Exosome-Depleted Excretory-Secretory Products of the Fourth-Stage Larval Angiostrongylus cantonensis Promotes Alternative Activation of Macrophages Through Metabolic Reprogramming by the PI3K-Akt Pathway.

Angiostrongylus cantonensis (AC), which parasitizes in the brain of the non-permissive host, such as mouse and human, is an etiologic agent of eosinophilic meningitis. Excretory-secretory (ES) products play an important role in the interaction between parasites and hosts' immune responses. Inflammatory macrophages are responsible for eosinophilic meningitis induced by AC, and the soluble antigens of Angiostrongylus cantonensis fourth stage larva (AC L4), a mimic of dead AC L4, aggravate eosinophilic meningitis in AC-infected mice model via promoting alternative activation of macrophages. In this study, we investigated the key molecules in the ES products of AC L4 on macrophages and observed the relationship between metabolic reprogramming and the PI3K-Akt pathway. First, a co-culture system of macrophage and AC L4 was established to define the role of AC L4 ES products on macrophage polarization. Then, AC L4 exosome and exosome-depleted excretory-secretory products (exofree) were separated from AC L4 ES products using differential centrifugation, and their distinct roles on macrophage polarization were confirmed using qPCR and ELISA experiments. Moreover, AC L4 exofree induced alternative activation of macrophages, which is partially associated with metabolic reprogramming by the PI3K-Akt pathway. Next, lectin blot and deglycosylation assay were done, suggesting the key role of N-linked glycoproteins in exofree. Then, glycoproteomic analysis of exofree and RNA-seq analysis of exofree-treated macrophage were performed. Bi-layer PPI network analysis based on these results identified macrophage-related protein Hexa as a key molecule in inducing alternative activation of macrophages. Our results indicate a great value for research of helminth-derived immunoregulatory molecules, which might contribute to drug development for immune-related diseases.

Functional Characteristics and Application of Mesenchymal Stem Cells in Systemic Lupus Erythematosus.

Systemic lupus erythematosus (SLE) is a rare, heterogeneous autoimmune and autoinflammatory disease that affects both sexes and all races, although this disease exhibits its highest incidence/prevalence among the black population and shows a predilection for women of reproductive age. Although SLE has no cure, treatment can help decrease its signs and symptoms. Thus, we should focus primarily on personalized treatment. Mesenchymal stem/stromal cells (MSCs), which are multipotent cells capable of differentiating into osteoblasts, chondrocytes, adipocytes, and myoblasts, among other cell types, are potential candidates for use in a promising strategy to treat severe and refractory SLE. MSCs have an immunomodulatory function that can suppress the proliferation and activities of many immune cells, such as T lymphocytes, B lymphocytes, natural killer cells, macrophages and dendritic cells. Substantial progress has recently been made in MSC therapy, and experimental and clinical data suggest that such a therapy is a promising strategy for the treatment of severe and refractory SLE. In this review, we highlight the effects of MSCs on different immune cell types, describe the mechanisms underlying MSC-mediated immunoregulation, and discuss the treatment of SLE with MSCs from different sources in various animal models and clinical applications.

Up-regulated miR-155 is associated with poor prognosis in childhood acute lymphoblastic leukemia and promotes cell proliferation targeting ZNF238.

OBJECTIVES: Acute lymphoblastic leukemia (ALL) is one of the most common malignancies in children. Our aim was to identify a novel miRNA that can predict prognosis of childhood ALL patients and explore its potential mechanism. METHODS: The miRNA expression profiles of childhood ALL were analyzed using GEO database and HiSeq instruments. The expression of miR-155 was examined by RT-PCR in 42 ALL patients. To investigate the role of miR-155 in ALL, four ALL cell lines (CEM-C1, Jurkat, MOLT-3 and MOLT-4) were transfected with miR-155 mimics, miR-155 inhibitors or corresponding controls. Dual-luciferase reporter system was applied to confirm the miR-155 target ZNF238. Moreover, proliferation and apoptosis were evaluated by MTT and flow cytometry. RESULTS: Dataset GSE56489 and GSE23024 demonstrated that miR-155 was up-regulated and ZNF238 was down-regulated at diagnosis status of ALL. High miR-155 expression was associated with poor outcome. Overexpressed miR-155 promoted ALL cell proliferation and inhibited apoptosis. Dual-luciferase reporter result showed that miR-155 directly regulated ZNF238. Silencing ZNF238 promoted cell proliferation in ALL cells. DISCUSSION: Our research indicating that miR-155 might possess potential value as a biomarker for predicting the prognosis of individuals. However, the role of ZNF238 in childhood ALL remain unknown. In the present study, we found the possible role of ZNF238 as a new tumor suppressor in ALL, which might be necessary for the antiproliferative functions of normal cells to counteract ALL formation. CONCLUSION: Our results propose that miR-155 is in association with poor prognosis of childhood ALL. Furthermore, miR-155 could promote cell proliferation targeting ZNF238.

Encephalopathy and brain atrophy during induction chemotherapy in acute lymphoblastic leukemia.

The MRI showed encephalopathy and brain atrophy of the left parietal lobe, occipital lobe and temporal lobe and decreased infiltration of the dura mater on T2-weighted imaging. But encephalopathy and brain atrophy could be improved with neurotrophic drugs and additional intelligence teaching.

Arsenic trioxide and all-trans retinoic acid suppress the expression of FLT3-ITD.

The prognosis of patients with acute myeloid leukemia (AML) caused by the FLT3-ITD mutation is poor. Arsenic trioxide (ATO) and all-trans retinoic acid (ATRA) can down-regulate FLT3-ITD level and selectively kill leukemia cells carrying the FLT3-ITD mutation. However, the mechanisms of action of these two compounds are unknown. Here, we found that ATO could bind FLT3-ITD at Lys91 and Asp225, whereas ATRA could bind FLT3-ITD at Lys5 and Gln6. Both compounds could not bind wild-type FLT3. Further studies revealed that ATO/ATRA may suppress the Expression of FLT3-ITD by promoting the UBE2L6-mediated ubiquitination pathway and decreasing the expression of C-MYC. However, further studies are needed to define the mechanisms of these compounds on AML. Our research provides an experimental basis for the use of ATO/ATRA in FLT3-ITD AML in clinical practice.

Melatonin inhibits MLL-rearranged leukemia via RBFOX3/hTERT and NF-κB/COX-2 signaling pathways.

MLL-rearranged leukemia is an aggressive malignancy associated with poor outcome, which is refractory to conventional treatment. Melatonin has been proven to exert anti-tumor activity, but the effect of melatonin on MLL-r leukemia and the underlying mechanism remain poorly understood. In this study, melatonin inhibited cell proliferation and induced apoptosis by activating the caspase-dependent apoptotic pathway in MLL-r leukemia cells. Mechanistic investigations revealed that melatonin suppressed the expression of hTERT by abrogating the binding activity of RBFOX3 to the hTERT promoter. Melatonin also blocked NF-κB nuclear translocation and suppressed NF-κB binding to the COX-2 promoter, thereby suppressing the expression of COX-2. In addition, clinical samples revealed that melatonin exerts anti-leukemic activity in primary MLL-r leukemia blasts ex vivo. In vivo, the mice treated with melatonin experienced a larger reduction in leukemic burden than the control group in a MLL-r leukemia xenograft mouse model. Collectively, these results suggest that melatonin inhibits MLL-rearranged leukemia through suppressing the RBFOX3/hTERT and NF-κB/COX-2 signaling pathways. Our findings provide new insights into the role of melatonin for MLL-r leukemia treatment.

Effect of T helper cell 1/T helper cell 2 balance and nuclear factor-κB on white matter injury in premature neonates.

Incidence of white matter injury (WMI), which is featured as softening of white matter tissues, has recently increased. Previous studies have demonstrated a close correlation between T helper cell 1 and T helper cell 2 (Th1/Th2) imbalance and nuclear factor­κB (NF­κB) with brain disease. Their role in premature WMI, however, remains to be illustrated. Serum samples were collected from 60 premature WMI neonates, plus another control group of 60 premature babies without WMI. Patients were further divided into mild, moderate and severe WMI groups. Reverse transcription quantitative polymerase chain reaction was used to test mRNA expression levels of Th1/Th2 cytokines, including interleukin 2 (IL)­2, tumor necrosis factor­α (TNF­α), IL­4, IL­10 and nuclear factor (NF)­κB, whilst their serum levels were measured by ELISA. Their correlation with disease occurrence and progression were further analysed, to illustrate the effect of Th1/Th2 balance and NF­κB on pathology of premature WMI. Serum levels of IL­4 and IL­10 were significantly decreased in premature WMI babies, whilst IL­2, TNF­α and NF­κB were upregulated (P<0.05 vs. control group). With aggravated disease, IL­4 and IL­10 expression was further decreased while IL­2, TNF­α and NF­κB were increased (P<0.05 vs. mild WMI group). Th1 cytokines IL­2 and TNF­α and NF­κB were negatively correlated with Th2 cytokines IL­4 and IL­10. Disease severity was positively correlated with IL­2, TNF­α and NF­κB expression, and was negatively correlated with IL­4 and IL­10 (P<0.05). Th1/Th2 imbalance and NF­κB upregulation were observed in WMI pathogenesis, with elevated secretion of Th1 cytokines and decreased Th2 cytokines, suggesting that Th1/Th2 imbalance and NF­κB upregulation may be a potential indicator for the early diagnosis and treatment of WMI pathogenesis and progression.

Protective effect of miconazole on rat myelin sheaths following premature infant cerebral white matter injury.

The aim of the present study was to investigate the protective effects of miconazole on myelin sheaths following cerebral white matter damage (WMD) in premature infant rats. Sprague Dawley rats (3-days-old) were randomly divided into four groups (n=30 each) as follows: Sham surgery group, WMD model group, 10 mg/kg/day treatment group and 40 mg/kg/day treatment group. A cerebral white matter lesion model was created by ligating the right common carotid artery for 80 min. Treatment groups were administered with 10 or 40 mg/kg miconazole at 4-8 days following birth (early treatment group) or 5-11 days following birth (late treatment group). Rats in the model group received the same concentration of dimethylsulfoxide. Myelin basic protein (MBP) immunohistochemical staining and western blotting were used to detect the expression of cerebral white matter-specific MBP, and changes in myelin structure were observed using transmission electron microscopy. No swelling or necrosis was observed in the corpus callosum of the sham group rats, whereas rats in the model group demonstrated edema, loose structure, fiber disorder, inflammatory gliocytes and selective white matter lesions. Following treatment with miconazole, MBP expression in the corpus callosum was significantly higher compared with the model group. Furthermore, in the model group, myelin sheaths in the corpus callosum were loose with small vacuoles, there was a marked decrease in thickness and structural damage was observed. Conversely, a marked improvement in myelination was observed in the treatment group. The results of the present study suggest that miconazole is able to promote formation of the myelin sheath to ameliorate premature cerebral white matter lesions caused by ischemia or hypoxia in rats.