Structural characterization of the pulmonary innate immune protein SPLUNC1 and identification of lipid ligands

Ning, Fangkun,Wang, Chao,Berry, Karin Zemski,Kandasamy, Pitchaimani,Liu, Haolin,Murphy, Robert C.,Voelker, Dennis R.,Nho, Chu Won,Pan, Choel-Ho,Dai, Shaodong,Niu, Liwen,Chu, Hong-Wei,Zhang, Gongyi The Federation of American Societies for Experimen 2014 The FASEB Journal Vol.28 No.12

<P>The short palate, lung and nasal epithelial clone 1 (SPLUNC1) protein is a member of the palate, lung, and nasal epithelium clone (PLUNC) family, also known as bactericidal/permeability-increasing (BPI) fold-containing protein, family A, member 1 (BPIFA1). SPLUNC1 is an abundant protein in human airways, but its function remains poorly understood. The lipid ligands of SPLUNC1 as well as other PLUNC family members are largely unknown, although some reports provide evidence that lipopolysaccharide (LPS) could be a lipid ligand. Unlike previous hypotheses, we found significant structural differences between SPLUNC1 and BPI. Recombinant SPLUNC1 produced in HEK 293 cells harbored several molecular species of sphingomyelin and phosphatidylcholine as its ligands. Significantly, <I>in vitro</I> lipid-binding studies failed to demonstrate interactions between SPLUNC1 and LPS, lipoteichoic acid, or polymyxin B. Instead, one of the major and most important pulmonary surfactant phospholipids, dipalmitoylphosphatidylcholine (DPPC), bound to SPLUNC1 with high affinity and specificity. We found that SPLUNC1 could be the first protein receptor for DPPC. These discoveries provide insight into the specific determinants governing the interaction between SPLUNC1 and lipids and also shed light on novel functions that SPLUNC1 and other PLUNC family members perform in host defense.—Ning, F., Wang, C., Berry, K. Z., Kandasamy, P., Liu, H., Murphy, R. C., Voelker, D. R., Nho, C. W., Pan, C.-H., Dai, S., Niu, L., Chu, H.-W., Zhang, G. Structural characterization of the pulmonary innate immune protein SPLUNC1 and identification of lipid ligands.</P>

Continuous Passaging of a Recombinant C-Strain Virus in PK-15 Cells Selects Culture-Adapted Variants that Showed Enhanced Replication but Failed to Induce Fever in Rabbits

( Chao Tong ),( Ning Chen ),( Xun Liao ),( Xuemei Yuan ),( Mengjiao Sun ),( Xiaoliang Li ),( Weihuan Fang ) 한국미생물생명공학회(구 한국산업미생물학회) 2017 Journal of microbiology and biotechnology Vol.27 No.9

Classical swine fever virus (CSFV) is the etiologic agent of classical swine fever, a highly contagious disease that causes significant economic losses to the swine industry. The lapinized C-strain, a widely used vaccine strain against CSFV, has low growth efficiency in cell culture, which limits the productivity in the vaccine industry. In this study, a recombinant virus derived from C-strain was constructed and subjected to continuous passaging in PK-15 cells with the goal of acquiring a high progeny virus yield. A cell-adapted virus variant, RecCpp80, had nearly 1,000-fold higher titer than its parent C-strain but lost the ability to induce fever in rabbits. Sequence analysis of cell-adapted RecC variants indicated that at least six nucleotide changes were fixed in RecCpp80. Further adaption of RecCpp80 variant in swine testicle cells led to a higher virus yield without additional mutations. Introduction of each of these residues into the wild-type RecC backbone showed that one mutation, M979R (T3310G), located in the C-terminal region of E2 might be closely related to the cell-adapted phenotype. Rabbit inoculation revealed that RecCpp80+10 failed to induce fever in rabbits, whereas RecCpp40₊₁₀ caused a fever response similar to the commercial C-strain vaccine. In conclusion, the C-strain can be adapted to cell culture by introducing specific mutations in its E2 protein. The mutations in RecCpp80 that led to the loss of fever response in rabbits require further investigation. Continuous passaging of the C-strain-based recombinant viruses in PK-15 cells could enhance its in vitro adaption. The non-synonymous mutations at 3310 and 3531 might play major roles in the enhanced capacity of general virus reproduction. Such findings may help design a modified C-strain for improved productivity of commercial vaccines at reduced production cost.

The Epitope Recognized by Monoclonal Antibody 2B6 in the B/C Domains of Classical Swine Fever Virus Glycoprotein E2 Affects Viral Binding to Hyperimmune Sera and Replication

( Chao Tong ),( Ning Chen ),( Xun Liao ),( Wen Qi Xie ),( De Jiang Li ),( Xiao Liang Li ),( Wei Huan Fang ) 한국미생물 · 생명공학회 2015 Journal of microbiology and biotechnology Vol.25 No.4

Classical swine fever (CSF) is a highly contagious disease of pigs caused by CSF virus (CSFV). E2 is the major viral envelope protein of immune dominance that induces neutralizing antibodies and confers protection against CSFV infection. The B/C domains of E2 are variable among CSFV isolates, which could affect immunogenicity and binding to antibodies. We attempted to characterize the epitope recognized by a monoclonal antibody 2B6 (mAb-2B6) raised against the E2 B/C domains of the vaccine C-strain and to examine if mutations in the epitope region would affect antibody binding and viral neutralization. The epitope specific for mAb-2B6 recognition is linear, spanning five residues 774DGXNP778 in the B/C domains. The residue N777 is indispensable for the specificity. The epitope exists only in group 1 strains, but not in those of group 2. The recombinant viruses containing individual mutations on the epitope region lost the reactivity to mAb-2B6. The mutant virus RecC-N777S had low replication potential, about 10-fold decrease in the yield of progeny virus particles, whereas the mutant virus RecC-P778A reverted to proline upon continuous passaging. The mutations on the mAb-2B6 epitope region did not affect neutralization by anti-C-strain polyclonal sera from pigs. Deletion from aa774 covering the mAb-2B6 epitope, but not that from aa781, also affected binding with the polyclonal antibodies from vaccinated pigs, although the major binding region for the vaccinated antibodies is aa690-773.

Shaking Table Test on Seismic Responses of a Monolithic Precast Concrete Shear Wall Structure

Chao-gang Qin,Guoliang Bai,Ya-zhou Xu,Ning Fen Su,Tao Wu,Zhong Liang Li,Yu Zhe Sun 대한토목학회 2018 KSCE Journal of Civil Engineering Vol.22 No.10

To examine the seismic performance of Monolithic Precast Concrete Shear Wall (MPCSW) structure, a 1/5-scaled twelve-story model is designed and investigated by shaking table test, and connections between the precast elements and their impact on seismic performance of the overall model are comprehensively inspected and analyzed. Based on the testing results, the structural responses are divided into elastic stage and plastic stage, and the variations of dynamic characteristics, cracking and failure pattern, seismic responses of the model are accordingly presented. The experimental results indicate that most of critical cracks of the MPCSW model locate on the coupling beams and horizontal connections of precast concrete shear walls, and the fundamental frequency exhibits a successively decreasing trend during the entire testing process. Furthermore, The MPCSW model is designed in accordance with Chinese codes meets the requirement for the seismic fortification intensity of eight, and shows an adequate safety margin to resist collapse in the case of 0.90 g.

Experimental and Numerical Researches on the Seismic Behavior of Tubular Reinforced Concrete Columns of Air-Cooling Structures

Ning-jun Du,Guo-liang Bai,Ya-zhou Xu,Chao-gang Qin 한국콘크리트학회 2017 International Journal of Concrete Structures and M Vol.11 No.3

Tubular reinforced concrete columns of air-cooling condenser structures, which undertake the most weight of air cooling equipment, are the major components to resist lateral forces under earthquake. Once collapsed, huge casualties and economic loss would be caused. Thus, four 1/8 scaled specimens were fabricated and tested through the pseudo-static testing method. Failure modes and crack patterns of the specimens under cyclic loading were observed. Then, finite element models of tubular reinforced concrete columns were established using OpenSees and were verified with the experimental results. Finally, the influence of axial compression ratio and longitudinal reinforcement on energy dissipation capacity and stiffness degradation were studied based on the validated finite element modes. It is confirmed that tubular reinforced concrete columns of air-cooling condenser structure exhibit a moderate ability of energy dissipation, and the nonlinear finite element model could reasonably simulate its seismic behavior. Furthermore, axial compression ratio and longitudinal reinforcement are main factors which affect the seismic behavior of the tubular reinforced concrete columns. The experimental results and simulation method provide an available way to design this kind of large tubular reinforced concrete columns with thin-wall.

An Error Quasi Quadratic Differential Based Event-triggered MPC for Continuous Perturbed Nonlinear Systems

Ning He,Qingqing Chen,Zhongxian Xu,Botao Bai,Chao Shen 제어·로봇·시스템학회 2024 International Journal of Control, Automation, and Vol.22 No.1

A new event-triggered model predictive control (ET-MPC) algorithm is proposed for continuous perturbed nonlinear systems with constraints for the purpose of reducing computing burden and communication transmission. In the first step, an original event triggering condition is constructed based on the slope variation of the state error between the optimal prediction and the real state, i.e., the quasi quadratic differential (QQD) type eventtriggered mechanism. Secondly, the dual-mode control has been adopted to deal with the constrained nonlinear systems subject to disturbances, based on which the execution process of the proposed QQD based ET-MPC is described. In addition, the feasibility of the algorithm and closed-loop stability of the system have been strictly proved in theory. Lastly, two simulation examples are utilized to verify the effectiveness and applicability of the proposed algorithm.

Construction of a Protein-Protein Interaction Network for Chronic Myelocytic Leukemia and Pathway Prediction of Molecular Complexes

Zhou, Chao,Teng, Wen-Jing,Yang, Jing,Hu, Zhen-Bo,Wang, Cong-Cong,Qin, Bao-Ning,Lv, Qing-Liang,Liu, Ze-Wang,Sun, Chang-Gang Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.13

Background: Chronic myelocytic leukemia is a disease that threatens both adults and children. Great progress has been achieved in treatment but protein-protein interaction networks underlining chronic myelocytic leukemia are less known. Objective: To develop a protein-protein interaction network for chronic myelocytic leukemia based on gene expression and to predict biological pathways underlying molecular complexes in the network. Materials and Methods: Genes involved in chronic myelocytic leukemia were selected from OMIM database. Literature mining was performed by Agilent Literature Search plugin and a protein-protein interaction network of chronic myelocytic leukemia was established by Cytoscape. The molecular complexes in the network were detected by Clusterviz plugin and pathway enrichment of molecular complexes were performed by DAVID online. Results and Discussion: There are seventy-nine chronic myelocytic leukemia genes in the Mendelian Inheritance In Man Database. The protein-protein interaction network of chronic myelocytic leukemia contained 638 nodes, 1830 edges and perhaps 5 molecular complexes. Among them, complex 1 is involved in pathways that are related to cytokine secretion, cytokine-receptor binding, cytokine receptor signaling, while complex 3 is related to biological behavior of tumors which can provide the bioinformatic foundation for further understanding the mechanisms of chronic myelocytic leukemia.

Preoperative body mass index and amylase level predict postoperative pancreatic fistula independently

Deng NING,Li JIANG,Xiaoping CHEN,Chao WANG 한국간담췌외과학회 2021 Annals of hepato-biliary-pancreatic surgery Vol.25 No.-

Bright all-solution-processed CsPbBr3 perovskite light emitting diodes optimized by quaternary ammonium salt

Liu Ning,You Fangtian,Ji Chao,Gong Hongkang,Song Qi,Li Jiasen,Liang Chunjun,He Zhiqun 한국물리학회 2021 Current Applied Physics Vol.31 No.-

Perovskite light-emitting diodes (PeLEDs) prepared by the all-solution-process are gradually coming into view due to their low cost and flexible production process. However, the performance of CsPbBr3 device is limited by the high non-radiative recombination losses due to incomplete surface coverage and grain defects. Here a quaternary ammonium salt, tetrabutylammonium hexafluorophosphate (TBA-PF6) was simultaneously introduced into perovskite emission layers (CsPbBr3) and electron transport layer (TPBi (1,3,5-Tris(1-phenyl-1Hbenzimidazol- 2-yl) benzene) dissolved in ethyl acetate). As a result, the morphology and luminescence of CsPbBr3 films were improved, and the energy level of TPBi was more conducive to charge transport. Consequently, the maximum luminance and current efficiency of the modified green-emitting PeLEDs are improved. Furthermore, the optimized device had an operating life of more than 20 min at an initial luminance of 1230 cd/ m2. This work provides a simple and easy method to be scaled up for the development of low-cost all-solutionprocessed PeLEDs.

An Aligned Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) Scaffold Fixed with Fibronectin to Enhance the Attachment and Growth of Human Endothelial Progenitor Cells

Chien-Ning Hsu,Ya-Ting Lin,Yu-Hsu Chen,Tsung-Yu Tseng,Hsing-Fen Tsai,Shinn-Gwo Hong,Chao-Ling Yao 한국생물공학회 2023 Biotechnology and Bioprocess Engineering Vol.28 No.3

Repair and regeneration of vascular tissue is a crucial current research focus in the fields of biomedical engineering and regenerative medicine. Numerous studies revealed that cells are required to grow on an appropriate extracellular matrix to maintain or enhance functionality. In the present study, various surface modification methods were evaluated to fix fibronectin on the surface of a bio-based and aligned poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) film for vascular tissue engineering. After chemical modification, the properties of the fibronectin-fixed PHBV films were examined and compared with the original films, including -NH2 group expression, contact angle, mechanical properties, and fibronectin binding amount. Then, cytotoxicity and biocompatibility were measured by culture with L929 cells and endothelial progenitor cells (EPCs) of the fibronectinfixed PHBV films. In addition, cell morphology, cell growth kinetics, acetylated low-density lipoprotein uptake ability, lectin binding ability and specific gene expressions of cultured EPCs on fibronectin-fixed PHBV films were also analyzed. Taken together, our data demonstrated that the surface of the aligned PHBV films could be successfully modified to immobilize fibronectin. Importantly, EPCs cultured on the fibronectin-fixed PHBV films showed excellent cell biocompatibility, a rapid proliferation rate, an aligned growth direction and correct cell functions. We believed that fibronectin-fixed PHBV films can serve as a potential scaffold for vascular tissue engineering.