ABSTRACT
Objective To explore the effect of HeLa cells infected with Coxsackie virus B3 (CVB3) on the changes of mTOR signal pathway under different nutritional conditions.Methods The HeLa cells were cultured under conventional culture and serum starvation culture.(1) For the conventional method,the medium with 10 g/L fetal bovine serum was added for 24 h after the Hela cells were fused into 40％ to 50％,and the medium was changed on the next day,then the virus group was infected with CVB3 of 50％ tissue culture infective dose (TCID50).However,the control group was cultured by 2 g/L fetal bovine serum.(2) For the serum starvation method,HeLa cells were cultured with the medium without fetal bovine serum for 24 h.Then the virus group was infected with CVB3 of TCID50.The cells in control group were cultured by 2 g/L fetal bovine serum.Cell morphology changes were observed by inverted microscope,and the expressions of the mTOR,p70S6K mRNA were detected with Real-time PCR at 3 h,6 h,9 h,12 h,24 h respectively in both conventional culture and serum starvation groups.Results The expressions of mTOR and p70S6K mRNA were lower in the virus group than those in control group at 12 h and the 24 h (all P ＜0.05) in the conventional culture group.And the expressions of mTOR and p70S6K mRNA in the virus group were lower than those in the control group at every time points (all P ＜ 0.05) in serum starvation group.The expressions of mTOR and p70S6K mRNA in group with serum starvation virus and the control groups were higher than those in conventional culture group in all time points,but only the expressions of mTOR mRNA were significantly different between the 2 groups (all P ＜0.05),however,the expressions of p70S6K mRNA had no significant difference between the 2 groups (all P ＞ 0.05).Conclusion CVB3 may be able to down-regulate the expressions of mTOR and p70S6K mRNA.
ABSTRACT
<p><b>OBJECTIVE</b>To study the safety and immunogenicity of the Bilive combined hepatitis A and B vaccine produced by Sinovac Biotech Co., Ltd.</p><p><b>METHODS</b>Samples were selected from first year students of a senior high school (adults group) and first to fifth grade 1-5 students of 3 primary schools (children group). Those who were susceptible to both hepatitis A virus (HAV) and hepatitis B virus (HBV), HAV only or HBV only were assigned to group AB, A and B respectively and were vaccinated with three doses (0, 1 and 6 month schedule) of Bilive combined hepatitis A and B vaccine, inactivated hepatitis A vaccine and recombined hepatitis B vaccine respectively. The dosage for adult group was 500 U hepatitis A antigen and/or 10 micro g hepatitis B surface antigen and the dosage for children group was half the dosage of adult group. The potential adverse effects were observed within 72 hours after vaccination. Serum samples were collected for testing anti-HAV and anti-HBs at month 2 and 7 after the initial dose.</p><p><b>RESULTS</b>The rates of local adverse effects were 0.58% and 2.56% in children AB group and adults AB group and the general adverse effects rates were 9.88% and 5.45% respectively. Both local and general adverse effect rates were not significantly different to the control group. The sero-conversion rate of anti-HAV in children and adults AB group reached 100%, one month after 3 doses. The geometric mean titer (GMTs) reached 33,910 mIU/ml and 23,435 mIU/ml respectively, significant higher than that in control group (group A). The sero-conversion rates of anti-HBs were 97.30% and 96.63%, and GMTs were 103 mIU/ml and 102 mIU/ml in children and adults AB group respectively. No significant difference on sero-conversion and GMT was observed when compared with control group.</p><p><b>CONCLUSION</b>The Bilive combined hepatitis A and B vaccine had good safety profile, and the immunogenicity both on anti-HAV and anti-HBs was similar to that of separated components.</p>