML- and cancer-associated pathways. Targeting PRDX1,either through lentiviral short-hairpin RNA-mediated silencing or TH37 treatment,induced apoptosis,reduced colony formation,and impaired the engraftment and growth of AML cells in immunodeficient mouse models. Furthermore,TH37 synergized with conventional chemotherapeutic agent to significantly reduce the viability and colony-forming capacity of AML cells. These findings demonstrate the critical role of PRDX1 in AML pathogenesis and highlight its potential as a key therapeutic target to improve clinical outcomes for AML patients. View Publication

Converging evidence indicates that extra-embryonic yolk sac is the source of both macrophages and endothelial cells in adult mouse tissues. Prevailing views are that these embryonically derived cells are maintained after birth by proliferative self-renewal in their differentiated states. Here we identify clonogenic endothelial-macrophage (EndoMac) progenitor cells in the adventitia of embryonic and postnatal mouse aorta,that are independent of Flt3-mediated bone marrow hematopoiesis and derive from an early embryonic CX 3 CR1 + and CSF1R + source. These bipotent progenitors are proliferative and vasculogenic,contributing to adventitial neovascularization and formation of perfused blood vessels after transfer into ischemic tissue. We establish a regulatory role for angiotensin II,which enhances their clonogenic and differentiation properties and rapidly stimulates their proliferative expansion in vivo. Our findings demonstrate that embryonically derived EndoMac progenitors participate in local vasculogenic responses in the aortic wall by contributing to the expansion of endothelial cells and macrophages postnatally. Subject terms: Angiogenesis,Myelopoiesis,Haematopoietic stem cells View Publication

PRDX2 is significantly expressed in various cancers and is associated with the proliferation of tumor cells. Nonetheless,the precise mechanism of PRDX2 in tumor immunity remains incompletely understood. This study aims to investigate the impact of PRDX2,which is highly expressed in lung adenocarcinoma,on T cells in the tumor immune microenvironment,and its immune action target to promote the immune escape of lung cancer cells,to provide a theoretical basis for lung adenocarcinoma treatment with PRDX2 as the target. Mouse animal models to verify the effect of Conoidin A treatment on tumor growth and T cell infiltration. Flow cytometry and Western blot verified tumor cell apoptosis in the in vitro co-culture system as well as granzyme B and perforin expression in T cells. RNA-Seq was used to obtain the downstream immune molecule. si-RNA knockdown of Galectin-9 was co-cultured with T cells in vitro. Immunofluorescence and Western blot verified that PRDX2 regulates Galectin-9 expression through HDAC3. PRDX2 expression was negatively correlated with CD8 + T cell expression in LUAD patients. Inhibition of PRDX2 significantly enhanced T-cell killing of LUAD cells and reduced tumor load in both in vitro and in vivo models. Mechanistically,Conoidin A or shRNA_PRDX2 decreased Galectin-9 expression by down-regulating the phosphorylation of HDAC3,consequently enhancing the infiltration and function of CD8 + T cells. This study reveals the role of the PRDX2/HDAC3/Galectin-9 axis in LUAD immune escape and indicates Galectin-9 as a promising target for immunotherapy. The online version contains supplementary material available at 10.1186/s12967-024-05888-z. View Publication

Cell therapy is promising for heart failure treatment,with growing interest in cardiovascular progenitor cells (CPCs) from pluripotent stem cells. A major challenge is managing the immune response,due to their allogeneic source. Regulatory T cells (Treg) offer an alternative to pharmacological immunosuppression by inducing immune tolerance. This study assesses whether Treg therapy can mitigate the xeno-immune response,improving cardiac outcomes in a mouse model of human CPC intramyocardial transplantation. CPCs stimulated immune responses in allogeneic and xenogeneic settings,causing proliferation in T cell subsets. Tregs showed immunosuppressive effects on T lymphocyte populations when co-cultured with CPCs. Post infarction,CPCs were transplanted intramyocardially into an immune-competent mouse model 3 weeks after myocardial infarction. Human or murine Tregs were intravenously administered on transplantation day and three days later. Control groups received CPCs without Tregs or saline (PBS). CPCs with Tregs improved LV systolic function in three weeks,linked to reduced myocardial fibrosis and enhanced angiogenesis. This was accompanied by decreased splenocyte NK cell populations and pro-inflammatory cytokine levels in cardiac tissue. Treg therapy with CPC transplantation enhances cardiac functional and structural outcomes in mice. Though it does not directly avert graft rejection,it primarily affects NKG2D+ cytotoxic cells,indicating systemic immune modulation and remote heart repair benefits. View Publication

Background: Recurrent/metastatic head and neck squamous cell carcinoma ((R/M) HNSCC) represents one of the most aggressive and immunosuppressive cancers. Despite the introduction of immune checkpoint inhibitors (ICIs),only a limited number of patients obtain long-term benefits. In (R/M) HNSCC patients,the antitumor immune response is defective,conferring resistance and promoting tumor progression. Therefore,the identification of novel biomarkers for superior clinical outcomes and easily accessible in standard clinical settings is still an unmet clinical need. Methods: Blood liquid biopsies obtained from (R/M) HNSCC patients undergoing pembrolizumab therapy (monotherapy or in combination with chemotherapy) were analyzed by flow cytometry to evaluate the levels of circulating immunosuppressive regulatory T cells (Tregs) and myeloid derived suppressor cells (MDSCs),at baseline and during therapy. Correlations between these immunosuppressive immune cell subsets and clinical parameters (clinical response rate,progression-free survival (PFS),overall survival (OS) and performance status (PS)) were performed. Results: Univariate analysis showed that before therapy,higher circulating levels of both CD137⁺Tregs and LOX-1⁺PMN-MDSCs,identified patients with significantly worse survival. Furthermore,CD137⁺Tregs resulted also positively correlated with worse PS,while high levels of LOX-1⁺PMN-MDSCs negatively affected response to pembrolizumab,with a significant increase in non-responsive patients during therapy. Interestingly,both CD137⁺Tregs as well as LOX-1⁺PMN-MDSCs exerted a higher immunosuppression on T cell proliferation than CD137−Tregs and LOX-1⁻PMN-MDSCs,respectively. Multivariate analysis revealed that the circulating LOX-1⁺PMN-MDSC subset resulted as an independent prognostic factor for survival by multivariate analysis,as confirmed in an independent validation cohort. Conclusions: The levels of blood circulating LOX-1⁺PMN-MDSCs may be proposed as non-invasive biomarkers to predict clinical outcomes of (R/M) HNSCC patients developing resistance to immunotherapy,improving patient selection and suggesting novel personalized therapies. View Publication

BACKGROUND: Transforming growth factor beta (TGF-beta) plays an important role in skeletal remodelling. However,few studies have examined its effects on cultured human osteoblasts. Our aim is to characterise the biological effects of TGF-beta1 on human osteoblasts and to examine the interaction between TGF-beta1 and calcitriol. DESIGN: In vitro study employing two models of normal human osteoblasts: human bone marrow stromal cells [hMS/(OB)] containing osteoprogenitor cells and trabecular bone osteoblasts (hOB),which are mature osteoblasts. A reverse-transcriptase-polymerase-chain-reaction assay was employed to measure steady state mRNA levels of TGF-beta(s) isoforms and receptors. Effects of short-term treatment of TGF-beta1 on osteoblast proliferation and differentiation markers were assessed. The effect of cotreatment of calcitriol (10-8 M) and TGF-beta1 on osteoblast differentiation was also determined. RESULTS: Both hMS(OB) and hOB cells expressed mRNA transcripts of TGF-beta1,TGF-beta2,TGF-beta 3,TGF-beta type I and type II receptors. TGF-beta 1 stimulated osteoblast proliferation in hMS(OB) and in hOB cultures. In hOB cultures,TGF-beta1 stimulated AP production and cotreatment with calcitriol induced a synergistic increase in AP levels to 250 +/- 61% of calcitriol-treated controls. Effects of TGF-beta1 and calcitriol were less pronounced in hMS(OB) cultures. TGF-beta1 inhibited collagen type I production in hMS(OB) cells and these effects were abolished in presence of calcitriol. In presence of calcitriol,TGF-beta1 increased collagen type I production in hOB cells. In both hOB and hMS(OB) cultures,TGF-beta1 inhibited osteocalcin production. CONCLUSIONS: TGF-beta increases osteoblastic cell proliferation irrespective of the differentiation state. In presence of calcitriol,it initiates osteoblast cell differentiation and matrix formation. As TGF-beta inhibits osteocalcin production,other factors are necessary for inducing terminal differentiation of osteoblasts. The observed effects of TGF-beta on human osteoblasts in vitro may represent important regulatory steps in controlling osteoblast cell proliferation and differentiation in vivo. View Publication

Mutations in SCN1A,the gene encoding the α subunit of Nav1.1 channel,can cause epilepsies with wide ranges of clinical phenotypes,which are associated with the contrasting effects of channel loss-of-function or gain-of-function. In this project,CRISPR/Cas9- and TALEN-mediated genome-editing techniques were applied to induced pluripotent stem cell (iPSC)-based-disease model to explore the mechanism of epilepsy caused by SCN1A loss-of-function mutation. By fluorescently labeling GABAergic subtype in iPSC-derived neurons using CRISPR/Cas9,we for the first time performed electrophysiological studies on SCN1A-expressing neural subtype and monitored the postsynaptic activity of both inhibitory and excitatory types. We found that the mutation c.A5768G,which led to no current of Nav1.1 in exogenously transfected system,influenced the properties of not only Nav current amount,but also Nav activation in Nav1.1-expressing GABAergic neurons. The two alterations in Nav further reduced the amplitudes and enhanced the thresholds of action potential in patient-derived GABAergic neurons,and led to weakened spontaneous inhibitory postsynaptic currents (sIPSCs) in the patient-derived neuronal network. Although the spontaneous excitatory postsynaptic currents (sEPSCs) did not change significantly,when the frequencies of both sIPSCs and sEPSCs were further analyzed,we found the whole postsynaptic activity transferred from the inhibition-dominated state to excitation in patient-derived neuronal networks,suggesting that changes in sIPSCs alone were sufficient to significantly reverse the excitatory level of spontaneous postsynaptic activity. In summary,our findings fill the gap of our knowledge regarding the relationship between SCN1A mutation effect recorded on exogenously transfected cells and on Nav1.1-expressing neurons,and reveal the physiological basis underlying epileptogenesis caused by SCN1A loss-of-function mutation. View Publication

Recent work investigating exercise induced changes in immunocompetence suggests that some of the ambiguity in the literature is resultant from different cell isolation protocols and mitogen selection. To understand this effect,we compared post-exercise measures of T cell activation and proliferation using two different stimulation methods (costimulation through CD28 or stimulation with phytohaemagglutinin [PHA]). Further,we investigated whether exercise induced changes are maintained when T cell isolation from whole blood is delayed overnight in either a room temperature or chilled (4°C) environment. As expected,an increased proliferation response was observed post-exercise in T cells isolated from whole blood of previously trained individuals immediately after blood collection. Also,cells stimulated with PHA after resting overnight in whole blood were not adversely impacted by the storage conditions. In contrast,allowing cells to rest overnight in whole blood prior to stimulation through CD28,lessened the proliferation observed by cells following exercise rendering both the room temperature and chilled samples closer to the results seen in the control condition. Changes in early markers of activation (CD25),followed a similar pattern,with activation in PHA stimulated cells remaining fairly robust after overnight storage; whereas cell activation following stimulation through CD3+CD28 was disproportionately decreased by the influence of overnight storage. These findings indicate that decisions regarding cell stimulation methods need to be paired with the timeline for T cell isolation from whole blood. These considerations will be especially important for field based studies of immunocompetence where there is a delay in getting whole blood samples to a lab for processing as well as clinical applications where a failure to isolate T cells in a timely manner may result in loss of the response of interest. View Publication

UNLABELLED: Human stem cells from adult sources have been shown to contribute to the regeneration of muscle,liver,heart,and vasculature. The mechanisms by which this is accomplished are,however,still not well understood. We tested the engraftment and regenerative potential of human umbilical cord blood-derived ALDH(hi)Lin(-),and ALDH(lo)Lin(-) cells following transplantation to NOD/SCID or NOD/SCID beta2m null mice with experimentally induced acute myocardial infarction. We used combined nanoparticle labeling and whole organ fluorescent imaging to detect human cells in multiple organs 48 hours post transplantation. Engraftment and regenerative effects of cell treatment were assessed four weeks post transplantation. We found that ALDH(hi)Lin(-) stem cells specifically located to the site of injury 48 hours post transplantation and engrafted the infarcted heart at higher frequencies than ALDH(lo)Lin(-) committed progenitor cells four weeks post transplantation. We found no donor derived cardiomyocytes and few endothelial cells of donor origin. Cell treatment was not associated with any detectable functional improvement at the four week endpoint. There was,however,a significant increase in vascular density in the central infarct zone of ALDH(hi)Lin(-) cell-treated mice,as compared to PBS and ALDH(lo)Lin(-) cell-treated mice. CONCLUSIONS: Our data indicate that adult human stem cells do not become a significant part of the regenerating tissue,but rapidly home to and persist only temporarily at the site of hypoxic injury to exert trophic effects on tissue repair thereby enhancing vascular recovery. View Publication

Telomerase plays an important role in governing the life span of cells for its capacity to extend telomeres. As high activity of telomerase has been found in stem cells and cancer cells specifically,various methods have been developed for the evaluation of telomerase activity. To overcome the time-consuming procedures and complicated manipulations of existing methods,we developed a novel method named Telomeric Repeat Elongation Assay based on Quartz crystal microbalance (TREAQ) to monitor telomerase activity during the self-renewal and differentiation of human induced pluripotent stem cells (hiPSCs). TREAQ results indicated hiPSCs possess invariable telomerase activity for 11 passages on Matrigel and a steady decline of telomerase activity when differentiated for different periods,which is confirmed with existing golden standard method. The pluripotency of hiPSCs during differentiation could be estimated through monitoring telomerase activity and compared with the expression levels of markers of pluripotency gene via quantitative real time PCR. Regular assessment for factors associated with pluripotency or stemness was expensive and requires excessive sample consuming,thus TREAQ could be a promising alternative technology for routine monitoring of telomerase activity and estimate the pluripotency of stem cells. View Publication