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Hypoxia is a key hallmark of solid tumors and can cause resistance to various treatments such as photodynamics and immunotherapy. Microenvironment-responsive gene editing provides a powerful tool to overcome hypoxia resistance and remodel hypoxic microenvironments for enhanced tumor therapy. Here, a light-enhanced hypoxia-responsive multifunctional nanocarrier is developed to perform spatiotemporal specific dual gene editing for enhanced photodynamic and immunotherapy in breast cancer. As a gated molecule of nanocarrier, the degradation of azobenzene moieties under hypoxic conditions triggers controllable release of Cas9 ribonucleoprotein in hypoxic site of the tumor. Hyaluronic acid is conjugated with chloramine e6 to coat mesoporous silica nanoparticles for targeted delivery in tumors and generation of high levels of reactive oxygen species, which can result in increased hypoxia levels for effective cleavage of azobenzene bonds to improve gene editing efficiency and reduce toxic side effects with light irradiation. Moreover, dual targeting HIF-1α and PD-L1 in the anoxic microenvironments can overcome hypoxia resistance and remodel immune microenvironments, which reduces tumor plasticity and resistance to photodynamic and immunotherapy. In summary, a light-enhanced hypoxia responsive nanocomposite is developed for controllable gene editing which holds great promise for synergistic hypoxia-resistant photodynamic and immunotherapy., (© 2023 Wiley-VCH GmbH.)

CRISPR system-assisted immunotherapy is an attractive option in cancer therapy. However, its efficacy is still less than expected due to the limitations in delivering the CRISPR system to target cancer cells. Here, we report a new CRISPR/Cas9 tumor-targeting delivery strategy based on bioorthogonal reactions for dual-targeted cancer immunotherapy. First, selective in vivo metabolic labeling of cancer and activation of the cGAS-STING pathway was achieved simultaneously through tumor microenvironment (TME)-biodegradable hollow manganese dioxide (H-MnO 2 ) nano-platform. Subsequently, CRISPR/Cas9 system-loaded liposome was accumulated within the modified tumor tissue through in vivo click chemistry, resulting in the loss of protein tyrosine phosphatase N2 (PTPN2) and further sensitizing tumors to immunotherapy. Overall, our strategy provides a modular platform for precise gene editing in vivo and exhibits potent antitumor response by boosting innate and adaptive antitumor immunity., (© 2023 Wiley-VCH GmbH.)

Background: Idiopathic pulmonary fibrosis (IPF) is a progressive chronic interstitial lung disease with limited therapeutic options. Cuproptosis is a recently proposed novel form of programmed cell death, which has been strongly implicated in the development of various human diseases. However, the prognostic and therapeutic value of cuproptosis-related genes (CRGs) in IPF remains to be elucidated., Methods: In the present study, weighted gene co-expression network analysis (WGCNA) was employed to identify the key CRGs associated with the development of IPF. The subsequent GSEA, immune cell correlation analysis, and single-cell RNA-Seq analysis were conducted to explore the potential role of the identified CRGs in IPF. In addition, ROC curves and survival analysis were used to assess the prognostic value of the key CRGs in IPF. Moreover, we explored the molecular mechanisms of participation of identified key CRGs in the development of pulmonary fibrogenesis through in vivo and in vitro experiments., Results: The expression level of cyclin-dependent kinase inhibitor 2A (CDKN2A) is upregulated in the lung tissues of IPF patients and associated with disease severity. Notably, CDKN2A was constitutively expressed by fibrosis-promoting M2 macrophages. Decreased CDKN2A expression sensitizes M2 macrophages to elesclomol-induced cuproptosis in vitro. Inhibition of CDKN2A decreases the number of viable macrophages and attenuates bleomycin-induced pulmonary fibrosis in mice., Conclusion: These findings indicate that CDKN2A mediates the resistance of fibrosis-promoting M2 macrophages to cuproptosis and promotes pulmonary fibrosis in mice. Our work provides fresh insights into CRGs in IPF with potential value for research in the pathogenesis, diagnosis, and a new therapy strategy for IPF., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

CRISPR, as an emerging gene-editing technology, has been widely used in multidisciplinary fields, including genetic diseases and some cancers. However, it remains a challenge to efficiently deliver CRISPR for safe and efficient genome editing. Currently, biomimetic materials have become an attractive delivery strategy for CRISPR-mediated genome editing due to their low immunogenicity and application safety. The biomimetic materials delivery is involved in the improvement of cellular uptake of nanoparticle vectors, and the gene editing efficiency. In this review, we summarize the current delivery strategies of CRISPR/Cas systems based on biogenic materials such as viruses, bacteria, cells, bioactive substances, etc ., focusing on the potential applications in disease research and therapy. Finally, the prospects and limitations of CRISPR-based systems in therapeutics are discussed.

Multidrug resistance in cancer stem cells (CSCs) is a major barrier to chemotherapy; hence, developing CSC-specific targeted nanocarriers for efficient drug delivery is critical. In this study, monodisperse hollow-structured MnO 2 (H-MnO 2 ) with a mesoporous shell was created for efficient targeted drug delivery. An effective therapeutic compound isoliquiritigenin (ISL) was confirmed to inhibit the lung cancer stem-cell phenotype by natural compound screening based on integrated microfluidic devices. The resultant H-MnO 2 showed a high drug-loading content of the potent CSC-targeting compound ISL and near-infrared fluorescent dye indocyanine green (ICG). In addition, H-MnO 2 was successively modified with hyaluronic acid (HA) to enhance targeting CSCs with high CD44 expression levels. The H-MnO 2 @(ICG + ISL)@HA nanocomposites displayed promising chemotherapeutic and photothermal treatment capabilities, as well as NIR-triggered drug release, which showed excellent CSC-killing effects and tumor inhibition efficacy. Meanwhile, the development of the tumor was effectively restrained by NIR-triggered phototherapy and prominent chemotherapy without obvious side effects after tail vein injection of the nanocomposites in vivo. In summary, the prepared nanocomposites accomplished synergistic cancer therapy that targets CSCs, offering a versatile platform for lung cancer diagnosis and treatment.

Dysregulated endocrine hormones (EHs) contribute to tumorigenesis, but how EHs affect the tumor immune microenvironment (TIM) and the immunotherapy of non-small cell lung cancer (NSCLC) is still unclear. Here, endogenous ouabain (EO), an adrenergic hormone, is elevated in patients with NSCLC and closely related to tumor pathological stage, metastasis, and survival. EO promotes the suppression of TIM in vivo by modulating the expression of immune checkpoint proteins, in which programmed cell death protein ligand 1 (PD-L1) plays a major role. EO increases PD-L1 transcription; however, the EO receptor Na- and K-dependent adenosine triphosphatase (Na, K-ATPase) α1 interacts with PD-L1 to trigger the endocytic degradation of PD-L1. This seemingly contradictory result led us to discover the mechanism whereby EO cooperates with Na, K-ATPase α1 to finely control PD-L1 expression and dampen tumoral immunity. In conclusion, the Na, K-ATPase α1/EO signaling facilitates immune escape in lung cancer, and manipulation of this signaling shows great promise in improving immunotherapy for lung adenocarcinoma.

Optically pumped nuclear magnetic resonance (NMR) gyroscope has been widely concerned as a future gyroscope with great development potential. In this study, the Rb-Xe coupling effect in this gyroscope between the alkali metal magnetometer and the noble gas NMR is investigated. The theoretical formulae about this effect are obtained based on Bloch equation and demonstrated by experiments. In order to see the influence of this effect on the gyro signal, the Xe NMR frequency changes with the carrier frequency and demodulation phase of the Rb magnetometer are studied with the deduced formulae. More importantly, theoretical analysis shows that this coupling effect can also significantly reduce the efficiency of the dual species scheme, which is used to suppress the influence of magnetic fluctuation. Therefore, to remove the Rb-Xe coupling effect, a simple and preliminary decoupling scheme operated by locking the phase difference to zero is proposed and demonstrated. All this work is of great significance to the improvement of the NMR gyro performance and future applications., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier Inc.)

Axisymmetric resonators are key elements of Coriolis vibratory gyroscopes (CVGs). The performance of a CVG is closely related to the stiffness and damping symmetry of its resonator. The stiffness symmetry of a resonator can be effectively improved by electrostatic tuning or mechanical trimming, both of which need an accurate knowledge of the azimuth angles of the two stiffness axes of the resonator. Considering that the motion of a non-ideal axisymmetric resonator can be decomposed as two principal oscillations with two different natural frequencies along two orthogonal stiffness axes, this paper introduces a novel high-precision method of stiffness axes identification. The method is based on measurements of the phase difference between the signals detected at two orthogonal sensing electrodes when an axisymmetric resonator is released from all the control forces of the force-to-rebalance mode and from different initial pattern angles. Except for simplicity, our method works with the eight-electrodes configuration, in no need of additional electrodes or detectors. Furthermore, the method is insensitive to the variation of natural frequencies and operates properly in the cases of either large or small frequency splits. The introduced method is tested on a resonator gyroscope, and two stiffness axes azimuth angles are obtained with a resolution better than 0.1°. A comparison of the experimental results and theoretical model simulations confirmed the validity of our method.

A cylindrical resonator gyroscope is a kind of Coriolis gyroscope, which measures angular velocity or angle via processing of the standing wave. The symmetry of a cylindrical resonator is destroyed by different degrees of geometric nonuniformity and structural damage in the machining process. The uneven mass distribution caused by the asymmetry of the resonator can be expressed in the form of a Fourier series. The first three harmonics will reduce the anti-interference ability of the resonator to the external vibration, as well as increase the angular random walk and zero-bias drift of the gyroscope. In this paper, the frequency split of different modes caused by the first three harmonic errors and the displacement of the center of the cylindrical resonator bottom plate are obtained by simulation, and the relationship between them is explored. The experimental results on five fused silica cylindrical resonators are consistent with the simulation, confirming the linear relationship between the n = 1 frequency split and second harmonic error. A method for evaluating the first three harmonic errors of fused silica cylindrical resonators is provided.

We have presented and demonstrated a customizable trajectory of a trapped particle in the Quadruple-beam optical trap. The orbital motion of the trapped microsphere was realized by modulating the trapping power. The motion trajectories could be designed by adjusting the modulation frequency, amplitude, and phase. By using this method, we have realized the triangle, bowknot, ellipse, straight line, and hooklike trajectories. The motion frequencies and circumferences were also modulated. The customizable trajectory in the optical trap may result in more possibilities for directional movement, microfluidic mixing, driven machines, and even painting freely.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOCs) continue to wreak havoc across the globe. Higher transmissibility and immunologic resistance of VOCs bring unprecedented challenges to epidemic extinguishment. Here we describe a monoclonal antibody, 2G1, that neutralizes all current VOCs and has surprising tolerance to mutations adjacent to or within its interaction epitope. Cryo-electron microscopy structure showed that 2G1 bound to the tip of receptor binding domain (RBD) of spike protein with small contact interface but strong hydrophobic effect, which resulted in nanomolar to sub-nanomolar affinities to spike proteins. The epitope of 2G1 on RBD partially overlaps with angiotensin converting enzyme 2 (ACE2) interface, which enables 2G1 to block interaction between RBD and ACE2. The narrow binding epitope but high affinity bestow outstanding therapeutic efficacy upon 2G1 that neutralized VOCs with sub-nanomolar half maximal inhibitory concentration in vitro. In SARS-CoV-2, Beta or Delta variant-challenged transgenic mice and rhesus macaque models, 2G1 protected animals from clinical illness and eliminated viral burden, without serious impact to animal safety. Mutagenesis experiments suggest that 2G1 is potentially capable of dealing with emerging SARS-CoV-2 variants in the future. This report characterized the therapeutic antibodies specific to the tip of spike against SARS-CoV-2 variants and highlights the potential clinical applications as well as for developing vaccine and cocktail therapy., (© 2022. The Author(s).)

Photothermal therapy (PTT) is a promising strategy for the treatment of advanced malignant neoplasm. However, the anti-tumor efficacy by PTT alone is insufficient to control tumor growth and metastasis. Here, we report a multifunctional nanotherapeutic system exerting a combined PTT and immunotherapy to synergistically enhance the therapeutic effect on melanoma. In particular, we selected the semiconductor nanomaterial copper sulfide (CuS), which served not only as a near-infrared (NIR) light-triggered photothermal converter for tumor hyperthermia but as a basic carrier to modify Cas9 ribonucleoprotein targeting PTPN2 on its surface. Efficient PTPN2 depletion was observed after the treatment of CuS-RNP@PEI nanoparticles, which caused the accumulation of intratumoral infiltrating CD8 T lymphocytes in tumor-bearing mice and upregulated the expression levels of IFN-ᵧ and TNF-α in tumor tissue, thus sensitizing tumors to immunotherapy. In addition, the effect worked synergistically with tumor ablation and immunogenic cell death (ICD) induced by PTT to amplify anti-tumor efficacy. Taken together, this exogenously controlled method provides a simple and effective treatment option for advanced malignant neoplasm., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Near-infrared (NIR)-light-triggered photothermal therapy (PTT) is usually associated with undesirable damage to healthy organs nearby due to the high temperatures (>50 °C) available for tumor ablation. Low-temperature PTT would therefore have tremendous value for clinical application. Here, we construct a hypoxia-responsive gold nanorods (AuNRs)-based nanocomposite of CRISPR-Cas9 for mild-photothermal therapy via tumor-targeted gene editing. AuNRs are modified with azobenzene-4,4'-dicarboxylic acid (p-AZO) to achieve on-demand release of CRISPR-Cas9 using hypoxia-responsive azo bonds. In the hypoxic tumor microenvironment, the azo groups of the hypoxia-activated CRISPR-Cas9 nanosystem based on gold nanorods (APACPs) are selectively reduced by the overexpression of reductases, leading to the release of Cas9 and subsequent gene editing. Owing to the knockout of HSP90α for reducing the thermal resistance of cancer cells, highly effective tumor ablation both in vitro and in vivo was achieved with APACPs under mild PTT., (© 2021 Wiley-VCH GmbH.)

The feedback control to optical tweezers is an obvious approach to improve the optical confinement. However, the electronic-based feedback controlling system in optical tweezers usually consists of complex software and hardware, and its performance is limited by the inevitable noise and time-delay from detecting and controlling devices. Here, we present and demonstrate the dual-beam intracavity optical tweezers enabling all-optical independent radial and axial self-feedback control of the trapped particle's radial and axial motions. We have achieved the highest optical confinement per unit intensity to date, to the best of our knowledge. Moreover, both the axial and radial confinements are adjustable in real-time, through tuning the foci offset of the clockwise and counter-clockwise beams. As a result, we realized three-dimensional self-feedback control of the trapped particle's motions with an equivalent level in the experiment. The dual-beam intracavity optical tweezers will significantly expand the range of optical manipulation in further studies of biology, physics and precise measurement, especially for the sample that is extremely sensitive to heat.

For the axisymmetric shell resonator gyroscopes, the quality factor (Q factor) of the resonator is one of the core parameters limiting their performances. Surface loss is one of the dominating losses, which is related to the subsurface damage (SSD) that is influenced by the grinding parameters. This paper experimentally studies the surface roughness and Q factor variation of six resonators ground by three different grinding speeds. The results suggest that the removal of the SSD cannot improve the Q factor continuously, and the variation of surface roughness is not the dominant reason to affect the Q factor. The measurement results indicate that an appropriate increase in the grinding speed can significantly improve the surface quality and Q factor. This study also demonstrates that a 20 million Q factor for fused silica cylindrical resonators is achievable using appropriate manufacturing processes combined with post-processing etching, which offers possibilities for developing high-precision and low-cost cylindrical resonator gyroscopes.

The cylindrical resonator gyroscope (CRG) is a type of Coriolis vibratory gyroscope which measures the angular velocity or angle through the precession of the elastic wave of the cylindrical resonator. The cylindrical fused silica resonator is an essential component of the CRG, the symmetry of which determines the bias drift and vibration stability of the gyroscope. The manufacturing errors breaking the symmetry of the resonator are usually described by Fourier series, and most studies are only focusing on analyzing and reducing the fourth harmonic error, the main error source of bias drift. The second harmonic error also is one of the obstacles for CRG towards high precision. Therefore, this paper provides a chemical method to evaluate and balance the second harmonic error of cylindrical fused silica resonators. The relation between the frequency split of the n = 1 mode and the second harmonic error of the resonator is obtained. Simulations are performed to analyze the effects of the first three harmonic errors on the frequency splits. The relation between the location of the low-frequency axis of n = 1 mode and the heavy axis of the second harmonic error is also analyzed by simulation. Chemical balancing experiments on two fused silica resonators demonstrate the feasibility of this balancing procedure, and show good consistency with theoretical and simulation analysis. The second harmonic error of the two resonators is reduced by 86.6% and 79.8%, respectively.

Single beam intracavity optical tweezers characterizes a novel optical trapping scheme where the laser operation is nonlinearly coupled to the motion of the trapped particle. Here, we first present and establish a physical model from a completely new perspective to describe this coupling mechanism, using transfer matrices to calculate the loss of the free-space optical path and then extracting the scattering loss that caused by the 3D motions of the particle. Based on this model, we discuss the equilibrium position in the single beam intracavity optical tweezers. The influences of the numerical aperture, pumping power, particle radius and refractive index on the optical confinement efficiency are fully investigated, compared with standard optical tweezers. Our work is highly relevant for guiding the experiments on the single beam intracavity optical tweezers to achieve higher optical confinement efficiency.

The formation of an immunosuppressive microenvironment and up-regulation of PD-L1 protein are the main causes of tumor immune escape. Previous reports suggest that Angiotensin II (Ang II) can modulate the immune status of tumor microenvironment in non-small cell lung cancer (NSCLC), but the underlying mechanism remains not fully understood. Here we demonstrated that AngII treatment causes the reduction of intratumoral infiltrating CD4 T lymphocytes in tumor-bearing mice, increases the accumulation of immunosuppressive granulocytes and TAMs in tumor tissue, and upregulates the expression levels of immunosuppressive marker genes. In addition, AngII/AGTR1 axis triggers cell PD-L1 expression through a mechanism involving increases in PD-L1 mRNA stability by human antigen R (HuR), an AU-rich element (ARE)-binding protein. Collectively, AngII/AGTR1 signaling promotes the tumor immunosuppressive microenvironment by upregulating PD-L1 in NSCLC, the mechanism of which is largely accounted by HuR-mediated PD-L1 mRNA stabilization., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The fused silica cylindrical resonator is a type of axisymmetric resonator that can be used for Coriolis vibratory gyroscopes. Although the resonant frequency, frequency mismatch, and Q factor are natural properties of the resonator, they can change with temperature. Therefore, the temperature drift severely limits the detection accuracy and bias stability of the gyroscope. In this paper, the influence of temperature variation on the vibrational characteristics of fused silica cylindrical resonators was investigated. Experiments were performed on a fused silica cylindrical resonator coated with Cr/Au films. It was shown that at the temperature range from 253.15 K to 353.15 K, the resonant frequency linearly increased with temperature, the frequency mismatch remained unchanged, and the Q factor gradually increased till about 333.15 K, when it began to decrease. Meanwhile, the change of thermoelastic damping with temperature may dominate the variation of Q factor at the temperature range from 253.15 K to 353.15 K. This phenomenon was theoretically analyzed and the variation trends of results were consistent with the theoretical analysis. This study indicates that, for the fused silica cylindrical resonator, to discover the influence of temperature variation on the resonant frequency, frequency mismatch, and Q factor, there are certain rules to follow and repeat. The relationship between temperature and frequency can be established, which provides the feasibility of using self-calibration based on temperature characteristics of the resonator for temperature drift compensations. Additionally, there is an optimum temperature that may improve the performance of the Coriolis vibratory gyroscope with the fused silica cylindrical resonator.

The Coriolis Vibratory Gyroscopes are a type of sensors that measure angular velocities through the Coriolis effect. The resonator is the critical component of the CVGs, the vibrational characteristics of which, including the resonant frequency, frequency mismatch, Q factor, and Q factor asymmetry, have a great influence on the performance of CVG. The frequency mismatch and Q factor of the resonator, in particular, directly determine the precision and drift characteristics of the gyroscope. Although the frequency mismatch and Q factor are natural properties of the resonator, they can change with external conditions, such as temperature, pressure, and external forces. In this paper, the influence of electrostatic forces on the vibrational characteristics of the fused silica cylindrical resonator is investigated. Experiments were performed on a fused silica cylindrical resonator coated with Cr/Au films. It was shown that the resonant frequency, frequency mismatch, and the decay time slightly decreased with electrostatic forces, while the decay time split increased. Lower capacitive gaps and larger applied voltages resulted in lower frequency mismatch and lower decay time. This phenomenon was theoretically analyzed, and the variation trends of results were consistent with the theoretical analysis. This study indicates that, for fused silica cylindrical resonator with electrostatic transduction, the electrostatic influence on the Q factor and frequency, although small, should be considered when designing the capacitive gap and choosing bias voltages.

Background and Purpose: In non-small-cell lung carcinoma (NSCLC) patients, the L858R/T790M mutation of the epithelial growth factor receptor (EGFR) is a major cause of acquired resistance to EGFR-TKIs treatment that limits their therapeutic efficacy. Identification of drugs that can preferentially kill the NSCLC harbouring L858R/T790M mutation is therefore critical. Here, we have evaluated the effects of ursolic acid, an active component isolated from herbal sources, on erlotinib-resistant H1975 cells that harbour the L858R/T790M mutation., Experimental Approach: Gene expression omnibus (GEO) profiles analyses was applied to detect differentially expressed genes in NSCLC cells harbouring EGFR mutation. AnnexinV-FITC/PI, TUNEL staining, MTT, wound healing, RT-PCR, qRT-PCR, western blots, immunostaining, dual-luciferase reporters and ChIP-PCR were utilized to investigate the effects of ursolic acid in vitro and in vivo., Key Results: The cancer/testis antigen family 45 member A2 (CT45A2) was highly expressed in H1975 cells. Ectopic expression of CT45A2 in H1975 cells increased cell proliferation and motility in vitro. Silencing the CT45A2 expression strongly attenuated H1975 cells motility and growth. The anti-cancer effect of ursolic acid was critically dependent on CT45A2 expression in H1975 cells. Ursolic acid suppressed CT45A2 gene transcription mediated by transcriptional factor TCF4 and β-catenin signalling., Conclusions and Implications: CT45A2 is a novel oncogene for NSCLC with an EGFR T790 mutation. Ursolic acid induced apoptosis and inhibited proliferation of H1975 cells by negatively regulating the β-catenin/TCF4/CT45A2 signalling pathway. Therefore, ursolic acid may be a potential candidate treatment for NSCLC harbouring the EGFR-L858R/T790M mutation., (© 2019 The British Pharmacological Society.)

Background: Glioblastoma survival remains unchanged despite continuing therapeutic innovation. Herein, we aim to (i) develop chimeric antigen receptor (CAR) T cells with a specificity to a unique antigen, carbonic anhydrase IX (CAIX), which is expressed in the hypoxic microenvironment characteristic of glioblastoma, and (ii) demonstrate its efficacy with limited off-target effects., Methods: First we demonstrated expression of CAIX in patient-derived glioblastoma samples and available databases. CAR T cells were generated against CAIX and efficacy was assessed in 4 glioblastoma cell lines and 2 glioblastoma stem cell lines. Cytotoxicity of anti-CAIX CAR T cells was assessed via interferon gamma, tumor necrosis factor alpha, and interleukin-2 levels when co-cultured with tumor cells. Finally, we assessed efficacy of direct intratumoral injection of the anti-CAIX CAR T cells on an in vivo xenograft mouse model using the U251 luciferase cell line. Tumor infiltrating lymphocyte analyses were performed., Results: We confirm that CAIX is highly expressed in glioblastoma from patients. We demonstrate that CAIX is a suitable target for CAR T-cell therapy using anti-CAIX CAR T cells against glioblastoma in vitro and in vivo. In our mouse model, a 20% cure rate was observed without detectable systemic effects., Conclusions: By establishing the specificity of CAIX under hypoxic conditions in glioblastoma and highlighting its efficacy as a target for CAR T-cell therapy, our data suggest that anti-CAIX CAR T may be a promising strategy to treat glioblastoma. Direct intratumoral injection increases anti-CAIX CAR T-cell potency while limiting its off-target effects., (Published by Oxford University Press on behalf of the Society for Neuro-Oncology 2019.)

The cylindrical resonator gyroscope (CRG) is a kind of solid-state gyroscope with a wide application market. The cylindrical resonator is the key component of CRG, whose quality factor and symmetry will directly affect the performance of the gyroscope. Due to the material properties and fabrication limitations, the actual resonator always has some defects. Therefore, frequency trimming, i.e., altering the local mass or stiffness distribution by certain methods, is needed to improve the overall symmetry of the resonator. In this paper, we made further derivation based on the chemical trimming theory proposed by Basarab et al. We built up the relation between the frequency split and the balanced mass to determine the mass to be removed. Chemical trimming experiments were conducted on three cylindrical fused silica resonators. The frequency splits of the three resonators were around 0.05 Hz after chemical trimming. The relation between frequency split and balanced mass established from experimental data was consistent with the theoretical calculation. Therefore, frequency split can be reduced to lower than 0.05 Hz under rigorous theoretical calculation and optimized chemical trimming parameters.

Fused silica cylindrical resonant gyroscope (CRG) is a novel high-precision solid-wave gyroscope, whose performance is primarily determined by the cylindrical resonator's frequency split and quality factor (Q factor). The laser Doppler vibrometer (LDV) is extensively used to measure the dynamic behavior of fused silica cylindrical resonators. An electrical method was proposed to characterize the dynamic behavior of the cylindrical resonator to enhance the measurement efficiency and decrease the equipment cost. With the data acquisition system and the designed signal analysis program based on LabVIEW software, the dynamic behavior of the fused silica cylindrical resonator can be analyzed automatically and quickly. We compared all the electrical measurement results with the optical detection by LDV, demonstrating that the fast Fourier transform (FFT) result of the resonant frequency measured by the electrical method was 0.12 Hz higher than that with the optical method. Thus, the frequency split measured by the electrical and optical methods was the same in 0.18 Hz, and the measurement of the Q factor was basically the same in 730,000. We conducted all measurements under the same operation condition, and the optical method was used as a reference, demonstrating that the electrical method could characterize the dynamic behavior of the fused silica cylindrical resonator and enhance the measurement efficiency.

The luminescence properties of Ba 13 . 35 Al 30 . 7 Si 5 . 3 O 70 :Eu 2+ and Ba 13 . 35 Al 30 . 7 Si 5 . 3 O 70 :Eu 2+ ,Tm 3+ phosphors are presented. After being excited by a light source, Ba 13 . 35 Al 30 . 7 Si 5 . 3 O 70 :Eu 2+ ,Tm 3+ phosphors emit intense yellow long persistent luminescence covering the region from 450 to 700 nm, which can last about 8 h. Thermoluminescence curves were demonstrated to analyze the trapping nature of persistent luminescence. Tm 3+ is added to improve the long persistent luminescence properties of phosphors. The mechanism of persistent luminescence has been studied., Competing Interests: The authors declare no competing financial interest.

We propose an all-fiber interferometer based on laser Doppler velocimetry in a dual-beam fiber-optic trap to measure the displacement and velocity of a trapped particle. ABCD matrices are used to compute the contrast ratio of the interference. The influence of the reflectivity of the fiber end face is discussed. We have designed an optimized reflectivity based on the parameters of our setup. The antireflective coatings on the fiber end face are employed to achieve the given reflectivity. The displacement and velocity of the trapped microparticle are successfully measured by the period and frequency of the interference signal, respectively. The sensitivity of the displacement detection is 368 nm. By describing the miniaturization of the detection system, this paper provides a simple and practical scheme to achieve the integration of the entire optical trapping setup.

The hemispherical resonator gyroscope (HRG) has attracted the interest of the world inertial navigation community because of its exceptional performance, ultra-high reliability and its potential to be miniaturized. These devices achieve their best performance when the differences in the frequencies of the two degenerate working modes are eliminated. Mechanical treatment, laser ablation, ion-beams etching, etc., have all been applied for the frequency tuning of resonators, however, they either require costly equipment and procedures, or alter the quality factors of the resonators significantly. In this paper, we experimentally investigated for the first time the use of a chemical etching procedure to decrease the frequency splits of hemispherical resonators. We provide a theoretical analysis of the chemical etching procedure, as well as the relation between frequency splits and mass errors. Then we demonstrate that the frequency split could be decreased to below 0.05 Hz by the proposed chemical etching procedure. Results also showed that the chemical etching method caused no damage to the quality factors. Compared with other tuning methods, the chemical etching method is convenient to implement, requiring less time and labor input. It can be regarded as an effective trimming method for obtaining medium accuracy hemispherical resonator gyroscopes.

Musashi-1 (Msi1) is an evolutionarily conserved RNA-binding protein that has been reported to be the key regulator in malignancies and with involvement in cancer stemness. In the present study, a novel Msi1 transcript variant generated by alternative splicing was identified and termed Msi1 variant 2. This variant was observed to be ubiquitously expressed in cancerous and non-cancerous cells compared with its wild-type variant, which is preferentially expressed in cancer cells. Notably, the expression levels of Msi1 variant 2 were inversely associated with the protein expression levels of Msi1 in various cancer cells. This naturally truncated variant contains 899 nucleotides and a skipping event of exons 3 and 4, which leads to the emergence of a premature TGA stop codon in exon 5. The present results also demonstrated that hypoxia increased the resistance of H460 cells to cisplatin by suppressing the exon 3 and 4 skipping event of Msi1. In summary, the present study identified a novel splice variant of Msi1 lacking two complete RNA recognition motifs, and revealed the role of exon 3 and 4 skipping of Msi1 pre-mRNA in regulating cisplatin resistance under hypoxia. These observations indicate that targeting Msi1 alternative splicing could represent a valuable strategy to repress Msi1 signaling in tumors overexpressing this RNA-binding protein.

The cylindrical resonator gyroscope (CRG) is a typical Coriolis vibratory gyroscope whose performance is determined by the Q factor and frequency mismatch of the cylindrical resonator. Enhancing the Q factor is crucial for improving the rate sensitivity and noise performance of the CRG. In this paper, for the first time, a monolithic cylindrical fused silica resonator with a Q factor approaching 8 × 10⁵ (ring-down time over 1 min) is reported. The resonator is made of fused silica with low internal friction and high isotropy, with a diameter of 25 mm and a center frequency of 3974.35 Hz. The structure of the resonator is first briefly introduced, and then the experimental non-contact characterization method is presented. In addition, the post-fabrication experimental procedure of Q factor improvement, including chemical and thermal treatment, is demonstrated. The Q factor improvement by both treatments is compared and the primary loss mechanism is analyzed. To the best of our knowledge, the work presented in this paper represents the highest reported Q factor for a cylindrical resonator. The proposed monolithic cylindrical fused silica resonator may enable high performance inertial sensing with standard manufacturing process and simple post-fabrication treatment.

The orbital rotation is an important type of motion of trapped particles apart from translation and spin rotation. It could be realized by introducing a transverse offset to the dual-beam fiber-optic trap. The characteristics (e.g. rotation perimeter and frequency) of the orbital rotation have been analyzed in this article. We demonstrate the influences of offset distance, beam waist separation distance, light power, and radius of the microsphere by both experimental and numerical work. The experiment results, i.e. orbital rotation perimeter and frequency as functions of these parameters, are consistent with the theoretical model in the present work. The orbital rotation amplitude and frequency could be exactly controlled by varying these parameters. This controllable orbital rotation can be easily applied to the area where microfluidic mixing is required.

The presence of a magnetic field gradient in a sample cell containing spin-polarized (129)Xe atoms will cause an increased relaxation rate. We measured the transverse spin relaxation time of (129)Xe verse the applied magnetic field gradient and the cell temperature. We then compared the different transverse spin relaxation behavior of dual isotopes of xenon ((129)Xe and (131)Xe) due to magnetic field gradient in the same cell. The experiment results show the residual magnetic field gradient can be measured and compensated by applying a negative magnetic gradient in the sample cell. The transverse spin relaxation time of (129)Xe could be increased 2-7 times longer when applying an appropriate magnetic field gradient. The experiment results can also be used to determine the diffusion constant of (129)Xe in H2 and N2 to be 0.4 ± 0.26 cm(2)/sec and 0.12 ± 0.02 cm(2)/sec. The results are close with theoretical calculation.

A comprehensive dynamics analysis of microsphere has been presented in a dual-beam fiber-optic trap with transverse offset. As the offset distance between two counterpropagating beams increases, the motion type of the microsphere starts with capture, then spiral motion, then orbital rotation, and ends with escape. We analyze the transformation process and mechanism of the four motion types based on ray optics approximation. Dynamic simulations show that the existence of critical offset distances at which different motion types transform. The result is an important step toward explaining physical phenomena in a dual-beam fiber-optic trap with transverse offset, and is generally applicable to achieving controllable motions of microspheres in integrated systems, such as microfluidic systems and lab-on-a-chip systems.

Neurological disease comprises a series of disorders featuring brain dysfunction and neuronal cell death. Among the factors contributing to neuronal death, excitotoxicity induced by excitatory amino acids, such as glutamate, plays a critical role. However, the mechanisms about how the excitatory amino acids induce neuronal death remain elucidated. In this study, we investigated the role of HIF-1α (hypoxia inducible factor-1α) and RTP801 in cell apoptosis induced by quinolinic acid (QUIN), a glutamatergic agonist, in PC12 cells. We found that QUIN at 5 μM increased the expression of HIF-1α significantly with a peak at 24 h. After the treatment with QUIN (5-20 μM) for 24 h, the cells exhibited decreased viability and cell apoptosis with a concomitant increased expression of apoptosis related proteins. QUIN treatment also induced the generation of intracellular reactive oxygen species and RTP801 up-regulation in a HIF-1α-dependent manner that were inhibited by 2-methoxyestradiol, a HIF-1α inhibitor. Importantly, HIF-1 or RTP801 invalidation by siRNA rescued the cell apoptosis induced by QUIN or cobalt chloride, a chemical inducer of HIF-1. Taken together, these findings support the concept that neurotoxicity induced by QUIN is associated with HIF-1-dependent RTP801 activation and provide insight into the potential of RTP801 inhibitor in treatment of neurological disorders.

Background: With increasing use of high-resolution imaging of brain, unruptured aneurysms are more and more frequently detected. With the advances in treatment techniques, an increasing number of aneurysms are now occluded using endovascular coiling instead of conventional surgical clipping. However, the better modality for unruptured intracranial aneurysm has been poorly understood., Objective: The objective of this meta-analysis was to compare the outcomes between endovascular coiling and surgical clipping among patients with unruptured intracranial aneurysms., Methods: PubMed, Embase, Web of Science, CENTRAL, and SIGLE were electronically searched from January 1, 1990 to March 13, 2012 with no language restriction for randomized or nonrandomized clinical controlled trials. Article screening and data extraction were conducted in duplicate. Results were statistically pooled through Review Manager 5 and StatsDirect 2.7.9., Results: Seven studies met our inclusion criteria. The pooled risk ratios (coiling vs. clipping) were 0.59 (95% CI = 0.23-1.54) for death; 0.37 (95% CI = 0.10-1.41) for bleeding; 0.78 (95% CI = 0.38-1.58) for cerebral ischemia; 0.87 (95% CI = 0.70-1.08) for occlusion of aneurysm; 0.53 (95% CI = 0.18-1.52) for independence in daily activities. The pooled rates of death, bleeding, ischemia, occlusion of aneurysm, and mRS no less than 3 were 1% (95% CI = 0-2%), 2% (95% CI = 0-5%), 8% (95% CI = 4-13%), 82% (95% CI = 64-95%), and 5% (95% CI = 1-10%) for endovascular coiling, respectively, and 1% (95% CI = 0-2%), 6% (95% CI = 3-10%), 9% (95% CI = 5-15%), 95% (95% CI = 90-98%), and 8% (95% CI = 3-14%) for surgical clipping, respectively. We failed to evaluate quality of life and cognitive outcome due to insufficient data. Both meta-regression and sensitivity analysis showed consistent results. Furthermore, Begg's test and Egger's test failed to detect publication bias., Conclusion: We suggest that endovascular coiling and surgical clipping bear similar risk ratios of death, bleeding, cerebral ischemia, occlusion of aneurysm, and independence in daily activities and encourage further studies on quality of life and cognitive outcome. However, albeit the results in this meta-analysis are robust, due to great clinical heterogeneity and low quality of studies, the results in this meta-analysis should be interpreted with caution.

We propose and analyze a superluminal ring laser gyroscope (RLG) using multilayer optical coatings with huge group delay (GD). This GD assisted superluminal RLG can measure the absolute rotation with a giant sensitivity-enhancement factor of ~10(3); while, the broadband FWHM of the enhancement factor can reach 20 MHz. This superluminal RLG is based on a traditional RLG with minimal re-engineering, and beneficial for miniaturization according to theoretical calculation. The idea of using GD coatings as a fast-light medium will shed lights on the design and application of fast-light sensors.

Objective: To explore the clinical classification and selection of surgical approaches for cervical spinal dumbbell tumors., Methods: The clinical data of 87 patients with cervical spinal dumbbell tumors undergoing surgical operations from January 2005 to December 2012 at our hospital were analyzed retrospectively. According to the size of inner and outer parts of tumors and the presence or absence of spinal bone damage, the cervical spinal dumbbell tumors were divided into 4 types of intraspinal predominant (I, n = 48), extraspinal predominant (II, n = 1), intrapinal and extraspinal without damage of spinal bone (III, n = 15) and intrapinal and extraspinal type with damage of spinal bone (IV, n = 7). Different surgical approaches were selected on the basis of tumor classification: posterior median-hemilamina approaches for type I tumors, lateral-muscle gap approaches for type II tumors, ateral-muscle gap-hemilamina or lateral-muscle gap-posterior median-hemilamina approaches for type III tumors, posterior far lateral-muscle gap-hemilamina or posterior median-muscle gap-hemilamina approaches plus posterior occipital cervical or cervical spinal bone graft fusion and internal fixation for type IV tumors., Results: Among them, 83 cases underwent total resection and another 4 subtotal resection in one-stage operation. The postoperative follow-up period had a range of 9 months to 6 years (mean, 3.2 years). There was no recurrence of tumors for total resection and 1 case of tumor recurrence for subtotal resection. During the follow-up period, the clinical manifestations of 85 patients improved while another 2 deteriorated. And there was no occurrence of spinal deformity., Conclusion: Clinical classification of cervical spinal dumbbell tumor plays an important guiding role in the selection of surgical approaches. Adopting appropriate surgical approaches based on tumor type can not only improve the rate of total resection of tumor but also reduce the incidence of postoperative spinal deformity.

The inhomogeneity of high-reflectivity mirror coatings is a potential error source in the application of the cavity ringdown technique. Here, the ringdown times for different transverse modes were recorded. Together with the observed spatial distribution of these modes the ringdown times can be used to approximately locate the position of coating defects. A simple model based on a weighted sum of Hermite-Gaussian mode functions is used to explain the experimental results.

A miniaturized HeNe laser with intensity and frequency simultaneously stabilized is described. The laser uses a monoblock glass ceramics as its tube to construct an improved steady structure. The closed loop cavity length control system stabilizes its frequency and the discharge current regulating system stabilizes its intensity. The electronic system integrating power supply and stabilization system is designed within two small circuit boards. The laser tube and circuit boards are assembled into a small package with dimensions of 180 mm×100 mm×150 mm. The laser outputs s-polarized light at wavelength of 632.99 nm with power of 0.44 mW. Test results show that its frequency stability can reach 8.4×10(-11) (1s Allan variance over 3 h) and frequency reproducibility at 1.3×10(-8). The laser's intensity stability is 0.011% over 9 h.

Leptin-deficient ob/ob mice are overweight, develop insulin resistance, and serve as a model for type 2 diabetes (T2D). Studies suggest that inflammatory pathways are linked to the development of insulin resistance and T2D both in animals and humans. We asked whether the induction of regulatory T cells (Tregs) could alleviate the pathological and metabolic abnormalities in ob/ob mice. We induced TGF-beta-dependent CD4(+) latency-associated peptide (LAP)-positive Tregs by oral administration of anti-CD3 antibody plus beta-glucosylceramide. We found a decrease in pancreatic islet cell hyperplasia, fat accumulation in the liver, and inflammation in adipose tissue, accompanied by lower blood glucose and liver enzymes. In addition, treated animals had decreased CD11b(+)F4/80(+) macrophages and TNF-alpha in adipose tissue. Adoptive transfer of orally induced CD4(+)LAP(+) Tregs ameliorated metabolic and cytokine abnormalities. Our results demonstrate the importance of inflammation in T2D and identify a unique immunological approach for treatment of T2D by the induction of Tregs.

Somatic hypermutation normally occurs as a consequence of the expression of activation-induced cytidine deaminase (AID) by Ag-activated, mature B cells during T cell-dependent germinal center responses. Nonetheless, despite their inability to express CD154 and initiate GC responses, patients with type 1 hyper-IgM syndrome (HIGM1) support populations of IgM(+)IgD(+)CD27(+) B cells that express mutated Ig genes. The origin of these mutated B cells is unknown; the IgM(+)IgD(+)CD27(+) cells do not express AID and appear to acquire mutations independent of stringent selection by Ag. Here, we demonstrate that immature/transitional 1 B cells from the bone marrow of CD154-deficient mice express AID and acquire Ig mutations that lack the hallmarks of antigenic selection via BCR signaling. Comparable levels of AID expression was found in developmentally immature B cells recovered from murine fetal liver and from human immature/transitional 1 B cells recovered from umbilical cord blood. AID expression in human fetal liver was also robust, approaching that of human tonsil tissue and the human germinal center B cell line, Ramos. These observations led us to conclude that AID expression in developing human B cells is the origin of the mutated IgM(+)IgD(+)CD27(+) B cells present in HIGM1 patients, and we propose that both mice and humans share a latent, AID-dependent pathway for the preimmune diversification of B lymphocytes that is more prominent in chicken, sheep, and rabbits.

Transforming growth factor beta (TGF-beta) plays a role both in the induction of Treg and in the differentiation of the IL-17-secreting T cells (Th17) which drive inflammation in experimental autoimmune encephalomyelitis (EAE). We investigated the role that thrombospondin-1 (TSP-1) dependent activation of TGF-beta played in the generation of an encephalitic Th17 response in EAE. Upon immunization with myelin oligodendrocyte glycoprotein peptide (MOG(35-55)), TSP-1 deficient (TSP-1(null)) mice and MOG(35-55) TCR transgenic mice that lack of TSP-1 (2D2 x TSP-1(null)) exhibited an attenuated form of EAE, and secreted lower levels of IL-17. Adoptive transfer of in vitro-activated 2D2 x TSP-1(null) T cells induced a milder form of EAE, independent of TSP-1 expression in the recipient mice. Furthermore, in vitro studies demonstrated that anti-CD3/anti-CD28 pre-activated CD4+ T cells transiently upregulated latent TGF-beta in a TSP-1 dependent way, and such activation of latent TGF-beta was required for the differentiation of Th17 cells. These results demonstrate that TSP-1 participates in the differentiation of Th17 cells through its ability to activate latent TGF-beta, and enhances the inflammatory response in EAE.

One of the major goals for the immunotherapy of autoimmune diseases is the induction of regulatory T cells that mediate immunologic tolerance. Parenteral administration of anti-CD3 monoclonal antibody is an approved therapy for transplantation in humans and is effective in autoimmune diabetes. We have found that oral administration of anti-CD3 monoclonal antibody is biologically active in the gut and suppresses experimental autoimmune encephalomyelitis both prior to disease induction and at the height of disease. Oral anti-CD3 antibody acts by inducing a unique type of regulatory T cell characterized by latency-associated peptide (LAP) on its cell surface that functions in vivo and in vitro via TGF-beta dependent mechanism. Orally delivered antibody would not have side effects including cytokine release syndromes, thus oral anti-CD3 antibody is clinically applicable for chronic therapy. These findings identify a novel and powerful immunologic approach that is widely applicable for the treatment of human autoimmune conditions.

CD20 mAb-mediated B cell depletion is an effective treatment for B cell malignancies and some autoimmune diseases. However, the full effects of B cell depletion on natural, primary, and secondary Ab responses and the maintenance of Ag-specific serum Ig levels are largely unknown. The relationship between memory B cells, long-lived plasma cells, and long-lived humoral immunity also remains controversial. To address the roles of B cell subsets in the longevity of humoral responses, mature B cells were depleted in mice using CD20 mAb. Peritoneal B cell depletion reduced natural and Ag-induced IgM responses. Otherwise, CD20+ B cell depletion prevented humoral immune responses and class switching and depleted existing and adoptively transferred B cell memory. Nonetheless, B cell depletion did not affect serum Ig levels, Ag-specific Ab titers, or bone marrow Ab-secreting plasma cell numbers. Coblockade of LFA-1 and VLA-4 adhesion molecules temporarily depleted long-lived plasma cells from the bone marrow. CD20+ B cell depletion plus LFA-1/VLA-4 mAb treatment significantly prolonged Ag-specific plasma cell depletion from the bone marrow, with a significant decrease in Ag-specific serum IgG. Collectively, these results support previous claims that bone marrow plasma cells are intrinsically long-lived. Furthermore, these studies now demonstrate that mature and memory B cells are not required for maintaining bone marrow plasma cell numbers, but are required for repopulation of plasma cell-deficient bone marrow. Thereby, depleting mature and memory B cells does not have a dramatic negative effect on preexisting Ab levels.

Innate immune cells may regulate adaptive immunity by balancing different lineages of T cells and providing negative costimulation. In addition, CD11b(+)Gr-1(+) myeloid-derived suppressor cells have been described in tumor, parasite infection, and severe trauma models. In this study, we observe that splenic CD11b(+) cells markedly increase after experimental autoimmune encephalomyelitis (EAE) immunization, and they suppress T cell proliferation in vitro. Although >80% of CD11b(+) cells express varying levels of Gr-1, only a small population of CD11b(+)Ly-6C(high) inflammatory monocytes (IMC) can efficiently suppress T cell proliferation and induce T cell apoptosis through the production of NO. IFN-gamma produced by activated T cells is essential to induce IMC suppressive function. EAE immunization increases the frequencies of IMC in the bone marrow, spleen, and blood, but not in the lymph nodes. At the peak of EAE, IMC represent approximately 30% of inflammatory cells in the CNS. IMC express F4/80 and CD93 but not CD31, suggesting that they are immature monocytes. Furthermore, IMC have the plasticity to up-regulate NO synthase 2 or arginase 1 expression upon different cytokine treatments. These findings indicate that CD11b(+)Ly-6C(high) IMC induced during EAE priming are powerful suppressors of activated T cells. Further understanding of suppressive monocytes in autoimmune disease models may have important clinical implications for human autoimmune diseases.

Inflammation elicits a splenic lymphopoiesis of unknown physiologic significance but one that juxtaposes developing B cells and exogenous Ag. We show that immature and transitional 1 (immature/T1) B cells constitutively express activation-induced cytidine deaminase and B lymphocyte-induced maturation protein 1 in amounts that support accelerated plasmacytic differentiation and limited class-switch recombination. In vivo, activation of immature/T1 B cells by TLR ligands or bacterial vaccine rapidly induces T1 cells to divide, proliferate, and secrete IgM, IgG, or IgA Ab; in vitro, proliferation and differentiation are substantially enhanced by B cell-activating factor. We propose that inflammation-induced extramedullary lymphopoiesis represents a specialized mechanism for innate Ab responses to microbial pathogens.

Objective: To explore better approach of resecting tumor around the anterior skull base and reconstructing the anterior skull base., Methods: In November 2004, a 49-years-old male patient with intracranial recrudescent adenoid cystic carcinoma in the anterior cranial fossa was treated using modified transcranial approach. Neurosurgeon and rhinolaryngologist cooperated to excise the tumour completely, and to reconstruct anterior skull base using the pedicle periosteum temporal musculofascial flap (15 cm x 10 cm) and the pedicle flap of aponeurosis of occipitofron tails muscle and muscular fasciae (10 cm x 6 cm)., Results: After operation, the wound healed by first intention. Complication, such as infection and cerebrospinal rhinorrhea, did not occur. The patient was discharged 10 days after operation, and was followed up for 8 months, no local recurrence were investigated and no scar formed over the face., Conclusion: The modified transcranial approach is a relatively novel exposure that enables the skilled cranial base surgeon to safely resect many malignant lesions previously and to reconstruct the defect of anterior skull base together.

A major goal of immunotherapy for autoimmune diseases and transplantation is induction of regulatory T cells that mediate immunologic tolerance. The mucosal immune system is unique, as tolerance is preferentially induced after exposure to antigen, and induction of regulatory T cells is a primary mechanism of oral tolerance. Parenteral administration of CD3-specific monoclonal antibody is an approved therapy for transplantation in humans and is effective in autoimmune diabetes. We found that orally administered CD3-specific antibody is biologically active in the gut and suppresses autoimmune encephalomyelitis both before induction of disease and at the height of disease. Orally administered CD3-specific antibody induces CD4+ CD25- LAP+ regulatory T cells that contain latency-associated peptide (LAP) on their surface and that function in vitro and in vivo through a TGF-beta-dependent mechanism. These findings identify a new immunologic approach that is widely applicable for the treatment of human autoimmune conditions.

The membrane-associated adaptor protein LAX is a linker for activation of T cells (LAT)-like molecule that is expressed in lymphoid tissues. Upon stimulation of T or B cells, it is phosphorylated and interacts with Grb2 and the p85 subunit of PI3K. LAX, however, is not capable of replacing LAT in the TCR signaling pathway. In this study we report that upon T or B cell activation, the LAX protein was up-regulated dramatically. Although disruption of the LAX gene by homologous recombination had no major impact on lymphocyte development, it caused a significant reduction in CD23 expression on mature B cells. Interestingly, naive LAX(-/-) mice had spontaneous germinal center formation. Compared with normal T and B cells, LAX(-/-) T and B cells were hyperresponsive and had enhanced calcium flux, protein tyrosine phosphorylation, MAPK and Akt activation, and cell survival upon engagement of the T or B AgRs. Our data demonstrate that LAX functions as a negative regulator in lymphocyte signaling.