1. Key Laboratory for Regenerative Medicine of the Ministry of Education, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou, Guangdong, China
2. International Joint Laboratory for Embryonic Development & Prenatal Medicine, Jinan University, Guangzhou, Guangdong, China
3. Department of Microbiology and Immunology, Medical College, Jinan University, Guangzhou, Guangdong, China