Data from: Computer assisted detection of axonal bouton structural plasticity in in vivo time-lapse images

The ability to measure minute structural changes in neural circuits is essential for long-term in vivo imaging studies. Here, we propose a methodology for detection and measurement of structural changes in axonal boutons imaged with time-lapse two-photon laser scanning microscopy (2PLSM). Correlative 2PLSM and 3D electron microscopy (EM) analysis, performed in mouse barrel cortex, showed that the proposed method has low fractions of false positive/negative bouton detections (2/0 out of 18), and that 2PLSM-based bouton weights are correlated with their volumes measured in EM (r=0.93). Next, the method was applied to a set of axons imaged in quick succession to characterize measurement uncertainty. The results were used to construct a statistical model in which bouton addition, elimination, and size changes are described probabilistically, rather than being treated as deterministic events. Finally, we demonstrate that the model can be used to quantify significant structural changes in boutons in long-term imaging experiments.

精准检测并量化神经环路内细微结构变化的能力，是开展长期活体成像研究的核心前提。本研究提出一种可针对经延时双光子激光扫描显微镜（two-photon laser scanning microscopy, 2PLSM）成像获取的轴突突触扣结，实现结构变化检测与量化的分析方法。我们在小鼠桶状皮层中开展了2PLSM与三维电子显微镜（3D electron microscopy, EM）的关联分析，结果显示：所提方法的突触扣结检测假阳性/假阴性占比极低（18个检测样本中仅2个假阳性、0个假阴性），且基于2PLSM测得的轴突突触扣结信号权重与其EM实测体积呈显著相关，相关系数r=0.93。随后，我们将该方法应用于一组快速连续成像的轴突样本，以表征测量过程的不确定性。基于该实验结果，我们构建了一个统计模型：该模型以概率方式描述轴突突触扣结的新增、消失及体积变化，而非将其视作确定性事件。最后，我们验证了该模型可用于量化长期成像实验中轴突突触扣结的显著性结构变化。