50 research outputs found
Omega-3 Fatty Acid and Iron Supplementation Alone, but Not in Combination, Lower Inflammation and Anemia of Infection in Mycobacterium tuberculosis-Infected Mice
Progressive inflammation and anemia are common in tuberculosis (TB) and linked to poor clinical outcomes. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have inflammation-resolving properties, whereas iron supplementation in TB may have limited efficacy and enhance bacterial growth. We investigated effects of iron and EPA/DHA supplementation, alone and in combination, on inflammation, anemia, iron status markers and clinical outcomes in Mycobacterium tuberculosis-infected C3HeB/FeJ mice. One week post-infection, mice received the AIN-93 diet without (control) or with supplemental iron (Fe), EPA/DHA, or Fe+EPA/DHA for 3 weeks. Mice supplemented with Fe or EPA/DHA had lower soluble transferrin receptor, ferritin and hepcidin than controls, but these effects were attenuated in Fe+EPA/DHA mice. EPA/DHA increased inflammation-resolving lipid mediators and lowered lung IL-1α, IFN-γ, plasma IL-1β, and TNF-α. Fe lowered lung IL-1α, IL-1β, plasma IL-1β, TNF-α, and IL-6. However, the cytokine-lowering effects in the lungs were attenuated with Fe+EPA/DHA. Mice supplemented with EPA/DHA had lower lung bacterial loads than controls, but this effect was attenuated in Fe+EPA/DHA mice. Thus, individually, post-infection EPA/DHA and iron supplementation lowered systemic and lung inflammation and mitigated anemia of infection in TB, but not when combined. EPA/DHA also enhanced bactericidal effects and could support inflammation resolution and management of anemia
Adjunct n-3 Long-Chain Polyunsaturated Fatty Acid Treatment in Tuberculosis Reduces Inflammation and Improves Anemia of Infection More in C3HeB/FeJ Mice With Low n-3 Fatty Acid Status Than Sufficient n-3 Fatty Acid Status
Populations at risk for tuberculosis (TB) may have a low n-3 polyunsaturated fatty acid
(PUFA) status. Our research previously showed that post-infection supplementation of
n-3 long-chain PUFA (LCPUFA) in TB without TB medication was beneficial in n-3
PUFA sufficient but not in low-status C3HeB/FeJ mice. In this study, we investigated
the effect of n-3 LCPUFA adjunct to TB medication in TB mice with a low compared
to a sufficient n-3 PUFA status. Mice were conditioned on an n-3 PUFA-deficient (n-
3FAD) or n-3 PUFA-sufficient (n-3FAS) diet for 6 weeks before TB infection. Postinfection
at 2 weeks, both groups were switched to an n-3 LCPUFA [eicosapentaenoic
acid (EPA)/docosahexaenoic acid (DHA)] supplemented diet and euthanized at 4- and
14- days post-treatment. Iron and anemia status, bacterial loads, lung pathology, lung
cytokines/chemokines, and lung lipid mediators were measured. Following 14 days of
treatment, hemoglobin (Hb) was higher in the n-3FAD than the untreated n-3FAS group
(p = 0.022), whereas the n-3FAS (drug) treated control and n-3FAS groups were not. Proinflammatory
lung cytokines; interleukin-6 (IL-6) (p = 0.011), IL-1a (p = 0.039), MCP1
(p = 0.003), MIP1- a (p = 0.043), and RANTES (p = 0.034); were lower, and the antiinflammatory
cytokine IL-4 (p=0.002) and growth factor GMCSF (p=0.007) were higher
in the n-3FAD compared with the n-3FAS mice after 14 days. These results suggest that
n-3 LCPUFA therapy in TB-infected mice, in combination with TB medication, may
improve anemia of infection more in low n-3 fatty acid status than sufficient status mice.
Furthermore, the low n-3 fatty acid status TB mice supplemented with n-3 LCPUFA
showed comparatively lower cytokine-mediated inflammation despite presenting with
lower pro-resolving lipid mediators
Omega-3 long-chain polyunsaturated fatty acids promote antibacterial and inflammation-resolving effects in Mycobacterium tuberculosis-infected C3HeB/FeJ mice, dependent on fatty acid status
AbstractNon-resolving inflammation is characteristic of tuberculosis (TB). Given their inflammation-resolving properties,n-3 long-chain PUFA (n-3 LCPUFA) may support TB treatment. This research aimed to investigate the effects ofn-3 LCPUFA on clinical and inflammatory outcomes ofMycobacterium tuberculosis-infected C3HeB/FeJ mice with either normal or lown-3 PUFA status before infection. Using a two-by-two design, uninfected mice were conditioned on either ann-3 PUFA-sufficient (n-3FAS) or -deficient (n-3FAD) diet for 6 weeks. One week post-infection, mice were randomised to eithern-3 LCPUFA supplemented (n-3FAS/n-3+ andn-3FAD/n-3+) or continued onn-3FAS orn-3FAD diets for 3 weeks. Mice were euthanised and fatty acid status, lung bacterial load and pathology, cytokine, lipid mediator and immune cell phenotype analysed.n-3 LCPUFA supplementation inn-3FAS mice lowered lung bacterial loads (P= 0·003), T cells (P= 0·019), CD4+T cells (P= 0·014) and interferon (IFN)-γ(P< 0·001) and promoted a pro-resolving lung lipid mediator profile. Compared withn-3FAS mice, then-3FAD group had lower bacterial loads (P= 0·037), significantly higher immune cell recruitment and a more pro-inflammatory lipid mediator profile, however, significantly lower lung IFN-γ, IL-1α, IL-1βand IL-17, and supplementation in then-3FAD group provided no beneficial effect on lung bacterial load or inflammation. Our study provides the first evidence thatn-3 LCPUFA supplementation has antibacterial and inflammation-resolving benefits in TB when provided 1 week after infection in the context of a sufficientn-3 PUFA status, whilst a lown-3 PUFA status may promote better bacterial control and lower lung inflammation not benefiting fromn-3 LCPUFA supplementation
Chimeric Antigen Receptor Signaling Domains Differentially Regulate Proliferation and Native T Cell Receptor Function in Virus-Specific T Cells
The efficacy of T cells expressing chimeric antigen receptors (CARs) for solid tumors has been limited by insufficient CAR T cell expansion and persistence. The use of virus-specific T cells (VSTs) as carriers for CARs may overcome this limitation since CAR-VSTs can be boosted by viral vaccines or oncolytic viruses. However, there is limited understanding of the optimal combination of endodomains and their influence on the native T cell receptor (TCR) in VSTs. We therefore compared the function of GD2.CARs expressing the TCR zeta chain (ζ) alone or combined with endodomains from CD28 and 4-1BB in varicella zoster virus-specific (VZV) T cells. VZVSTs expressing GD2-CARs recognized VZV-derived peptides and killed GD2-expressing tumor cells. However, after repeated stimulation through their native TCR, the expansion of GD2-CAR.CD28ζ-VZVSTs was 3.3-fold greater (p < 0.001) than non-transduced VZVSTs, whereas GD2-CARζ- and GD2-CAR.41BBζ inhibited VZVST expansion (p < 0.01). Compared to control VZVSTs, GD2-CAR.ζ VZVSTs showed a greater frequency of apoptotic (p < 0.01) T cells, whereas prolonged downregulation of the native αβ TCR was observed in GD2-CAR.41BBζ VZVSTs (p < 0.001). We confirmed that CD28ζ can best maintain TCR function by expressing GD2.CARs in Epstein-Barr virus-specific T cells and CD19-CARs in VZVSTs. In response to CAR stimulation VSTs with CD28ζ endodomains also showed the greatest expansion (6 fold > GD2-CAR.41BBζ VZVSTs (p < 0.001), however anti-tumor efficacy was superior in GD2-CAR.41BBζ-VZVSTs. These findings demonstrate that CAR signaling domains can enhance or diminish the function of the native TCR and indicate that only CD28ζ may preserve the function of the native TCR in tonically signaling CAR-VSTs
The Ninth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Baryon Oscillation Spectroscopic Survey
The Sloan Digital Sky Survey III (SDSS-III) presents the first spectroscopic
data from the Baryon Oscillation Spectroscopic Survey (BOSS). This ninth data
release (DR9) of the SDSS project includes 535,995 new galaxy spectra (median
z=0.52), 102,100 new quasar spectra (median z=2.32), and 90,897 new stellar
spectra, along with the data presented in previous data releases. These spectra
were obtained with the new BOSS spectrograph and were taken between 2009
December and 2011 July. In addition, the stellar parameters pipeline, which
determines radial velocities, surface temperatures, surface gravities, and
metallicities of stars, has been updated and refined with improvements in
temperature estimates for stars with T_eff<5000 K and in metallicity estimates
for stars with [Fe/H]>-0.5. DR9 includes new stellar parameters for all stars
presented in DR8, including stars from SDSS-I and II, as well as those observed
as part of the SDSS-III Sloan Extension for Galactic Understanding and
Exploration-2 (SEGUE-2).
The astrometry error introduced in the DR8 imaging catalogs has been
corrected in the DR9 data products. The next data release for SDSS-III will be
in Summer 2013, which will present the first data from the Apache Point
Observatory Galactic Evolution Experiment (APOGEE) along with another year of
data from BOSS, followed by the final SDSS-III data release in December 2014.Comment: 9 figures; 2 tables. Submitted to ApJS. DR9 is available at
http://www.sdss3.org/dr
Discovery of widespread transcription initiation at microsatellites predictable by sequence-based deep neural network
Using the Cap Analysis of Gene Expression (CAGE) technology, the FANTOM5 consortium provided one of the most comprehensive maps of transcription start sites (TSSs) in several species. Strikingly, ~72% of them could not be assigned to a specific gene and initiate at unconventional regions, outside promoters or enhancers. Here, we probe these unassigned TSSs and show that, in all species studied, a significant fraction of CAGE peaks initiate at microsatellites, also called short tandem repeats (STRs). To confirm this transcription, we develop Cap Trap RNA-seq, a technology which combines cap trapping and long read MinION sequencing. We train sequence-based deep learning models able to predict CAGE signal at STRs with high accuracy. These models unveil the importance of STR surrounding sequences not only to distinguish STR classes, but also to predict the level of transcription initiation. Importantly, genetic variants linked to human diseases are preferentially found at STRs with high transcription initiation level, supporting the biological and clinical relevance of transcription initiation at STRs. Together, our results extend the repertoire of non-coding transcription associated with DNA tandem repeats and complexify STR polymorphism
IL-12 enhances the natural killer cell cytokine response to Ab-coated tumor cells
The anti-tumor activity of recombinant mAb’s directed against tumor cell growth receptors has generally been considered to result from direct antiproliferative effects, the induction of apoptosis, or possibly Ab-dependent cellular cytotoxicity mediated against tumor targets. However, it remains unclear to what degree these mechanisms actually aid in the clearance of Ab-coated tumor cells in vivo. We show here that NK cells secrete a distinct profile of potent immunostimulatory cytokines in response to dual stimulation with Ab-coated tumor cells and IL-12. This response could not be duplicated by costimulation with other ILs and was significantly enhanced in the presence of monocytes. Cytokine production was dependent upon synergistic signals mediated by the activating receptor for the Fc portion of IgG (FcγRIII) and the IL-12 receptor expressed on NK cells. Coadministration of Ab-coated tumor cells and IL-12 to BALB/c mice resulted in enhanced circulating levels of NK cell–derived cytokines with the capacity to augment anti-tumor immunity. These findings suggest that, in addition to mediating cellular cytotoxicity and apoptosis, the anti-tumor activity of mAb’s might also result from activation of a potent cytokine secretion program within immune effectors capable of recognizing mAb-coated targets
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Interleukin-21 enhances NK cell activation in response to antibody-coated targets
NK cells express an activating FcR (FcgammaRIIIa) that mediates Ab-dependent cellular cytotoxicity and the production of immune modulatory cytokines in response to Ab-coated targets. IL-21 has antitumor activity in murine models that depends in part on its ability to promote NK cell cytotoxicity and IFN-gamma secretion. We hypothesized that the NK cell response to FcR stimulation would be enhanced by the administration of IL-21. Human NK cells cultured with IL-21 and immobilized IgG or human breast cancer cells coated with a therapeutic mAb (trastuzumab) secreted large amounts of IFN-gamma. Increased secretion of TNF-alpha and the chemokines IL-8, MIP-1alpha, and RANTES was also observed under these conditions. NK cell IFN-gamma production was dependent on distinct signals mediated by the IL-21R and the FcR and was abrogated in STAT1-deficient NK cells. Supernatants derived from NK cells that had been stimulated with IL-21 and mAb-coated breast cancer cells were able to drive the migration of naive and activated T cells in an in vitro chemotaxis assay. IL-21 also enhanced NK cell lytic activity against Ab-coated tumor cells. Coadministration of IL-21 and Ab-coated tumor cells to immunocompetent mice led to synergistic production of IFN-gamma by NK cells. Furthermore, the administration of IL-21 augmented the effects of an anti-HER2/neu mAb in a murine tumor model, an effect that required IFN-gamma. These findings demonstrate that IL-21 significantly enhances the NK cell response to Ab-coated targets and suggest that IL-21 would be an effective adjuvant to administer in combination with therapeutic mAbs