Antigen Gene Cloning and Expression of HIV-1 for AIDS Vaccine Design Ⅲ. HIV-1 Antigen Gene Cloning, in Vitro Expression and Antibody Induction

Objective: To evaluate the humoral immune induction in rats of a candidate AIDS vaccine expressing the gag p24 gene froma subtype B HIV-1 isolate. Methods: The amplified p24 gene was inserted into aneukaryotic expression vector to form the supercoiled DNAvaccine. The linearized expressed DNA vaccine was preparedfrom the expression plasmid by polymerase chain reaction(PCR). The antigen gene expression in rats of the linearizedand supercoiled DNA vaccines were in vitro and in vivodetected. Results: In vitro transcription and Northern hybridizationshowed that the linearized DNA vaccine could synthesizeamounts or p24 mRNA similar to the supercoiled DNA vaccine.Antibody assays of inoculated rats confirmed that thelinearized expression DNA could induce a slightly higherantibody titer than the expression plasmid, while the highestautibody titer had been induced by plasmid plus adjuvantinoculation. Conclusion: The construction of a candidate AIDS vaccinebased on the p24 gene could shed light on a potential IV vaccine, meriting evaluation in a rhesus macaque SHIV-AIDSmodel.

Antigen Gene Cloning and Expression of HIV-1 Toward an AIDS Vaccine Design Ⅰ.Amplification and Sequencing of HIV-1 Antigen Genes

Objective:To amplify antigen genes from patients with human immunodeficiency virus type 1 (HIV-1) in Guangdong Province for candidate AIDS vaccine design. Methods:Viral nucleic acid was isolated from 10 HIV-1 infected individuals' peripheral blood collected during 1995-2000 in Guangdong Province. The viral gag p24 gene and env gp120 gene were amplified by nested-PCR and sequenced. The homologies among HIV-1 isolates were compared with HIV-BLAST. Results: Among 10 HIV-1 isolates, nine are homologous to viruses of subtype B, and one is homologous to viruses of subtype E. Conclusion: Subtype B viruses of HIV-1 are predominantly present in Guangdong Province.

Anti-tumor effects induced by gene vaccines co-expressing truncated human prostate specific membrane antigen gene and mouse 4-1BBL

Objective To investigate the influence of m4-1BBL on anti-tumor effects induced by truncated human prostate specific membrane antigen ( tPSMA ) gene in mice. Methods A eukaryotic expression plasmid encoding tPSMA and m4-1BBL ( pDC316-tPSMA-IRES m4-1BBL) ,pDC316-tPSMA and pDC316 were constructed.

Immunogenicity of recombinant attenuated Salmonella typhimurium expressing a 45-peptide hybrid antigen gene of Plasmodium falciparum

A synthetic hybrid 45-peptide gene of Plasmodium falciparum (Pf), which encoded two CSP repeated peptides NANP and three merozoite peptides SPf83. 1, SPf55. 1 and SPf35. 1, was cloned in an expression vector pWR450-1, then the recombinant plasmid pWRA was introduced into the attenuated Salmonella typhimurium SL3261. When used as a live vaccine and administered orally (po), intravenously (iv) or intraperitoneally (ip),the recombinant strain was able to live in vivo and elicit specific humoral and cellular immunity in BALB/c mice and rabbits. As oral immunization is safe and effective, it is thought that the live recombinant Salmonella tyPhimurium vaccine may bring the Pf oral live vaccine a step nearer.

Cloning and characterization of proliferating cell nuclear antigen gene of Alexandrium catenella (Dinoflagellate) with respect to cell growth

Harmful algal blooms （HABs） have been affecting negatively the shellfish and aquaculture industries around the world. Though a lot of efforts have been made to disclose the changes of environmental factors involved and their effects on the HABs events, the molecular mechanism of this process remains unclear. To address this problem, proliferating cell nuclear antigen gene （pcna） was isolated and characterized from Alexandrium catenella. It showed high homology to those of other dinoflagellates （89% and 91% homology to Pfiesteria piscicid and Pyrocystis lunula, respectively）, and also 42%–43% homology to those of plant and animals. The expression level of pcna revealed by quantitative real time PCR was the lowest at the late lagging cell growth phase, increased to the highest at the late exponential phase, and then decreased at the stationary phase. Though the cell growth rate was also changing, no positive correlation between pcna expression level and cell growth rate was displayed throughout the whole cell growth stages （r 2 =0.024 6）. However, the pcna expression level had the similar trend with the change of cell growth rate throughout the whole growing process, e.g., from increasing at the earlier cell growth stage to decreasing at the following stages, though slightly lagging to the latter.

Construction of the Antisense Eukaryotic Vector for Proliferating Cell Nuclear Antigen Gene and Its Expression in Bladder Cancer EJ Cell Line

To explore a novel strategy for antisense gene therapy of cancer,the coding sequence of hum an proliferating cell nuclear antigen(PCNA) c DNA was reversely inserted into the eukaryotic vector p L XSN by molecular cloning techniques and transferred into bladder cancer EJcells with li- posome. The PCNA expression in transferred cells was dynamically detected by immunofluo- rescence and RT- PCR techniques. Changes of proliferation activities of cancer cells were assayed by MTT colorim etric and cloning formation m ethods.In the experiment,the antisense eukaryotic vector was successfully constructed and nam ed as p L APSN.After transfection with it for1- 7 days,PCNA protein and m RNA levels in cancer cells were blocked by16 .74 % - 84 .2 1% (P< 0 .0 5 ) and2 3.2 7% - 86 .15 % (P<0 .0 5 ) respectively.The proliferation activities of transferred cells were inhibited by 2 7.91% - 6 2 .0 7% (P<0 .0 1) ,with cloning formation abilities being de- creased by 5 0 .81% (P<0 .0 1) . Itwas concluded that the in vitro proliferation activities of cancer cells could be effectively inhibited by blocking PCNA expression with antisense technique,which could serve as an ideal strategy for gene therapy of bladder cancer.

Association of Haplotypes in Exon 4 of KLK2 Gene with Raised Serum Prostate-Specific Antigen

The standard diagnostic modalities for Prostate Cancer (PC) include serum Prostate-Specific Antigen (PSA) assay, Digital Rectal Examination (DRE), and histological examination of prostate biopsy. They are limited by low predictive potential and inability to predict which patients are at risk of developing metastatic disease. The aim of this study is to investigate the exon 4 of the KLK2 gene of subjects for changes in its nucleotide sequences (SNPs) and determine the correlation of these changes with serum PSA in an Igbo population of Nigeria. One hundred male subjects aged 40 years and above, who gave their consent, were used for the study. Their PSA determinations were done using ELISA technique while genetic studies were carried out using real-time PCR. tPSA, fPSA, and % fPSA of the subjects ranged between 0.8% - 18.30%, 0.10% - 1.60% and 0.0% - 0.7% respectively. Of the 100 subjects, 28 subjects had tPSA levels above 4.0 ng/ml with a mean of 7.10 (±3.30) ng/ml. Those with tPSA less than 4 ng/ml had a mean of 1.87 (±0.85) ng/m. 15 subjects showed SNPs with a mean tPSA of 6.87 (±4.82) ng/ml while the remaining 85 subjects without SNPs had a mean of 1.86 (±0.80) ng/ml. Results from direct DNA sequencing showed 11 SNPs. Ten subjects are curated in SNP database while one is uncurated. The Chi-square test showed significant association (p = 0.00) between tPSA levels and SNPs mutation (X2 = 17.35, p = 0.00). A Kruskal-Wallis test demonstrated that the positional arrangement of the SNP mutations had no effect on PSA-total or free-values (H (10) = 10.92, p = 0.28;H (10) = 10.07, p = 0.38 respectively). Two SNPs: rs6072 and rs74478031 were associated with elevated PSA levels (p < 0.05). Their presence, therefore, has the potential to serve, in conjunction with raised PSA, as biomarkers of prostate cancer in the study population.

Expression and significance of HBV genes and their antigens in human primary intrahepatic cholangiocarcinoma

AIM To explore the etiology and pathogenesis of human primary intrahepatic cholangiocarcinoma, the expression of HBV genes and HBV-antigens was detected in the cancerous tissue and its surrounding hepatic tissues.METHODS HBV-antigens were detected by immunohistochemical technique and HBV genes were examined with in situ hybridization.RESULTS In 20 cases of cholangiocarcinoma, the positive detection rate of HBxAg, pre-S1, pre-S2, HBsAg and HBcAg was 75%, 40%, 40%, 10% and 0%, respectively, and in the surrounding hepatic tissues of 19 cases the positive rates were 84.2%, 47.9%, 47.9%, 31.6% and 31.6%. Among 40 cases of cholangiocarcinoma, the positive rate of HBV-DNA, x gene, pre-s gene, s gene and s gene fell on 77.5%, 70.0%, 47.5%, 40% and 42.5%, respectively, and of the surrounding hepatic tissues in 33 cases, 87.9%, 84.8%, 63.6%, 69.7% and 66.7%.CONCLUSION The development of human primary intrahepatic cholangiocarcinoma bears a close relationship with chronic persistent HBV infection. Particularly, the x gene of HBV and its protein (HBxAg) might play an important role in pathogenesis of hepatic carcinoma.A large number of studies indicate a close relationship between human primary hepatocellular carcinoma and hepatitis B virus (HBV) infection, which is considered generally as an important factor in the development of hepatic carcinoma[1,2]. In human primary hepatic carcinoma, hepatocellular carcinoma is more frequently encountered, while intrahepatic cholangiocarcinoma (ChC), including hepatocholangiocarcinoma (HChC), is relatively less, being 8%-10%[3]. For a long time, the etiology and pathogenesis of intrahepatic cholangiocarcinoma have been unclear. A few reports considered it to be related to infestation with clonorchiasis sinensis[4,5], but never involved with HBV infection. We used immunohistochemical technique and in situ hybridization methods to detect HBV genes and their -related antigens in the tissues of intrahepatic cholangiocarcinoma and its surrounding hepatic tissues for the purpose of exploring the etiology and pathogenesis of intrahepatic cholangiocarcinoma.

Growth inhibiting effects of antisense eukaryotic expression vector of proliferating cell nuclear antigen gene on human bladder cancer cells

Objective To explore the growth inhibiting effects on human bladder cancer by antisense RNA targeting the proliferating cell nuclear antigen (PCNA) gene. Methods The eukaryotic expression vector for antisense PCNA cDNA was constructed and transferred into a bladder cancer EJ cell line. The PCNA expression in the cancer cells was detected by RT-PCR and Western blotting assays. The in vitro proliferation activities of the transferred cells were observed by growth curve,tetrazolium bromide (MTT) colorimetry,tritiated thymidine ( 3H-TdR)incorporation, flow cytometry and clone formation testing,while its in vivo anti-tumor effects were detected on nude mice allograft models.Results After the antisense vector,pLAPSN,was transferred,cellular PCNA expression was inhibited at both protein and mRNA levels. The growth rates of EJ cells were reduced from 27.91% to 62.07% ( P <0.01),with an inhibition of DNA synthesis rate by 52.31% ( P <0.01). Transferred cells were blocked at G 0/G 1 phases in cell-cycle assay,with the clone formation ability decreased by 50.81% ( P <0.01). The in vivo carcinogenic abilities of the transferred cancer cells were decreased by 54.23% ( P <0.05). Conclusions Antisense PCNA gene transfer could inhibit the growth of bladder cancer cells in vitro and in vivo,which provided an ideal strategy for gene therapy of human cancers.

Expression of Human Hepatitis B Virus Surface Antigen Gene in Transgenic Tobacco

Expression of Human hepatitis B virus surface antigen (HBsAg) gene in plant was reported for the first time. The recombinant plasmid pRoKⅡ-HBsAg was constructed by inserting HBsAg gene into the downstream of CaMV 35S promoter of binary vector pRoKⅡ and then introduced into Agrobacterium tumefaciens LBA4404. The kanamycin-resistant plants were obtained by Agrobacterium-mediated transformation system. It was shown that HBsAg gene was expressed in transgenic tobacco plants and their progenies by ELISA. The spherical particles of ψ 22 nm in the leaf extract of trangenic tobacco were observed by immunosorbent electron microscopy.

Construction of Smac gene-containing and human prostate specific antigen promoter-regulated vector and its expression

To construct an eukaryotic expression vector containing Smac gene and study the expression efficiency and specificity of prostate specific antigen（PSA） enhancer/promoter in a possible targeted gene therapy scheme for prostate cancer. Methods： PSA enhancer （PSAE） and promoter （PSAP） sequences were amplified using PCR method. CMV and T7 promoters were deleted from pcDNA3.1-Smac and replaced by the two specific fragments to generate pPSAE-PSAP-Smac. After transfection into different cell lines, the status of cells was observed. And then, we determined the relative concentration of Smac mRNA in RT-PCR. Results： The recombinant plasmid of pPSAE-PSAP-Smac was successfully constructed. And only the prostate cancer cell line PC-3 was suppressed after transfection with pPSAE-PSAP-Smac. However, other nonprostate lines were not. Moreover, the concentration of Smac mRNA regulated by PSA promoter and enhancer was higher in comparison to the CMV promoter-driven control vectors. Conclusion： An expression vector containing the Smac gene （based on elements of the PSA gene regulatory sequences） has been developed and shown to function in prostate cancer cell lines which provides a solid platform for launching clinical studies.

The human application of gene therapy to re-program T-cell specificity using chimeric antigen receptors

The adoptive transfer of T cells is a promising approach to treat cancers. Primary human T cells can be modified using viral and non-viral vectors to promote the specific targeting of cancer cells via the introduction of exogenous T-cell receptors(TCRs) or chimeric antigen receptors(CARs). This gene transfer displays the potential to increase the specificity and potency of the anticancer response while decreasing the systemic adverse effects that arise from conventional treatments that target both cancerous and healthy cells. This review highlights the generation of clinical-grade T cells expressing CARs for immunotherapy, the use of these cells to target B-cell malignancies and, particularly, the first clinical trials deploying the Sleeping Beauty gene transfer system, which engineers T cells to target CD19+ leukemia and non-Hodgkin's lymphoma.

STUDY ON CLONAL EVOLUTION OF ANTIGEN RECEPTORGENES IN CHILDREN WITH LYMPHOID MALIGNANCIES

objective To study the clonal evolution of domestic children with lymphoid malignancies inorder to choose the optimal method for the detection of the minimal residual disease. methods To use the PCRwhich employs 22primers and SSCP, investigating the matched samples obtained at diagnosis and at relapse of 13children with lymphoid malignancies. Results The clonal evolution occurred in 54%, 23%, 38%, 46%, 54%, 62%and 54% of 13 cases by PCR employing IgH, TCRγ, TCRVδ2, - Dδ3, TCRPVJ1, TCRPVJ2, TCRPD1,J2, TCRβD2J2primers respectively. NO change occurred only in one of those cases. Clonal evolution at relapse occurred at 50% ofsamples which had only one band PCR product at diagnosis and 78% of those had multiple bands PCR product atdiagnosis. No differences had been detected between diagnosis and relapse by SSCP analyzing those samples inwhich no band change occurred between that at diagnosis and at relapse in PAGE. Conclusion It should beoptimal that the one band rearranged gene at diagnosis acts as main monitoring marker, simultaneously referringto the main band in multiple bands rearranged gene in order to avoid false negative.

Study of Swine Leukocyte Antigen Class I-3 (SLA-3) Gene for Inbreeding Wuzhishan Pig

To elucidate the structure of SLA-3 alleles on inbred line of Wuzhishan pig （WZSP） population, we examined the partial exon 1, completed exon 2, and partial exon 3 of SLA-3 loci using the reverse transcription-polymerase chain reaction （RT- PCR） and the sequencing-based method in 32 WZSPs. According to pedigree and amplification results, PCR products of 8 WZSPs were selected to clone and sequence. Nine different nucleotide sequences were obtained. After comparing the DNA and protein sequences of the WZSPs SLA-3 alleles with the published GenBank SLA sequences, it was found that the SLA-3 alleles in WZSPs were all novel, but there were very few variations among them. Comparision of SLA-3 and HLA-A protein sequences indicated that there was more sequence homology. Meanwhile, the construction of a phylogenetic tree using the nucleotide sequences of 23 SLA-3 alleles and 1 HLA-A allele represented that the WZSP population owns its unique genetics resource. In this study, the alleles of SLA-3 on WZSP group were successfully detected and analyzed, which provided the firm basis on the genotype of SLA-3 for breeding specific haplotypes WZSPs.

GENE ENGINEERING EB VIRUS MEMBRANE ANTIGEN IN DETECTION OF MA-IgA ANTIBODY(COMPARISON WITH VCA-IgA AND EA-IgA ANTIBODIES)

With gene engineering EB virus membrane antigen as the diagnostic antigen, indirect immunofluo-rescence (IF) assay was used to detect IgA antibody against EB virus membrane antigen (MA-IgA) in sera from 202 nasopharyngeal carcinoma (NPC) patients and 315 controls (normal and patients with other tumors). MA-IgA antibody was positive in 96.8% of the pretreatment NPC patients with a GMT of 1:36.3. MA-IgA detection by this method was more sensitive than EA-IgA detection by IE. In contrast, patients with tumors other than NPC were negative for MA-IgA antibody. 9.1% of VCA-IgA positive persons were MA-IgA positive with a GMT of less than 1:5. No MA-IgA positive was found in VCA-IgA negatives. The results indicated that this method was relatively specific. In the treatment group, the positive rate and GMT of MA-IgA antibody declined with increase in survival time and the decline was faster than VCA-IgA. When recurrence or distant metastasis developed, similar to VCA-IgA and EA-IgA antibodies, the positive rate and GMT of MA-IgA antibody increased to its pretreatment level. Therefore, MA-IgA detection might be valuable in the early diagnosis and monitor of NPC.

Prokaryotic Expression and Antigenic Analysis of Wbkc Gene from Brucella abortus

[ Objective ] This study aimed to clone and express formyltransferase （Wbkc） gene from Brucella abortus in E. coli, purify the expressed protein and analyze its immunogenicity. [Method] A gene encoding 27 -35 ku formyltransferase （Wbkc） was amplified from the genomic DNA of BruceUa abortus by PCR. The amplified fragments were digested with BamH I and Sal I, and inserted into pET28a vector. The constructed recombinant plasmid pET 28a-Wbkc was trans- formed into E. coli BL21 and was induced to express the fusion protein. Subsequently, the protein was purified by histidine-binding resin column chromatography, and the immunogenicity was detected by Western blot assay. The recombinant plasmid was identified by colony PCR, double digestion and sequencing analysis. [ Result] Wbkc was successfully cloned and expressed in E. coli. A specific protein band of 29 ku was detected by SDS-PAGE. Western blot showed specific im- munoreactivity of the purified fusion protein. [ Conclusion] This study provided a solid foundation for further investigating diagnostic proteins for brucellosis and developing Brucella gene-deletion vaccines.

Amplification,cloning,sequencing and expression of the gene encoding the major surface antigen of Toxoplasma gondii isolated in China

According to the published gene sequence of the major surface antigen (P30) of Toxoplasma gondii, a pair of primers were designed and synthesized. Using polymerase chain reaction (PCR), the coding sequences of P30 gene were amplified from a Chinese strain of T. gondii, The amplified gene fragment and plasmid pB220 were digested with EcoRI and BamHI and then ligated. The inserted gene fragment was sequenced by the chain termination method, the reading reveals that nucleotide sequence determined was the same as the P30 sequecne of RH strain pubilished by Burg (1988), except that one base was changed. The recombinant plasmid containing P30 gene was transformed to E. coli DH5α.After temperature inducing culture, the total cellular proteins were analysed by SDS-PAGE and Western blot. The results show that the p30 gene cloned into the plasmid could express in E. coli, and the expression product had immunogenicity.

HSVTK Gene Therapy for CarcinoembryonicAntigen-Producing Human Lung Cancer Cells

The long-term success of gene therapy for cancer relies heavily on the development of effective targeting systems. We investigate the possibility of targeted gene therapy using promoter of carcinoembryonic antigen (CEA) gene. By using luciferase reporter gene, we found that CEA promoter exhibit 16 times high activity in CEA-producing lung cancer cells, A549 than in nonproducing cells, Hela. We also constructed a recombinant expression plasmid pCEATK, in which CEA promoter drives the effector gene, thymidine kinase gene of Herpes Simplex Virus (HSVTK). A549 cells transfected with pCEATK became 865 times more sensitive to ganciclovir (GCV) than the control cells. However, Hela cells transfected with this plasmid remained resistant to GCV. These data indicate the potential for targeted gene therapy using the CEA promoter against CEA-producing tumor cells, such as lung cancer cells.

IL-21和CCL19修饰可提高NKP30 CAR-T细胞对肺癌的杀伤效率并促进其肿瘤浸润

目的探讨细胞因子IL-21和趋化因子CCL19修饰的NKP30 CAR-T细胞是否增强对肺癌的杀伤和浸润作用。方法在NKP30 CAR基础上融合基因IL-21和CCL19构建IL-21-CCL19 NKP30 CAR;CAR-T细胞的培养使用CD3CD28单抗及细胞因子IL-2刺激;流式细胞术检测免疫细胞表型;迁移实验检测IL-21对免疫细胞的迁移作用;乳酸脱氢酶(LDH)及成球实验检测CAR-T细胞的杀伤及浸润能力;酶联免疫斑点技术(ELISPOT)检测IFN-γ的分泌数量;ELISA检测IL-21及CCL19的分泌情况;体内实验中,将肿瘤细胞显微注射到斑马鱼卵黄囊,构建斑马鱼移植瘤模型,24 h后将免疫细胞注射至同样部位,体式荧光显微镜拍摄荧光。结果NKP30配体(B7H6)在正常组织及血液细胞不表达,在肺癌细胞上高表达(90%以上)。IL-21-CCL19 NKP30 CAR-T细胞与NKP30 CAR-T细胞和常规T细胞相比,具有更强的增殖能力、迁移能力及中心记忆T细胞的形成(P<0.001),免疫抑制分子CTLA4与PD1显著降低(P<0.005),对肺癌细胞具有更强的杀伤能力(P<0.001),伴随IFN-γ数量明显增加(P<0.001)。IL-21-CCL19 CAR-T细胞杀伤肺癌细胞中产生大量细胞因子IL‑21(3152.33±526.74 pg/mL)和趋化因子CCL19(1853±211.95 pg/mL)。体内实验中,CAR-T细胞和普通T细胞比较,具有较强的杀伤能力和增殖能力,但2种CAR-T细胞无明显差异(P>0.05)。结论IL-21-CCL19 NKP30 CAR-T细胞更容易浸润到肿瘤内部,有效杀伤肿瘤细胞,同时产生更多的记忆T细胞。

Th1/Th2平衡及HLA-DQA1基因多态性与血液透析导管性感染的相关性

目的:探讨Th1/Th2平衡及人白细胞抗原DQA1(HLA-DQA1)基因多态性与血液透析导管性感染的相关性。方法:选取2020年1月至2024年1月在我院治疗的血液透析导管性感染患者48例作为观察组,同时选取同期血液透析无导管性感染患者260例作为对照组,比较两组Th1、Th2细胞及因子、以及HLA-DQA1基因多态性差异。结果:观察组Th1、Th2、TNF-α、TGF-1、IL-4和IL-6分别为(43.35±9.10)%、(3.10±0.92)%、(46.22±8.87)pg/mL、(50.05±13.36)pg/mL、(1.03±0.35)pg/mL和(40.05±11.65)pg/mL,高于对照组(P<0.05),而Th1/Th2为(14.01±2.20),低于对照组(P<0.05)。观察组和对照组HLA-DQA1基因型差异有统计学意义(P<0.05)。观察组死亡患者TNF-α、IL-4、IL-6分别为(58.07±2.65)pg/mL、(1.22±0.21)pg/mL和(46.67±9.96)ng/L,高于存活患者(P<0.05)。观察组存活和死亡患者HLA-DQA1基因多态性比较差异无统计学意义(P>0.05)。结论:血液透析导管性感染患者Th1、Th2细胞及相关因子水平升高,发生感染和未发生患者HLA-DQA1基因型有所差异,其中TNF-α、IL-4、IL-6与预后有关。