30 research outputs found
Effect of different trunk postures on scapular muscle activities and kinematics during shoulder external rotation
[Background]Shoulder external rotation at abduction (ER) is a notable motion in overhead sports because it could cause strong stress to the elbow and shoulder joint. However, no study has comprehensively investigated the effect of different trunk postures during ER. This study aimed to investigate the effect of different trunk postures on scapular kinematics and muscle activities during ER. [Methods]Fourteen healthy men performed active shoulder external rotation at 90° of abduction with the dominant arm in 15 trunk postures. At maximum shoulder external rotation in 15 trunk postures, including 4 flexion-extension, 6 trunk rotation, and 4 trunk side-bending postures, as well as upright posture as a control, scapular muscle activities and kinematics were recorded using surface electromyography and an electromagnetic tracking device, respectively. The data obtained in the flexion-extension, trunk rotation, and trunk side-bending postures were compared with those obtained in the upright posture. [Results]In the flexion-extension condition, scapular posterior tilt and external rotation significantly decreased, but the muscle activities of the lower trapezius and infraspinatus significantly increased in maximum trunk flexion. Moreover, scapular upward rotation and the activity of the serratus anterior significantly increased in maximum trunk extension. In the rotation condition, scapular posterior tilt and external rotation significantly decreased, but the activity of the serratus anterior significantly increased in the maximum contralateral trunk rotation posture. In the trunk side-bending condition, scapular posterior tilt and the external rotation angle significantly decreased. [Conclusio]Trunk postures affected scapular kinematics and muscle activities during ER. Our results suggest that different trunk postures activate the lower trapezius and serratus anterior, which induce scapular posterior tilt
Cross-Protective Peptide Vaccine against Influenza A Viruses Developed in HLA-A*2402 Human Immunity Model
Background: The virus-specific cytotoxic T lymphocyte (CTL) induction is an important target for the development of a broadly protective human influenza vaccine, since most CTL epitopes are found on internal viral proteins and relatively conserved. In this study, the possibility of developing a strain/subtype-independent human influenza vaccine was explored by taking a bioinformatics approach to establish an immunogenic HLA-A24 restricted CTL epitope screening system in HLAtransgenic mice. Methodology/Principal Findings: HLA-A24 restricted CTL epitope peptides derived from internal proteins of the H5N1 highly pathogenic avian influenza A virus were predicted by CTL epitope peptide prediction programs. Of 35 predicted peptides, six peptides exhibited remarkable cytotoxic activity in vivo. More than half of the mice which were subcutaneously vaccinated with the three most immunogenic and highly conserved epitopes among three different influenza A virus subtypes (H1N1, H3N2 and H5N1) survived lethal influenza virus challenge during both effector and memory CTL phases. Furthermore, mice that were intranasally vaccinated with these peptides remained free of clinical signs after lethal virus challenge during the effector phase. Conclusions/Significance: This CTL epitope peptide selection system can be used as an effective tool for the development of a cross-protective human influenza vaccine. Furthermore this vaccine strategy can be applicable to the development o
Emulsified Phosphatidylserine, Simple and Effective Peptide Carrier for Induction of Potent Epitope-Specific T Cell Responses
<div><p>Background</p><p>To induce potent epitope-specific T cell immunity by a peptide-based vaccine, epitope peptides must be delivered efficiently to antigen-presenting cells (APCs) <i>in vivo</i>. Therefore, selecting an appropriate peptide carrier is crucial for the development of an effective peptide vaccine. In this study, we explored new peptide carriers which show enhancement in cytotoxic T lymphocyte (CTL) induction capability.</p> <p>Methodology/Principal Findings</p><p>Data from an epitope-specific <i>in vivo</i> CTL assay revealed that phosphatidylserine (PS) has a potent adjuvant effect among candidate materials tested. Further analyses showed that PS-conjugated antigens were preferentially and efficiently captured by professional APCs, in particular, by CD11c<sup>+</sup>CD11b<sup>+</sup>MHCII<sup>+</sup> conventional dendritic cells (cDCs) compared to multilamellar liposome-conjugates or unconjugated antigens. In addition, PS demonstrated the stimulatory capacity of peptide-specific helper T cells <i>in vivo</i>.</p> <p>Conclusions/Significance</p><p>This work indicates that PS is the easily preparable efficient carrier with a simple structure that delivers antigen to professional APCs effectively and induce both helper and cytotoxic T cell responses <i>in vivo</i>. Therefore, PS is a promising novel adjuvant for T cell-inducing peptide vaccines.</p> </div
Mice immunized with PS-conjugated peptide induced epitope-specific CTL effectively <i>in vivo</i>.
<p>(A) B6 mice (3 to 4 mice per group) were immunized s.c. with each carrier-conjugated NP<sub>366–374</sub> (A/HK483) peptide or peptide without carrier in the presence of poly(I:C). Seven days after the immunization, bright CFSE-labeled target cells pulsed with peptide used for the immunization and dim CFSE-labeled target cells pulsed with an irrelevant peptide were injected i.v. as an <i>in vivo</i> cytotoxicity assay. Viability of the target cells in the spleen was examined 20 h after injection. Reduction ratios of epitope-specific target cells were calculated using the formula described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0060068#s2" target="_blank">Materials and Methods</a>. (B) A24Tg mice (3 mice per group) were inoculated with PS- or liposome-conjugated NP<sub>257–264</sub> (A/HK483) peptide. The <i>in vivo</i> cytotoxicity assay was performed as described for <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0060068#pone-0060068-g001" target="_blank">Figure 1A</a>. n.s. indicates not significant. *p<0.01, **p<0.0001.</p
PS-conjugated Ags were captured by professional APCs effectively.
<p>(A) Splenocytes were classified into five subpopulations (I to V) based on the expression pattern of CD11b and CD11c. I:CD11b<sup>−</sup>CD11c<sup>−</sup> cells, II:CD11b<sup>int</sup>CD11c<sup>−</sup> cells, III:CD11b<sup>high</sup>CD11c<sup>−</sup> cells, IV:CD11b<sup>+</sup>CD11c<sup>+</sup> cells, V:CD11b<sup>−</sup>CD11c<sup>+</sup> cells. (B, C) Each isolated population was co-cultured with sfGFP, sfGFP-PS or sfGFP-liposome for 60 min, and then the amount of uptake was analyzed by flow cytometry. (D, E) Each population of isolated cells was co-cultured with DQ-OVA or DQ-OVA-PS for 60 min, and then the efficiency of antigen degradation processing was analyzed by flow cytometry.</p
CD11c<sup>+</sup>CD11b<sup>+</sup> cells are main APCs in peptide vaccines.
<p>The five kinds of sorted splenocytes were activated with CpG5002 <i>in vitro</i> and cultured with CD8<sup>+</sup> T cells from NP<sub>366–374</sub>-PS immunized mice with serial dilutions of PS-conjugated NP<sub>366–374</sub> peptide for 2 days. Proliferation of NP<sub>366–374</sub>-specific CD8<sup>+</sup> cells was measured by BrdU uptake. The experiment was repeated twice with similar results. *p<0.05, **p<0.01.</p
Frequency of epitope-specific CD8<sup>+</sup> T cells in immunized mice.
<p>(A) PS-conjugated NP<sub>366–374</sub> (A/PR8) peptide, PS-conjugated OVA<sub>257–264</sub> peptide or unconjugated peptide was inoculated into B6 mice (3 to 4 mice per group). The <i>in vivo</i> cytotoxicity assay was performed as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0060068#pone-0060068-g001" target="_blank">Figure 1</a>. *p<0.01, **p<0.0001. (B) Splenocytes from naïve mice and mice immunized with PS-conjugated or unconjugated peptide in the presence of poly(I:C) were stained with tetramer and anti-mouse CD8 Ab. The percentage indicates the tetramer-positive cells in total CD8<sup>+</sup> cells. The experiment was repeated three times with similar results.</p
Proliferation assay of epitope-specific helper T cells.
<p>CD4<sup>+</sup> T cells from mice immunized with PS-conjugated or unconjugated peptide were co-cultured with activated BMDCs for 2 days in complete RPMI medium containing the indicated concentration of NP<sub>311–325</sub> peptide. Proliferation of NP<sub>311–325</sub>-specific CD4<sup>+</sup> Th cells was measured by BrdU uptake. The experiment was repeated three times with similar results. *p<0.05, **p<0.005</p
Confocal laser scanning microscopy analysis of splenocytes co-cultured with PS-conjugated antigens.
<p>(A, B) CD11b<sup>+</sup> or CD11c<sup>+</sup> cells were cultured with sfGFP, sfGFP-PS, DQ-OVA or DQ-OVA-PS plus Hoechst33342 for 60 min at 37°C. After the incubation, cells were washed with PBS, and then analyzed under a LSM780 confocal laser scanning microscope system. Blue: cell nucleus, Green: sfGFP or DQ-OVA, Red: CD11b or CD11c.</p