Search

Objectives: To explore the association between assisted reproductive technology (ART) and birth weight discordance in twins (BWDT)., Methods: A retrospective analysis was conducted on twin infants born between January 2011 and December 2020 at the Third Affiliated Hospital of Guangzhou Medical University, with complete basic birth data. The impact of ART on the occurrence of BWDT was identified by the multivariate logistic regression analysis., Results: A total of 3 974 pairs of twins were included, with 1 431 conceived naturally and 2 543 through ART. Neonates in the ART group had higher birth weights than those in the naturally conceived group ( P <0.001). The incidence of BWDT was lower in the ART group compared to the naturally conceived group (16.17% vs 21.09%, P <0.001). The multivariate logistic regression analysis, adjusting for confounding factors such as maternal age, parity, pre-pregnancy body mass index, gestational diabetes, hypothyroidism, gestational age, and chorionic properties, showed no significant difference in the risk of BWDT between the ART and naturally conceived groups ( P >0.05)., Conclusions: ART is not associated with the risk of BWDT.

Objective: To analyze the epidemiological and etiological characteristics of diarrheal disease among children under 5 years of age in Guangdong province, in 2012., Methods: 64 hospitals in 21 cities were chosen as the diarrheal syndromic surveillance sites, of which 14 hospitals were selected to carry out etiological surveillance among children under 5 years of age, including isolation and culture of both Vibrio cholera and Shigella as well as nucleic acid detection of rotavirus and norovirus by PCR. Descriptive method was used to analyze data from syndromic and etiological surveillance programs on diarrheal, from 1932 parents of the children., Results: In 2012, the outpatient attendance rate on diarrheal among children under 5 years was 0.8%. The proportion of diarrheal in children under 5-year-olds was 63.5%, among the total number of diarrheal outpatients at the outpatient clinics under surveillance program. The morbidity of infectious diarrhea was 1454.5/10 million in children under 5 years of age. A total number of 1932 specimens were collected from children under 5 years of age, in the outpatient department. Among these specimens,Vibrio cholera appeared all negative but one was Shigella positive and proved to be Sh. sonnei. The positive rates of rotavirus and norovirus were 14.1% (273/1932)and 16.9% (326/1932). Both rotavirus and norovirus were found in 24 specimens, with a positive rate as 1.2% . 112 specimens were successfully gene sequenced for rotavirus, of which 33.9% as G1[P8] genotype, 25.9% as G9[P8], 12.5% as G2[P4] and 9.8% as G3[P8] respectively. 90 specimens were successfully gene-sequenced for norovirus, of which 76.7% as G II.4 genotype. Genetic subtypes of G II. 4/2006b, accounted for 50.0% and could be detected around the year except for June and December. New G II. 4/Sydney Strain&#95;2012 was first detected in August and became the predominant in December. In addition, 5 specimens belonged to G I genotype with other 16 subtypes of G II., Conclusion: Results from our study proved that children under 5 years of age belonged to high-risk group for diarrheal disease in Guangdong province. Rotavirus and norovirus were both diverse in terms of genome.

Objective: To explore the correlation of serum ferritin (SF) and systemic onset juvenile idiopathic arthritis (SOJIA) so as to determine the prognostic values of SF for SOJIA., Methods: All samples were collected from 92 juvenile idiopathic arthritis (JIA) patients at Beijing Children's Hospital between February 2005 to September 2012. Their age range was 2-15 years. There were macrophage activation syndrome (MAS, n = 25), polyarticular JIA (n = 33) and oligoarticular JIA (n = 30). And 47 healthy children and another 30 with acute infective diseases were selected as control groups respectively. Blood samples were collected and SF was measured in different disease phases.Other parameters include leucocyte, hemoglobin, platelet, C-reactive protein and erythrocyte sedimentation rate.Statistics of SF level at different groups as well as at different disease phases were performed., Results: The SF level of active phase SOJIA patients was significantly higher (P < 0.01) than that in Other groups. And its level in the active phase of SOJIA was significantly higher than that in patients during the recovery phase. The SF level in patients with MAS was significantly higher than that in those without MAS., Conclusion: Correlated with the course of SOJIA, the level of SF may judge the disease activity and predict the outcomes of SOJIA.

Objective: To study the effects of post-discharge formula (PDF) for preterm infants, breast milk (BM) and term infant formula (TF) on increase rates of body weight, length and head circumference in preterm and low-birth-weight infants (PLBWIs) from discharge to 3 months after birth, and to provide a reference for the choice of feeding pattern for PLBWIs., Methods: A total of 407 PLBWIs discharged from the newborn departments of ten hospitals in Guangzhou City and Foshan City in Guangdong Province, China were chosen for this study. According to feeding pattern, they were assigned to three groups: PDF-fed (n=258), BM-fed (n=58) and TF-fed (n=91). Their body weight, length and head circumference were measured at 3 months after birth, and the increase rates of growth indices relative to baseline values (at birth) were calculated and compared., Results: At 3 months after birth, the PDF-fed group had significantly greater body weight, length and head circumference than the BM-fed and TF-fed groups (P<0.05). The increase rates of body weight and length were significantly higher in the PDF-fed group than in the BM-fed and TF-fed groups (P<0.05)., Conclusions: Compared with those fed with BM and TF after discharge, the PDF-fed PLBWIs have higher increase rates of body weight and length and show greater body weight and length at 3 months after birth. However, further study is needed to investigate the long-term effects.

Objective: To investigate the possibility of directional differentiation of human adipose stem cells (hADSCs) into endothelial cells (EC), so as to provide seed cells for tissue engineered vessels., Methods: hADSCs were isolated from human adipose tissue by collagenase digestion, cultured and amplified by adherence to flasks. Then hADSCs were directionally induced to differentiate into EC by a combination of fibronectin (FN), endothelial cells support liquid (EGM2-MV) containing various growth factors and high concentration of VEGF165 (50 ng/ml). Then, the cells morphology, phenotype and function were identified., Results: Highly homologous hADSCs were obtained, and then hADSCs were directionally differentiated into EC. CD31 and CD34, the specific markers for EC, and vascular endothelial growth factor receptor (KDR) were positive by immunohistochemical staining and RT-PCR. In addition, unique Weibel-Palade bodies in EC were observed under transmission electron microscope. Functionally, hADSCs could swallow Dil-Ac-LDL and form tube-like structures in matrigel after endothelial differentiation., Conclusions: hADSCs can be successfully induced to differentiate into endothelial cells in vitro.

Objective: To explore the toxicity of joint exposure to diazinon, propoxur and bisphenol A on phagocytosis., Methods: Flow cytometer was employed to detect the influence of diazinon and bisphenol A, propoxur and bisphenol A in mixture (mixed according to ratio of IC(50)) on mouse macrophage RAW264.7 cells' function to phagocyte fluorescent microspheres, adopting the percentage of phagocytic cells (PP) and the phagocytic index (PI) as measurement indicators. The final concentrations of mixture of diazinon and bisphenol A were (0.4 + 0.1), (3.6 + 0.7), (36.2 + 7.2), (43.4 + 8.7), (52.1 + 10.4), (62.5 + 12.5), (75.0 + 15.0) µg/ml; while those of mixture of propoxur and bisphenol A were (0.2 + 2.0 × 10(-2)), (2.4 + 0.2), (23.7 + 2.0), (35.6 + 3.0), (53.3 + 4.4), (80.0 + 6.7), (120.0 + 10.0) µg/ml. Then based on the dose-response relationship, a 2 × 2 factorial design was then carried out among different doses of mixture with statistical significance to statistically evaluate the interaction between diazinon and bisphenol A, propoxur and bisphenol A., Results: After the joint exposure, compared to the control group (PP = (23.6 ± 2.2)%; PI = 0.36 ± 0.03), any dose of the mixture of diazinon and bisphenol A ((52.1 + 10.4), (62.5 + 12.5), (75.0 + 15.0) µg/ml) could significantly increase the levels of PP ((29.0 ± 1.4)%, t = 3.89, P < 0.05; (30.2 ± 2.3)%, t = 4.74, P < 0.05; (35.0 ± 3.4)%, t = 8.21, P < 0.05) and PI (0.43 ± 0.03, t = 3.86, P < 0.05; 0.41 ± 0.02, t = 2.95, P < 0.05; 0.46 ± 0.03, t = 5.34, P < 0.05); while that of propoxur and bisphenol A ((35.6 + 3.0), (53.3 + 4.4), (80.0 + 6.7), (120.0 + 10.0) µg/ml) reduced the levels of PP ((20.6 ± 1.1)%, t = -3.00, P < 0.05; (20.2 ± 1.0)%, t = -3.42, P < 0.05; (19.4 ± 1.3)%, t = -4.23, P < 0.05; (18.8 ± 2.1)%, t = -4.81, P < 0.05) and PI (0.31 ± 0.01, t = -4.75, P < 0.05; 0.31 ± 0.01, t = -4.58, P < 0.05; 0.30 ± 0.01, t = -4.92, P < 0.05; 0.27 ± 0.02, t = -7.80, P < 0.05) on the contrary. The 2 × 2 factorial design was carried out between the mixture of diazinon (60.0 µg/ml; PP = (28.5 ± 3.4)%; PI = 0.49 ± 0.07) and bisphenol A (12.0 µg/ml; PP = (35.7 ± 2.7)%; PI = 0.67 ± 0.07), and the mixture of propoxur (48.0 µg/ml ; PP = (28.1 ± 2.2)%; PI = 0.48 ± 0.04) and bisphenol A (4.0 µg/ml; PP = (34.4 ± 2.7)%; PI = 0.59 ± 0.07). The mixture of diazinon and bisphenol A (PP = (30.4 ± 1.4)%, F(interaction) = 6.22, P < 0.05; PI = 0.53 ± 0.03, F(interaction) = 7.35, P < 0.05) and the mixture of propoxur and bisphenol A (PP = (27.5 ± 4.1)%, F(interaction) = 4.56, P < 0.05; PI = 0.46 ± 0.08, F(interaction) = 11.13, P < 0.05) both showed a significant antagonistic interaction on phagocytosis of RAW264.7 cell., Conclusion: It is suggested that the interactions between diazinon & bisphenol A and propoxur & bisphenol A both played the antagonistic role on phagocytic function of macrophages in vitro.

Objective: To research the co-infections of HIV and human herpesvirus 8 (HHV8) in Uygur high-risk groups of HIV infection in a city Xinjiang., Methods: All 468 Uygurs at high HIV risk registered in the sentinel monitoring system in 2006 were enrolled in this study. The antibodies to HHV8 latency-associated nuclear antigens 1 (LANA1), lytic antigens open reading frame 65 (ORF65) and K8.1 were measured by enzyme linked immunosorbent assay (ELISA). Chi-square test and non-condition Logistic regression model were used for data analysis., Results: Of 468 sera samples, 67 (14.3%) were HIV and HHV8 co-infection positive.Male's HIV and HHV8 co-infection rate (22.6%, 54/239) was higher than the female's (5.7%, 13/229) (chi(2) = 27.285, P < 0.001). For those above 24 year old, HIV and HHV8 co-infection rate (15.8%, 65/412) was higher than the < 24 year old group's (3.6%, 2/56) (chi(2) = 5.987, P = 0.014). The group of Elementary school and illiterate people's HIV and HHV8 co-infection rate (20.7%, 40/193) was higher than the junior middle school and the above culture (9.8%, 27/275) (chi(2) = 10.999, P = 0.001). For the unmarried people, the co-infecting rate of HIV and HHV8 for the married, the cohabitants, the divorced or the widowers were 16.9% (14/83), 12.2% (42/345), 27.5% (11/40) respectively. There was significantly statistical difference among three marital status (chi(2) = 7.399, P = 0.025). Injecting drug users' HIV and HHV8 co-infection rate (26.5%, 50/189) was higher than non-injecting drug users' (6.1%, 17/279) (chi(2) = 38.083, P < 0.001), and stratified by gender, OR(M-H) was 4.207 (95%CI: 1.529 - 11.578). Via non-condition logistic stepwise regression analysis, only injecting drug use entered model, compared with non-injecting drug users, injecting drug users were more dangerous for HIV and HHV8 co-infecting (OR = 5.544; 95%CI: 3.081 - 9.975)., Conclusion: The HIV and HHV8 co-infection rate was higher in the Uygurs at high HIV risk in Xinjiang. Injecting drug use is a risk factor of the HIV and HHV8 co-infection, which might be one of routes of HIV and HHV8 co-infection among this group.

Objective: To investigate the effect of adenovirus vector encoding human vascular endothelial growth factor receptor-2 (hVEGFR-2 or hKDR) on breaking the immune tolerance and inducing immunity against murine hepatocellular carcinomas., Methods: Human and mouse KDR cDNA were cloned from human umbilical vein endothelial cells (HUVEC) and C57BL/6 mouse embryo cells respectively using RT-PCR, and then Ad hKDR and Ad mKDR were constructed. Seven days after immunization of the mice with Ad hKDR or Ad mKDR, an analysis of cytotoxic activity of antigen-specific cytotoxic T lymphocytes (CTL) was made by lactate dehydrogenase (LDH) release assay, in which splenocytes of the immunized mice acted as effectors and Hepa 1-6/mKDR cells as the targets. In addition, the survival of the mice immunized with Hepa 1-6 hepatoma cells was checked., Results: Seven days after immunization, the 6 h killing activities of CTL elicited by the Ad hKDR were 84.3%+/-6.7%, 71.5%+/-5.2%, and 44.6%+/-4.7% at the ratio of the effectors:targets (E:T) of 100:1, 50:1, and 25:1, respectively. Correspondingly, the CTL activities by Ad mKDR were 65.2%+/-6.1%, 46.7%+/-5.0%, and 22.6%+/-3.7%. Sixty percent of the Ad hKDR-immunized mice with 5*10(6) Hepa 1-6 hepatoma cells were still alive two months after the inoculation, whereas just 40% of the Ad mKDR-immunized mice with 2*10(6) Hepa 1-6 cells survived two months. When CD8+ or CD4+ T lymphocytes were deleted in the mice the above mentioned CTL activities and protection of the mice from tumors disappeared., Conclusion: Adenovirus vector-mediated xenogeneic KDR can effectively break the immune tolerance to hepatocellular carcinomas in an animal model and induce a strong antigen-specific T cell response, which is dependent on CD8+ and CD4+ T cells.

Background & Objective: Primary hepatocellular carcinoma (HCC) is a common malignant tumor. Up to date, no effective treatment for HCC is available. This study was to investigate the synergic effect of adenoviral vector-encoding xenogeneic alpha-fetoprotein (AFP) and interferon-gamma (IFN-gamma) on the immunity against HCC in mice., Methods: IFN-gamma gene was cloned using reverse transcription-polymerase chain reaction (RT-PCR). Replication-defective adenovirus encoding both human AFP and murine IFN-gamma was constructed. The cytotoxic activity of antigen-specific cytotoxic T lymphocytes (CTLs) was detected 7 days after the intradermal immunization of C57BL/6 mice with Ad-hAFP, Ad-IFN-gamma or Ad-hAFP/IFN-gamma using standard (51)Cr release assay. The survival of mice after the subcutaneous inoculation of 5x10(6) hepatoma Hepa 1-6 cells was checked., Results: The cytotoxic activity of CTLs elicited by Ad-hAFP/IFN-gamma was much stronger than that by Ad-hAFP or Ad-IFN-gamma alone. At an effector:target (E:T) ratio of 10:1, the cytotoxic activities of CTLs in Ad-hAFP/IFN-gamma, Ad-hAFP, and Ad-IFN-gamma groups were (43.8+/-5.5)%, (28.2+/-3.2)%, and (12.8+/-1.9)%, at a ratio of 30:1, were (79.6+/-6.4)%, (51.9+/-4.3)%, and (15.6+/-2.3)%, and at a ratio of 90:1, were (88.2+/-6.3)%, (62.5+/-4.8)%, and (26.5+/-2.4)%, respectively. The tumor formation rates were 80% in Ad-hAFP-immunized mice and 100% in Ad-IFN-gamma-immunized mice at 2 months after inoculation with Hepa1-6 cells; no tumor formed in Ad-hAFP/IFN-gamma-immunized mice, and all mice in this group survived during two-month observation., Conclusion: Ad-hAFP can efficiently induce immunity against HCC in mice, and IFN-gamma enhances such an effect.

Objective: To establish the 3T3 mouse fibroblast neutral red uptake (NRU-PT) phototoxicity test method, and evaluate the practicality of the method in detecting potential phototoxicity of the cosmetic products., Methods: Fifteen phototoxic and 9 non-phototoxic chemicals were tested in our laboratories, the phototoxic potential of the test chemicals was evaluated in a prediction model in which either the photo irritation factor (PIF) or the mean photo effect (MPE) was compared with the coherence and sensitivity of the method. 20 kinds of functional cosmetics were detected and the results were analyzed by the 3T3 NRU-PT in vitro and Guinea pig skin phototoxicity test (in vivo)., Results: Both PIF and MPE of the chemicals were highly reproduced, and the correlation between in vitro and in vivo data was almost perfect. All the non-phototoxic provided a negative result, while 14 of the 15 phototoxic tested chemicals gave clear positive results. For cosmetics, the correlation between in vitro and in vivo data was consistent., Conclusion: The 3T3 NRU PT test was established successfully, it should be used as a good alternative method for assessing the phototoxic potential of the chemicals and cosmetics in China.

Objective: To develop a more economic and applicable substitute for modification of dendritic cells (DCs) by capped mRNA in induction of anti-tumor immunity., Methods: Four DNA plasmids as templates of mRNA in vitro transcription were constructed: pmRNA luciferase (Luc), pmRNA internal ribosomal entry site (IRES)-Luc, pmRNA ovalbumin (OVA), and pmRNA IRES-OVA. The translational efficiency of uncapped-Luc, capped-Luc, or IRES-Luc mRNA in murine DCs was detected via a Luc reporter system. Nine C57BL/6 mice were divided into 3 equal groups to be injected intraperitoneally with DCs transfected with IRES-OVA or capped-OVA mRNA and untreated DCs respectively, 1 weeks later the mice were injected with splenocytes wrapped with the target peptide or control peptide labeled by CFSE, and 4 hours later the mice were killed and suspension of splenocytes was made to test the activity of cytotoxic lymphocytes (CTLs). Another 30 mice were divided into 3 equal groups to undergo immunization by DCs as mentioned above, 1 week later mice melanoma cells of the line MO5 stably expressing OVA were injected the caudal vein, and 3 weeks later the mice were killed and their lungs were taken out to observe the metastasis of tumor, using OVA as a target antigen., Results: Insertion of IRES into upstream of gene of interest in mRNA transcriptional templates didn't affect the yield of mRNA in vitro transcription. The level of Luc activity expressed by IRES-Luc mRNA in the DCs was 20 times higher than that by expressed by Uncapped Luc mRNA, and one time higher than that by Capped-Luc mRNA 8 h after transfection of DC. Expression of Luc could be detected up to 96 h after the transfection with IRES-Luc and Capped-Luc mRNA. Four hours after the injection of peptides the CTL activity of the mice immunized with DCs pulsed with Capped-OVA mRNA was (28 +/- 3)%, not significantly different from that of the mice immunized with DCs pulsed with IRES-OVA mRNA [(32 +/- 4)%, P > 0.05]. Mata static melanoma nodules could be seen in all control mice, only one mouse of the Capped-OVA mRNA group, and none of the mice of the IRES-OVA mRNA group., Conclusion: IRES-containing tumor-associated antigen (TAA) mRNA as a more economic and applicable substitute fully replaces Capped-TAA mRNA for mRNA-based DC vaccines and DCs pulsed with IRES-containing TAA mRNA induces the same effective antigen-specific cellular response as the DCs pulsed with Capped-TAA mRNA.

Objective: To explore a flow cytometry (FCM)-based method for discriminating aneugen- or clastogen-induced micronuclei., Methods: Cells were stained with anti-CD71-FITC and PI, and the PI fluorescent signal intensity of micronucleated reticulocyte (MN-RET) in the peripheral blood of NIH mouse treated with COL or CP was detected by flow cytometry., Results: The ratio of the median of the intensity of MN-RET fluorescent signals to that of nucleated cell was low in the cyclophosphamide treated mouse, while the median was high in the colchicine treated mouse., Conclusion: The flow cytometry-based micronucleus assay can be used to discriminate primarily smaller MN induced by the clastogen exposure from the larger MN induced by an aneugen.

Objective: To investigate the enhanced effect of bone marrow-derived dendritic cells (DC) pulsed with SVYDFFVWL, a MHC class I peptide located in 180-188 amino acid residues of human melanoma-associated antigen tyrosinase- related protein 2 ( hTRP2) on the immunity against melanomas elicited by adenovirus encoding hTRP2 (Ad hTRP2)., Methods: The mice were intradermally immunized with Ad hTRP2, and three weeks later with Ad hTRP2 or DC/SVYDFFVWL once more. Analysis of CTL killing activity and IFN-gamma-producing CD8 + T cells in the total CD8 + T cells of spleen were made using in vivo CTL and intracellular staining of IFN-gamma, respectively. Additionally, the survival of mice was checked after the subcutaneous inoculation with mouse melanoma B16. F10 cells., Results: The 6 h CTL killing and IFN-gamma producing CD8 +T cells in the total CD8 ' T cells of spleens were 68. 40%+/-5. 50% and 0. 67%+/-0.16% in Ad hTRP2 (priming)-Ad hTRP2 (boosting) group,28. 50%+/-6.40% and 0.22%+/-0.07% in DC/SVYDFFVWL (priming)-DC/ SVYDFFVWL (boosting) group,and 98. 90%+/-0.90% and 1.05%+/-0.21% in Ad hTRP2 (priming)-DC/ SVYDFFVWI, (boosting) group, respectively. In the tumor-bearing model, none of mice survived in DC/SVYDFFVWL (priming)-DC/SVYDFFVWL (boosting) group, and just only 40% of mice were tumor-free in Ad hTRP2 (priming) -Ad hTRP2 (boosting) group, whereas 100% of mice survived in Ad hTRP2 (priming)-DC/SVYDFFVWL (boosting) group., Conclusion: Boosting with DC/ SVYDFFVWL can significantly enhance the immunity against melanomas elicited by priming with Ad hTRP2, indicating that first priming with Ad hTRP2 and then boosting with DC/SVYDFFVWL is a potentially effective regimen for overcoming the disadvantage that anti-tumor immune response can not be significantly increased by readministration of adenovirus.

Objective: To investigate the effects of dendritic cells (DCs) infected with adenovirus vector encoding xenogeneic alpha-fetoprotein (AFP) on breaking the immune tolerance and induction of immunity against hepatocellular carcinomas., Methods: Human and mouse alpha-fetoprotein full-length cDNA were cloned from human HepG2 and mouse Hepa 1 - 6 hepatoma cell lines, respectively, using RT-PCR, and then inserted into adenoviral shuttle vectors to construct Ad hAFP and Ad mAFP. Mice were immunized with Ad hAFP-infected DC and in vitro CTL activity against Hepa 1 - 6 cells was examined by standard (51)Cr release assay. Survival was studied of the immunized mice, with or without depletion of CD8+ or CD4+ T cells, inoculated with Hepa 1 - 6 mouse hepatoma cells., Results: The lytic activity of CTL elicited by the Ad hAFP-infected DCs were much stronger than that by Ad mAFP-infected DCs. 80% of the Ad hAFP/DCs-immunized mice of the inoculated with 5 x 10(6) Hepa 1 - 6 hepatoma cells were still alive two months after inoculation. However, the Ad mAFP/DCs-immunized mice inoculated with 1 x 10(6) Hepa 1 - 6 cells were just 20% surviving two months later. Depletion of CD8+ or CD4+ T cells abolished such an antigen-specific immunity elicited by the DCs infected with Ad hAFP., Conclusion: Adenovirus vector-mediated xenogeneic AFP-infected DCs can effectively break the immune tolerance to hepatocellular carcinomas in an animal model and induce strong antigen-specific T cell response, which are dependent on CD8+ and CD4+ T cells.

Objective: To analyse related risk factors of classic Kaposi' s sarcoma in Xinjiang., Methods: A 1:4 case-control study was used and the conditional logistic regression model was performed in this study. Cases were followed up in Xinjiang while controls were selected by the same sex, nation and age within 5 years with cases., Results: Interleukin-6,vascular endothelial growth factor, beta-MG, neopterin, human herpevirus 8, were found to be associated with Kaposi's sarcoma risk in one-way variance model while beta2 -MG and human herpevirus 8 entered the multiple conditional logistic regression model, and their ORs were 1.002(95%CI: 1.000-1.003), 81.041 (95%CI: 1.790-3669.620)., Conclusion: There was a correlate relationship between beta2 -MG and classic Kaposi's sarcoma being found that human herpevirus 8 exposure related factors seemed to have played important roles on classic Kaposi's sarcoma in Xinjiang.

Objective: To investigate the relationship between anti-tumor immune response and autoimmunity elicited by adenovirus-mediated xenogeneic melanoma-related antigen tyrosinase-related protein 2 (TRP2)., Methods: Mice divided into three groups were intradermally immunized by dl 70-3 (control group), Ad hTRP2, and Ad hTRP2 respectively. Analysis of the killing activity and production of interferon (IFN) gamma of tumor-specific cytotoxia T lymphocytes (CTL) from the C57BL/6 mice (3 mice per group) immunized with adenoviral vector encoding human or murine TRP2 (Ad hTRP2 or Ad mTRP2) were made using in vivo CTL and intracellular staining of IFN-gamma respectively. Additionally, the survival of mice (10 mice per group) immunized with Ad hTRP2 or Ad mTRP2 was checked after the subcutaneous inoculation with mouse melanoma B16.F10 cells., Results: The CTL lysis activity elicited by Ad hTRP2 was related to the duration of immunization, which increased up to peak one week after the immunization and subsequently decreased. Moreover, the Ad hTRP2-elicited CTL lysis was dose-dependent. The 6 h CTL killing and spleen IFN-gamma-producing CD8(+) T cells in total CD8(+) T cells by one week's immunization with Ad hTRP2 were 94% +/- 5% and 0.87% +/- 0.12%, respectively, whereas the 6 h CTL killing and spleen IFN-gamma-producing CD8(+) T cells by Ad mTRP2 were 22% +/- 8% and 0.15% +/- 0.05% respectively. On the other hand, 80%of the mice inoculated with 1 x 10(6) B16.F10 cells a week after the immunization with Ad hTRP2 were tumor-free for three months, but companied by formation of vitiligo in the Ad injection sites. However, only 20% of the Ad mTRP2-immunized mice inoculated with 1 x 10(5) B16.F10 cells survived, and no vitiligo was formatted., Conclusion: Adenovirus-mediated xenogeneic melanoma-related antigen TRP2 effectively breaks immune tolerance, thus inducing strong antigen-specific cytotoxic T cell response, simultaneously companied by obvious autoimmune injury.

Objective: An human telomerase reverse transcriptase (hTERT) promoter was cloned to investigate the effect of simplex virus-thymidine kinase (HSV-tk) gene-ganciclovir (GCV) system under control of this promoter on lung cancer cells A549., Methods: Specific primers were designed to amplify the core hTERT promoter from HepG2 genome. A set of expression vectors encoding LacZ or tk gene under control of hTERT or hCMV promoter was constructed through standard molecular cloning methods. After the transfection with lipofectamine 2000, reverse transcriptional PCR (RT-PCR) and beta-Gal staining were performed to examine the activity of the hTERT promoter. The cytotoxic effects of GCV/tk on A549 and MRC5 cells transfected with the plasmids encoding tk gene were evaluated by MTT assay., Results: The hTERT promoter containing -208-+40 bp of the upstream sequence of human telomerase was successfully cloned. beta-Gal staining and RT-PCR were used to detect the expression of Lac Z and the transcription of tk gene under control of the hTERT promoter, respectively, in A549 rather than MRC5 cells. Cyototoxic effect of GCV was observed only in the A549 but not MRC5 cells after the transfection with pDC511 hTERT/tk, and the effect was dose-dependent. The effect, however, was observed in cells transfected with pDC518 hCMV/tk., Conclusion: The hTERT promoter cloned in this study can specifically control the target gene expression in telomerase-positive tumor cells but not the normal cells, suggesting that the HSV-tk/GCV system under control of the hTERT promoter is a promising targeted gene therapy for malignant tumors.