Recently a research team led by Luo Minhua of Wuhan Institute of Virology (WIV) has made big progress in the establishment of human neural stem cell system and the preliminary studies of its infection by human cytomegalovirus (HCMV). The research results have been published on Journal of Virology.

Congenital HCMV infection is one common cause of birth defects, including mal-development of central nervous system (CNS). Congenital HCMV infection happens in early stage of pregnancy. Its effects are much worse than infections at later pregnancy period, including severe brain damage, such as cerebellum malformation, etc. Fetal brain HCMV infection mostly happens in sub-ventricular zone (SVZ), and the affected cells are mostly neural stem cells / precursor cells (NPCs). Therefore, in this research project, the team rebuilt extracorporal NPCs model of HCMV infection to further investigate and compare NPCs HCMV infection of cells with different embryonic ages, and the influence of longtime extracorporal culture on HCMV infection. It is found that newly separated NPCs are completely admissible for HCMV infection. There is no obvious difference among HCMV infection indexes. This indicates that there is no difference between individual infections. Comparison of HCMV infections of earlier generation NPCs (no more than 9 generations) and later generation NPCs (more than 11 generations) indicates that later generation NCPs have faster CPE speed, release more virus particles, and have different virus gene expression level and higher virus penetration efficiency. It is obvious that later generation NPCs are more susceptible to HCMV infection.

Previously, researchers often use NPCs of no more than 9 generations in HCMV infection research. No people have ever tried NPCs of more than 9 generations in HCMV infection research. This research has systematically investigated the difference of HCMV infections on earlier generation and later generation NPCs, explained the differences of cell form, virus gene expression and virus particle release, explored the mechanism behind such difference, and found that it might be caused by difference of NPCs separation status and virus receptor’s expression. This research can offer theoretical basis for clinical research. It reveals that in later infection period, HCMV has severer damage on fetal brain neural cells. Therefore it is necessary to treat the pregnant women infected by HCMV as soon as possible. Extracorporal culture of human neural stem cell and the research on its susceptibility to HCMV are very valuable for neurobiology, stem cell and HCMV infection mechanism researches. This research project has won funding of NSFC (Natural Science Foundation of China).