光学断层分子成像定量分析及其应用
发布时间：2018-08-23 21:44
【摘要】：近十年来，光学断层分子成像（Optical Molecular Tomography, OMT）因其在预临床的重大疾病研究应用中所表现出的良好性能，受到了学者们的广泛关注。光学断层分子成像由于具有灵敏度高、成本相对低廉、可能实现绝对定量等诸多优点，因而在预临床和临床的恶性肿瘤、心血管疾病、神经系统病变等重大疾病研究中得到了广泛的应用。作为光学断层分子成像的典型代表，生物发光断层成像及超高分辨率micro-CT混合成像系统以其高灵敏性、高特异性及高分辨的解剖结构等优点，在生物医学研究中具有广阔的应用前景。本文对光学断层分子成像的绝对定量分析方法进行了深入研究，并就生物发光断层分子成像和超高分辨率micro-CT混合成像系统对胃癌和干细胞移植治疗缺血性疾病的生物医学应用进行了系统的成像研究，本论文的主要研究内容包括： 1.构建了生物发光断层分子成像和超高分辨率micro-CT混合成像系统，并对生物发光断层分子成像系统进行了定量校准。针对预临床小动物研究的需要，，构建了生物发光断层分子成像系统，并对成像系统CCD相机进行了像元响应的非均匀性校准和绝对强度的定量校准。针对光学断层分子成像空间位置的差异构建了视场函数，对进入光学成像系统的光通量进行了定量分析。构建了超高分辨率micro-CT成像系统，为本论文的下肢缺血模型的血管新生定量研究奠定了基础。 2.对生物发光断层分子成像定量重建方法进行了研究。基于有限元网格剖分方法，提出了总能量定量重建的策略。通过已知光源移植到小动物体内，验证了总能量重建的可行性。建立了基于报告基因系统的光学探针所反映的生物学参数与成像系统中总能量重建的物理参数之间的内在联系，实现了生物发光断层分子成像系统对肿瘤细胞和干细胞的细胞数量的定量分析。通过PC-3M-luc-C6前列腺癌和A549-luc-C8非小细胞肺癌细胞系以及脂肪来源的间充质干细胞的在体定量研究，证实了细胞水平定量分析的可行性和适用性。 3.研究了光学断层分子成像在光学探针峰值波长偏移及解剖结构模型偏差等情况下引入的重建误差及其贡献率的大小。以生物发光断层成像为例分析了光学断层分子成像的重建误差的主要来源。（1）在假定光学参数准确的前提下，研究了动物模型解剖结构偏差带来的光学重建在定位和定量上的偏差。（2）在假定解剖结构准确的情况下，研究了光学探针峰值波长偏移对重建误差在定位和定量方面的影响。通过对解剖结构偏差以及峰值波长偏移的实验数据的系统测试、重建及数据分析，表明二者均会对重建的定位和定量带来较大的影响；其中，当光学探针峰值波长在640nm以下时，解剖结构的偏差对重建在定位和定量有更大的影响。实验数据也揭示了光学探针峰值波长漂移量在±10nm范围内、动物模型的解剖结构偏差在亚毫米级别以内时都可以得到较理想的定位和定量重建结果。 4.利用自主研发的混合成像系统对胃癌的生物学行为进行定量成像研究。利用生物发光断层分子成像对胃癌原位动物模型实现在体定量分析以及肿瘤模型的长程动态观测，为胃癌的预临床研究提供了新的成像方法和成像工具。通过micro-CT造影成像精确计算出肿瘤的实际体积大小，同时在研究中提出了新颖的低成本欧乃派克时间累积对比增强造影方法，可以实现微小胃癌转移灶的在体定位和定量分析。 5.对干细胞移植治疗缺血性疾病促进血管新生开展了混合成像系统的定量示踪和基于空间血管体积因数SVVF定量评估的成像研究。（1）采用生物发光断层分子成像及超高分辨率micro-CT混合成像系统在三维空间实现干细胞的在体定量示踪以及血管新生的血管灌注分析，实现对干细胞在体空间分布和细胞数量的定量示踪；并根据干细胞的迁移、存活数量和空间分布，进一步交互式实施高分辨的微血管网络密度的定量评估。（2）提出了空间血管体积因数（Spatial VascularVolume Fraction, SVVF）的概念，并将其用于小鼠下肢缺血模型血管新生的定量评估。（3）通过血管体积因数SVVF的系列成像研究发现在时间和空间上血管新生的量化指标，进而探讨性地分析了干细胞移植后旁分泌的作用效果和作用半径。（4）通过多种传统的方法对干细胞移植后的血管新生进行了交叉验证。利用血管铸型验证血管新生的宏观变化情况；通过扫描电镜成像证实了在干细胞移植后促进血管新生作用的不同时间点血管新生的微观结构及发芽情况；通过共聚焦荧光显微成像证实了eGFP转基因小鼠来源的脂肪间充质干细胞在缺血组织的存在性和血管新生的情况；通过激光多普勒成像观测血流灌注的恢复情况。本文提出的SVVF方法以及交叉验证的结果一致发现，脂肪来源的间充质干细胞移植与对照组相比可以明显地增大了血管密度，进而证实脂肪来源的间充质干细胞移植促进了血管新生。综上，在三维空间的血管体积因数成像以干细胞在三维空间的在体示踪存活的数量和空间分布作为反馈信息，进而对血管新生进行定量成像研究。生物发光断层成像及超高分辨率micro-CT混合成像系统在三维空间为基于细胞移植治疗的机制研究和长程监测研究提供了新颖的成像工具和功能评估手段。 本论文的研究涉及到的动物实验均按照动物操作规程执行，并得到了本单位实验动物保护委员会的批准。
[Abstract]:Over the past decade, optical molecular tomography (OMT) has attracted considerable attention due to its excellent performance in the research and application of preclinical major diseases. Bioluminescence tomography and ultra-high resolution micro-CT hybrid imaging system have been widely used in the study of preclinical and clinical malignancies, cardiovascular diseases, neuropathy and other major diseases. Absolute quantitative analysis methods of optical tomography molecular imaging are studied in this paper. Biomedical applications of bioluminescent tomography molecular imaging and ultra-high resolution micro-CT hybrid imaging system for gastric cancer and stem cell transplantation in the treatment of ischemic diseases are systematically studied. In imaging research, the main contents of this thesis include:
1. Bioluminescent tomography molecular imaging system and ultra-high resolution micro-CT hybrid imaging system were constructed, and the bioluminescent tomography molecular imaging system was calibrated quantitatively. Calibration and quantitative calibration of absolute intensity.The field-of-view function is constructed to quantify the luminous flux entering the optical imaging system according to the spatial position difference of optical tomography molecular imaging.The ultra-high resolution micro-CT imaging system is constructed,which lays a foundation for the quantitative study of angiogenesis in the lower limb ischemia model in this paper.
2. Quantitative reconstruction method of bioluminescent tomography molecular imaging is studied. Based on finite element mesh generation method, a strategy of total energy reconstruction is proposed. The feasibility of total energy reconstruction is verified by transplanting known light sources into small animals. The biological parameters reflected by optical probes based on reporter gene system are established. The in vivo quantitative analysis of tumor cells and stem cells by bioluminescent tomography molecular imaging system has been achieved through the intrinsic relationship with the physical parameters of total energy reconstruction in the imaging system. PC-3M-luc-C6 prostate cancer and A549-luc-C8 non-small cell lung cancer cell lines and adipose-derived mesenchymal stem cells were quantified in vivo. The study confirmed the feasibility and applicability of quantitative analysis of cell level.
3. The reconstruction error and its contribution rate of optical tomography molecular imaging under the condition of peak wavelength shift of optical probe and deviation of anatomical structure model are studied. The main source of reconstruction error of optical tomography molecular imaging is analyzed with bioluminescence tomography as an example. (1) On the premise of accurate optical parameters, the reconstruction error is studied. (2) Under the assumption of accurate anatomical structure, the effects of peak wavelength offset of optical probe on the location and quantification of optical reconstruction errors were studied. The results of reconstruction and data analysis show that both of them have a great influence on the localization and quantification of the reconstructed image. When the peak wavelength of the optical probe is below 640 nm, the deviation of the anatomical structure has a greater influence on the localization and quantification of the reconstructed image. Satisfactory localization and quantitative reconstruction results can be obtained when the anatomical structure deviation is within the sub-millimeter level.
4. Quantitative imaging of biological behavior of gastric cancer was studied by using a self-developed hybrid imaging system. Quantitative analysis of animal models of gastric cancer in situ and long-term dynamic observation of tumor models were carried out by using bioluminescent tomography, which provided a new imaging method and imaging tool for preclinical research of gastric cancer. Ro-CT imaging can accurately calculate the actual size of the tumor, and a novel and low-cost Ohnipec time-cumulative contrast-enhanced imaging method is proposed to localize and quantify the metastasis of gastric cancer in vivo.
5. Quantitative tracing of stem cell transplantation for angiogenesis in ischemic diseases and quantitative evaluation of SVVF based on spatial vascular volume factor were carried out. (1) In vivo quantitative identification of stem cells in three-dimensional space was achieved by using bioluminescent tomography and ultra-high resolution micro-CT hybrid imaging system. Tracing and angiogenesis perfusion analysis were used to quantify the spatial distribution and cell number of stem cells in vivo, and high-resolution quantitative evaluation of microvascular network density was carried out interactively according to the migration, survival and spatial distribution of stem cells. (2) Spatial Vascular Volume was proposed. The concept of e-Fraction (SVVF) was applied to quantitatively evaluate angiogenesis in a mouse model of lower limb ischemia. (3) Quantitative parameters of angiogenesis were found in time and space by serial imaging of SVVF, and the paracrine effect and radius of action after stem cell transplantation were discussed. Angiogenesis after stem cell transplantation was cross-validated by traditional methods. The macroscopic changes of angiogenesis were verified by vascular casting; the microscopic structure and germination of angiogenesis at different time points after stem cell transplantation were confirmed by scanning electron microscopy; and the confocal fluorescence was used. Microscopic imaging confirmed the existence and angiogenesis of adipose-derived mesenchymal stem cells from eGFP transgenic mice in ischemic tissues, and the recovery of blood perfusion was observed by laser Doppler imaging. In conclusion, the number and spatial distribution of stem cells traced in vivo in three-dimensional space are used as feedback information in three-dimensional space to quantify angiogenesis. Bioluminescent tomography and ultra-high resolution micro-CT hybrid imaging system provide novel imaging tools and functional evaluation tools for mechanism research and long-term monitoring research based on cell transplantation therapy in three-dimensional space.
The animal experiments involved in this paper are carried out according to the animal operation rules, and have been approved by the Laboratory Animal Protection Committee of this unit.
【学位授予单位】：西安电子科技大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：R318.51;R735.2
本文编号：2200012
[Abstract]:Over the past decade, optical molecular tomography (OMT) has attracted considerable attention due to its excellent performance in the research and application of preclinical major diseases. Bioluminescence tomography and ultra-high resolution micro-CT hybrid imaging system have been widely used in the study of preclinical and clinical malignancies, cardiovascular diseases, neuropathy and other major diseases. Absolute quantitative analysis methods of optical tomography molecular imaging are studied in this paper. Biomedical applications of bioluminescent tomography molecular imaging and ultra-high resolution micro-CT hybrid imaging system for gastric cancer and stem cell transplantation in the treatment of ischemic diseases are systematically studied. In imaging research, the main contents of this thesis include:
1. Bioluminescent tomography molecular imaging system and ultra-high resolution micro-CT hybrid imaging system were constructed, and the bioluminescent tomography molecular imaging system was calibrated quantitatively. Calibration and quantitative calibration of absolute intensity.The field-of-view function is constructed to quantify the luminous flux entering the optical imaging system according to the spatial position difference of optical tomography molecular imaging.The ultra-high resolution micro-CT imaging system is constructed,which lays a foundation for the quantitative study of angiogenesis in the lower limb ischemia model in this paper.
2. Quantitative reconstruction method of bioluminescent tomography molecular imaging is studied. Based on finite element mesh generation method, a strategy of total energy reconstruction is proposed. The feasibility of total energy reconstruction is verified by transplanting known light sources into small animals. The biological parameters reflected by optical probes based on reporter gene system are established. The in vivo quantitative analysis of tumor cells and stem cells by bioluminescent tomography molecular imaging system has been achieved through the intrinsic relationship with the physical parameters of total energy reconstruction in the imaging system. PC-3M-luc-C6 prostate cancer and A549-luc-C8 non-small cell lung cancer cell lines and adipose-derived mesenchymal stem cells were quantified in vivo. The study confirmed the feasibility and applicability of quantitative analysis of cell level.
3. The reconstruction error and its contribution rate of optical tomography molecular imaging under the condition of peak wavelength shift of optical probe and deviation of anatomical structure model are studied. The main source of reconstruction error of optical tomography molecular imaging is analyzed with bioluminescence tomography as an example. (1) On the premise of accurate optical parameters, the reconstruction error is studied. (2) Under the assumption of accurate anatomical structure, the effects of peak wavelength offset of optical probe on the location and quantification of optical reconstruction errors were studied. The results of reconstruction and data analysis show that both of them have a great influence on the localization and quantification of the reconstructed image. When the peak wavelength of the optical probe is below 640 nm, the deviation of the anatomical structure has a greater influence on the localization and quantification of the reconstructed image. Satisfactory localization and quantitative reconstruction results can be obtained when the anatomical structure deviation is within the sub-millimeter level.
4. Quantitative imaging of biological behavior of gastric cancer was studied by using a self-developed hybrid imaging system. Quantitative analysis of animal models of gastric cancer in situ and long-term dynamic observation of tumor models were carried out by using bioluminescent tomography, which provided a new imaging method and imaging tool for preclinical research of gastric cancer. Ro-CT imaging can accurately calculate the actual size of the tumor, and a novel and low-cost Ohnipec time-cumulative contrast-enhanced imaging method is proposed to localize and quantify the metastasis of gastric cancer in vivo.
5. Quantitative tracing of stem cell transplantation for angiogenesis in ischemic diseases and quantitative evaluation of SVVF based on spatial vascular volume factor were carried out. (1) In vivo quantitative identification of stem cells in three-dimensional space was achieved by using bioluminescent tomography and ultra-high resolution micro-CT hybrid imaging system. Tracing and angiogenesis perfusion analysis were used to quantify the spatial distribution and cell number of stem cells in vivo, and high-resolution quantitative evaluation of microvascular network density was carried out interactively according to the migration, survival and spatial distribution of stem cells. (2) Spatial Vascular Volume was proposed. The concept of e-Fraction (SVVF) was applied to quantitatively evaluate angiogenesis in a mouse model of lower limb ischemia. (3) Quantitative parameters of angiogenesis were found in time and space by serial imaging of SVVF, and the paracrine effect and radius of action after stem cell transplantation were discussed. Angiogenesis after stem cell transplantation was cross-validated by traditional methods. The macroscopic changes of angiogenesis were verified by vascular casting; the microscopic structure and germination of angiogenesis at different time points after stem cell transplantation were confirmed by scanning electron microscopy; and the confocal fluorescence was used. Microscopic imaging confirmed the existence and angiogenesis of adipose-derived mesenchymal stem cells from eGFP transgenic mice in ischemic tissues, and the recovery of blood perfusion was observed by laser Doppler imaging. In conclusion, the number and spatial distribution of stem cells traced in vivo in three-dimensional space are used as feedback information in three-dimensional space to quantify angiogenesis. Bioluminescent tomography and ultra-high resolution micro-CT hybrid imaging system provide novel imaging tools and functional evaluation tools for mechanism research and long-term monitoring research based on cell transplantation therapy in three-dimensional space.
The animal experiments involved in this paper are carried out according to the animal operation rules, and have been approved by the Laboratory Animal Protection Committee of this unit.
【学位授予单位】：西安电子科技大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：R318.51;R735.2
【参考文献】
相关期刊论文 前1条
1 ;Optical properties of human normal small intestine tissue determined by Kubelka-Munk method in vitro[J];World Journal of Gastroenterology;2003年09期
本文编号：2200012
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