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Phase III+: The University is open for expanded research operations; only authorized personnel will be admitted on campus. More info here.
Phase III+: The University is open for expanded research operations; only authorized personnel will be admitted on campus. More info here.
Phase III+: The University is open for expanded research operations; only authorized personnel will be admitted on campus. More info here.

Publications search

Found 36968 matches. Displaying 21-30
Chen SS, Vedula RS, Cuevas-Navarro A, Lu B, Hogg SJ, Wang ER, Benbarche S, Knorr K, Kim WJ, Stanley RF, Cho HA, Erickson C, Singer M, Cui D, Tittley S, Durham BH, Pavletich TS, Fiala E, Walsh MF, Inoue D, Monette S, Taylor J, Rosen N, McCormick F, Lindsley RC, Castel P, Abdel-Wahab O
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Impaired Proteolysis of Noncanonical RAS Proteins Drives Clonal Hematopoietic Transformation

CANCER DISCOVERY 2022 OCT; 12(10):2434-2453
Recently, screens for mediators of resistance to FLT3 and ABL kinase inhibitors in leukemia resulted in the discovery of LZTR1 as an adapter of a Cullin-3 RING E3 ubiquitin ligase complex responsible for the degradation of RAS GTPases. In parallel, dysregulated LZTR1 expression via aberrant splicing and mutations was identifi ed in clonal hematopoietic condi-tions. Here we identify that loss of LZTR1, or leukemia-associated mutants in the LZTR1 substrate and RAS GTPase RIT1 that escape degradation, drives hematopoietic stem cell (HSC) expansion and leuke-mia in vivo . Although RIT1 stabilization was suffi cient to drive hematopoietic transformation, transfor-mation mediated by LZTR1 loss required MRAS. Proteolysis targeting chimeras (PROTAC) against RAS or reduction of GTP-loaded RAS overcomes LZTR1 loss-mediated resistance to FLT3 inhibitors. These data reveal proteolysis of noncanonical RAS proteins as novel regulators of HSC self-renewal, defi ne the function of RIT1 and LZTR1 mutations in leukemia, and identify means to overcome drug resistance due to LZTR1 downregulation.SIGNIFICANCE: Here we identify that impairing proteolysis of the noncanonical RAS GTPases RIT1 and MRAS via LZTR1 downregulation or leukemia-associated mutations stabilizing RIT1 enhances MAP kinase activation and drives leukemogenesis. Reducing the abundance of GTP-bound KRAS and NRAS overcomes the resistance to FLT3 kinase inhibitors associated with LZTR1 downregulation in leukemia.
Gaddis N, Mathur R, Marks J, Zhou LR, Quach B, Waldrop A, Levran O, Agrawal A, Randesi M, Adelson M, Jeffries PW, Martin NG, Degenhardt L, Montgomery GW, Wetherill L, Lai DB, Bucholz K, Foroud T, Porjesz B, Runarsdottir V, Tyrfingsson T, Einarsson G, Gudbjartsson DF, Webb BT, Crist RC, Kranzler HR, Sherva R, Zhou H, Hulse G, Wildenauer D, Kelty E, Attia J, Holliday EG, McEvoy M, Scott RJ, Schwab SG, Maher BS, Gruza R, Kreek MJ, Nelson EC, Thorgeirsson T, Stefansson K, Berrettini WH, Gelernter J, Edenberg HJ, Bierut L, Hancock DB, Johnson EO
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Multi-trait genome-wide association study of opioid addiction: OPRM1 and beyond

SCIENTIFIC REPORTS 2022 OCT 7; 12(1):? Article 16873
Opioid addiction (OA) is moderately heritable, yet only rs1799971, the A118G variant in OPRM1, has been identified as a genome-wide significant association with OA and independently replicated. We applied genomic structural equation modeling to conduct a GWAS of the new Genetics of Opioid Addiction Consortium (GENOA) data together with published studies (Psychiatric Genomics Consortium, Million Veteran Program, and Partners Health), comprising 23,367 cases and effective sample size of 88,114 individuals of European ancestry. Genetic correlations among the various OA phenotypes were uniformly high (r(g) > 0.9). We observed the strongest evidence to date for OPRM1: lead SNP rs9478500 (p = 2.56 x 10(-9)). Gene-based analyses identified novel genome-wide significant associations with PPP6C and FURIN. Variants within these loci appear to be pleiotropic for addiction and related traits.
Nam AS, Dusaj N, Izzo F, Murali R, Myers RM, Mouhieddine TH, Sotelo J, Benbarche S, Waarts M, Gaiti F, Tahris S, Levine R, Abdel-Wahab O, Godley LA, Chaligne R, Ghobrial I, Landau DA
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Single-cell multi-omics of human clonal hematopoiesis reveals that DNMT3A R882 mutations perturb early progenitor states through selective hypomethylation

NATURE GENETICS 2022 OCT; 54(10):1514-+
Somatic mutations in cancer genes have been detected in clonal expansions across healthy human tissue, including in clonal hematopoiesis. However, because mutated and wild-type cells are admixed, we have limited ability to link genotypes with phenotypes. To overcome this limitation, we leveraged multi-modality single-cell sequencing, capturing genotype, transcriptomes and methylomes in progenitors from individuals with DNMT3A R882 mutated clonal hematopoiesis. DNMT3A mutations result in myeloid over lymphoid bias, and an expansion of immature myeloid progenitors primed toward megakaryocytic-erythroid fate, with dysregulated expression of lineage and leukemia stem cell markers. Mutated DNMT3A leads to preferential hypomethylation of polycomb repressive complex 2 targets and a specific CpG flanking motif. Notably, the hypomethylation motif is enriched in binding motifs of key hematopoietic transcription factors, serving as a potential mechanistic link between DNMT3A mutations and aberrant transcriptional phenotypes. Thus, single-cell multi-omics paves the road to defining the downstream consequences of mutations that drive clonal mosaicism. Multi-modality single-cell sequencing determines genotype, transcriptome and methylome information in cells from individuals with DNMT3A R882 mutated clonal hematopoiesis, allowing for the comparison of mutant and wild-type cells from the same individuals.
Palillo JA, Mollenkopf D, Marsh AE, Wittum TE, James JPB, Reichley SR, Ghosh S, Palillo MB, Malbrue R
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Detection of Zoonotic Bacteria and Paragonimus kellicotti in Red Swamp Crayfish (Procambarus clarkii) and the Assessment of Traditional Crayfish Boils

JOURNAL OF FOOD PROTECTION 2022 OCT; 85(10):1388-1396
Studies of red swamp crayfish (Procambarus clarkii) outside of the United States confirm the presence of a variety of zoonotic pathogens, but it is unknown whether these same pathogens occur in P. clarkii in the United States. The U.S. commercial crayfish industry generates $200 million yearly, underscoring the need to evaluate this consumer commodity. The study objectives were to evaluate specific zoonotic pathogens present on P. clarkii from Alabama and Louisiana, states in the southeastern United States, and to determine the effectiveness of traditional food preparation methods to reduce pathogens. Experiment A evaluated the presence of Escherichia coli, Salmonella, Staphylococcus aureus, and Vibrio spp. in crayfish and environmental samples over a 2-month collection period (May to June 2021). Crayfish sampling consisted of swabbing the cephalothorax region; 15 samples were tested for E. coli, Salmonella, and S. aureus, and an additional 15 samples for Vibrio spp. Additionally, crayfish shipping materials were sampled. In experiment B, 92 crayfish were evaluated for Paragonimus kellicotti. Experiment C compared live and boiled crayfish for the presence of Vibrio spp. In experiments A and B, all 60 (100%) crayfish samples and 13 (81.25%) of 16 environmental samples showed growth characteristic of Vibrio spp. Three (5%) of 60 samples showed E. coli growth, with no statistical difference (P = 0.5536) between farms. P. kellicotti, Salmonella, and S. aureus were not recovered from any samples. In experiment C, all 10 (100%) of the live preboiled crayfish samples showed characteristic growth, whereas 1 (10%) of 10 samples of crayfish boiled in unseasoned water showed Vibrio growth (P , 0.0001). These results confirm that Vibrio spp. and E. coli may be present on U.S. commercial crayfish and that care should be taken when handling any materials that come into contact with live crayfish because they can potentially be contaminated.
Kolbe L, Fins JJ
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Health Equity, History, and a New Presidential Bioethics Commission: Lessons from the "Lost" Reports

Convening a national bioethics commission has historically been one of the most powerful bioethical legacies a US presidential administration can undertake. The Biden Administration has not yet created such a commission; here we argue that centering health equity and healthcare access would provide a vital framework for a new commission's legacy. Moreover, we demonstrate two crucial historical episodes when American presidents appointed commissions to examine the practical and ethical implications of these very issues. We turn first to the 1952 President's Commission report on "Building America's Health," a lofty vision of universal healthcare access stymied by both political conflict and unaddressed problems of racism in the era's legislation. Its rich yet incomplete account of American health inequities serves as a valuable forerunner to questions of justice in bioethics. We then explore the President's Commission's 1983 report "Securing Access to Healthcare: A Report on the Ethical Implications of Differences in the Availability of Health Services." This report took up the mantle of equity in healthcare access, again with mixed results. Only by understanding the checkered history of these overlooked, practically "lost" reports can a new era in American bioethics successfully re-center the goal of equitable health for all.
Goncalves-Carneiro D, Mastrocola E, Lei X, DaSilva J, Chan YF, Bieniasz PD
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Rational attenuation of RNA viruses with zinc finger antiviral protein

NATURE MICROBIOLOGY 2022 OCT; 7(10):1558-+
Attenuation of a virulent virus is a proven approach for generating vaccines but can be unpredictable. For example, synonymous recoding of viral genomes can attenuate replication but sometimes results in pleiotropic effects that confound rational vaccine design. To enable specific, conditional attenuation of viruses, we examined target RNA features that enable zinc finger antiviral protein (ZAP) function. ZAP recognized CpG dinucleotides and targeted CpG-rich RNAs for depletion, but RNA features such as CpG numbers, spacing and surrounding nucleotide composition that enable specific modulation by ZAP were undefined. Using synonymously mutated HIV-1 genomes, we defined several sequence features that govern ZAP sensitivity and enable stable attenuation. We applied rules derived from experiments with HIV-1 to engineer a mutant enterovirus A71 genome whose attenuation was stable and strictly ZAP-dependent, both in cell culture and in mice. The conditionally attenuated enterovirus A71 mutant elicited neutralizing antibodies that were protective against wild-type enterovirus A71 infection and disease in mice. ZAP sensitivity can thus be readily applied for the rational design of conditionally attenuated viral vaccines. Rational design of live-attenuated RNA viruses with potential as vaccines is enabled by identification of sequence rules for zinc finger antiviral protein.
Yang N, Garcia A, Meyer C, Tuschl T, Merghoub T, Wolchok JD, Deng L
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Heat-inactivated modified vaccinia virus Ankara boosts Th1 cellular and humoral immunity as a vaccine adjuvant

NPJ VACCINES 2022 OCT 19; 7(1):? Article 120
Protein or peptide-based subunit vaccines have generated excitement and renewed interest in combating human cancer or COVID-19 outbreak. One major concern for subunit vaccine application is the weak immune responses induced by protein or peptides. Developing novel and effective vaccine adjuvants are critical for the success of subunit vaccines. Here we explored the potential of heat-inactivated MVA (heat-iMVA) as a vaccine adjuvant. Heat-iMVA dramatically enhances T cell responses and antibodies responses, mainly toward Th1 immune responses when combined with protein or peptide-based immunogen. The adjuvant effect of Heat-iMVA is stronger than live MVA and is dependent on the cGAS/STING-mediated cytosolic DNA-sensing pathway. In a therapeutic vaccination model based on tumor neoantigen peptide vaccine, Heat-iMVA significantly extended the survival and delayed tumor growth. When combined with SARS-CoV-2 spike protein, Heat-iMVA induced more robust spike-specific antibody production and more potent neutralization antibodies. Our results support that Heat-iMVA can be developed as a safe and potent vaccine adjuvant for subunit vaccines against cancer or SARS-CoV-2.
Singh PK, Chen ZL, Horn K, Norris EH
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Blocking domain 6 of high molecular weight kininogen to understand intrinsic clotting mechanisms

Background The contact system is initiated by factor (F) XII activation and the assembly of high molecular weight kininogen (HK) with either FXI or prekallikrein (PK) on a negatively charged surface. Overactivation of this system contributes to thrombosis and inflammation in numerous diseases. To develop effective therapeutics for contact system disorders, a detailed understanding of this pathway is needed. Methods We performed coagulation assays in normal human plasma and various factor-deficient plasmas. To evaluate how HK-mediated PK and FXI activation contributes to coagulation, we used an anti-HK antibody to block access to domain 6 of HK, the region required for efficient activation of PK and FXI. Results FXI's binding to HK and its subsequent activation by activated FXII contributes to coagulation. We found that the 3E8 anti-HK antibody can inhibit the binding of FXI or PK to HK, delaying clot formation in human plasma. Our data show that in the absence of FXI, however, PK can substitute for FXI in this process. Addition of activated FXI (FXIa) or activated PK (PKa) abolished the inhibitory effect of 3E8. Moreover, the requirement of HK in intrinsic coagulation can be largely bypassed by adding FXIa. Like FXIa, exogenous PKa shortened the clotting time in HK-deficient plasma, which was not due to feedback activation of FXII. Conclusions This study improves our understanding of HK-mediated coagulation and provides an explanation for the absence of bleeding in HK-deficient individuals. 3E8 specifically prevented HK-mediated FXI activation; therefore, it could be used to prevent contact activation-mediated thrombosis without altering hemostasis.
Gauhar Z, Tejwani L, Abdullah U, Saeed S, Shafique S, Badshah M, Choi J, Dong WL, Nelson-Williams C, Lifton RP, Lim J, Raja GK
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A Novel Missense Mutation in ERCC8 Co-Segregates with Cerebellar Ataxia in a Consanguineous Pakistani Family

CELLS 2022 OCT; 11(19):? Article 3090
Autosomal-recessive cerebellar ataxias (ARCAs) are heterogeneous rare disorders mainly affecting the cerebellum and manifest as movement disorders in children and young adults. To date, ARCA causing mutations have been identified in nearly 100 genes; however, they account for less than 50% of all cases. We studied a multiplex, consanguineous Pakistani family presenting with a slowly progressive gait ataxia, body imbalance, and dysarthria. Cerebellar atrophy was identified by magnetic resonance imaging of brain. Using whole exome sequencing, a novel homozygous missense mutation ERCC8:c.176T>C (p.M59T) was identified that co-segregated with the disease. Previous studies have identified homozygous mutations in ERCC8 as causal for Cockayne Syndrome type A (CSA), a UV light-sensitive syndrome, and several ARCAs. ERCC8 plays critical roles in the nucleotide excision repair complex. The p.M59T, a substitution mutation, is located in a highly conserved WD1 beta-transducin repeat motif. In silico modeling showed that the structure of this protein is significantly affected by the p.M59T mutation, likely impairing complex formation and protein-protein interactions. In cultured cells, the p.M59T mutation significantly lowered protein stability compared to wildtype ERCC8 protein. These findings expand the role of ERCC8 mutations in ARCAs and indicate that ERCC8-related mutations should be considered in the differential diagnosis of ARCAs.
Zhou PC
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Protein vaccine NVX-CoV2373 elicits functional T cell immunity

JOURNAL OF CLINICAL INVESTIGATION 2022 OCT 3; 132(19):? Article e163614
The SARS-CoV-2 vaccine NVX-CoV2373 is a protein-based vaccine that might circumvent the difficulties in distributing mRNA vaccines to regions with limited access to cold-chain and refrigeration. However, the NVX-CoV2373-induced T cell and antibody responses remain poorly understood. In this issue of the JCI, Moderbacher et al. characterized SARS-CoV-2-specific CD4(+) and CD8(+) T cell responses elicited by one or two doses of NVX-CoV2373 in individuals enrolled in a phase I/IIa trial. Substantially increased spike-specific CD4(+) and T follicular helper cells were found after the first or second vaccine dose, with some individuals developing a modest spike-specific CD8(+) T cell response. Correlation analysis revealed an association between spike-specific CD4(+) T cells and neutralizing antibody titers. Notably, preexisting T cell immunity showed negligible effects on NVX-CoV2373-induced T cell responses. These findings indicate that the protein-based vaccine NVX-CoV2373 induces robust T cell immunity capable of recognizing SARS-CoV-2 antigens and supporting humoral immune responses.