Survival of tissue-resident memory T cells requires exogenous lipid uptake and metabolism

Pan, Youdong,Tian, Tian,Park, Chang Ook,Lofftus, Serena Y.,Mei, Shenglin,Liu, Xing,Luo, Chi,O’Malley, John T.,Gehad, Ahmed,Teague, Jessica E.,Divito, Sherrie J.,Fuhlbrigge, Robert,Puigserver, Pere,Kru Macmillan Publishers Limited, part of Springer Nat 2017 Nature Vol.543 No.7644

Tissue-resident memory T (T<SUB>RM</SUB>) cells persist indefinitely in epithelial barrier tissues and protect the host against pathogens. However, the biological pathways that enable the long-term survival of T<SUB>RM</SUB> cells are obscure. Here we show that mouse CD8<SUP>+</SUP> T<SUB>RM</SUB> cells generated by viral infection of the skin differentially express high levels of several molecules that mediate lipid uptake and intracellular transport, including fatty-acid-binding proteins 4 and 5 (FABP4 and FABP5). We further show that T-cell-specific deficiency of Fabp4 and Fabp5 (Fabp4/Fabp5) impairs exogenous free fatty acid (FFA) uptake by CD8<SUP>+</SUP> T<SUB>RM</SUB> cells and greatly reduces their long-term survival in vivo, while having no effect on the survival of central memory T (T<SUB>CM</SUB>) cells in lymph nodes. In vitro, CD8<SUP>+</SUP> T<SUB>RM</SUB> cells, but not CD8<SUP>+</SUP> T<SUB>CM</SUB> cells, demonstrated increased mitochondrial oxidative metabolism in the presence of exogenous FFAs; this increase was not seen in Fabp4/Fabp5 double-knockout CD8<SUP>+</SUP> T<SUB>RM</SUB> cells. The persistence of CD8<SUP>+</SUP> T<SUB>RM</SUB> cells in the skin was strongly diminished by inhibition of mitochondrial FFA β-oxidation in vivo. Moreover, skin CD8<SUP>+</SUP> T<SUB>RM</SUB> cells that lacked Fabp4/Fabp5 were less effective at protecting mice from cutaneous viral infection, and lung Fabp4/Fabp5 double-knockout CD8<SUP>+</SUP> T<SUB>RM</SUB> cells generated by skin vaccinia virus (VACV) infection were less effective at protecting mice from a lethal pulmonary challenge with VACV. Consistent with the mouse data, increased FABP4 and FABP5 expression and enhanced extracellular FFA uptake were also demonstrated in human CD8<SUP>+</SUP> T<SUB>RM</SUB> cells in normal and psoriatic skin. These results suggest that FABP4 and FABP5 have a critical role in the maintenance, longevity and function of CD8<SUP>+</SUP> T<SUB>RM</SUB> cells, and suggest that CD8<SUP>+</SUP> T<SUB>RM</SUB> cells use exogenous FFAs and their oxidative metabolism to persist in tissue and to mediate protective immunity.

The enhanced phosphorescence from Alq₃ fluorescent materials by phosphor sensitization

Tsuboi, T.,Kwon, J.H.,Liu, X.,Huang, W. Elsevier Sequoia 2014 Journal of photochemistry and photobiology Chemist Vol.291 No.-

The green emission accompanied with intense red phosphorescence is observed from the tris(8-hydroxyquinoline) aluminum (Alq<SUB>3</SUB>) in the heavily doped tris(2-phenylpyridine) iridium [Ir(ppy)<SUB>3</SUB>] films. This photoluminescence (PL) emission mechanism is studied by the PL excitation (PLE) spectra for the red and green emissions. From the PLE spectrum for the red emission, the energy transfer from Ir(ppy)<SUB>3</SUB> to Alq<SUB>3</SUB> is confirmed. The increase of the green emission with increasing temperature from 12K is explained by the endothermic back Forster energy transfer from the triplet T<SUB>1</SUB> state of Ir(ppy)<SUB>3</SUB> to the singlet S<SUB>1</SUB> state of Alq<SUB>3</SUB>. It is suggested that this back transfer is partially responsible for the decrease of the red emission intensity corresponding to the increase of the green emission. Unlike the Forster energy transfer, the Dexter energy transfer from the T<SUB>1</SUB> state of Ir(ppy)<SUB>3</SUB> to the T<SUB>1</SUB> state of Alq<SUB>3</SUB> is highly efficient. The explanation for this process is presented here. The green emission is not attributed to Ir(ppy)<SUB>3</SUB> but to Alq<SUB>3</SUB>, because not only the green emission profile but also the red emission profile is quite similar to the δ-phase polycrystalline Alq<SUB>3</SUB>. From these results, it is concluded that the Alq<SUB>3</SUB> forms a δ-phase polycrystalline state to accept the phosphor sensitization. The unusual enhancement of the red phosphorescence from the Alq<SUB>3</SUB> is explained by the mixing of the T<SUB>1</SUB> state of Ir(ppy)<SUB>3</SUB> with the T<SUB>1</SUB> state of Alq<SUB>3</SUB> under the Dexter energy transfer of short range process, by taking into account that the T<SUB>1</SUB> state of Ir(ppy)<SUB>3</SUB> contains the singlet state by the strong spin-orbit coupling.

The Probiotic and Adherence Properties of Lactobacillus reuteri Pg4 Expressing the Rumen Microbial β-Glucanase

Yu, B.,Liu, J.R.,Hsiao, F.S.,Lee, T.T.,Chiou, P.W.S. Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.9

This study was conducted to evaluate the potential of the transformed Lactobacillus reuteri Pg4 (T-Pg4) harboring the ${\beta}$-glucanase gene as a poultry probiotic. The probiotic properties of the T-Pg4 strain were evaluated in vitro by their adherence capability and acid and bile salt tolerance, and were evaluated in vivo by their survival and adhesion in the gastrointestinal tract (GIT) of specific-pathogen-free (SPF) chickens. The results showed that the T-Pg4 strain exhibited resistance to acidic conditions and contact with bile salt, and adhered efficiently to the crop and intestinal epithelial cells of chickens in vitro. The T-Pg4 strain also could survive and colonize the gastrointestinal epithelium of the experimental SPF chickens in vivo. In addition, radial enzyme diffusion was used to demonstrate that the Lactobacillus spp. randomly isolated from the GIT of the SPF chickens fed T-Pg4 possessed ${\beta}$-glucanase secretion capability. These findings have demonstrated that the transformed L. reuteri Pg4 survives transit through the stomach and intestine, and may secrete ${\beta}$-glucanase in the chicken GIT. Therefore, it is suggested that this organism could be used as a multifunctional poultry probiotic.

Influence of aromatic heterocycle of conjugated side chains on photovoltaic performance of benzodithiophene-based wide-bandgap polymers

Xue, X.,Fan, B.,Liu, T.,Sun, X.,Huo, L.,Ha, S.,Choi, H.,Kim, T.,Kim, J.,Wei, D. Royal Society of Chemistry 2016 Polymer chemistry Vol.7 No.24

<P>Extensive efforts have been focused on the study of wide-band gap (WBG) polymers due to their important applications in multiple junction and ternary blend organic solar cells. Herein, three WBG copolymers named PBDT(X)-T1 (X = O, S, Se) were synthesized based on the benzodithiophene (BDT) donor unit and 1,3-bis(5-bromothiophen-2-yl)-5,7-bis(2-ethylhexyl)-4H, 8H-benzo[1,2-c: 4,5-c']dithiophene-4,8-dione (T1) acceptor unit. Different aromatic heterocycle groups (furan, thiophene and selenophene) were introduced to modify the BDT unit to investigate the influence of conjugated side chains on the photovoltaic properties of conjugated polymers. Photophysical properties, electrochemistry, charge transport and crystalline properties of the polymers were studied to discuss the role of chalcogen atoms on the performance of conjugated polymers. Solar cells based on these three WBG copolymers were fabricated. Among them, the PBDT(Se)-T1-based solar cell shows the best photovoltaic performance with the highest power conversion efficiency (PCE) of 8.52%, an open-circuit voltage (V-oc) of 0.91 V, and a high fill factor (FF) of 72%. The high crystallinity and preferential face-on orientation in the blend film partially explain the superior photovoltaic performance achieved in PBDT(Se)-T1-based solar cells. The results indicate the important role of chalcogen atoms in conjugated side chains and that high photovoltaic performance can be realized through side chain engineering of BDT-based WBG conjugated polymers.</P>

Long-lived K isomer and enhanced γ vibration in the neutron-rich nucleus ¹⁷²Dy: Collectivity beyond double midshell

Watanabe, H.,Zhang, G.X.,Yoshida, K.,Walker, P.M.,Liu, J.J.,Wu, J.,Regan, P.H.,Soderstrom, P.A.,Kanaoka, H.,Korkulu, Z.,Lee, P.S.,Nishimura, S.,Yagi, A.,Ahn, D.S.,Alharbi, T.,Baba, H.,Browne, F.,Bruce North-Holland Pub. Co 2016 Physics letters. Section B Vol.760 No.-

The level structure of <SUP>172</SUP>Dy has been investigated for the first time by means of decay spectroscopy following in-flight fission of a <SUP>238</SUP>U beam. A long-lived isomeric state with T<SUB>½</SUB>=0.71(5) s and K<SUP>π</SUP>=8<SUP>-</SUP> has been identified at 1278 keV, which decays to the ground-state and γ-vibrational bands through hindered electromagnetic transitions, as well as to the daughter nucleus <SUP>172</SUP>Ho via allowed β decays. The robust nature of the K<SUP>π</SUP>=8<SUP>-</SUP> isomer and the ground-state rotational band reveals an axially-symmetric structure for this nucleus. Meanwhile, the γ-vibrational levels have been identified at unusually low excitation energy compared to the neighboring well-deformed nuclei, indicating the significance of the microscopic effect on the non-axial collectivity in this doubly mid-shell region. The underlying mechanism of enhanced γ vibration is discussed in comparison with the deformed Quasiparticle Random-Phase Approximation based on a Skyrme energy-density functional.

Investigation of PCR-RFLPs within Major Histocompatibility Complex B-G Genes Using Two Restriction Enzymes in Eight Breeds of Chinese Indigenous Chickens

R. F. Xu,K. Li,G. H. Chen,B. Y. Z. Qiang,D. L. Mo,B. Fan,C. C. Li,M. Yu,M. J. Zhu,T. A. Xiong,B. Liu 아세아·태평양축산학회 2005 Animal Bioscience Vol.18 No.7

New polymorphism of major histocompatibility complex B-G genes was investigated by amplification and digestion of a 401bp fragment including intron 1 and exon 2 using polymerase chain reaction-restriction fragment length polymorphism (PCRRFLP) technique with two restriction enzymes of Msp I and Tas I in eight breeds of Chinese indigenous chickens and one exotic breed. In the fragment region of the gene, three novel single nucleotide polymorphisms (SNPs) were detected at the two restriction sites. We found the transition of two nucleotides of A294G and T295C occurred at Tas I restriction site, and consequently led to a nonsynonymous substitution of asparagine into serine at position 54 within the deduced amino acid sequence of immunoglobulin variableregion- like domain encoded by the exon 2 of B-G gene. It was observed at rare frequency that a single mutation of A294G occurring at the site, also caused an identical substitution of amino acid, asparagine 54-to-serine, to that we described previously. And the transversion of G319C at Msp I site led to a non-synonymous substitution, glutamine 62-to-histidine. The new alleles and allele frequencies identified by the PCR-RFLP method with the two enzymes were characterized, of which the allele A and B frequencies at Msp I and Tas I loci were given disequilibrium distribution either in the eight Chinese local breeds or in the exotic breed. By comparison, allele A at Msp I locus tended to be dominant, while, the allele B at Tas I locus tended to be dominant in all of the breeds analyzed. In Tibetan chickens, the preliminary association analysis revealed that no significant difference was observed between the different genotypes identified at the Msp I and Tas I loci and the laying performance traits, respectively.

Cytoskeletal Patterns, In Vitro Maturation and Parthenogenetic Development of Rabbit GV Oocytes

Ju, J.C.,Chen, T.H.,Tseng, J.K.,Tsay, C.,Yeh, S.P.,Chou, P.C.,Chen, C.H.,Liu, C.T. Asian Australasian Association of Animal Productio 2002 Animal Bioscience Vol.15 No.12

The purposes of this study were to optimize the in vitro maturation (IVM) and culture (IVC) systems of rabbit oocytes. Cytoskeletal structures in the germinal vesicle stage (GV) and during IVM are also investigated. Ovaries were transported from local slaughterhouses and the cumulus-oocyte complexes (COCs) were collected from ovarian follicles (${\geq}1mm$). COCs were randomly allocated to TCM199-based medium ($T_1$, TCM-199) supplemented with $NaHCO_3$, glucose, sodium pyruvate and FSH ($T_2$), $T_2+E_2+LH$ ($T_3$), $T_3+FBS$ ($T_4$), or $T_1+E_2+LH+FSH+FBS$ ($T_5$), for IVM. In Experiment 1, COCs were retrieved from the follicles and 51 GV oocytes were fixed in the fixative (MTSB-XF) for nuclear and cytoplasmic examinations. In Experiment 2, progressive changes of both the nucleus and the cytoskeleton were examined at 0, 6, 16, and 20 h after IVM. Maturation (MR) and developmental rates were assessed in Experiment 3. Cytoplasmic microtubules (MT) were clearly observed in rabbit GV oocytes. To our knowledge, this is the first report that describes the appearance of MT structures in the GV stage ooplasm. Tremendous variations in cytoskeletal alterations were observed among treatments with the exception of the vitelline ring (VR), which is constantly visible and unchanged during maturation. Germinal vesicle breakdown (GVBD) does not occur at 6 h after onset of maturation culture. When the oocytes for IVM were collected within 2 h, results from Experiment 3 showed that rates of nuclear maturation were 42, 8, 42, 37 and 65% at 16 h of IVM for $T_1$ through $T_5$, respectively, in which $T_1$, $T_4$ and $T_5$ had significantly greater MR than those in other groups (p<0.05). Morula/blastocyst development after parthenogenetic activation ranged from 20 to 63% with significantly greater rates in $T_3$, $T_4$ and $T_5$ (p<0.05). These results suggested that oocytes recovered from slaughterhouse ovaries can be matured and parthenogenetically activated in vitro, but the MR remained low in this study. Addition of $E_2$ and LH in the medium may be beneficial for cytoplasmic maturation, but FBS exerts a nega- tive role in the subsequent development of parthenogenetic embryos when energy substrates are provided in the IVC media. More studies are required for improving the MR and further development of the GV stage rabbit oocytes.

Exchange coupling in ferromagnetic/antiferromagnetic/ferromagnetic [Pd/Co]_<i>n</i>/NiO/Co trilayers with different [Pd/Co] anisotropy

Yu, T.,Ning, X.K.,Liu, W.,Feng, J.N.,Kim, D.,Choi, C.J.,Zhang, Z.D. Elsevier 2015 Journal of magnetism and magnetic materials Vol.385 No.-

<P><B>Abstract</B></P> <P>Exchange coupling in NiO/Co bilayers and [Pd/Co(<I>t</I> <SUB> <I>Co</I> </SUB>)]<SUB> <I>n</I> </SUB>/NiO/Co trilayers prepared by magnetron sputtering has been investigated. With decreasing thickness (<I>t</I> <SUB> <I>Co</I> </SUB>) of the Co layers in [Pd/Co] multilayers (MLs) and increasing number of [Pd/Co] repeats (<I>n</I>), the ferromagnetic easy axis of the [Pd/Co] MLs switches from in-plane to out-of-plane direction. Ferromagnetic and non-collinear interlayer couplings between the [Pd/Co] MLs and the Co layer across the antiferromagnetic NiO spacer are found in trilayers. After cooling at in-plane and out-of-plane remanent state, respectively, for <I>t</I> <SUB> <I>Co</I> </SUB>=1nm and <I>n</I>=2, a larger in-plane exchange bias field of 724Oe is observed which vanishes at temperatures above 90K which is the same as the in-plane blocking temperature observed in the NiO/Co bilayer. For <I>t</I> <SUB> <I>Co</I> </SUB>=0.3nm and <I>n</I>=7, the in-plane blocking temperature in the trilayer enhances up to 210K, which strongly depends on orientation and strength of the ferromagnetic [Pd/Co] ML anisotropy axis.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The easy axis of the [Pd/Co] MLs switches from in-plane to out-of-plane direction. </LI> <LI> Ferromagnetic and non-collinear interlayer couplings are found in the trilayers. </LI> <LI> A larger in-plane <I>H</I> <SUB> <I>E</I> </SUB> of 724Oe is observed for the trilayers <I>t</I> <SUB> <I>Co</I> </SUB>=1nm and <I>n</I>=2. </LI> <LI> The in-plane blocking temperature <I>T</I> <SUB> <I>B</I> </SUB> increases up to 210K for <I>t</I> <SUB> <I>Co</I> </SUB>=0.3nm and <I>n</I>=7. </LI> </UL> </P>

Hymenobacter daecheongensis sp. nov., isolated from stream sediment

Xu, J.-L.,Liu, Q.-M.,Yu, H.-S.,Jin, F.-X.,Lee, S.-T.,Im, W.-T. Microbiology Society 2009 International journal of systematic and evolutiona Vol.59 No.5

<P>A Gram-negative, strictly aerobic, non-spore-forming, rod-shaped, red-pink bacterium, designated strain Dae14(T), was isolated from stream sediment collected near Daecheong Dam, South Korea, and its taxonomic position was investigated by using a polyphasic approach. Phylogenetic analysis of 16S rRNA gene sequences showed that strain Dae14(T) belonged to the genus Hymenobacter. Sequence similarities between strain Dae14(T) and the type strains of Hymenobacter species with validly published names ranged from 91.3 to 94.3 %. The predominant cellular fatty acids of strain Dae14(T) were iso-C(15 : 0), C(16 : 1)omega5c, summed feature 5 (iso-C(17 : 1) I and/or anteiso-C(17 : 1) B) and iso-C(16 : 0). The DNA G+C content was 62.2 mol%. Results of phylogenetic, chemotaxonomic and phenotypic characterization indicated that strain Dae14(T) can be distinguished from all known Hymenobacter species and represents a novel species, for which the name Hymenobacter daecheongensis sp. nov. is proposed, with Dae14(T) (=KCTC 22258(T)=LMG 24498(T)) as the type strain.</P>

Combining metabolic engineering and biocompatible chemistry for high-yield production of homo-diacetyl and homo-(S,S)-2,3-butanediol

Liu, J.,Chan, S.H.J.,Brock-Nannestad, T.,Chen, J.,Lee, S.Y.,Solem, C.,Jensen, P.R. Academic Press 2016 Metabolic engineering Vol.36 No.-

Biocompatible chemistry is gaining increasing attention because of its potential within biotechnology for expanding the repertoire of biological transformations carried out by enzymes. Here we demonstrate how biocompatible chemistry can be used for synthesizing valuable compounds as well as for linking metabolic pathways to achieve redox balance and rescued growth. By comprehensive rerouting of metabolism, activation of respiration, and finally metal ion catalysis, we successfully managed to convert the homolactic bacterium Lactococcus lactis into a homo-diacetyl producer with high titer (95mM or 8.2g/L) and high yield (87% of the theoretical maximum). Subsequently, the pathway was extended to (S,S)-2,3-butanediol (S-BDO) through efficiently linking two metabolic pathways via chemical catalysis. This resulted in efficient homo-S-BDO production with a titer of 74mM (6.7g/L) S-BDO and a yield of 82%. The diacetyl and S-BDO production rates and yields obtained are the highest ever reported, demonstrating the promising combination of metabolic engineering and biocompatible chemistry as well as the great potential of L. lactis as a new production platform.