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Transcriptional down-regulation of ccr5 in a subset of HIV+ controllers and their family members.
HIV +Elite and Viremic controllers (EC/VCs) are able to control virus infection, perhaps because of host genetic determinants. We identified 16% (21 of 131) EC/VCs with CD4 +T cells with resistance specific to R5-tropic HIV, reversed after introduction of ccr5. R5 resistance was not observed in macrophages and depended upon the method of T cell activation. CD4 +T cells of these EC/VCs had lower ccr2 and ccr5 RNA levels, reduced CCR2 and CCR5 cell-surface expression, and decreased levels of secreted chemokines. T cells had no changes in chemokine receptor mRNA half-life but instead had lower levels of active transcription of ccr2 and ccr5, despite having more accessible chromatin by ATAC-seq. Other nearby genes were also down-regulated, over a region of ~500 kb on chromosome 3p21. This same R5 resistance phenotype was observed in family members of an index VC, also associated with ccr2/ccr5 down-regulation, suggesting that the phenotype is heritable
Pattern of Disease after Murine Hepatitis Virus Strain 3 Infection Correlates with Macrophage Activation and Not Viral Replication
Murine hepatitis virus strain (MHV-3) produces a strain-dependent pattern of disease which has been used as a model for fulminant viral hepatitis. This study was undertaken to examine whether there was a correlation between macrophage activation and susceptibility or resistance to MHV-3 infection. Peritoneal macrophages were isolated from resistant A/J and susceptible BALB/cJ mice and, following stimulation with MHV-3 or lipopolysaccharide (LPS), analyzed for transcription of mRNA and production of interleukin-1 (IL-1), tumor necrosis factor alpha (TNF-alpha), transforming growth factor beta (TGF-beta), mouse fibrinogen-like protein (musfiblp), tissue factor (TF), leukotriene B4, and prostaglandin E2 (PGE2). Macrophages from BALB/cJ mice produced greater amounts of IL-1, TNF-alpha, TGF-beta, leukotriene B4, and musfiblp following MHV-3 infection than macrophages from resistant A/J mice, whereas in response to LPS, equivalent amounts of IL-1, TNF-alpha, TGF-beta, and TF were produced by macrophages from both strains of mice. Levels of mRNA of IL-1, TNF-alpha, and musfiblp were greater and more persistent in BALB/cJ than in A/J macrophages, whereas the levels and kinetics of IL-1, TNF-alpha, and TF mRNA following LPS stimulation were identical in macrophages from both strains of mice. Levels of production of PGE2 by MHV-3-stimulated macrophages from resistant and susceptible mice were equivalent; however, the time course for induction of PGE2, differed, but the total quantity of PGE2 produced was insufficient to inhibit induction of musfiblp, a procoagulant known to correlate with development of fulminant hepatic necrosis in susceptible mice. These results demonstrate marked differences in production of inflammatory mediators to MHV-3 infection in macrophages from resistant A/J and susceptible BALB/cJ mice, which may explain the marked hepatic necrosis and fibrin deposition and account for the lethality of MHV-3 in susceptible mice
Molecular Mimicry between Fc Receptor and S Peplomer Protein of Mouse Hepatitis Virus, Bovine Corona Virus, and Transmissible Gastroenteritis Virus [Abstract]
The Ups and Downs in Women's Employment: Shifting Composition or Behavior from 1970 to 2010?
This paper tracks factors contributing to the ups and downs in women’s employment from 1970 to 2010 using regression decompositions focusing on whether changes are due to shifts in the means (composition of women) or due to shifts in coefficients (inclinations of women to work for pay). Compositional shifts in education exerted a positive effect on women’s employment across all decades, while shifts in the composition of other family income, particularly at the highest deciles, depressed married women’s employment over the 1990s contributing to the slowdown in this decade. A positive coefficient effect of education was found in all decades, except the 1990s, when the effect was negative, depressing women’s employment. Further, positive coefficient results for other family income at the highest deciles bolstered married women’s employment over the 1990s. Models are run separately for married and single women demonstrating the varying results of other family income by marital status. This research was supported in part by an Upjohn Institute Early Career Research Award
Para-infectious brain injury in COVID-19 persists at follow-up despite attenuated cytokine and autoantibody responses
To understand neurological complications of COVID-19 better both acutely and for recovery, we measured markers of brain injury, inflammatory mediators, and autoantibodies in 203 hospitalised participants; 111 with acute sera (1–11 days post-admission) and 92 convalescent sera (56 with COVID-19-associated neurological diagnoses). Here we show that compared to 60 uninfected controls, tTau, GFAP, NfL, and UCH-L1 are increased with COVID-19 infection at acute timepoints and NfL and GFAP are significantly higher in participants with neurological complications. Inflammatory mediators (IL-6, IL-12p40, HGF, M-CSF, CCL2, and IL-1RA) are associated with both altered consciousness and markers of brain injury. Autoantibodies are more common in COVID-19 than controls and some (including against MYL7, UCH-L1, and GRIN3B) are more frequent with altered consciousness. Additionally, convalescent participants with neurological complications show elevated GFAP and NfL, unrelated to attenuated systemic inflammatory mediators and to autoantibody responses. Overall, neurological complications of COVID-19 are associated with evidence of neuroglial injury in both acute and late disease and these correlate with dysregulated innate and adaptive immune responses acutely
Binding of Alz 50 depends on Phe\u3csup\u3e8\u3c/sup\u3e in tau synthetic peptides and varies between native and denatured tau proteins
Alz 50 is a monoclonal antibody that in Western blotting analysis recognizes both normal tau as well as hyperphosphorylated tau proteins associated with paired helical filaments (PHF-tau) in Alzheimer disease (AD). Within tissue sections of AD brain, however, Alz 50 immunolabels only PHF, which suggests that the antibody recognizes a conformational epitope. Using competitive enzyme-linked immunosorbent assay, we demonstrate that Alz 50 binds to tau synthetic peptides with low affinity (KD between 0.27 to 2.7 × 10-5 M) and that the binding is specific for the RQEF sequence corresponding to N-terminal residues 5-8 of tau. The Alz 50 epitope appears to be largely dependent on Phe8, a strongly hydrophobic amino acid residue, since the substitution of Phe8 with Ala8 in the synthetic peptide abolishes Alz 50 binding. The effects of tau conformation on Alz 50 binding were studied with various normal tau proteins with either low or high phosphate content (adult vs. fetal) and PHF-tau proteins. The normal tau fractions were isolated from both adult and fetal human brains using affinity chromatography (native form) and heat/perchloric acid treatments (denatured form). PHF-tau was isolated as Sarcosyl-insoluble fraction. With competitive ELISA, the denatured form of normal tau (fetal and adult) bound Alz 50 with the same high affinity as did PHF-tau (KD between 1.3 to 1.8 × 10-7 M). In contrast, the native form of tau from either brain was unable to fully compete for Alz 50 and at most only 50% of the Alz 50 binding sites in native tau were occupied. These results suggest that native tau may exist either in complexes with other proteins or in a form of dimers/oligomers, in which only some N-termini are available for binding (e.g. head-to-tail assembly). The results also suggest that denaturation rather than phosphorylation of tau has more significant effect on interactions of tau with Alz 50. © 1995 Elsevier Science B.V. All rights reserved
Effects of Methionine Gamma Lyase-Deaminase on Human Colorectal Carcinoma Cells
Objective. The objective of this study is to demonstrate the effects of methionine gamma lyase-deaminase (Mgld) on colorectal carcinoma cell survival using MTT assay. Background. Mgld is in enzyme found in bacteria and protozoa including, Porphyromonas gingivalis. Mgld has the ability to catabolize methionine, an enzyme function that is absent in mammals. This enzyme function is of interest in methionine/S-adenosyl methionine (SAM) dependent cancer cells given the dysregulation of DNA methylation patterns that occur compared to normal mammalian cells. Methods. In this study, Porphyromonas gingivalis Mgld cloned into a cytoplasmic and nuclear plasmid vector was transfected into the human colorectal carcinoma T84 cell line using Lipofectamine 3000. The effects of cytoplasmic Mgld and nuclear Mgld were assessed in comparison to control non-transfected cells. Cell survival was assessed with an MTT assay at 570 nm as an indicator of metabolic functions of the live cells/mitochondria. Results. Results indicate that nuclear Mgld transfection causes most significant inhibition of metabolic activity in T84 colorectal carcinoma cells with a 19% decrease in absorbance compared to the control. Conclusion. Due to its effects on cellular survival, further studies should be conducted to evaluate and investigate the metabolic implications of nuclear Mgld on T84 colorectal carcinoma cells