ABSTRACT
This study examined the impacts of intrauterine murine cytomegalovirus (MCMV) infection on the long-term learning and memory of offspring.Sexually matured male and female BALB/C mice without MCMV infection were identified by ELISA and then mated.Seventy pregnant mice were randomly divided into the virus group (n=40) and the control group (n=30),in which the pregnant mice were subjected to placenta inoculation of MCMV suspension (1 μL,1 × 106 PFU) or the same amount of cell culture medium,respectively,at gestational age of 12.5 days.Some pregnant mice [virus group (n=20),control group (n=l5)] were sacrificed by cervical dislocation at gestational age of 18.5 days,and the head circumference and brain weight of the mouse fetuses were measured,and the MCMV infection in their brain tissues was detected by PCR.The other pregnant mice [virus group (n=20),control group (n=15)] delivered naturally,and the learning and memory capability of the offspring at 70-day-old was analyzed by Morris water maze test.The results showed that 28.57％ mouse fetuses in the virus group developed viral infection in the brain.Their head circumference and brain weight were significantly reduced as compared with those in the control group (P＜0.01).The Morris water maze test revealed that the mouse offspring in the control group found the platform with straight-line trajectories after training.In contrast,the counterparts in the virus group intended to enter the central area,but looked for the platform with a circular trajectory.And the infected mice exhibited prolonged swimming distance and swimming latency (P＜0.01).It was concluded that:(1) placenta inoculation of MCMV can cause fetal brain infection and intrauterine development retardation; (2) the offspring of MCMV placenta inoculation mice showed a long-term decline in learning and memory capability.
ABSTRACT
The effect of human cytomegalovirus (HCMV) on invasive capability of early pregnant extravillous cytotrophoblasts (EVTs) was investigated in vitro.Primary EVTs were obtained by complex phosphoesterasum digestion and gradient centrifugation from villous tissue aseptically taken from healthy pregnant women.Cytokeratin7 (CK7),vimentin (Vim) and c-erbB-2 were immunocytochemically detected to identify source of cells,and HCMVpp65 antigen was assayed to determine the infection state of primary EVTs by immunocytochemical staining.The EVTs were divided into two groups:control group and HCMV group,and the expression of c-erbB-2,matrix metalloproteinase-2 (MMP-2) and MMP-9 proteins was detected in two groups by immunocytochemistry and Western blotting.Enzymic activity changes of MMP-2 and MMP-9 were tested by gelatin zymography in primary EVTs infected with HCMV.The invasion of primary EVTs was detected by cell invasion assay in vitro after they were infected by HCMV.The cell source identification showed that the cells obtained were highly-pure primary EVTs,and primary EVTs could be infected by HCMV.Primary EVTs could express c-erbB-2,MMP-2 and MMP-9 proteins,and as compared with control group,the protein expression was decreased significantly in HCMV groups (P＜0.05).Primary EVTs could secrete active MMP-2 and MMP-9 in vitro,and the activity of two MMPs was decreased significantly in HCMV groups (P＜0.05).The in vitro cell invasion assay showed that the number of primary EVTs permeating Matrigel in HCMV group was decreased (P＜0.05).We are led to conclude that HCMV can infect primary EVTs and inhibit their invasion capability,suggesting that the impaired EVT's invasion capability might be related to the abnormal expression of c-erbB-2,MMP-2and MMP-9 proteins.
ABSTRACT
Human trophoblast cells were isolated and cultured in vitro in order to investigate possible pathogenesis of intrauterine infection caused by HCMV.Trophoblast cells were obtained by compound enzymes digestion and discontinuous percoll gradient.Cells and purity were identified by using immunocytochemistry assay with anti-CK7,Vim and β-hCG antibodies.HCMV AD169 strain replication in isolated trophoblast cells and cell apoptosis were detected at different time points post infection(p.i.).The results showed that highly purified trophoblast cells were obtained.Specific virus replication was increased dramatically at the 24th h p.i.,and then increased slowly during 48 h and 72 h.Apoptosis rate of trophoblast cells infected with HCMV was(34.68±3.14)% at 24th h p.i.,while that in control group was(15.32±2.34)%(P<0.05).It was suggested that highly purified trophoblast cells can be isolated by the simplified cell purification method.HCMV can infect human trophoblast cells,and be quickly replicated,resulting in the accelerated apoptosis of human trophoblast cells during early time.