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Antibodies are now recognized as key therapeutic tools to combat most forms of malignancy. Although the first wave of therapeutic antibodies that emerged over two decades ago directly target tumor cells for killing, a new class of antibody therapies targeting immunoregulatory pathways to boost antitumor immune responses by activating the immune system is poised for clinical success. A notable common characteristic of both classes of therapeutic antibodies is the importance of the IgG Fc domain, which connects the fine specificity of an antibody with immune cells that mediate antibody-triggered effector functions through their engagement of Fc receptor (FcR) family members. It is now clear that multiple variables, including the nature of the target molecules, the local presence of effector cells, and the expression patterns of FcRs, will dictate whether and how an antibody will necessitate interactions with FcRs to mediate optimal therapeutic effects. Thus, through careful in vivo mechanistic analyses of individual therapeutic antibodies, Fc domains engineered for optimal engagement of the appropriate cellular FcRs must be designed to maximize clinical success. (C) 2015 AACR.

MYC2 is an important regulator for jasmonic acid (JA) signaling, but little is known about its posttranslational regulation. Here, we show that the MYC2 C-terminal region interacted with the PLANT U-BOX PROTEIN10 (PUB10) armadillo repeats in vitro. MYC2 was efficiently polyubiquitinated by PUB10 with UBC8 as an E2 enzyme and the conserved C249 in PUB10 was required for activity. The inactive PUB10(C249A) mutant protein retained its ability to heterodimerize with PUB10, thus blocking PUB10 E3 activity as a dominant-negative mutant. Both MYC2 and PUB10 were nucleus localized and coimmunoprecipitation experiments confirmed their interaction in vivo. Although unstable in the wild type, MYC2 stability was enhanced in pub10, suggesting destabilization by PUB10. Moreover, MYC2 half-life was shortened or prolonged by induced expression of PUB10 or the dominant-negative PUB10(C249A) mutant, respectively. Root growth of pub10 seedlings phenocopied 35S:MYC2 seedlings and was hypersensitive to methyl jasmonate, whereas 35S: PUB10 and jin1-9 (myc2) seedlings were hyposensitive. In addition, the root phenotype conferred by MYC2 overexpression in double transgenic plants was reversed or enhanced by induced expression of PUB10 or PUB10(C249A), respectively. Similar results were obtained with three other JA-regulated genes, TAT, JR2, and PDF1.2. Collectively, our results show that MYC2 is targeted by PUB10 for degradation during JA responses.

Background: IL-23 is associated with plaque psoriasis susceptibility and pathogenesis. BI 655066 is a fully human IgG(1) mAb specific for the IL-23 p19 subunit. Objective: This first-in-human proof-of-concept study evaluated the clinical and biological effects of BI 655066 in patients with moderate-to-severe plaque psoriasis. Methods: We performed a single-rising-dose, multicenter, randomized, double-blind, placebo-controlled, within-dose cohort phase I trial. Patients received 0.01, 0.05, 0.25, 1, 3, or 5 mg/kg BI 655066 intravenously, 0.25 or 1 mg/kg BI 655066 subcutaneously, or matched placebo. The primary objective was safety evaluation. Results: Thirty-nine patients received single-dose BI 655066 intravenously (n = 18) or subcutaneously (n = 13) or placebo (n = 8). Adverse events were reported with similar frequency in the BI 655066 and placebo groups. Four serious adverse events (not considered treatment related) were reported among BI 655066-treated patients. BI 655066 was associated with clinical improvement from week 2 and maintained for up to 66 weeks after treatment. At week 12, 75%, 90%, and 100% decreases in the Psoriasis Area and Severity Index were achieved by 87%, 58%, and 16% of BI 655066-treated patients (any dose), respectively, versus none receiving placebo. BI 655066 treatment resulted in reduced expression of lesional skin genes associated with IL-23/IL-17 signaling pathways and normalization of psoriatic lesion gene expression profiles to a profile approaching that of nonlesional skin. Significant correlation between treatment-associated molecular changes and psoriasis area and severity index improvement was observed (r = 0.73, P = 2 x 10(-6)). Conclusions: BI 655066 was well tolerated and associated with rapid, substantial, and durable clinical improvement in patients with moderate-to-severe psoriasis, supporting a central role for IL-23 in psoriasis pathogenesis.

In this study we set out to explain the differing effects of parabiosis with genetically diabetic (db) mice versus administration of recombinant leptin. Parabiosis of db mutant, which overexpress leptin, to wildtype (WT) or genetically obese (ob) mice has been reported to cause death by starvation, whereas leptin infusions do not produce lethality at any dose or mode of delivery tested. Leptin is not post-translationally modified other than a single disulphide bond, raising the possibility that it might require additional factor(s) to exert the maximal appetite-suppressing effect. We reconfirmed the lethal effect of parabiosis of db mutant on WT mice and further showed that this lethality could not be rescued by administration of ghrelin or growth hormone. We then initiated a biochemical fractionation of a high-molecular-weight leptin complex from human plasma and identified clusterin as a major component of this leptin-containing complex. However, in contrast to previous reports, we failed to observe a leptin-potentiating effect of either exogenous or endogenous clusterin, and parabiosis of db clusterin(-/-) double-mutant to WT mice still caused lethality. Intriguingly, in parabiotic pairs of two WT mice, leptin infusion into one of the mice led to an enhanced starvation response during calorie restriction as evidenced by increased plasma ghrelin and growth-hormone levels. Moreover, leptin treatment resulted in death of the parabiotic pairs. These data suggest that the appetite suppression in WT mice after parabiosis to db mutants is the result of induced hyperleptinemia combined with the stress or other aspect(s) of the parabiosis procedure.

Transport networks play a key role across four realms of eukaryotic life: slime molds, fungi, plants, and animals. In addition to the developmental algorithms that build them, many also employ adaptive strategies to respond to stimuli, damage, and other environmental changes. We model these adapting network architectures using a generic dynamical system on weighted graphs and find in simulation that these networks ultimately develop a hierarchical organization of the final weighted architecture accompanied by the formation of a system-spanning backbone. In addition, we find that the long term equilibration dynamics exhibit behavior reminiscent of glassy systems characterized by long periods of slow changes punctuated by bursts of reorganization events.

test0310:Measurements of diffractive dissociation cross sections in pp collisions at root s = 7 TeV are presented in kinematic regions defined by the masses M-X and M-Y of the two final-state hadronic systems separated by the largest rapidity gap in the event. Differential cross sections are measured as a function of xi= M-X(2)/s in the region -5.5 < log(10)xi 10(X) < -2.5, for logio M-Y < 0.5, dominated by single dissociation (SD), and 0.5 < log(10)M(Y) < 1.1, dominated by double dissociation (DD), where M-x and M-y are given in GeV. The inclusive pp cross section is also measured as a function of the width of the central pseudorapidity gap Delta eta for Delta eta > 3, logio M-X > 1.1, and logioMy > 1.1, a region dominated by DD. The cross sections integrated over these regions are found to be, respectively, 2.99 0.02(staf)12392(sysf) mb, 1.18 +/- 0.02(stat) +/- 0.13(syst) mh, and 0.58 +/- 0.01(stat)(-0.11)(+0.13) (syst) mh, and are used to extract extrapolated total SD and DD cross sections. In addition, the inclusive differential cross section, d sigma/d Delta eta(F), for events with a pseudorapidity gap adjacent to the edge of the detector, is measured over Delta eta F = 8.4 units of pseudorapidity. The results are compared to those of other experiments and to theoretical predictions and found compatible with slowly 'rising diffractive cross sections as a function of center-of-mass energy.

Results are reported of a general search for pair production of heavy resonances decaying to pairs of hadronic jets in events with at least four jets. The study is based on up to 19.4 fb(-1) of integrated luminosity from proton-proton collisions at a center-of-mass energy of 8 TeV, recorded with the CMS detector at the LHC. Limits are determined on the production of scalar top quarks (top squarks) in the framework of R-parity violating supersymmetry and on the production of color-octet vector bosons (colorons). First limits at the LHC are placed on top squark production for two scenarios. The first assumes decay to a bottom quark and a light-flavor quark and is excluded for masses between 200 and 385 GeV, and the second assumes decay to a pair of light-flavor quarks and is excluded for masses between 200 and 350 GeV at 95% confidence level. Previous limits on colorons decaying to light-flavor quarks are extended to exclude masses from 200 to 835 GeV. (C) 2015 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license.

Adenylate kinases (AKs) are phosphotransferases that regulate the cellular adenine nucleotide composition and play a critical role in the energy homeostasis of all tissues. The AK2 isoenzyme is expressed in the mitochondrial intermembrane space and is mutated in reticular dysgenesis (RD), a rare form of severe combined immunodeficiency (SCID) in humans. RD is characterized by a maturation arrest in the myeloid and lymphoid lineages, leading to early onset, recurrent, and overwhelming infections. To gain insight into the pathophysiology of RD, we studied the effects of AK2 deficiency using the zebrafish model and induced pluripotent stem cells (iPSCs) derived from fibroblasts of an RD patient. In zebrafish, Ak2 deficiency affected hematopoietic stem and progenitor cell (HSPC) development with increased oxidative stress and apoptosis. AK2-deficient iPSCs recapitulated the characteristic myeloid maturation arrest at the promyelocyte stage and demonstrated an increased AMP/ADP ratio, indicative of an energy-depleted adenine nucleotide profile. Antioxidant treatment rescued the hematopoietic phenotypes in vivo in ak2 mutant zebrafish and restored differentiation of AK2-deficient iPSCs into mature granulocytes. Our results link hematopoietic cell fate in AK2 deficiency to cellular energy depletion and increased oxidative stress. This points to the potential use of antioxidants as a supportive therapeutic modality for patients with RD.

Deep dermatophytosis has been described in HIV and immunosuppressed patients. Recently, CARD9 (caspase recruitment domain-containing protein 9) deficiency has been reported in individuals with deep dermatophytosis previously classified as "immunocompetent". We report a 24-year-old Brazilian male patient with deep dermatophytosis born to an apparently non-consanguineous family. The symptoms started with oral candidiasis when he was 3 years old, persistent although treated. At 11 years old, well delimited, desquamative and pruriginous skin lesions appeared in the mandibular area; ketoconazole and itraconazole were introduced and maintained for 5 years. At 12 years of age, the lesions, which initially affected the face, started to spread to thoracic and back of the body (15 cm of diameter) and became ulcerative, secretive and painful. Terbinafine was introduced without any improvement. Trichophyton mentagrophytes was isolated from the skin lesions. A novel homozygous mutation in CARD9 (R101L) was identified in the patient, resulting in impaired neutrophil fungal killing. Both parents, one brother (with persistent superficial but not deep dermatophytosis) and one sister were heterozygous for this mutation, while another brother was found to be homozygous for the CARD9 wild-type allele. This is the first report of CARD9 deficiency in Latin America.

Histone modification and DNA methylation are associated with varying epigenetic "landscapes,''but detailed mechanistic and functional links between the two remain unclear. Using the ATRX-DNMT3-DNMT3L (ADD) domain of the DNA methyltransferase Dnmt3a as a paradigm, we apply protein engineering to dissect the molecular interactions underlying the recruitment of this enzyme to specific regions of chromatin in mouse embryonic stem cells (ESCs). By rendering the ADD domain insensitive to histone modification, specifically H3K4 methylation or H3T3 phosphorylation, we demonstrate the consequence of dysregulated Dnmt3a binding and activity. Targeting of a Dnmt3a mutant to H3K4me3 promoters decreases gene expression in a subset of developmental genes and alters ESC differentiation, whereas aberrant binding of another mutant to H3T3ph during mitosis promotes chromosome instability. Our studies support the general view that histone modification "reading'' and DNA methylation are closely coupled in mammalian cells, and suggest an avenue for the functional assessment of chromatin-associated proteins.