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Zhang Q, Casanova JL
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Human TET2 bridges cancer and immunity

BLOOD 2020 AUG 27; 136(9):1018-1019
In this issue of Blood, Stremenova Spegarova et al report 3 patients with biallelic loss-of-function (LOF) TET2 mutations.(1) These patients suffered from infections, autoimmunity, and lymphoma, demonstrating 3 of the 5 potential phenotypes seen in inborn errors of immunity. TET2 encodes ten-eleven translocation methylcytosine dioxygenase 2 (TET2), 1 of the 3 members of the TET family of epigenetic regulators responsible for converting 5-methylcytosine to 5-hydroxymethylcytosine (5hmC) and subsequent oxidation products in an active DNA demethylation pathway. TET2 is ubiquitous, with particularly strong expression in hematopoietic cells. Somatic LOF TET2 mutations were first reported in patients with myeloproliferative disorders and hematologic cancers over 10 years ago.(2) TET2 haploinsufficiency has also recently been reported in families with myeloid or lymphoid cancers. Intriguingly, some of these patients also presented signs of enhanced monocyte- and macrophage-mediated inflammatory responses, together with atherosclerotic plaque development, which has been associated with increases in NLRP3 inflammasome activation.(3,4) Thus, the tumor suppressor role of TET2 has been extensively documented, especially in myeloid lineages.
Barnes CO, West AP, Huey-Tubman KE, Hoffmann MAG, Sharaf NG, Hoffman PR, Koranda N, Gristick HB, Gaebler C, Muecksch F, Lorenzi JCC, Finkin S, Hagglof T, Hurley A, Millard KG, Weisblum Y, Schmidt F, Hatziioannou T, Bieniasz PD, Caskey M, Robbiani DF, Nussenzweig MC, Bjorkman PJ
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Structures of Human Antibodies Bound to SARS-CoV-2 Spike Reveal Common Epitopes and Recurrent Features of Antibodies

CELL 2020 AUG 20; 182(4):828-842.e16
Neutralizing antibody responses to coronaviruses mainly target the receptor-binding domain (RBD) of the trimeric spike. Here, we characterized polyclonal immunoglobulin Gs (IgGs) and Fabs from COVID-19 convalescent individuals for recognition of coronavirus spikes. Plasma IgGs differed in their focus on RBD epitopes, recognition of alpha- and beta-coronaviruses, and contributions of avidity to increased binding/neutralization of IgGs over Fabs. Using electron microscopy, we examined specificities of polyclonal plasma Fabs, revealing recognition of both S1(A) and RBD epitopes on SARS-CoV-2 spike. Moreover, a 3.4 A cryo-electron microscopy (cryo-EM) structure of a neutralizing monoclonal Fab-spike complex revealed an epitope that blocks ACE2 receptor binding. Modeling based on these structures suggested different potentials for inter-spike crosslinking by IgGs on viruses, and characterized IgGs would not be affected by identified SARS-CoV-2 spike mutations. Overall, our studies structurally define a recurrent anti-SARS-CoV-2 antibody class derived from VH3-53/VH3-66 and similarity to a SARS-CoV VH3-30 antibody, providing criteria for evaluating vaccine-elicited antibodies.
Valente PK, Wu YM, Cohen YZ, Caskey M, Meyers K
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Behavioral and social science research to support development of educational materials for clinical trials of broadly neutralizing antibodies for HIV treatment and prevention

CLINICAL TRIALS 2020 AUG 24; ?(?):? Article 1740774520948042
Background/Aims Early integration of behavioral and social sciences research into clinical trials can improve trial conduct and facilitate future implementation of biomedical interventions. We sought to examine participants' experiences in clinical trials with broadly neutralizing antibodies and describe the development of educational materials for use in future broadly neutralizing antibody research. Methods We conducted semi-structured interviews with trial participants in phase 1 trials evaluating safety and efficacy of broadly neutralizing antibodies for HIV prevention and treatment and key informants (i.e. trial staff involved in broadly neutralizing antibody research). Semi-structured interviews were transcribed and analyzed thematically. Based on findings from the interviews, we developed educational materials addressing concerns and misconceptions identified among trial participants with input from community and research stakeholders. Educational materials were used in subsequent clinical trials with broadly neutralizing antibodies. We evaluated trial staff's experiences with newly developed educational materials in follow-up key informant interviews. Results Although most participants were concerned about long-term harms related to the investigational product upon enrollment, absence of severe side effects in the trial led to an underestimation of risks related to the study during trial participation. Participants showed a poor understanding of what broadly neutralizing antibodies are and the differences between broadly neutralizing antibodies and other HIV prevention and treatment products, such as antiretrovirals. Many trial participants overestimated the possible public health impact of the broadly neutralizing antibody trials in which they were enrolled, associating broadly neutralizing antibody research with the development of vaccine or cure for HIV in the near future. Based on these concerns and misconceptions among trial participants, we developed a frequently asked questions document and adapted an existing educational video about broadly neutralizing antibodies. In follow-up interviews, key informants reported that materials helped address trial participants' concerns and questions related to the trial. Key informants reported using the educational materials not only during informed consent but also throughout trial participation, which contributed to making informed consent an "ongoing" process. Conclusion Integration of behavioral research into clinical trials with broadly neutralizing antibodies is key to identify and address key concerns among trial participants. Behavioral and social sciences research promotes communication between trial participants and biomedical researchers, facilitates engagement of participants and trial staff, and strengthens trial conduct. Development of educational materials collaboratively by behavioral and clinical scientists, trial staff, and community stakeholders is feasible and may help to address trial participants' concerns and misconceptions. Future research should evaluate the impact of educational materials in recruitment and retention of trial participants.
Cheleuitte-Nieves C, Heselpoth RD, Westblade LF, Lipman NS, Fischetti VA
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Searching for a Bacteriophage Lysin to Treat Corynebacterium bovis in Immunocompromised Mice

COMPARATIVE MEDICINE 2020 AUG; 70(4):328-335
Corynebacterium bovis is the causative agent of Corynebacterium-associated hyperkeratosis in immunocompromised mice. The resulting skin pathology can be profound and can be associated with severe wasting, making the animals unsuitable for research. Although the administration of antibiotics is effective in resolving clinical symptoms, antibiotics do not eradicate the offending bacterium. Furthermore, antibiotic use may be contraindicated as it can affect tumor growth and is associated with Clostridioides difficile enterotoxemia in highly immunocompromised murine strains. Lysins, which are lytic enzymes obtained from bacteriophages, are novel antimicrobial agents for treating bacterial diseases. The advantage of lysins are its target specificity, with minimal off-target complications that could affect the host or the biology of the engrafted tumor. The aim of this study was to identify lysins active against C. bovis. Chemical activation of latent prophages by using mitomycin C in 3 C. bovis isolates did not cause bacteriophage induction as determined through plaque assays and transmission electron microscopy. As an alternative approach, 8 lysins associated with other bacterial species, including those from the closely related species C. falsenii, were tested for their lytic action against C. bovis but were unsuccessful. These findings were congruent with the previously reported genomic analysis of 21 C. bovis isolates, which failed to reveal bacteriophage sequences by using the PHAST and PHASTER web server tools. From these results, we suggest C. bovis is among those rare bacterial species devoid of lysogenic bacteriophages, thus making the identification of C. bovis-specific lysins more challenging. However, C. bovis may be a useful model organism for studying the effects of antiphage systems.
Walker JM, Garcet S, Aleman JO, Mason CE, Danko D, Zuffa S, Swann JR, Krueger J, Breslow JL, Holt PR
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Obesity and ethnicity alter gene expression in skin

SCIENTIFIC REPORTS 2020 AUG 21; 10(1):? Article 14079
Obesity is accompanied by dysfunction of many organs, but effects on the skin have received little attention. We studied differences in epithelial thickness by histology and gene expression by Affymetrix gene arrays and PCR in the skin of 10 obese (BMI 35-50) and 10 normal weight (BMI 18.5-26.9) postmenopausal women paired by age and ethnicity. Epidermal thickness did not differ with obesity but the expression of genes encoding proteins associated with skin blood supply and wound healing were altered. In the obese, many gene expression pathways were broadly downregulated and subdermal fat showed pronounced inflammation. There were no changes in skin microbiota or metabolites. African American subjects differed from European Americans with a trend to increased epidermal thickening. In obese African Americans, compared to obese European Americans, we observed altered gene expression that may explain known differences in water content and stress response. African Americans showed markedly lower expression of the gene encoding the cystic fibrosis transmembrane regulator characteristic of the disease cystic fibrosis. The results from this preliminary study may explain the functional changes found in the skin of obese subjects and African Americans.
Patel ZS, Hoffman LK, Sutton L, Cohen SR, Lowes MA, Seng EK
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The patient experience of pain in hidradenitis suppurativa

BRITISH JOURNAL OF DERMATOLOGY 2020 AUG; 183(2):401-402
Dear Editor, Nielsen et al.1 recently highlighted the need for additional studies detailing pain in hidradenitis suppurativa (HS) before giving specific treatment recommendations. Few studies have evaluated HS‐specific pain using patients’ own words, and this study was designed to address this gap. A descriptive understanding of different elements of the pain experience will aid dermatologists, pain management specialists and health psychologists in the comprehensive, interdisciplinary assessment and treatment of HS.
Henriques F, Bedard AH, Guilherme A, Kelly M, Chi JY, Zhang P, Lifshitz LM, Bellve K, Rowland LA, Yenilmez B, Kumar S, Wang YT, Luban J, Weinstein LS, Lin JD, Cohen P, Czech MP
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Single-Cell RNA Profiling Reveals Adipocyte to Macrophage Signaling Sufficient to Enhance Thermogenesis

CELL REPORTS 2020 AUG 4; 32(5):? Article 107998
Adipocytes deficient in fatty acid synthase (iAdFASNKO) emit signals that mimic cold exposure to enhance the appearance of thermogenic beige adipocytes in mouse inguinal white adipose tissues (iWATs). Both cold exposure and iAdFASNKO upregulate the sympathetic nerve fiber (SNF) modulator Neuregulin 4 (Nrg4), activate SNFs, and require adipocyte cyclic AMP/protein kinase A (cAMP/PKA) signaling for beige adipocyte appearance, as it is blocked by adipocyte Gs alpha deficiency. Surprisingly, however, in contrast to cold-exposed mice, neither iWAT denervation nor Nrg4 loss attenuated adipocyte browning in iAdFASNKO mice. Single-cell transcriptomic analysis of iWAT stromal cells revealed increased macrophages displaying gene expression signatures of the alternately activated type in iAdFASNKO mice, and their depletion abrogated iWAT beiging. Altogether, these findings reveal that divergent cellular pathways are sufficient to cause adipocyte browning. Importantly, adipocyte signaling to enhance alternatively activated macrophages in iAdFASNKO mice is associated with enhanced adipose thermogenesis independent of the sympathetic neuron involvement this process requires in the cold.
Noureddin M, Chan JL, Barradas K, Dimick-Santos L, Schabel E, Omokaro SO, Anania FA, Myers RP, Miller V, Sanyal AJ, Chalasani N, Anania FA, Bajaj J, Barradas K, Berzigotti A, Birman P, Bosch J, Brower A, Calboli D, Chalasani N, Chan JL, Charlton W, Dickinson K, Dimick-Santos L, Filozof C, Forsgren MF, Fuchs M, Garcia-Tsao G, Gonzalez-Abraldes J, Gruss HJ, Hansen M, Hosman S, Imperial J, Jones D, Lalazar G, Leinhard OD, Lyons E, McColgan B, Mehta R, Mesenbrink P, Miller V, Myers R, Noureddin M, Omokaro SO, Pei V, Ratziu V, Regev A, Riccio R, Sanyal A, Schabel E, Seo S, Smith A, Szitanyi P, Traber P
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Attribution of Nonalcoholic Steatohepatitis as an Etiology of Cirrhosis for Clinical Trials Eligibility: Recommendations From the Multi-stakeholder Liver Forum

GASTROENTEROLOGY 2020 AUG; 159(2):422-427.e1
Sun SX, White RR, Fischer KE, Zhang ZD, Austad SN, Vijg J
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Inducible aging inHydra oligactisimplicates sexual reproduction, loss of stem cells, and genome maintenance as major pathways

GEROSCIENCE 2020 AUG; 42(4):1119-1132
Freshwater polyps of the genusHydrado not age. However, temperature stress induces aging and a shift from reproduction by asexual budding to sexual gamete production in a cold-sensitive (CS) strain ofH. oligactis.We sequenced the transcriptome of a male CS strain before and after this life history shift and compared changes in gene expression relative to those seen in a cold-resistant (CR) strain that does not undergo a life history shift in response to altered temperature. We found that the switch from non-aging asexual reproduction to aging and sexual reproduction involves upregulation of genes not only involved in gametogenesis but also genes involved in cellular senescence, apoptosis, and DNA repair accompanied by a downregulation of genes involved in stem cell maintenance. These results suggest that aging is a byproduct of sexual reproduction-associated cellular reprogramming and underscore the power of theseH. oligactisstrains to identify intrinsic mechanisms of aging.
Kong XF, Worley L, Rinchai D, Bondet V, Jithesh PV, Goulet M, Nonnotte E, Rebillat AS, Conte M, Mircher C, Gurtler N, Liu LY, Migaud M, Elanbari M, Habib T, Ma CS, Bustamante J, Abel L, Ravel A, Lyonnet S, Munnich A, Duffy D, Chaussabel D, Casanova JL, Tangye SG, Boisson-Dupuis S, Puel A
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Three Copies of Four Interferon Receptor Genes Underlie a Mild Type I Interferonopathy in Down Syndrome

JOURNAL OF CLINICAL IMMUNOLOGY 2020 AUG; 40(6):807-819
Down syndrome (DS) is characterized by the occurrence of three copies of human chromosome 21 (HSA21). HSA21 contains a cluster of four interferon receptor (IFN-R) genes:IFNAR1,IFNAR2,IFNGR2, andIL10RB. DS patients often develop mucocutaneous infections and autoimmune diseases, mimicking patients with heterozygous gain-of-function (GOF)STAT1mutations, which enhance cellular responses to three types of interferon (IFN). A gene dosage effect at these four loci may contribute to the infectious and autoimmune manifestations observed in individuals with DS. We report high levels of IFN-alpha R1, IFN-alpha R2, and IFN-gamma R2 expression on the surface of monocytes and EBV-transformed-B (EBV-B) cells from studying 45 DS patients. Total and phosphorylated STAT1 (STAT1 and pSTAT1) levels were constitutively high in unstimulated and IFN-alpha- and IFN-gamma-stimulated monocytes from DS patients but lower than those in patients with GOFSTAT1mutations. Following stimulation with IFN-alpha or -gamma, but not with IL-6 or IL-21, pSTAT1 and IFN-gamma activation factor (GAF) DNA-binding activities were significantly higher in the EBV-B cells of DS patients than in controls. These responses resemble the dysregulated responses observed in patients withSTAT1GOF mutations. Concentrations of plasma type I IFNs were high in 12% of the DS patients tested (1.8% in the healthy controls). Levels of type I IFNs, IFN-Rs, and STAT1 were similar in DS patients with and without recurrent skin infections. We performed a genome-wide transcriptomic analysis based on principal component analysis and interferon modules on circulating monocytes. We found that DS monocytes had levels of both IFN-alpha- and IFN-gamma-inducible ISGs intermediate to those of monocytes from healthy controls and from patients with GOFSTAT1mutations. Unlike patients with GOFSTAT1mutations, patients with DS had normal circulating Th17 counts and a high proportion of terminally differentiated CD8(+)T cells with low levels of STAT1 expression. We conclude a mild interferonopathy in Down syndrome leads to an incomplete penetrance at both cellular and clinical level, which is not correlate with recurrent skin bacterial or fungal infections. The constitutive upregulation of type I and type II IFN-R, at least in monocytes of DS patients, may contribute to the autoimmune diseases observed in these individuals.