Related Experiment Video
Updated: Aug 2, 2026
Use of In vivo Imaging to Monitor the Progression of Experimental Mouse Cytomegalovirus Infection in Neonates
Published on: July 6, 2013
Human Cytomegalovirus IE2 Disrupts Neural Progenitor Development and Induces Microcephaly in Transgenic Mouse
Delei Niu1, Xianjuan Zhang1, Shuyun Zhang1
1Department of Pathogenic Biology, College of Basic Medicine, Qingdao University, Qingdao, 266000, Shandong, China.
Abstract:
Human cytomegalovirus (HCMV) is a significant contributor to congenital birth defects. Limited by the lack of animal models, the pathogenesis of neurological damage in vivo caused by HCMV infection and the role of individual viral genes remain to be elucidated. Immediate early (IE2) protein may play a function in neurodevelopmental problems caused by HCMV infection. Here, this study intended to investigate IE2's long-term effects on development of the brain in IE2-expressing transgenic mice (Rosa26-LSL-IE2+/-, Camk2α-Cre) aimed to observe the phenotype of postnatal mice. The expression of IE2 in transgenic mice was confirmed by PCR and Western blot technology. We collected mouse brain tissue at 2, 4, 6, 8, and 10 days postpartum to analyze the developmental process of neural stem cells by immunofluorescence. We discovered that transgenic mice (Rosa26-LSL-IE2+/-, Camk2α-Cre) can reliably produce IE2 in the brain at various postpartum phases. Furthermore, we also observed the symptoms of microcephaly in postnatal transgenic mice, and IE2 can damage the amount of neural stem cells, prevent them from proliferating and differentiating, and activate microglia and astrocytes, creating an unbalanced environment in the brain's neurons. In conclusion, we demonstrate that long-term expression of HCMV-IE2 can cause microcephaly through molecular mechanisms affecting the differentiation and development of neural stem cells in vivo. This work establishes a theoretical and experimental foundation for elucidating the molecular mechanism of fetal microcephaly brought by HCMV infection in throughout the period of neural development of pregnancy.
Insights
Human cytomegalovirus (HCMV) immediate early protein 2 (IE2) expression in transgenic mice caused microcephaly. IE2 disrupts neural stem cell development, leading to developmental brain defects.
Area of Science:
- Neurovirology
- Developmental Neuroscience
- Immunology
Background:
- Human cytomegalovirus (HCMV) is a leading cause of congenital birth defects.
- The precise mechanisms of HCMV-induced neurological damage and the roles of specific viral genes in vivo are not fully understood.
- The immediate early (IE2) protein of HCMV is a potential factor in HCMV-related neurodevelopmental disorders.
Purpose of the Study:
- To investigate the long-term effects of HCMV IE2 protein expression on brain development in a transgenic mouse model.
- To elucidate the role of IE2 in neural stem cell proliferation, differentiation, and the neuroinflammatory response.
- To establish an in vivo model for studying HCMV-induced microcephaly.
Main Methods:
- Generation of IE2-expressing transgenic mice (Rosa26-LSL-IE2+/-, Camk2α-Cre).
- Confirmation of IE2 expression using PCR and Western blot.
- Analysis of neural stem cell development, proliferation, and differentiation via immunofluorescence in postnatal mouse brain tissue (days 2-10).
- Assessment of microglial and astrocyte activation.
Main Results:
- Transgenic mice reliably expressed IE2 in the brain throughout the early postpartum period.
- Postnatal IE2 expression led to observable microcephaly in transgenic mice.
- IE2 expression impaired neural stem cell proliferation and differentiation.
- IE2 induced activation of microglia and astrocytes, indicating neuroinflammation.
Conclusions:
- Long-term expression of HCMV IE2 in vivo causes microcephaly by disrupting neural stem cell differentiation and development.
- This study provides a foundation for understanding the molecular mechanisms underlying HCMV-associated fetal microcephaly during neural development.
