part i basic concepts of stem cells1 primordial germ cells and germ line stem cells ji wu, zhuxia zheng, hu wang, xingxing mei, xingbao ding and xiaoyong li2 human amniotic fluid-derived and amniotic membrane-derived stem cells limei yu3 mesenchymal stem cells and their immunomodulatory properties lianming liao and robert chunhua zhao4 induced pluripotent stem cell, a rising star in regenerative medicine yihuan mao, yukai wang, libin wang and qi zhou5 stem cells and hematopoietic cell engineering xiaoyan xie, yanhaa li, yanxun sun, jin zhang, fang fang, wen yue and xuetao pei6 signaling pathways regulating stem cells xingting guo, jun chen, zhaohui li and rongwen xi7 the concept of mesenchymal stem cell system: bring more insights into functional research of mscs shihua wang and robert chunhua zhao8 human neural development and human embryonic stem cell neural differentiation yunbo qiao and naihe jing9 molecular imaging: the key to advancing stem cell therapy .. ningning he and zongjin li10 stem cell and peripheral nerve regeneration chengbin xue, sheng yi and xiaosong gu11 biomaterial-assisted stem cell engineering for tissue construction and regeneration xiaojun yan, bingjie wang, chunxiao qi, jonathan joseph lowrey and yanan dupart ii clinical translation12 stem cells in the treatment of myocardial infarction and cardiomyopathy robert j. henning13 mesenchymal stem cell therapy for bladder dysfunction hong j. lee and sung sik choi14 mesenchymal stem cells in cancer therapy nedime serakinci and mahmut cerkez ergoren15 stem cell therapy for gvhd nayoun kim and seok-goo cho16 clinical application and molecular mechanism of multipotent stem cell therapy for liver disease xia zhou, lina cui, yongquan shi and ying han17 stem cell therapy for cartilage defects philip s. pastides and wasim s. khan18 stem cell transplantation for crohn's disease jie liang and kaichun wu19 stem cell therapy for optic nerve regeneration huasong gao and jianhong zhu20 stem cells and spinal cord regeneration xinhua zhang, sheng yi and xiaosong gu21 cell transplantation therapy for diabetes mellitus: from embryonic stem cells to transdifferentiation of adult cells . xinhua xiao and yiiing liu