Antibody Epitope of Human α‐Galactosidase A Revealed by Affinity Mass Spectrometry: A Basis for Reversing Immunoreactivity in Enzyme Replacement Therapy of Fabry Disease

α‐Galactosidase (αGal) is a lysosomal enzyme that hydrolyses the terminal α‐galactosyl moiety from glycosphingolipids. Mutations in the encoding genes for αGal lead to defective or misfolded enzyme, which results in substrate accumulation and subsequent organ dysfunction. The metabolic disease caused by a deficiency of human α‐galactosidase A is known as Fabry disease or Fabry–Anderson disease, and it belongs to a larger group known as lysosomal storage diseases. An effective treatment for Fabry disease has been developed by enzyme replacement therapy (ERT), which involves infusions of purified recombinant enzyme in order to increase enzyme levels and decrease the amounts of accumulated substrate. However, immunoreactivity and IgG antibody formation are major, therapy‐limiting, and eventually life‐threatening complications of ERT. The present study focused on the epitope determination of human α‐galactosidase A against its antibody formed. Here we report the identification of the epitope of human αGal(309–332) recognized by a human monoclonal anti‐αGal antibody, using a combination of proteolytic excision of the immobilized immune complex and surface plasmon resonance biosensing mass spectrometry. The epitope peptide, αGal(309–332), was synthesized by solid‐phase peptide synthesis. Determination of its affinity by surface plasmon resonance analysis revealed a high binding affinity for the antibody (K_D=39×10^?9 m ), which is nearly identical to that of the full‐length enzyme (K_D=16×10^?9 m ). The proteolytic excision affinity mass spectrometry method is shown here to be an efficient tool for epitope identification of an immunogenic lysosomal enzyme. Because the full‐length αGal and the antibody epitope showed similar binding affinities, this provides a basis for reversing immunogenicity upon ERT by: 1) treatment of patients with the epitope peptide to neutralize antibodies, or 2) removal of antibodies by apheresis, and thus significantly improving the response to ERT.     

F⁃P干涉仪差分锁频系统研究

为解决法布里?珀罗（Fabry?Perot, F?P）干涉仪锁频方法响应速度、抗干扰能力、长期稳定性方面存在不足的问题,提出了F?P干涉仪差分锁频方案,将存在频差的双频激光耦合入F?P谐振腔,当激光频差足够小时,两光强信号曲线存在交叉,以两光强信号的差值作为被控量,在交叉点附近构建单调过零函数,作为闭环控制系统的反馈量,实现动态差分锁频控制。基于该方案,搭建了一套F?P干涉仪微位移测量装置并开展实验验证,结果表明该装置能够实现0 ~ 300 nm范围内的微位移测量,位移测量分辨力达到23 pm,验证了F?P干涉仪差分锁频方案的有效性,为推动微位移测量领域的发展提供了重要借鉴。     

PBG结构缺陷的谐振特性研究

本文研究了矩形波导中利用介质层PBG结构形成的Fabry-Perot谐振器的特性,并详细分析了PBG结构的纵向长度、谐振区长度以及介质层介电常数对其谐振特性的影响。本文以制作此类谐振器具有一定的参考价值。     

EBBA液晶的光学双稳态研究

利用光自聚焦和Ｆ－Ｐ腔两种手段,对ＥＢＢＡ液晶进行了光学双稳态研究,实验是在６０μｍ液晶薄膜中采用连续Ａｔ＾＋激光器进行了,确定出温度五光学双稳态和多级光学双稳态回线的关系,讨论了ＥＢＢＡ液晶在固态相和液晶相及其相变过程中光学双稳态的机制。     

FBG-FP的应变与温度解耦方法研究

光纤光栅(Fiber Bragg Grating, FBG)的温度与应变交叉敏感问题在实际工程应用中至关重要。本文提出了一种采用级联FBG的法布里-珀罗(FBG-Fabry-Perot, FBG-FP)传感器进行温度与应变同时测量的方法。级联FBG阵列由氩离子紫外激光器基于相位掩模板方法制作,其形成的FP干涉峰和光栅反射谱包络可以实现温度与应变的解耦。在不同的温度条件下,由FBG-FP反射谱包络10 dB带宽所对应中心波长值可得FBG-FP的温度灵敏度系数为9.5 pm/℃。分别在无应力、有应力且恒温条件下,通过解读FP干涉峰的波长变化得到该级联FBG-FP的温度和应变灵敏度系数分别为9.1 pm/℃和1.03 pm/με。实测的温度与应变值可由干涉峰波长、反射谱包络与温度、应变的函数关系求得。结果表明该FBG-FP可以实现温度与应变的同时测量。     

Light trapping schemes in organic solar cells: A comparison between optical Tamm states and Fabry–Pérot cavity modes

Recently optical Tamm states at metal/photonic crystals interface have been applied in thin-film organic solar cells (OSCs) as a new light trapping scheme for photon absorption enhancement. In this work, we theoretically investigate this scheme thoroughly to optimize the absorption performance for such optical Tamm states based OSCs (OTS–OSCs). We find that the overall absorptivity of the OTS–OSCs can be improved by using photonic crystals bilayers with a higher refractive index contrast, which is a result of the more strongly enhanced field intensity in the active layers. The conventional Fabry–Pérot cavity modes based OSCs (FP–OSCs) are also studied for comparison, whose absorption performance is found to be strongly dependent on the refractive index of the additional dielectric layer. These two schemes based OSCs exhibit comparable absorption performance in aspects of absorption enhancement, field distributions, and angle effect in the planar case. However, the proposed OTS–OSCs exhibit ～10% higher overall absorptivity than that for the FP–OSCs in the corrugated case, if both OSCs exhibit the same overall absorptivity in the planar case. The reduced absorption in the corrugated FP–OSCs is a result of the strong scatterings induced losses in the metal, which can be avoided by the photonic crystals bilayers in the OTS–OSCs. Therefore, the proposed Tamm states based scheme shows a higher value in corrugated OSCs.     

Simulation experiments to generate broadband chaos using dual-wavelength optically injected Fabry–Perot laser

Abstract

Broadband chaos can be generated by beating two wavelengths in a hybrid arrangement of Fabry–Perot (FP) Laser and Fiber ring cavity by injecting dual wavelengths. The bandwidth of generated chaos can be controlled by detuning different modes of FP Laser for beating. The bandwidth of generated chaos increased to many folds depending upon the injected strength and wavelength spacing matched to FP laser modes. The bandwidth enhancement in different simulation experiments conducted is optimized by varying different parameters of FP laser and cavity. The waveforms are analyzed and Lyapunov exponents are calculated in order to validate the existence of high bandwidth non-pulsating chaos.     

共焦法布里-珀罗干涉仪腔长控制系统的设计

为了提高共焦法布里一珀罗干涉仪在激光超声检测中的抗干扰能力,提出了一种利用单片机控制干涉仪腔长的原理和方法。该控制系统能根据特定情况自动确定干涉仪工作点所对应的电压值,并将该值与实时检测的电压值进行比较后,自动改变压电陶瓷管的驱动电压以调整腔长,从而达到稳定工作点的目的。实际运行结果表明,系统运行可靠并成功实现了干涉仪工作点的实时控制。