Human PGF adenoviral particles

Here, the researchers investigated the effects of placental growth factor (PGF) overexpression and hyperoxia on lung development in neonatal rats and determined whether anti-PGF antibodies could improve hyperoxia-mediated lung development disorders in neonatal rats. After 7 days of normoxic culture, Normoxia neonatal rats were intraperitoneally or intratracheally injected with saline, adenovirus negative control (Ad-NC), or adenovirus-PGF (Ad-PGF) to form Normoxia groups, Normoxia + Ad-NC groups, and Normoxia + Ad-PGF groups. Hyperoxic neonatal rats were intraperitoneally injected with saline or anti-PGF antibodies to form Hyperoxia groups and Hyperoxia + anti-PGF groups. The results showed that the levels of PGF and its receptor Flt-1 in the lung tissues of neonatal rats in the Normoxia + Ad-PGF group and the Hyperoxia group were significantly increased. PGF overexpression in these groups led to lung injury in neonatal rats, and anti-PGF antibody treatment could significantly cure the lung injury caused by hyperoxia. In addition, PGF overexpression significantly increased TNF-α and Il-6 levels in bronchoalveolar lavage fluid (BAL) in both Normoxia + Ad-PGF and Hyperoxia groups. Immunohistochemical analysis showed that PGF overexpression and hyperoxia treatment significantly increased the expression of angiogenic marker CD34. However, its expression was significantly reduced after administration of anti-PGF antibody (compared with the hyperoxia control group). In conclusion, PGF overexpression impairs lung development in neonatal rats, while inhibition of its expression using anti-PGF antibody improves lung development.

Here, the researchers took lung tissues of newborn rats for IHC detection of CD34 expression, and the results showed that the CD34 expression level in lung tissues of rats in the Normoxia + Ad-PGF group was significantly higher than that in the Normoxia + Ad-NC group (Figure 1). In addition, the CD34 expression level in lung tissues of rats in the hyperoxia group was higher than that in the Normoxia group, while the CD34 expression level in lung tissues of rats in the Hyperoxia + anti-PGF group was significantly lower than that in the Hyperoxia group.

Figure 1. CD34 expression was detected by immunohistochemistry in lung tissues from newborn rats of each indicated group (n=10). (Zhang Z, et al., 2020)