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Lü-Sheng Si

Publications and source records attributed to Lü-Sheng Si.

9 recordsLinked to original sources
PubMed2006

Predicting the nuclear localization signals of 107 types of HPV L1 proteins by bioinformatic analysis.

In this study, 107 types of human papillomavirus (HPV) L1 protein sequences were obtained from available databases, and the nuclear localization signals (NLSs) of these HPV L1 proteins were analyzed and predicted by bioinformatic analysis. Out of the 107 types, the NLSs of 39 types were predicted by PredictNLS software (35 types of bipartite NLSs and 4 types of monopartite NLSs). The NLSs of the remaining HPV types were predicted according to the characteristics and the homology of the already predicted NLSs as well as the general rule of NLSs. According to the result, the NLSs of 107 types of HPV L1 proteins were classified into 15 categories. The different types of HPV L1 proteins in the same NLS category could share the similar or the same nucleocytoplasmic transport pathway. They might be used as the same target to prevent and treat different types of HPV infection. The results also showed that bioinformatic technology could be used to analyze and predict NLSs of proteins.

Amino Acid Sequence↗
PubMed2006

[In situ analysis of distribution of immunocompetent cells in tumor's local draining lymph nodes].

AIM: To observe the distribution of immunocompetent cells (ICCs) in tumor's local draining lymph nodes (LDLN) at different stages of disease including non-metastasis, micro-metastasis and late metastasis. METHODS: 71 LDLN from 22 breast cancer, 28 LDLN from 7 gastric carcinoma were analysed by using catalyzed signal amplification (CSA) immunohistochemical staining. Monoclonal antibodies (mAbs) to perforin, granzyme B, CD8, CD56, CD68, S-100, CD134 and CD25 were used to detect the amount and functional change of ICCs. RESULTS: Paracortical hyperplasia and sinus histocytosis was mainly observed in tumor's LDLN. As it was reported, the density of S100(+) dendritic cells (DCs) was decreased as the draining lymph nodes became tumor-containing from the status of tumor free (P<0.05), and the morphology of DCs turned to be inactivated. As the lymph nodes were invaded by tumors, the densities of CD134(+) lymphocytes and CD25(+) cells were significantly increased (P<0.01). Furthermore, there was a significant trend of decreasing in the number of activated cytotoxic T lymphocytes (granzyme B(+) cells) in LDLN as tumor progressed from non/micro-metastasis, early metastasis to advanced stage metastasis (P<0.01). There was no obvious difference in distribution of ICC between non/micro-metastasis sentinel lymph nodes and non-sentinel lymph nodes. CONCLUSION: The dynamic change of the ICCs in LDLN implied that immune response of tumor bearing host tends to be inhibited with the progress of tumors.

Cell Count↗
PubMed2005

Construction of prophylactic human papillomavirus type 16 L1 capsid protein vaccine delivered by live attenuated Shigella flexneri strain sh42.

To express human papillomavirus (HPV) L1 capsid protein in the recombinant strain of Shigella and study the potential of a live attenuated Shigella-based HPV prophylactic vaccine in preventing HPV infection, the icsA/virG fragment of Shigella-based prokaryotic expression plasmid pHS3199 was constructed. HPV type 16 L1 (HPV16L1) gene was inserted into plasmid pHS3199 to form the pHS3199-HPV16L1 construct, and pHS3199-HPV16L1 was electroporated into a live attenuated Shigella strain sh42. Western blotting analysis showed that HPV16L1 could be expressed stably in the recombinant strain sh42-HPV16L1. Sereny test results were negative, which showed that the sh42-HPV16L1 lost virulence. However, the attenuated recombinant strain partially maintained the invasive property as indicated by the HeLa cell infection assay. Specific IgG, IgA antibody against HPV16L1 virus-like particles (VLPs) were detected in the sera, intestinal lavage and vaginal lavage from animals immunized by sh42-HPV16L1. The number of antibody-secreting cells in the spleen and draining lymph nodes were increased significantly compared with the control group. Sera from immunized animals inhibited murine hemagglutination induced by HPV16L1 VLPs, which indicated that the candidate vaccine could stimulate an efficient immune response in guinea pig's mucosal sites. This may be an effective strategy for the development of an HPV prophylactic oral vaccine.

Animals↗
PubMed2005

Expression of human papillomavirus type 16 L1 protein in transgenic tobacco plants.

To develop a plant expression system for the production of the human papillomavirus type 16 (HPV16) vaccine, we investigated whether the HPV16 L1 protein can be expressed in tobacco plants and whether it can be used as the cheapest form of edible vaccine. The HPV16 L1 coding sequence was amplified by PCR using specific primers from the plasmid pGEM-T-HPV16 containing the template sequence, and subcloned into the intermediate vector pUCmT and binary vector pBI121 consecutively to obtain the plant expression plasmid pBI-L1. The T-DNA regions of the pBI-L1 binary vector contained the constitutive Cauliflower mosaic virus (CaMV) 35S promoter and the neomycin phosphotransferase npt II gene, which allowed the selection of transformed plants using kanamycin. The tobacco plants were transformed by co-cultivating them, using the leaf disc method, with Agrobacterium tumefaciens LBA4404, which harbored the plant expression plasmid. The regenerated transgenic tobacco plants were selected using kanamycin, and confirmed by PCR. The results of the Southern blot assay also showed that the HPV16 L1 gene was integrated stably into the genome of the transformed tobacco plants. The Western blot analysis showed that the transformed tobacco leaves could express the HPV16 L1 protein. Furthermore, it was demonstrated by ELISA assay that the expressed protein accounted for 0.034%-0.076% of the total soluble leaf protein, was able to form 55 nm virus-like particles compatible with HPV virus-like particle (VLP), and induced mouse erythrocyte hemagglutination in vitro. The present results indicate that the HPV16 L1 protein can be expressed in transgenic tobacco plants and the expressed protein possesses the natural features of the HPV16 L1 protein, implying that the HPV16 L1 transgenic plants can be potentially used as an edible vaccine.

Agrobacterium tumefaciens↗
PubMed2005

[Mechanism of apoptosis induced by indole-3-acetic acids combined with horseradish peroxidase in leukemia cell line K562].

To investigate the possible mechanism of apoptosis induced by indole-3-acetic acid (IAA) combined with horseradish peroxidase in leukemia cell line K562, cell proliferation and apoptosis of K562 cell were examined by MTT assay and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL), respectively; the activity of superoxide dismutase (SOD) and the quantitative change of MDA were measured by biochemical method; changes of free radical were determined by 2, 7-dichlorofluorescin diacetate (DCFH-DA) probe with confocal microscopy. The results showed that of MTT assay and TUNEL indicated that IAA/HRP could significantly inhibit cell proliferation (P < 0.05) and induce apoptosis of K562 cell (P < 0.01), at the same time a positive correlation was found between apoptosis rate and IAA concentration (r = 0.971, P < 0.01). The activity of SOD and the quantitative of MDA increased, accompanied with a rise in IAA concentration. Results detected by DCFH-DA probe indicated that the fluorescence intensity of intracellular free radical increased, as compared with control, and a positive correlation was found. It is concluded that IAA/HRP can inhibit proliferation of K562 cells and induce K562 cell apoptosis, its mechanism may be related with the increase of intracellular free radical due to the effects of IAA/HRP.

Apoptosis↗
PubMed2004

[Carboxyl terminus truncated HPV58 virus L1 protein expressed with baculovirus system and its bioactivity].

To prepare carboxyl terminus truncated human papillomavirus type 58L1 protein, and study on its in vitro bioactivity. PCR was used to amplify carboxyl terminus truncated HPV 58L1 gene, the product was inserted into the PUCMT cloning vector, preparing recombinant PFastBacHTb containing carboxyl terminus truncated HPV58L1 gene. Further more, the recombinant plasmid PfastbacHTb was used to transform DH10Bac cells, constructing recombinant Baculovirus, then the recombinant virus was successfully used to infect Sf-9 insect cells. After incubating at 27 degrees C for 72 hours, the infected cells were collected and total cellular proteins were extracted. The target protein with MW 58KD was revealed by SDS-PAGE and confirmed by Western blot. The interested protein was purified by ProBond purification system. The purified interested protein was identified to self-assemble into VLPs by Transmission electron microscope, and induce murine erythrocyte hemagglutination, indicating that the given proteins had the conformation of VLPs, collecting, HPV58L1 proteins with carboxyl terminus truncation could be efficiently expressed in baculovirus Sf-9 cells expression system, it has identical in vitro bioactivity to the wild type HPV58L1, The present study is fundmental for preparing HPV58L1 prophylactic vaccine.

Animals↗
PubMed2003

Analysis of the immunological microenvironment at the tumor site in patients with non-small cell lung cancer.

BACKGROUND AND AIMS: Inactivation of tumor-infiltrating lymphocytes by immunomodulating cytokines shed by tumor cells into the tumor local microenvironment might be a potential escape strategy of various tumors from immune-immediate killing. Here, we provide an analysis of the cytokine profile at the tumor site in patients with non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: Using in situ hybridization (ISH), we determined the mRNA expression in lymphocytes and tumor cells for IL-2, INF-gamma, IL-12 (p40), IL-18, IL-4, IL-10, TGF-beta1, IL-1, IL-3, IL-8, granulocyte-macrophage colony-stimulating factor (GM-CSF), TNF-alpha, and TGF-alpha in five fresh pleural effusion samples and 18 tumor tissue samples of patients with NSCLC. RESULTS: In pleural effusion as well as in tumor tissue of NSCLC patients, the mRNA expression of IL-4, IL-10, TGF-alpha, and TGF-beta1 was significantly higher than that of IL-2, IL-12, IL-18 and INF-gamma. In contrast, the analysis of tuberculosis pleural effusion samples revealed lower mRNA levels for all cytokines and did not show any significant difference among them. CONCLUSION: The predominant mRNA expression of type II and immunosuppressive cytokines in pleural effusion and tumor tissue of NSCLC patients mirrors an immunosuppressive state in the immunological microenvironment. The present study may, therefore, help to elucidate mechanisms of tumor escape and contribute to the development of an effective immunomodulatory treatment of NSCLC.

Carcinoma, Non-Small-Cell Lung↗
PubMed2001

Expression of Human Single Chain Interleukin 12 Gene in Drosophila Cells.

The hscIL-12 gene(no signal sequence), amplified by PCR, was subcloned into an expressing vector pMT/Bip/V5. The recombinant plasmid was transferedinto Drosophila cell line S2. The secreted hscIL-12 fusion protein was identified by Western blot, and the bioactivity of hscIL-12 was investigated by lymphocyte proliferation assay. The results showed hscIL-12 expressed in S2 cells could stimulate lymphocyte proliferation in dose-dependent manner. hscIL-12 has bioactivity identical to natural interleukin 12. These findings suggest that hscIL-12 is promising in theoretical reseach and in clinical use.

Journal Article↗