Objective:Our objective was to construct a recombinant bacillus Calmette-Guérin vaccine(rBCG) that secretes human interferon-alpha 2b(IFNα-2b) and to study its immunogenicity and in vitro antitumor activity agai...Objective:Our objective was to construct a recombinant bacillus Calmette-Guérin vaccine(rBCG) that secretes human interferon-alpha 2b(IFNα-2b) and to study its immunogenicity and in vitro antitumor activity against human bladder cancer cell lines T24 and T5637.Methods:The signal sequence BCG Ag85B and the gene IFNα-2b were amplified from the genome of BCG and human peripheral blood,respectively,by polymerase chain reaction(PCR).The two genes were cloned in Escherichia coli-BCG shuttle-vector pMV261 to obtain a new recombinant plasmid pMV261-Ag85B-IFNα-2b.BCG was transformed with the recombinant plasmid by electroporation and designated rBCG-IFNα-2b.Mononuclear cells were isolated from human peripheral blood(PBMCs) and stimulated with rBCG-IFNα-2b or wild type BCG for 3 d,and then cultured with human bladder cancer cell lines T24 and T5637.Their cytotoxicities were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay.Results:BCG was successfully transformed with the recombinant plasmid pMV261-Ag85B-IFNα-2b by electroporation and the recombinant BCG(rBCG-IFNα-2b) was capable of synthesizing and secreting cytokine IFNα-2b.PBMC proliferation was enhanced significantly by rBCG-IFNα-2b,and the cytotoxicity of PBMCs stimulated by rBCG-IFNα-2b to T24 and T5627 was significantly stronger in comparison to wild type BCG.Conclusions:A recombinant BCG,secreting human IFNα-2b(rBCG-IFNα-2b),was constructed successfully and was superior to control wild type BCG in inducing immune responses and enhancing cytotoxicity to human bladder cancer cell lines T24 and T5637.This suggests that rBCG-IFNα-2b could be a promising agent for bladder cancer patients in terms of possible reductions in both clinical dosage and side effects of BCG immunotherapy.展开更多
Introduction: Tuberculosis (TB) continues to be a global health challenge and currently only one licensed vaccine is available. For nearly 100 years, the Bacillus Calmette-Guérin (BCG) vaccine has been in use. Wh...Introduction: Tuberculosis (TB) continues to be a global health challenge and currently only one licensed vaccine is available. For nearly 100 years, the Bacillus Calmette-Guérin (BCG) vaccine has been in use. While it provides protection against disseminated TB in infants, its protection against adult and adolescent pulmonary tuberculosis (PTB) is variable. This literature review will provide an overview of the clinical status of candidate TB vaccines and discuss the challenges and future development trends of novel TB vaccine research, in combination with a general overview of the Tuberculosis (TB) disease and Mycobacterium tuberculosis itself. Methods: Bibliographic searches were carried out on medical journal databases, publishers, and aggregators. The most used databases were PubMed, NCBI and MDPI. Publications in English on these and other databases relating to novel TB vaccines were included in this review. Results: Currently, there are 12 main vaccine candidates in various phases of clinical trials, they include four protein or adjuvant vaccines, three viral-vectored vaccines, three mycobacterial whole cells or extract vaccines, and one each of the recombinant life and the attenuated Mycobacterium tuberculosis vaccine. Currently, the most likely candidate vaccines are the M72 + AS01E and Vaccae vaccines. M72 + AS01E is a recombinant fusion protein vaccine candidate, clinical trials showed that administering two doses of M72/AS01E was successful in reducing the development of active TB disease with 50% efficacy. Studies have also proven the efficacy of Vaccae (which is currently in phase III clinical trials) as an adjunctive therapy, with it being curative in conjunction with current therapy. Conclusion: Given the morbidity and mortality suffered globally by M. tuberculosis, it is time to realize the seriousness of the situation and accelerate our commitment and investment to the eradication of this infectious disease. With the number of vaccine candidates currently in clinical trials having promising results, it is imperative to continue these studies and accelerate towards phase III licensure trials if we are to achieve the milestone of “End TB Strategy” by 2035. Today, we are witnessing immense progress in both preclinical and clinical TB vaccine research despite disappointing results from some of the clinical efficacy trials like that of MVA85A. We can revisit the design of vaccines and learn from them. It is important not only to recognize and give credit to those that have tested well in human trials, such as M72 + AS01E, but to expedite and improve its efficacy through funding of its research.展开更多
基金Project(No.2006C30011)supported by the Science and Technology Department of Zhejiang Province of China
文摘Objective:Our objective was to construct a recombinant bacillus Calmette-Guérin vaccine(rBCG) that secretes human interferon-alpha 2b(IFNα-2b) and to study its immunogenicity and in vitro antitumor activity against human bladder cancer cell lines T24 and T5637.Methods:The signal sequence BCG Ag85B and the gene IFNα-2b were amplified from the genome of BCG and human peripheral blood,respectively,by polymerase chain reaction(PCR).The two genes were cloned in Escherichia coli-BCG shuttle-vector pMV261 to obtain a new recombinant plasmid pMV261-Ag85B-IFNα-2b.BCG was transformed with the recombinant plasmid by electroporation and designated rBCG-IFNα-2b.Mononuclear cells were isolated from human peripheral blood(PBMCs) and stimulated with rBCG-IFNα-2b or wild type BCG for 3 d,and then cultured with human bladder cancer cell lines T24 and T5637.Their cytotoxicities were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay.Results:BCG was successfully transformed with the recombinant plasmid pMV261-Ag85B-IFNα-2b by electroporation and the recombinant BCG(rBCG-IFNα-2b) was capable of synthesizing and secreting cytokine IFNα-2b.PBMC proliferation was enhanced significantly by rBCG-IFNα-2b,and the cytotoxicity of PBMCs stimulated by rBCG-IFNα-2b to T24 and T5627 was significantly stronger in comparison to wild type BCG.Conclusions:A recombinant BCG,secreting human IFNα-2b(rBCG-IFNα-2b),was constructed successfully and was superior to control wild type BCG in inducing immune responses and enhancing cytotoxicity to human bladder cancer cell lines T24 and T5637.This suggests that rBCG-IFNα-2b could be a promising agent for bladder cancer patients in terms of possible reductions in both clinical dosage and side effects of BCG immunotherapy.
文摘Introduction: Tuberculosis (TB) continues to be a global health challenge and currently only one licensed vaccine is available. For nearly 100 years, the Bacillus Calmette-Guérin (BCG) vaccine has been in use. While it provides protection against disseminated TB in infants, its protection against adult and adolescent pulmonary tuberculosis (PTB) is variable. This literature review will provide an overview of the clinical status of candidate TB vaccines and discuss the challenges and future development trends of novel TB vaccine research, in combination with a general overview of the Tuberculosis (TB) disease and Mycobacterium tuberculosis itself. Methods: Bibliographic searches were carried out on medical journal databases, publishers, and aggregators. The most used databases were PubMed, NCBI and MDPI. Publications in English on these and other databases relating to novel TB vaccines were included in this review. Results: Currently, there are 12 main vaccine candidates in various phases of clinical trials, they include four protein or adjuvant vaccines, three viral-vectored vaccines, three mycobacterial whole cells or extract vaccines, and one each of the recombinant life and the attenuated Mycobacterium tuberculosis vaccine. Currently, the most likely candidate vaccines are the M72 + AS01E and Vaccae vaccines. M72 + AS01E is a recombinant fusion protein vaccine candidate, clinical trials showed that administering two doses of M72/AS01E was successful in reducing the development of active TB disease with 50% efficacy. Studies have also proven the efficacy of Vaccae (which is currently in phase III clinical trials) as an adjunctive therapy, with it being curative in conjunction with current therapy. Conclusion: Given the morbidity and mortality suffered globally by M. tuberculosis, it is time to realize the seriousness of the situation and accelerate our commitment and investment to the eradication of this infectious disease. With the number of vaccine candidates currently in clinical trials having promising results, it is imperative to continue these studies and accelerate towards phase III licensure trials if we are to achieve the milestone of “End TB Strategy” by 2035. Today, we are witnessing immense progress in both preclinical and clinical TB vaccine research despite disappointing results from some of the clinical efficacy trials like that of MVA85A. We can revisit the design of vaccines and learn from them. It is important not only to recognize and give credit to those that have tested well in human trials, such as M72 + AS01E, but to expedite and improve its efficacy through funding of its research.
