The Bright Side of Hematopoiesis: Regulatory Roles of ARID3a/Bright in Human and Mouse Hematopoiesis

ARID3a/Bright is a DNA-binding protein that was originally discovered for its ability to increase immunoglobulin transcription in antigen-activated B cells. It interacts with DNA as a dimer through its ARID, or A/T-rich interacting domain. In association with other proteins, ARID3a increased transcription of the immunoglobulin heavy chain and led to improved chromatin accessibility of the heavy chain enhancer. Constitutive expression of ARID3a in B lineage cells resulted in autoantibody production, suggesting its regulation is important. Abnormal ARID3a expression has also been associated with increased proliferative capacity and malignancy. Roles for ARID3a in addition to interactions with the immunoglobulin locus were suggested by transgenic and knockout mouse models. Over-expression of ARID3a resulted in skewing of mature B cell subsets and altered gene expression patterns of follicular B cells, whereas loss of function resulted in loss of B1 lineage B cells and defects in hematopoiesis. More recent studies showed that loss of ARID3a in adult somatic cells promoted developmental plasticity, alterations in gene expression patterns, and lineage fate decisions. Together, these data suggest new regulatory roles for ARID3a. The genes influenced by ARID3a are likely to play pivotal roles in lineage decisions, highlighting the importance of this understudied transcription factor

CD4(+) T follicular helper and IgA(+) B cell numbers in gut biopsies from HIV-infected subjects on antiretroviral therapy are similar to HIV-uninfected individuals

BACKGROUND: Disruption of gastrointestinal tract epithelial and immune barriers contribute to microbial translocation, systemic inflammation, and progression of HIV-1 infection. Antiretroviral therapy (ART) may lead to reconstitution of CD4(+) T cells in gut-associated lymphoid tissue (GALT), but its impact on humoral immunity within GALT is unclear. Therefore, we studied CD4(+) subsets, including T follicular helper cells (Tfh), as well as resident B cells that have switched to IgA production, in gut biopsies, from HIV(+) subjects on suppressive ART compared to HIV-negative controls (HNC). METHODS: Twenty-three HIV(+) subjects on ART and 22 HNC undergoing colonoscopy were recruited to the study. Single-cell suspensions were prepared from biopsies from left colon (LC), right colon (RC), and terminal ileum (TI). T and B lymphocyte subsets, as well as EpCAM(+) epithelial cells, were accurately enumerated by flow cytometry, using counting beads. RESULTS: No significant differences in the number of recovered epithelial cells were observed between the two subject groups. However, the median TI CD4(+) T cell count/10(6) epithelial cells was 2.4-fold lower in HIV(+) subjects versus HNC (19,679 versus 47,504 cells; p = 0.02). Similarly, median LC CD4(+) T cell counts were reduced in HIV(+) subjects (8,358 versus 18,577; p = 0.03) but were not reduced in RC. Importantly, we found no significant differences in Tfh or IgA(+) B cell counts at either site between HIV(+) subjects and HNC. Further analysis showed no difference in CD4(+), Tfh, or IgA(+) B cell counts between subjects who commenced ART in primary compared to chronic HIV-1 infection. Despite the decrease in total CD4 T cells, we could not identify a selective decrease of other key subsets of CD4(+) T cells, including CCR5(+) cells, CD127(+) long-term memory cells, CD103(+) tissue-resident cells, or CD161(+) cells (surrogate marker for Th17), but there was a slight increase in the proportion of T regulatory cells. CONCLUSION: While there were lower absolute CD4(+) counts in the TI and LC in HIV(+) subjects on ART, they were not associated with significantly reduced Tfh cell counts or IgA(+) B cells, suggesting that this important vanguard of adaptive immune defense against luminal microbial products is normalized following ART.John Zaunders, Mark Danta, Michelle Bailey, Gerald Mak, Katherine Marks, Nabila Seddiki, Yin Xu, David J. Templeton, David A. Cooper, Mark A. Boyd, Anthony D. Kelleher and Kersten K. Koelsc

National Institutes of Health Stroke Scale (NIHSS) scoring inconsistencies between neurologists and emergency room nurses

BACKGROUND: Little is known about the consistency of initial NIHSS scores between neurologists and RNs in clinical practice. METHODS: A cohort study of patients with a code stroke was conducted at an urban academic Primary Stroke Center in the Midwest between January 1, 2018, and December 31, 2019 to determine consistency in National Institutes of Health Stroke Scale Scores (NIHSS) between neurologists and registered nurses (RNs). RESULTS: Among the 438 patients included in this study 65.3% (n = 286) of neurologist-RN NIHSS scoring pairs had congruent scores. One-in-three, (34.7%, n = 152) of neurologist-RN NIHSS scoring pairs had a clinically meaningful scoring difference of two points or greater. Higher NIHSS (p ≤ 0.01) and aphasia (p ≤ 0.01) were each associated with incongruent scoring between neurologist and emergency room RN pairs. CONCLUSIONS: One-in-three initial NIHSS assessed by both a neurologist and RN had a clinically meaningful score difference between providers. More severe stroke, as indicated by a higher NIHSS was associated with scoring inconsistency between neurologist-RN pairs. Subjective scoring measures, especially those involving a patient having aphasia, was associated with greater score incongruency. Score differences may be attributed to differences in NIHSS training requirements between neurologists and RNs

Sustained transmission of high-level azithromycin-resistant Neisseria gonorrhoeae in England: an observational study.

BACKGROUND: Between Nov 3, 2014, and Feb 24, 2017, 70 cases of high-level azithromycin-resistant (HL-AziR; minimum inhibitory concentration [MIC] ≥256 mg/L) Neisseria gonorrhoeae were reported from across England. Whole-genome sequencing was done to investigate this outbreak to determine whether the ongoing outbreak represented clonal spread of an HL-AziR N gonorrhoeae strain identified in Leeds. We also wanted to elucidate the molecular mechanisms of azithromycin resistance in N gonorrhoeae in the UK. METHODS: In this observational study, whole-genome sequencing was done on the HL-AziR N gonorrhoeae isolates from England. As comparators, 110 isolates from the UK and Ireland with a range of azithromycin MICs were also sequenced, including eight isolates from Scotland with azithromycin MICs ranging from 0·12 mg/L to 1·00 mg/L that were N gonorrhoeae multi-antigen sequence type 9768 (ST9768), which was the sequence type initially responsible for the outbreak. The presence of mutations or genes associated with azithromycin resistance was also investigated. FINDINGS: 37 of the 60 HL-AziR isolates from England belonged to ST9768, and were genetically similar (mean 4·3 single-nucleotide polymorphisms). A 2059A→G mutation was detected in three or all four alleles of the 23S rRNA gene. Five susceptible ST9768 isolates had one mutated 23S rRNA allele and one low-level resistant ST9768 isolate had two mutated alleles. INTERPRETATION: Sustained transmission of a successful HL-AziR clone was seen across England. Mutation 2059A→G was found in isolates with lower azithromycin MICs. Azithromycin exposure might have provided the selection pressure for one or two mutated copies of the 23S rRNA gene to recombine with wild-type copies, leading to three or four mutated copies and the HL-AziR phenotype. HL-AziR could emerge in isolates with low azithromycin MICs and eliminate the effectiveness of azithromycin as part of dual therapy for the treatment of gonorrhoea. FUNDING: Public Health England

Investigating the decline in Lymphogranuloma venereum diagnoses in men who have sex with men in the United Kingdom since 2016: an analysis of surveillance data.

BACKGROUND: Following an upward trajectory in Lymphogranuloma venereum (LGV) diagnoses in the UK from 2004 to 2016, with annual diagnoses increasing from 28 to 904, diagnoses fell to 641 in 2017; this was inconsistent with the upward trend in other bacterial sexually transmissible infections (STIs) between 2016 and 2017. An analysis of surveillance data from multiple sources to investigate the possible factors contributing to this decline in LGV was performed. METHODS: LGV tests and diagnoses in the UK from 2004 to 2018 were captured through laboratory data from the LGV Reference Laboratories and laboratories conducting in-house LGV testing. These data and clinical diagnoses data from England were analysed alongside the national management guidelines issued over the course of the epidemic. RESULTS: LGV diagnoses increased between 2004 and 2015 and then decreased between 2016 and 2018. LGV testing increased from 2010 to 2018 (2690-10850). Test positivity halved between 2015 (14.8%, 929-6272) and 2018 (7.3%, 791-10850). Peaks in LGV testing and diagnoses appeared to coincide with the publication of national LGV management guidelines and changes to clinical practice. The proportion of LGV diagnoses among HIV-positive men who have sex with men (MSM) fell between 2013 and 2018 (74-48%). CONCLUSIONS: The fall in diagnoses and positivity were likely due to increasing earlier clinical diagnosis and treatment. Changes to the national management guidelines, the clinical policy and practice of some larger clinics and potentially changes to the guidelines for the treatment of chlamydia broadened the scope of testing and increased testing in asymptomatic patients which, in combination, likely had a positive effect on the control of LGV infection

Significant increase in azithromycin “resistance” and susceptibility to ceftriaxone and cefixime in Neisseria gonorrhoeae isolates in 26 European countries, 2019

Euro-GASP network: Claudia Eder, Sonja Pleininger, Steliana Huhlescu, Irith de Baetselier, Blaženka Hunjak, Tatjana Nemeth Blažić, Panagiota Maikanti-Charalampous, Despo Pieridou, Hana Zákoucká, Helena Žemličková, Steen Hoffmann, Susan Cowan, Rita Peetso, Jelena Viktorova, Ndeindo Ndeikoundam, Beatrice Bercot, Anu Patari Sampo, Vesa Kirjavainen, Susanne Buder, Klaus Jansen, Vivi Miriagou, Eszter Balla, Mária Dudás, Guðrún Sigmundsdóttir, Lena Ros Asmundsdottir, Sinead Saab, Brendan Crowley, Anna Carannante, Paola Stefanelli, Gatis Pakarna, Violeta Mavcutko, Robert Cassar, Christopher Barbara, Francesca Vella, Alje Van Dam, Ineke Linde, Dominique Caugant, Hilde Kløvstad, Beata Mlynarczyk-Bonikowska, Maria-José Borrego, Peter Pavlik, Irena Klavs, Tanja Kustec, Julio Vazquez, Asuncion Diaz, Raquel Abad Torreblanca, Inga Velicko, Magnus Unemo, Helen Fifer, Kate TempletonBackground: The European Gonococcal Antimicrobial Surveillance Programme (Euro-GASP) performs annual sentinel surveillance of Neisseria gonorrhoeae susceptibility to therapeutically relevant antimicrobials across the European Union/European Economic Area (EU/EEA). We present the Euro-GASP results from 2019 (26 countries), linked to patient epidemiological data, and compared with data from previous years. Methods: Agar dilution and minimum inhibitory concentration (MIC) gradient strip methodologies were used to determine the antimicrobial susceptibility (using EUCAST clinical breakpoints, where available) of 3239 N. gonorrhoeae isolates from 26 countries across the EU/EEA. Significance of differences compared with Euro-GASP results in previous years was analysed using Z-test and the Pearson's χ2 test was used to assess significance of odds ratios for associations between patient epidemiological data and antimicrobial resistance. Results: European N. gonorrhoeae isolates collected between 2016 and 2019 displayed shifting MIC distributions for; ceftriaxone, with highly susceptible isolates increasing over time and occasional resistant isolates each year; cefixime, with highly-susceptible isolates becoming increasingly common; azithromycin, with a shift away from lower MICs towards higher MICs above the EUCAST epidemiological cut-off (ECOFF); and ciprofloxacin which is displaying a similar shift in MICs as observed for azithromycin. In 2019, two isolates displayed ceftriaxone resistance, but both isolates had MICs below the azithromycin ECOFF. Cefixime resistance (0.8%) was associated with patient sex, with resistance higher in females compared with male heterosexuals and men-who-have-sex-with-men (MSM). The number of countries reporting isolates with azithromycin MICs above the ECOFF increased from 76.9% (20/26) in 2016 to 92.3% (24/26) in 2019. Isolates with azithromycin MICs above the ECOFF (9.0%) were associated with pharyngeal infection sites. Following multivariable analysis, ciprofloxacin resistance remained associated with isolates from MSM and heterosexual males compared with females, the absence of a concurrent chlamydial infection, pharyngeal infection sites and patients ≥ 25 years of age. Conclusions: Resistance to ceftriaxone and cefixime remained uncommon in EU/EEA countries in 2019 with a significant decrease in cefixime resistance observed between 2016 and 2019. The significant increase in azithromycin "resistance" (azithromycin MICs above the ECOFF) threatens the effectiveness of the dual therapy (ceftriaxone + azithromycin), i.e., for ceftriaxone-resistant cases, currently recommended in many countries internationally and requires close monitoring.The study was funded by the European Centre for Disease Prevention and Control (Framework Contract No. ECDC/2017/004).info:eu-repo/semantics/publishedVersio