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Enhanced inflammatory response and oxidative stress cause acute lung injury (ALI). Controlling inflammation and oxidation can ameliorate ALI. In the present study, we aimed to determine whether 3,4 -Dihydroxyacetophenone (compound 1) could ameliorate lipopolysaccharide (LPS)-induced ALI by suppressing inflammation and oxidation. In this study, compound 1 reduced LPS-induced inflammatory cytokines and oxidative stress in RAW 264.7 cells. Moreover, compound 1 suppressed the expression of inflammatory protein p65, inhibited IkBa phosphorylation, decreased the nuclear translocation of p65, and increased the expressions of anti-oxidative protein nuclear factor erythroid 2-related factor 2 (Nrf-2) and heme oxygenase-1 (HO-1), which was reduced by LPS, in leukemia cells in mouse macrophage (RAW 264.7) cells. Furthermore, compound 1 could also ameliorate LPS-induced ALI in vivo, with a reduction of inflammatory cytokines, oxidative stress, and nuclear factor-kappa B (NF-kB) signaling pathway activation. This study emphasized the anti-inflammatory and anti-oxidative activities of compound 1, which could be a valuable therapeutic agent against ALI. [ABSTRACT FROM AUTHOR]

HIV-1-specific CD8+ T cells are an important component of HIV-1 curative strategies. Viral variants in the HIV-1 reservoir may limit the capacity of T cells to detect and clear virus-infected cells. We investigated the patterns of T cell escape variants in the replication-competent reservoir of 25 persons living with HIV-1 (PLWH) durably suppressed on antiretroviral therapy (ART). We identified all reactive T cell epitopes in the HIV-1 proteome for each participant and sequenced HIV-1 outgrowth viruses from resting CD4+ T cells. All non-synonymous mutations in reactive T cell epitopes were tested for their effect on the size of the T cell response, with a=50% loss defined as an escape mutation. The majority (68%) of T cell epitopes harbored no detectable escape mutations. These findings suggest that circulating T cells in PLWH on ART could contribute to control of rebound and could be targeted for boosting in curative strategies. [ABSTRACT FROM AUTHOR]

Calcium influx from depolarized CaV1.2 calcium channels triggers the contraction of vascular smoothmuscle cells (VSMCs), which is important formaintaining vascular myogenic tone and blood pressure. The function of CaV1.2 channel can be subtly modulated by alternative splicing (AS), and its aberrant splicing involves in the pathogenesis ofmultiple cardiovascular diseases. The RNA-binding protein Rbfox1 is reported to regulate the AS events of CaV1.2 channel in the neuronal development, but its potential roles in vascular CaV1.2 channels and vasoconstriction remain undefined. Here, we detect Rbfox1 is expressed in rat vascular smooth muscles. Moreover, the protein level of Rbfox1 is dramatically decreased in the hypertensive small arteries from spontaneously hypertensive rats in comparison with normotensive ones from Wistar-Kyoto rats. In VSMCs, Rbfox1 could dynamically regulate the AS of CaV1.2 exons 9* and 33. By whole-cell patch clamp, we identify knockdown of Rbfox1 induces the hyperpolarization of CaV1.2 current--voltage relationship curve in VSMCs. Furthermore, siRNA-mediated knockdown of Rbfox1 increases the K+-induced constriction of rat mesenteric arteries. In summary, our results indicate Rbfox1 modulates vascular constriction by dynamically regulating CaV1.2 alternative exons 9* and 33. Therefore, our work elucidates the underlying mechanisms for CaV1.2 channels regulation and provides a potential therapeutic target for hypertension. [ABSTRACT FROM AUTHOR]

Juvenile myelomonocytic leukemia (JMML), a rare and aggressive myelodysplastic/myeloproliferative neoplasm that occurs in infants and during early childhood, is characterized by excessive myelomonocytic cell proliferation. More than 80% of patients harbor germ line and somatic mutations in RAS pathway genes (eg, PTPN11, NF1, NRAS, KRAS, and CBL), and previous studies have identified several biomarkers associated with poor prognosis. However, the molecular pathogenesis of 10% to 20% of patients and the relationships among these biomarkers have not been well defined. To address these issues, we performed an integrated molecular analysis of samples from 150 JMML patients. RNA-sequencing identified ALK/ROS1 tyrosine kinase fusions (DCTN1-ALK, RANBP2-ALK, and TBL1XR1-ROS1) in 3 of 16 patients (18%) who lacked canonical RAS pathway mutations. Crizotinib, an ALK/ROS1 inhibitor, markedly suppressed ALK/ROS1 fusion-positive JMML cell proliferation in vitro. Therefore, we administered crizotinib to a chemotherapy-resistant patient with the RANBP2-ALK fusion who subsequently achieved complete molecular remission. In addition, crizotinib also suppressed proliferation of JMML cells with canonical RAS pathway mutations. Genome-wide methylation analysis identified a hypermethylation profile resembling that of acute myeloid leukemia (AML), which correlated significantly with genetic markers with poor outcomes such as PTPN11/NF1 gene mutations, 2 or more genetic mutations, an AML-type expression profile, and LIN28B expression. In summary, we identified recurrent activated ALK/ROS1 fusions in JMML patients without canonical RAS pathway gene mutations and revealed the relationships among biomarkers for JMML. Crizotinib is a promising candidate drug for the treatment of JMML, particularly in patients with ALK/ROS1 fusions. [ABSTRACT FROM AUTHOR]

Background: The histone deacetylase (HDAC) inhibitor vorinostat (VOR) can increase HIV RNA expression in vivo within resting CD4+ T cells of aviremic HIV+ individuals. However, while studies of VOR or other HDAC inhibitors have reported reversal of latency, none has demonstrated clearance of latent infection. We sought to identify the optimal dosing of VOR for effective serial reversal of HIV latency.Methods: In a study of 16 HIV-infected, aviremic individuals, we measured resting CD4+ T cell-associated HIV RNA ex vivo and in vivo following a single exposure to VOR, and then in vivo after a pair of doses separated by 48 or 72 hours, and finally following a series of 10 doses given at 72-hour intervals.Results: Serial VOR exposures separated by 72 hours most often resulted in an increase in cell-associated HIV RNA within circulating resting CD4+ T cells. VOR was well tolerated by all participants. However, despite serial reversal of latency over 1 month of VOR dosing, we did not observe a measurable decrease (>0.3 log10) in the frequency of latent infection within resting CD4+ T cells.Conclusions: These findings outline parameters for the experimental use of VOR to clear latent infection. Latency reversal can be achieved by VOR safely and repeatedly, but effective depletion of persistent HIV infection will require additional advances. In addition to improvements in latency reversal, these advances may include the sustained induction of potent antiviral immune responses capable of recognizing and clearing the rare cells in which HIV latency has been reversed.Trial Registration: Clinicaltrials.gov NCT01319383.Funding: NIH grants U01 AI095052, AI50410, and P30 CA016086 and National Center for Advancing Translational Sciences grant KL2 TR001109. [ABSTRACT FROM AUTHOR]

Myelodysplastic/myeloproliferative uclassifiable ( MDS/ MPN- U) is a rare myeloid neoplasm characterized by myelodysplasia and myeloproliferation at the time of initial presentation, which is usually a diagnosis of exclusion. The molecular pathogenesis of MDS/ MPN- U patients remains to be elucidated. Among five patients diagnosed with MDS/ MPN- U, three patients harboured RUNX1 ( AML1) mutations; one carried somatic mosaicism of RUNX1 mutation with JAK2V617F mutation and one had dual RUNX1 and FLT3-internal tandem duplication mutations with progression to acute myeloid leukaemia ( AML). Germline mutation of TP53 was detected as a sole genetic lesion in one patient. JAK2V617F and somatic mosaicism of KRAS and TET2 mutations co-existed in one patient. Otherwise, no alterations were detected in PTPN11, NRAS, CBL and ASXL1 genes. ETV6- PDGFRB fusion transcript was not detected in all patients. Four patients recieved haematopoietic stem cell transplantation ( HSCT); three patients relapsed and one achieved complete remission after three donor lymphocyte infusions. Our findings suggest that the mutational spectrum observed in childhood MDS/ MPN- U is quite different from that seen in juvenile myelomonocytic leukaemia and, to some extent, resemble chronic myelomonocytic leukaemia. Moreover, two patients had constitutional alterations of genes frequently found in AML. Further investigations are required to define the roles of these genetic alterations in the pathogenesis of childhood MDS/ MPN- U. [ABSTRACT FROM AUTHOR]

Ipilimumab, a monoclonal antibody against cytotoxic T lymphocyte antigen 4 (CTLA-4), has been shown to improve survival in patients with advanced metastatic melanoma. It also enhances immunity to NY-ESO-1, a cancer/testis antigen expressed in a subset of patients with melanoma. To characterize the association between immune response and clinical outcome, we first analyzed NY-ESO-1 serum antibody by ELISA in 144 ipilimumab-treated patients with melanoma and found 22 of 140 (16%) seropositive at baseline and 31 of 144 (22%) seropositive following treatment. These NY-ESO-1-seropositive patients had a greater likelihood of experiencing clinical benefit 24 wk after ipilimumab treatment than NY-ESO-1-seronegative patients (P = 0.02, relative risk = 1.8, two-tailed Fisher test). To understand why some patients with NY-ESO-1 antibody failed to experience clinical benefit, we analyzed NY-ESO-1-specific CD4+ and CD8+ T-cell responses by intracellular multicytokine staining in 20 NY-ESO-1-seropositive patients and found a surprising dissociation between NY-ESO-1 antibody and CD8 responses in some patients. NY-ESO-1-seropositive patients with associated CD8+ T cells experienced more frequent clinical benefit (10 of 13; 77%) than those with undetectable CD8+ T-cell response (one of seven; 14%; P = 0.02; relative risk = 5.4, two-tailed Fisher test), as well as a significant survival advantage (P = 0.01; hazard ratio = 0.2, time-dependent Cox model). Together, our data suggest that integrated NY-ESO-1 immune responses may have predictive value for ipilimumab treatment and argue for prospective studies in patients with established NY-ESO-1 immunity. The current findings provide a strong rationale for the clinical use of modulators of immunosuppression with concurrent approaches to favor tumor antigen-specific immune responses, such as vaccines or adoptive transfer, in patients with cancer. [ABSTRACT FROM AUTHOR]

Mutations in NF1, PTPN11, NRAS, KRAS and CBL have been reported to play a pathogenetic role in juvenile myelomonocytic leukaemia (JMML), a rare myelodyplastic/myeloproliferative neoplasm occurring in children. Recently, mutations in ASXL1 were identified in chronic myelomonocytic leukaemia and other myeloid malignancies. We sequenced exon 12 of ASLX1 in 49 JMML patients, and found 2 novel heterozygous (nonsense and frameshift) mutations, one occurring as a sole lesion, the other was in conjunction with a PTPN11 mutation. ASXL1 cooperates with KDM1A in transcriptional repression and thereby ASXL1 mutations may synergize with or mimic other JMML-related mutations. [ABSTRACT FROM AUTHOR]

Background aims Monitoring cellular immune responses is one prerequisite for the rational development of cancer vaccines. Methods We describe an extensive effort to optimize and validate quantitatively an in vitro T-cell culture method by determining the phenotype and function of both CD4+ and CD8+ T cells, including measurement of the phenotype markers CCR7, CD45RA, CD28 and CD27 and the functional markers interferon (IFN)-γ, interleukin (IL)-2, macrophage inflammatory protein (MIP)-1β, tumor necrosis factor (TNF)-αand CD107a. Results Autologous peripheral blood mononuclear cells (PBMC) were potent stimulators that expanded antigen (Ag)-specific CD8+ T cells during short-term culture with the addition of IL-2 and IL-15 cytokines. Polyfunctional Ag-specific CD4+ and CD8+ T cells were detectable using this method. Conclusions Our culture system represents a robust human T-cell culture protocol that permits phenotypic, quantitative and qualitative evaluation of vaccine-induced CD4+ and CD8+ T-cell responses. [ABSTRACT FROM AUTHOR]

Blockade of inhibitory signals mediated by cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) has been shown to enhance T cell responses and induce durable clinical responses in patients with metastatic melanoma. The functional impact of anti-CTLA-4 therapy on human immune responses is still unclear. To explore this, we analyzed immune-related adverse events and immune responses in metastatic melanoma patients treated with ipilimumab, a fully human anti-CTLA-4 monoclonal antibody. Fifteen patients were selected on the basis of availability of suitable specimens for immunologic monitoring, and eight of these showed evidence of clinical benefit. Five of the eight patients with evidence of clinical benefit had NY-ESO-1 antibody, whereas none of seven clinical non-responders was seropositive for NY-ESO-1. All five NY-ESO-1 seropositive patients had clearly detectable CD4+ and CD8+ T cells against NY-ESO-1 following treatment with ipilimumab. One NY-ESO-1 seronegative clinical responder also had a NY-ESO-1 CD4+ and CD8+ T cell response, possibly related to prior vaccination with NY-ESO-1. Among five clinical non-responders analyzed, only one had a NY-ESO-1 CD4+ T cell response and this patient did not have detectable anti-NY-ESO-1 antibody. Overall, NY-ESO-1-specific T cell responses increased in frequency and functionality during anti-CTLA-4 treatment, revealing a polyfunctional response pattern of IFN-γ, MIP-1β and TNF-α. We therefore suggest that CTLA-4 blockade enhanced NY-ESO-1 antigen-specific B cell and T cell immune responses in patients with durable objective clinical responses and stable disease. These data provide an immunologic rationale for the efficacy of anti-CTLA-4 therapy and call for immunotherapeutic designs that combine NY-ESO-1 vaccination with CTLA-4 blockade. [ABSTRACT FROM AUTHOR]