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Sarrafzadeh SA, Mahloojirad M, Nourizadeh M, Casanova JL, Pourpak Z, Bustamante J, Moin M
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Mendelian Susceptibility to Mycobacterial Disease due to IL-12R beta 1 Deficiency in Three Iranian Children

IRANIAN JOURNAL OF PUBLIC HEALTH 2016 MAR; 45(3):370-375
Mendelian susceptibility to mycobacterial diseases (MSMD) is a rare inheritance syndrome, characterized by a disseminated infection with mycobacterium in children following BCG vaccination at birth. Regarding the vaccination program in Iran, it may consider as a public health problem. The pathogenesis of MSMD is dependent on either insufficient production of IFN-gamma (gamma) or inadequate response to it. Here, we want to introduce three cases including two siblings and one girl from two unrelated families with severe mycobacterial infections referred to Immunology, Asthma and Allergy Research Institute (IAARI), from 2013 to 2015; their MSMD was confirmed by both cytokine assessment and genetic analysis. Regarding the clinical features of the patients, cell proliferation against a mitogen and BCG antigen was ordered in a lymphocyte transformation test (LTT) setting. ELISA was performed for the measurement of IL-12p70 and IFN-gamma in whole blood samples activated by BCG + recombinant human IFN-gamma and BCG + recombinant human IL-12, respectively. In contrast to mitogen, the antigen-dependent proliferation activity of the patients' leukocytes was significantly lower than that in normal range. We identified a homozygous mutation in IL12RB1 gene for two kindred who had a homozygous mutation affecting an essential splice site. For the third patient, a novel frameshift deletion in IL12RB1 gene was found. The genetic study results confirmed the impaired function of stimulated lymphocytes to release IFN-gamma following stimulation with BCG+IL-12 while the response to rhIFN-gamma for IL-12p70 production was relatively intact. Our findings show that cellular and molecular assessments are needed for precise identification of immunodeficiency disorders especially those without clear-cut diagnostic criteria.
Morgand M, Bouvin-Pley M, Plantier JC, Moreau A, Alessandri E, Simon F, Pace CS, Pancera M, Ho DD, Poignard P, Bjorkman PJ, Mouquet H, Nussenzweig MC, Kwong PD, Baty D, Chames P, Braibant M, Barin F
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V1/V2 Neutralizing Epitope is Conserved in Divergent Non-M Groups of HIV-1

JAIDS-JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES 2016 MAR 1; 71(3):237-245
Background: Highly potent broadly neutralizing monoclonal antibodies (bNAbs) have been obtained from individuals infected by HIV-1 group M variants. We analyzed the cross-group neutralization potency of these bNAbs toward non-M primary isolates (PI). Material and Methods: The sensitivity to neutralization was analyzed in a neutralization assay using TZM-bl cells. Twenty-three bNAbs were used, including reagents targeting the CD4-binding site, the N160 glycan-V1/V2 site, the N332 glycan-V3 site, the membrane proximal external region of gp41, and complex epitopes spanning both env subunits. Two bispecific antibodies that combine the inhibitory activity of an anti-CD4 with that of PG9 or PG16 bNAbs were included in the study (PG9-iMab and PG16-iMab). Results: Cross-group neutralization was observed only with the bNAbs targeting the N160 glycan-V1/V2 site. Four group O PIs, 1 group N PI, and the group P PI were neutralized by PG9 and/or PG16 or PGT145 at low concentrations (0.04-9.39 mu g/mL). None of the non-M PIs was neutralized by the bNAbs targeting other regions at the highest concentration tested, except 10E8 that neutralized weakly 2 group N PIs and 35O22 that neutralized 1 group O PI. The bispecific bNAbs neutralized very efficiently all the non-M PIs with IC50 below 1 mu g/mL, except 2 group O strains. Conclusion: The N160 glycan-V1/V2 site is the most conserved neutralizing site within the 4 groups of HIV-1. This makes it an interesting target for the development of HIV vaccine immunogens. The corresponding bNAbs may be useful for immunotherapeutic strategies in patients infected by non-M variants.
Gleicher N, Kushnir VA, Barad DH
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Randomized controlled trial of minimal stimulation versus conventional in vitro fertilization

AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY 2016 MAR; 214(3):412-413
Shen Y, Barros M, Vennemann T, Gallagher DT, Yin Y, Linden SB, Heselpoth RD, Spencer DJ, Donovan DM, Moult J, Fischetti VA, Heinrich F, Losche M, Nelson DC
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A bacteriophage endolysin that eliminates intracellular streptococci

ELIFE 2016 MAR 15; 5(?):? Article e13152
PIyC, a bacteriophage-encoded endolysin, lyses Streptococcus pyogenes (Spy) on contact. Here, we demonstrate that PIyC is a potent agent for controlling intracellular Spy that often underlies refractory infections. We show that the PIyC holoenzyme, mediated by its PIyCB subunit, crosses epithelial cell membranes and clears intracellular Spy in a dose-dependent manner. Quantitative studies using model membranes establish that PIyCB interacts strongly with phosphatidylserine (PS), whereas its interaction with other lipids is weak, suggesting specificity for PS as its cellular receptor. Neutron reflection further substantiates that PIyC penetrates bilayers above a PS threshold concentration. Crystallography and docking studies identify key residues that mediate PIyCB PS interactions, which are validated by site-directed mutagenesis. This is the first report that a native endolysin can traverse epithelial membranes, thus substantiating the potential of PIyC as an antimicrobial for Spy in the extracellular and intracellular milieu and as a scaffold for engineering other functionalities.
Schwantes-An TH, Zhang J, Chen LS, Hartz SM, Culverhouse RC, Chen XN, Coon H, Frank J, Kamens HM, Konte B, Kovanen L, Latvala A, Legrand LN, Maher BS, Melroy WE, Nelson EC, Reid MW, Robinson JD, Shen PH, Yang BZ, Andrews JA, Aveyard P, Beltcheva O, Brown SA, Cannon DS, Cichon S, Corley RP, Dahmen N, Degenhardt L, Foroud T, Gaebel W, Giegling I, Glatt SJ, Grucza RA, Hardin J, Hartmann AM, Heath AC, Herms S, Hodgkinson CA, Hoffmann P, Hops H, Huizinga D, Ising M, Johnson EO, Johnstone E, Kaneva RP, Kendler KS, Kiefer F, Kranzler HR, Krauter KS, Levran O, Lucae S, Lynskey MT, Maier W, Mann K, Martin NG, Mattheisen M, Montgomery GW, Muller-Myhsok B, Murphy MF, Neale MC, Nikolov MA, Nishita D, Nothen MM, Nurnberger J, Partonen T, Pergadia ML, Reynolds M, Ridinger M, Rose RJ, Rouvinen-Lagerstrom N, Scherbaum N, Schmal C, Soyka M, Stallings MC, Steffens M, Treutlein J, Tsuang M, Wall TL, Wodarz N, Yuferov V, Zill P, Bergen AW, Chen JC, Cinciripini PM, Edenberg HJ, Ehringer MA, Ferrell RE, Gelernter J, Goldman D, Hewitt JK, Hopfer CJ, Iacono WG, Kaprio J, Kreek MJ, Kremensky IM, Madden PAF, McGue M, Munafo MR, Philibert RA, Rietschel M, Roy A, Rujescu D, Saarikoski ST, Swan GE, Todorov AA, Vanyukov MM, Weiss RB, Bierut LJ, Saccone NL
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Association of the OPRM1 Variant rs1799971 (A118G) with Non-Specific Liability to Substance Dependence in a Collaborative de novo Meta-Analysis of European-Ancestry Cohorts

BEHAVIOR GENETICS 2016 MAR; 46(2):151-169
The mu1 opioid receptor gene, OPRM1, has long been a high-priority candidate for human genetic studies of addiction. Because of its potential functional significance, the non-synonymous variant rs1799971 (A118G, Asn40Asp) in OPRM1 has been extensively studied, yet its role in addiction has remained unclear, with conflicting association findings. To resolve the question of what effect, if any, rs1799971 has on substance dependence risk, we conducted collaborative meta-analyses of 25 datasets with over 28,000 European-ancestry subjects. We investigated non-specific risk for "general" substance dependence, comparing cases dependent on any substance to controls who were non-dependent on all assessed substances. We also examined five specific substance dependence diagnoses: DSM-IV alcohol, opioid, cannabis, and cocaine dependence, and nicotine dependence defined by the proxy of heavy/light smoking (cigarettes-per-day > 20 vs. a parts per thousand currency sign10). The G allele showed a modest protective effect on general substance dependence (OR = 0.90, 95 % C.I. [0.83-0.97], p value = 0.0095, N = 16,908). We observed similar effects for each individual substance, although these were not statistically significant, likely because of reduced sample sizes. We conclude that rs1799971 contributes to mechanisms of addiction liability that are shared across different addictive substances. This project highlights the benefits of examining addictive behaviors collectively and the power of collaborative data sharing and meta-analyses.
Scharf L, West AP, Sievers SA, Chen C, Jiang S, Gao H, Gray MD, McGuire AT, Scheid JF, Nussenzweig MC, Stamatatos L, Bjorkman PJ
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Structural basis for germline antibody recognition of HIV-1 immunogens

ELIFE 2016 MAR 21; 5(?):? Article e13783
Efforts to elicit broadly neutralizing antibodies (bNAbs) against HIV-1 require understanding germline bNAb recognition of HIV-1 envelope glycoprotein (Env). The VRC01-class bNAb family derived from the VH1-2(star)02 germline allele arose in multiple HIV-1 infected donors, yet targets the CD4-binding site on Env with common interactions. Modified forms of the 426c Env that activate germline-reverted B cell receptors are candidate immunogens for eliciting VRC01-class bNAbs. We present structures of germline-reverted VRC01-class bNAbs alone and complexed with 426c-based gp120 immunogens. Germline bNAb-426c gp120 complexes showed preservation of VRC01-class signature residues and gp120 contacts, but detectably different binding modes compared to mature bNAb-gp120 complexes. Unlike typical antibody-antigen interactions, VRC01 -class germline antibodies exhibited preformed antigen-binding conformations for recognizing immunogens. Affinity maturation introduced substitutions increasing induced-fit recognition and electropositivity, potentially to accommodate negatively-charged complex-type N-glycans on gp120. These results provide general principles relevant to the unusual evolution of VRC01-class bNAbs and guidelines for structure-based immunogen design.
Wagh K, Bhattacharya T, Williamson C, Robles A, Bayne M, Garrity J, Rist M, Rademeyer C, Yoon H, Lapedes A, Gao HM, Greene K, Louder MK, Kong R, Karim SA, Burton DR, Barouch DH, Nussenzweig MC, Mascola JR, Morris L, Montefiori DC, Korber B, Seaman MS
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Optimal Combinations of Broadly Neutralizing Antibodies for Prevention and Treatment of HIV-1 Clade C

PLOS PATHOGENS 2016 MAR; 12(3):? Article e1005520
The identification of a new generation of potent broadly neutralizing HIV-1 antibodies (bnAbs) has generated substantial interest in their potential use for the prevention and/or treatment of HIV-1 infection. While combinations of bnAbs targeting distinct epitopes on the viral envelope (Env) will likely be required to overcome the extraordinary diversity of HIV-1, a key outstanding question is which bnAbs, and how many, will be needed to achieve optimal clinical benefit. We assessed the neutralizing activity of 15 bnAbs targeting four distinct epitopes of Env, including the CD4-binding site (CD4bs), the V1/V2-glycan region, the V3-glycan region, and the gp41 membrane proximal external region (MPER), against a panel of 200 acute/early clade C HIV-1 Env pseudoviruses. A mathematical model was developed that predicted neutralization by a subset of experimentally evaluated bnAb combinations with high accuracy. Using this model, we performed a comprehensive and systematic comparison of the predicted neutralizing activity of over 1,600 possible double, triple, and quadruple bnAb combinations. The most promising bnAb combinations were identified based not only on breadth and potency of neutralization, but also other relevant measures, such as the extent of complete neutralization and instantaneous inhibitory potential (IIP). By this set of criteria, triple and quadruple combinations of bnAbs were identified that were significantly more effective than the best double combinations, and further improved the probability of having multiple bnAbs simultaneously active against a given virus, a requirement that may be critical for countering escape in vivo. These results provide a rationale for advancing bnAb combinations with the best in vitro predictors of success into clinical trials for both the prevention and treatment of HIV-1 infection.
Halberg N, Sengelaub CA, Navrazhina K, Molina H, Uryu K, Tavazoie SF
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PITPNC1 Recruits RAB1B to the Golgi Network to Drive Malignant Secretion

CANCER CELL 2016 MAR 14; 29(3):339-353
Enhanced secretion of tumorigenic effector proteins is a feature of malignant cells. The molecular mechanisms underlying this feature are poorly defined. We identify PITPNC1 as a gene amplified in a large fraction of human breast cancer and overexpressed in metastatic breast, melanoma, and colon cancers. Biochemical, molecular, and cell-biological studies reveal that PITPNC1 promotes malignant secretion by binding Golgi-resident PI4P and localizing RAB1B to the Golgi. RAB1B localization to the Golgi allows for the recruitment of GOLPH3, which facilitates Golgi extension and enhanced vesicular release. PITPNC1-mediated vesicular release drives metastasis by increasing the secretion of pro-invasive and pro-angiogenic mediators HTRA1, MMP1, FAM3C, PDGFA, and ADAM10. We establish PITPNC1 as a PI4P-binding protein that enhances vesicular secretion capacity in malignancy.
Hart T, Xie L
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Providing data science support for systems pharmacology and its implications to drug discovery

EXPERT OPINION ON DRUG DISCOVERY 2016 MAR 3; 11(3):241-256
Introduction: The conventional one-drug-one-target-one-disease drug discovery process has been less successful in tracking multi-genic, multi-faceted complex diseases. Systems pharmacology has emerged as a new discipline to tackle the current challenges in drug discovery. The goal of systems pharmacology is to transform huge, heterogeneous, and dynamic biological and clinical data into interpretable and actionable mechanistic models for decision making in drug discovery and patient treatment. Thus, big data technology and data science will play an essential role in systems pharmacology. Areas covered: This paper critically reviews the impact of three fundamental concepts of data science on systems pharmacology: similarity inference, overfitting avoidance, and disentangling causality from correlation. The authors then discuss recent advances and future directions in applying the three concepts of data science to drug discovery, with a focus on proteome-wide context-specific quantitative drug target deconvolution and personalized adverse drug reaction prediction. Expert opinion: Data science will facilitate reducing the complexity of systems pharmacology modeling, detecting hidden correlations between complex data sets, and distinguishing causation from correlation. The power of data science can only be fully realized when integrated with mechanism-based multi-scale modeling that explicitly takes into account the hierarchical organization of biological systems from nucleic acid to proteins, to molecular interaction networks, to cells, to tissues, to patients, and to populations.
Zhu N, Chen M, Eng R, DeJong J, Sinha AU, Rahnamay NF, Roche R, Al-Shahrour F, Minehart JC, Chen CW, Deshpande AJ, Xu HM, Chu SHH, Ebert BL, Roeder RG, Armstrong SA
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MLL-AF9-and HOXA9-mediated acute myeloid leukemia stem cell self-renewal requires JMJD1C

JOURNAL OF CLINICAL INVESTIGATION 2016 MAR; 126(3):997-1011
Self-renewal is a hallmark of both hematopoietic stem cells (HSCs) and leukemia stem cells (LSCs); therefore, the identification of mechanisms that are required for LSC, but not HSC, function could provide therapeutic opportunities that are more effective and less toxic than current treatments. Here, we employed an in vivo shRNA screen and identified jumonji domain-containing protein JMJD1C as an important driver of MLL-AF9 leukemia. Using a conditional mouse model, we showed that loss of JMJD1C substantially decreased LSC frequency and caused differentiation of MLL-AF9- and homeobox A9-driven (HOXA9-driven) leukemias. We determined that JMJU1C directly interacts with HOXA9 and modulates a HOXA9-controlled gene-expression program. In contrast, loss of JMJD1C led to only minor defects in blood homeostasis and modest effects on HSC self-renewal. Together, these data establish JMJD1C as an important mediator of MLL-AF9- and HOXA9-driven LSC function that is largely dispensable for HSC function.