Effect of electroacupuncture on small airway function in patients with stable chronic obstructive pulmonary disease / 中国针灸

OBJECTIVE@#To observe the regulatory effect of electroacupuncture (EA) on small airway function and exercise tolerance in patients with stable chronic obstructive pulmonary disease (COPD).@*METHODS@#A total of 62 patients with stable COPD were randomized into an observation group (31 cases, 1 case dropped off) and a control group (31 cases, 5 cases dropped off). On the base of routine medication and aerobic exercise, the patients of the two groups all received EA at Danzhong (CV 17), Rugen (ST 18), Guanyuan (CV 4), Zhongwan (CV 12), Tianshu (ST 25) and Yingchuang (ST 16). In the observation group, filiform needles were used and inserted perpendicularly, 3 mm in depth. In the control group, the placebo needling method was performed, in which the needle was not inserted through skin at each point. In both groups, electric stimulation with low-frequency electronic pulse instrument was exerted, with continuous wave, 2 Hz in frequency, lasting 30 min each time in the two groups. The treatment was given once every other day, 3 times a week, for 14 treatments totally. Before and after treatment, the following indexes were compared in patients between the two groups, i.e. the lung function indexes (forced expiratory volume in first second [FEV1], forced vital capacity [FVC], the ratio of FEV1 to FVC [FEV1/FVC], maximal voluntary ventilation [MVV], the percentage of maximal expiratory flow [MEF] at 25% of FVC exhaled [MEF25], MEF50 and MEF75 in predicted value), cardiopulmonary exercise test indexs (metabolic equivalent [METS], oxygen uptake per kg body weight [VO@*RESULTS@#After treatment, FVC%, MVV%, MEF75%, MEF50%, VO@*CONCLUSION@#Electroacupuncture can improve the respiratory function and exercise tolerance in COPD patients through removing small airway obstruction and increasing ventilation.

Regulatory Mechanism of Electroacupuncture Therapy for Diaphragm Function of Chronic Obstructive Pulmonary Disease Model Rats with Muscular Dystrophy / 广州中医药大学学报

Objective To investigate the effect of electroacupuncture on diaphragm function of chronic obstructive pulmonary disease (COPD) rats with muscular dystrophy, and to explore the regulatory mechanism. Methods Forty male rats were randomly divided into blank group, model group, electroacupuncture group, exercise group, electroacupuncture plus exercise group, 8 rats in each group. After successful establishment of COPD rat model with muscular dystrophy, the modeled rats in various intervention groups were given electroacupuncture and/or exercise treatment. After the last treatment, the changes of rat body mass were observed, the rat lung function was detected, and the mRNA expression levels of myosin heavy chains (MHC) of MHC-1, MHC-2 and diaphragmatic related signal proteins of Atrogin-1, muscle ring-finger protein-1(MuRF-1), MyoD were detected by real-time quantitative polymerase chain reaction (qPCR). Results (1) Compared with the blank group, inspiratory resistance (IR) and functional residual mass (FRC) in the model group were increased (P < 0.05) , and the dynamic lung compliance(Cydn) was decreased(P<0.05). Compared with the model group, IR and FRC in the intervention groups were decreased (P < 0.05), but the differences among the three intervention groups were insignificant(P>0.05). (2) Compared with the blank group, the mRNA expression levels of MHC-1, Atrogin-1, MuRF-1, MyoD in the model group were increased (P<0.05), and the mRNA expression level of MHC-2 was decreased (P < 0.05). Compared with the model group, the mRNA expression levels of MHC-1, Atrogin-1, MuRF-1, MyoD in the intervention groups were decreased (P < 0.05) , and the mRNA expression level of MHC-2 was increased(P<0.05). Compared with the exercise group, the mRNA expression levels of Atrogin-1, MuRF-1, MyoD in the electroacupuncture group were decreased (P<0.05), and the mRNA expression level of MHC-2 was increased (P<0.05) , but the above indexes in electroacupuncture plus exercise group showed no obvious changes(P>0.05). Conclusion Electroacupuncture can improve respiratory function of COPD rats with muscular dystrophy, and the possible mechanism is related with the increase of MHC-2 mRNA expression and with the decrease of Atrogin-1, MuRF-1, MyoD mRNA expression, which result into the regulation of ubiquitin proteasome pathway(UPP), reduction of myosin loss, and the relief of diaphragmatic atrophy.

Differences in the mandibular premolar positions in Angle Class I subjects with different vertical facial types: A cone-beam computed tomography study / 대한치과교정학회지

OBJECTIVE: To compare the positions of the mandibular premolars in Angle Class I subjects according to vertical facial type. The results will provide a theoretical basis for predicting effective tooth movement in orthodontic treatment. METHODS: Cephalometric parameters were determined using cone-beam computed tomography in 120 Angle Class I subjects. Subjects were categorized as short, normal, and long face types according to the Frankfort mandibular angle. Parameters indicating the position of the mandibular right premolars and the mandible were also measured. RESULTS: The angle between the mandibular first premolar axis and buccal cortex, the distance between the root apex and buccal cortex, angle of vestibularization, arc of vestibularization, and root apex maximum movable distance were significantly greater in the short face type than in the long and norm face types. The angle between the mandibular second premolar axis and buccal cortex, the distance from root apex to buccal cortex, and the arc of vestibularization were significantly greater in the short face type than in the normal face type. CONCLUSIONS: There are significant differences in the mandibular premolar positions in Class I subjects according to vertical facial type.

Regulatory effects of acupuncture on exercise tolerance in patients with chronic obstructive pulmonary disease at stable phase: a randomized controlled trial / 中国针灸

<p><b>OBJECTIVE</b>To verify the regulatory effects of acupuncture on exercise tolerance in patients with chronic obstructive pulmonary disease (COPD) at stable phase.</p><p><b>METHODS</b>Thirty cases of COPD were randomly divided into a treatment group (16 cases) and a placebo group (14 cases). Based on specified aerobic exercise, acupuncture was applied in the treatment group and placebo acupuncture was used in the placebo group. The acupoints included Danzhong (CV 17), Rugen (ST 18), Guanyuan (CV 4), Zhongwan (CV 12), Tianshu (ST 25) and so on. The needle did not penetrate into the skin for the placebo group. The treatment was required for 2 to 3 times per week for totally 5 weeks. The indices of exercise tolerance, including 6-min walking distance (6-MWD), exercise time, maximum oxygen uptake (VO2max) forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC), maximum ventilatory volume (MVV), St. George respiratory questionnaire (SGRQ) were observed in two groups before and after treatment.</p><p><b>RESULTS</b>(1) Exercise tolerance: the differences of 6-MWD and exercise time were statistically significant between groups, which were more superior in the treatment group (both P<0.01); the VO2max was significantly increased after treatment in the treatment group (P<0.05), but there was no difference between two groups (P>0.05). (2) Pulmonary ventilation function: the differences of FEV1%, FEV1/FVC and MVV% were statistically significant between groups, which were more superior in the treatment group (P<0.05, P<0.01); (3) SGRQ: the SGRQ was significantly improved after treatment in the treatment group (P<0.05), but there was no difference between two groups (P>0.05).</p><p><b>CONCLUSION</b>The acupuncture could improve the exercise tolerance in patients with chronic obstructive pulmonary disease at stable phase, and shorten the onset time of aerobic exercise. Besides, acupuncture combined with aerobic exercise could effectively improve the pulmonary function.</p>

The entry of Epstein-Barr virus into B lymphocytes and epithelial cells during infection / 病毒学报

Epstein-Barr virus (EBV) is a human herpesvirus associated with important human diseases, including infectious mononucleosis syndrome, malignant lymphoma, and nasopharyngeal carcinoma. The mechanism of EBV entry into host cells remains a subject of intensive research. After decades of study, researchers have identified several key proteins and different patterns of EBV intrusion into host cells. The viral surface glycoproteins, gp350/220, gp42, gB, gH, and gL, are involved in interactions with the CR2 receptor on the surface of B lymphocytes during viral entry. However, the majority of epithelial cells lack CR2 receptor expression, which makes viral invasion much more complex than in B lymphocytes. Three different models have been proposed to explain how EBV enters epithelial cells: (1) "transfer of infection", mediated by B lymphocytes or Langerhans cells; (2) EBV utilizes its own proteins during the process of fusion with the cell membrane; and (3) progeny virions arising from EBV-infected epithelial cells cross lateral membranes into adjacent epithelial cells. This review will discuss the relevant mechanism of viral entry into B lymphocytes and epithelial cells during EBV infection.

Effects of clotrimazole on the growth of oral squamous cell carcinoma / 中华口腔医学杂志

<p><b>OBJECTIVE</b>to investigate the effects of clotrimazole on the growth of oral squamous cell carcinoma (OSCC).</p><p><b>METHODS</b>OSCC-25 cells growing in log phase were treated with various doses of clotrimazole. The concentration of IC(50), cell cycle and cell cycle related protein were examined.</p><p><b>RESULTS</b>the concentration of clotrimazole for inhibiting OSCC was IC(50) 8.51 µmol/L. Clotrimazole induced cell cycle arrest in the G(0)-G(1) cell cycle phase, with a concomitant decrease of cells in the G(2)-M and S-phase. Furthermore, clotrimazole significantly decreased the levels of cyclin D, cyclin E and CDK-4.</p><p><b>CONCLUSIONS</b>clotrimazole inhibits the growth of OSCC.</p>

Alteration of gene expression during nasopharyngeal carcinogenesis revealed by oligonucleotide microarray after microdissection of tumor tissue and normal epithelia from nasopharynx / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Microarray and microdissection techniques were being used for many applications to study the carcinogenesis of some human tumors. But seldom studies had hitherto combined these two techniques to study carcinogenesis mechanism of nasopharyngeal carcinoma (NPC). To identify a set of genes involved in the carcinogenesis and development of NPC, we used the microdissected homogeneous NPC tissue cells and the pure normal epithelium pillar cells to construct the whole human genome expression profiles.</p><p><b>METHODS</b>We preserved the tissue samples from nasopharynx of 18 patients (including 13 samples of NPC and 5 samples of normal or inflammatory mucous tissue samples from nasopharynx) in RNAlater Stabilization Reagent. The tissue samples were microdissected to harvest the homogeneous tissue cells, then total RNA was isolated from them. The sufficient antisense RNA (aRNA) was amplified from these total RNA. HG-U133.Plus.2.0 GeneChip was used to construct the human whole genome expression profiling of each sample. Differential patterns of expression of genes correlated with the carcinogenesis, classification and progression of NPC were identified with comparing the expression profiling data respectively in leave one out cross-validation analysis. Correlation between aRNA expression measured by the microarrays and semi-quantitative reverse transcription polymerase chain reaction (sqRT-PCR) were also ascertained, and found that hybridization results were validated in all of the 18 patients.</p><p><b>RESULTS</b>Differential patterns of expression of 127 genes correlated with the carcinogenesis (A P value less than 0.001 with the 2-fold differentiated expression between case group and control group) of the NPC were filtered. The top most up-regulated and down-regulated 8 genes by the way of permutation test were also selected and listed in the paper. Expression of genes E2F6 and TSPAN-1 was identified using aRNA by sqRT-PCR and showed that there was significant difference between the average value of case groups and that of control group respectively (t = 2.170, df = 16, P = 0.045 and t = -2.946, df = 16, P = 0.009).</p><p><b>CONCLUSIONS</b>We had identified some genes which could be the molecular marker during the carcinogenesis and the development of the NPC. The genes which selected from the different subgroups seemed to be implicated for the diagnosis,classification, and progression of NPC, and provided important insights into their underlying biology.</p>

Construction and screening of genomic library from Raji cells / 中南大学学报(医学版)

OBJECTIVE@#To construct the genomic library of Raji cells and screen it by EBV DNA probe.@*METHODS@#High molecular weight genomic DNA of Raji cells was digested by restriction enzyme BamHI. DNA fragments ranging from 9 to 23 kb were recovered by agarose gel electrophoresis, which were ligated with Lambda DASH II vector BamHI arms pre-treated with calf intestine alkaline phosphatase (CIAP). Ligated DNA was packed in vitro using Gigapack III gold packaging extract. The library was plated on XL1-blue MRA (P2) host strain.Titering and screening of the Raji genomic library were performed.@*RESULTS@#The primary titer of the Raji genomic library was 1.8 x 10(5) pfu/mL, while that of the amplified library was 2.8 x 10(8) pfu/mL. Plaques (1 x 10(5)) were screened with (32)P-labeled EBV DNA probe(EBV genome 5-3271), 4 positive clones were obtained, and 1 of the 4 positive clones was picked out randomly for the second round of plaque screening. All the phage plaques were positive. DNA of the positive clone was extracted and was digested with BamHI. The length of the inserted fragment was 8.5 kb. Sequencing and BLAST analysis revealed that the inserted fragments consisted of the BamHI-W fragment at one end and clone RP11-665A22 on chromosome 15 at the other end.@*CONCLUSION@#The successfully established genomic library of Raji cells will provide a basis for cloning the sequences of the EBV junction sites and interpreting the mechanism of oncogenesis of EBV integration.

Functional genomics of nasopharyngeal carcinoma susceptibility/suppressor gene / 中南大学学报(医学版)

There is obvious allele disequilibrium in nasopharyngeal carcinoma at chromosome 3p, 9p, 6q, 11q, 13q and 14q. Nasopharyngeal carcinoma (NPC) susceptibility/suppressor gene candidates were obtained by molecular biology methods,such as cDNA representational difference ana-lysis. The functional research of NPC susceptibility/ suppressor gene candidates indicated: (1) The increased expression of Cx contributed to obstacles of gap junctional intercellular communication (GJIC), and resulted an aberration of GJIC; (2) BRD7, a transcript factor, was associated with cell cycle regulation; (3) NAG7,an estrogen receptor repressor, inhibited the invasive potential of human NPC cells by regulating ERalpha expression and the H-ras/p-c-Raf and JNK/AP-1/MMP1 signaling pathways; (4) NGX6, a metastasis-associated protein, can negative-regulate EGF/Ras/MAPK signaling transduction pathway, and interact with ezrin protein to inhibit invasion and metastasis of NPC cells; (5) SPLUNC1, a secreted protein, can inhibit the bacterium clone formation, and is an innate immune molecule. These data will lay an important foundation for the NPC mechanism.

Effect of all-trans-retinoic acid on C6 glioma cell proliferation and differentiation / 中南大学学报(医学版)

OBJECTIVE@#To explore the effect of all-trans-retinoic acid (ATRA) on the growth inhibition and cellular differentiation of C6 glioma cells.@*METHODS@#Human glioma C6 cells were treated with 5 mg/L ATRA,and the inhibition of cell growth was assessed by methyl thiazolyl tetrazolium assay. The differentiation of C6 cells was determined by flow cytometry, microscopy,transmission electron microscope, and immunohistochemical technique.@*RESULTS@#Treatment of ATRA could result in the growth inhibition of C6 cells, and the cell density significantly decreased(P0.05).Whereas, early apoptosis was observed under the transmission electron microscope, the vacuoles increased, the mitochondria and endoplasmic reticulum were abundant in the cytoplasm, and the cellular structures tended to be normal.The expression of glial fibrillaryacidic protein in C6 cells increased in the treatment group.@*CONCLUSION@#ATRA can inhibit the proliferation, and induce the differentiation of C6 glioma cells.

Omics docking for polygenic inheritance tumors / 中南大学学报(医学版)

Omics docking study for polygenic inheritance tumors has become an important strategy in oncology research. This review focuses on the conceptions and technologies of omics, and puts forward the central contents and omics docking for polygenic inheritance tumor to reveal the role of molecular changes at different stages of polygenic inheritance tumor at multidisciplinary and multilayer level. It is a new strategy to explore the mechanism of tumor carcinogenesis, and to regulate the network, key molecules, and drug target by combined biology effects.

Metabolomics and its application in malignant tumors / 中南大学学报(医学版)

Metabolomics is a new science and technology, which it refers to a holistic analytical approach to all the low molecular weight metabolites in an organism or a cell. In this paper, the definition and objective of metabolomics are provided, and the current application of metabolomic research in malignant tumors (diagnosis and therapy) are summarized.

Blockage of U251 cells in G0/G1 through MAPK signaling pathway by LRRC4 / 中南大学学报(医学版)

OBJECTIVE@#To explore the effect of LRRC4, a glioma suppressive gene, on blocking U251 cells in G0/G1 by MAPK signaling pathway.@*METHODS@#LRRC4 was transfected into U251 cells, and at 24 hour of post-transfection, cells were split at a 1:3 dilution, challenged with 500 microg /mL G418 and formed a stable transfected clone pool. RT-PCR, Northern blot and Western blot were used to identify the stable transfectants. ERK, JNK and P38 expression changes were analyzed by Western blot. FACS analysis, Luciferase reporter gene assay and Western blot were used to detect the cell cycle and cyclin D1.@*RESULTS@#LRRC4 down-regulated the expression of phosphorylated ERK2 and up-regulated the expression of total protein JNK2 (a key molecule of MAPK signaling pathway) and phosphorylated c-Jun. LRRC4 decreased the expression of mutation P53, cyclin D1 activation and its expression. U251 cells were blocked in G0/G1 by LRRC4.@*CONCLUSION@#LRRC4 can decrease JNK2, up-regulate the phosphoralated c-Jun, down-regulate mutant P53 and cyclin D1, and therefore block U251 cells in G0/G1.

Expression absence of LRRC4 gene in glioblastoma cell lines / 中南大学学报(医学版)

OBJECTIVE@#To examine the expression absence of LRRC4 gene in glioblastoma cell lines.@*METHODS@#RT-PCR and Northern blot were used to detect the expression of LRRC4 gene in 6 glioblastomas cells lines. Polymerase chain reaction and DNA sequencing were used to screen the LRRC4 gene mutation, while bioinformation assay was used to search for the reason of LRRC4 gene absence in U251 cell lines.@*RESULTS@#The expression of LRRC4 was absent in 6 malignant glioma cell lines (U251, U87, BT325, SF126, SF767 and M17), which were examined by Northern-blot and RT-PCR assay. All sequencing of PCR products from gDNA of SF126, SF767, and M17 cell lines contained the point mutation at the same position ( LRRC4 geneT977A) (3/5), which was a synonymous mutation. However, PCR products from gDNA of U251 and U87 cell lines (2/5) were not obtained. The expression absence of LRRC4 was ascribed to the loss of homozygosity of 7q32-ter in U251 cell lines.@*CONCLUSION@#The expression of LRRC4 gene is absent in glioblastoma cell lines, and it offers the important experiment proof for LRRC4 to act as a new candidate of brain tumor suppressor gene from glioma. The loss of homozygosity of 7q32-ter contributed to the expression absence of LRRC4 in U251 cell lines.

Preparation of anti-LRRC4 polyclonal antibody and its application in constructing expression profile of human gliomas with different pathological grades / 中南大学学报(医学版)

OBJECTIVE@#To prepare anti-LRRC4 polyclonal antibody and analyze the correlation between the expression of LRRC4 and pathological grades of gliomas in rabbits.@*METHODS@#Appropriate protein sequence with good hydrophilicity and antigenicity was chosen by analyzing with DS Gene 1.1 software. The corresponding nucleic acid sequence amplified by PCR was used to construct a recombinant pGEX-4T-2/276 bp. E.coli JM109 transformed with the recombinant was induced by IPTG to express GST-fusion protein, and the fusion protein expressed as insoluble inclusion bodies. Then the purified inclusion body was used to immunize rabbits. Once the titer of antiserum reached 1:10(8) by indirect ELISA, the serum was collected and purified. The expression-profile of LRRC4 in embryonic tissues and gliomas with various pathological grades were obtained by western blot and immunohistochemistry with the anti-LRRC4 polyclonal antibody.@*RESULTS@#The highly specific anti-LRRC4 polyclonal antibody whose titer reached 1:10(8) was prepared. The relatively specific expression of LRRC4 was detected in the normal brain, but reduced expression or loss of expression in gliomas was also noticed by immunohistochemistry, and there was a correlation between the expression level of lrrc4 and the pathological grade of gliomas.@*CONCLUSION@#The anti-LRRC4 polyclonal antibody with high titer and specificity has been obtained. A correlation between the expression level of LRRC4 and the pathological grade of gliomas is detected, which lays the foundation for advanced research of LRRC4.

Inhibitory effect of LRRC4 on the mobility and invasion of glioblastomas through the SDF-1alpha/CXCR4 axis / 中南大学学报(医学版)

OBJECTIVE@#To explore the effect of LRRC4 on the mobility and invasion of glioblastomas U251 cells through the SDF-1alpha/CXCR4 axis.@*METHODS@#RT-PCR, transfilter cell invasion assay, adhesion assay, scraping test, scrape loading, and dye transfer assay were used to determine the effect of LRRC4 on U251 cells.@*RESULTS@#SDF-1 alpha could increase the invasion in U251 which expressed CXCR4. The reintroduction of LRRC4 in U251 cells could inhibit the expression of CXCR4. LRRC4 also inhibited the adhesion ability of U251 to ECV304 as well as the mobility and invasion ability in vitro, which was mediated by the SDF-1alpha/CXCR4 axis. Furthermore, LRRC4 could greatly enhance the gap junctional intercellular communication of U251 cells.@*CONCLUSION@#The reintroduction of LRRC4 in U251 cells can inhibit the expression of CXCR4 and the SDF-1alpha/CXCR4 axis-mediated cell invasion in vitro.

Protective effect of amlodipine on the cytotoxicity induced by contrast media in human kidney cells / 中南大学学报(医学版)

OBJECTIVE@#To explore the protective effect of amlodipine on the cytotoxicity induced by contrast media (meglumine diatrizoate) in human kidney cells (HKC).@*METHODS@#An HKC line was used. The experiment was divided into 4 groups: a model group (diatrizoate 111g/L), a prevention group (diatrizoate 111g/L+amlodipine 10(-5)mol/L), an amlodipine control group (amlodipine 10(-5)mol/L), and a culture medium control group (simple none blood serum DMEM-F12 medium). Cytotoxicity induced by meglumine diatrizoate was analysed by methyl thiazolyl tetrazolium (MTT) test, lactate dehydrogenase (LDH) assay, Hochest33258 fluorescence stained cytospins, and flow cytometric DNA analysis. The protein expression of Bax was determined by Western blot, and caspase-3 activity was examined by fluorometric method.@*RESULTS@#In the prevention group, the cell viability increased significantly (P<0.05), LDH levels decreased (P<0.05), and the apoptosis was lower than that of the model group (P<0.05) .Bax protein expression and caspase 3 activity decreased (P<0.05).@*CONCLUSION@#Amlodipine can inhibit the HKC apoptosis and protect the renal tubule cell from injury induced by meglumine diatrizoate.

Progression of lipopolysaccharide signal pathway / 中南大学学报(医学版)

Lipopolysaccharide (LPS) is the major constituents of the outer membrane of Gram-negative bacteria. LPS recognition and signal transmission are key events in the host defense reaction towards Gram-negative bacteria and are associated with many disorders. Multiple signaling pathways are involved in the response to LPS. With the help of LPS-binding protein and CD14, TLR4 binds with LPS, then recruits myeloid differentiation factor 88 and IL-1 receptor-associated kinase, and further phosphorylates and activates TNF receptor associated factor 6 (TRAF6). The activated TRAF6 leads to the activation of transcription factor NF-kappaB and MAP kinase's pathways that involves in LPS-induced cellular responses and the production of proinflammatory cytokines such as TNF-alpha, IL-6 and IL8.

Effect of growth inhibition of the secretory protein SPLUNC1 on Pseudomonas aeruginosa / 中南大学学报(医学版)

OBJECTIVE@#To express the recombinant SPLUNC1 protein in HNE1 cells and to study its function of bactericidal and binding to lipopolysaccharide (LPS).@*METHODS@#Full length of SPLUNC1 gene was cloned into pCMV-tag4A vector and stably transfected into HNE1 cell lines, the supernatant of cell cultures was collected. After being treated with the supernatant, the Pseudomonas aeruginosa was seeded to LB soft agar plate, and the bacteria clones were counted and analyzed. For in vitro LPS binding assay, LPS was coated to 96-well plates. We incubated in the plate with SPLUNC1 protein, and detected the binded SPLUNC1 protein by ELISA. Incubating the FITC-LPS with the SPLUNC1 stably transfected or control cells, the intracellular intensity of fluorescence was observed under the fluorescence microscope.@*RESULTS@#SPLUNC1 inhibited the bacteria clone formation obviously. Although the binding efficiency of LPS and SPLUNC1 in vitro was very low, more FITC-LPS entered into the SPLUNC1 stably transfected cells.@*CONCLUSION@#SPLUNC1 can inhibit the growth of Pseudomonas aeruginosa and bind LPS, and play an important defensive role in innate immunity of the upper airway.

Infectious Cloning Approach for Herpesvirus Based on Bacterial Artificial Chromosomes / 中国生物工程杂志

The genetic analysis of herpesviruses has been a constant challenge, due to the large, complex genomes of herpesviruses and mutagenesis of viral genes by conventional recombination methods in cell culture. Recently, a completely new approach for full-length infectious clones of herpesviruses based on bacterial artificial chromosomes (BACs) has been developed. This technique allows the maintenance, propagation and genetic modification of the viral genome as a BAC plasmid in E.coli, thus making the procedures fast, safe and effective in prokaryotic cells. This technique also makes it possible for the reconstitution of viral progeny or mutants by transfection of the BAC plasmid into eukaryotic cells, thereby facilitating the analysis of viral gene functions in the context of genome. In this presentation, Epstein-Barr virus was used as an example to describe the principle, establishment of the technique and mutation introduction into the BAC plasmid, and to discuss the perspective in the use of BAC-cloned herpesviruses.