Vaccines, Blood & Biologics
Disease-causing Gut Bacteria: Improving Vaccine Safety and Efficacy of Combination Vaccines to Protect Against Diarrheal Diseases and Select Agents
Principal Investigator: Dennis J. Kopecko, PhD
Office / Division / Lab: OVRR / DBPAP / LESTD
Intestinal bacteria cause about 5 million cases of diarrhea each year in the United States and annually kill more than 2 million children worldwide. The development of vaccines to protect against these diseases is impeded by the lack of detailed understanding of how specific bacteria interact with the human body during infections and how the immune system responds to these infections.
Therefore, we are analyzing the bacterial genes responsible for the changes in human cells and organs that are part of the development of disease. We are also developing animal models of disease and studying the animal and human immune responses that protect against illness. This information helps us to evaluate new vaccine products to determine their safety and ability to trigger protective immune responses and to analyze data on vaccine manufacture and the stability of manufactured products.
Enteric bacterial diseases cause approximately 5 million episodes of diarrhea per year in the U.S. and kill more than 2 million children worldwide annually. Additionally, the threat of the use of highly infectious microbial pathogens as offensive bioterrorist (BT) weapons poses an international threat.
A lack of understanding of specific host-bacterial interactions and immune responses has limited the development of enteric vaccines. However, the safety of certain mutant attenuated strains has led to proposals to use them as carriers of foreign antigens in multivalent vaccines against diarrheal or other diseases. Therefore, we are evaluating a large number of attenuated enteric bacterial mutants for use as live oral vaccines for protection against various diarrheal diseases (e.g. cholera, typhoid fever, shigellosis, and ETEC disease) and bioterrorist threats ( e.g., anthrax). Improved understanding of host-pathogen interactions continues to help us to develop and assess increased safety of attenuated mutants. In addition, new combination live, oral vaccines are being studied to optimize animal models to assess immunogenicity, strain stability, and establish potential correlates of protection.
Our laboratory conducts studies into host-enteric bacterial pathogen interactions to define new components that affect vaccine safety and evaluate procedures to assess the safety of new candidate vaccines. In addition, animal model development and immunological studies are employed to assess the immunogenicity, effectiveness, stability/safety, and potential immune correlates of protection for live, oral attenuated single purpose or multivalent vaccines. We have also participated in collaborative projects aimed at increasing the stability of dried, live vaccines (i.e. to remove the requirement for storage in refrigerator and to extend useful shelf life).
This research will enhance our regulatory abilities by providing tools (e.g. defined antigens, new immunological or other assays and modified animal models) for evaluating the safety and effectiveness of new, live, combination oral enteric bacterial carrier vaccines. Identification of host-pathogen interactions may also lead to new diagnostic tools for enhanced detection of these disease agents that will be useful in evaluating vaccines.
J Autoimmun 2012 Dec;39(4):294-303
Porphyromonas gingivalis promotes Th17 inducing pathways in chronic periodontitis.
Moutsopoulos NM, Kling HM, Angelov N, Jin W, Palmer RJ, Nares S, Osorio M, Wahl SM
Infect Immun 2012 Aug;80(8):2929-39
Campylobacter jejuni-mediated induction of CC and CXC chemokines and chemokine receptors in human dendritic cells.
Hu L, Bray MD, Geng Y, Kopecko DJ
Cancer Gene Ther 2012 Jun;19(6):393-401
Targeted therapy via oral administration of attenuated Salmonella expression plasmid-vectored Stat3-shRNA cures orthotopically transplanted mouse HCC.
Tian Y, Guo B, Jia H, Ji K, Sun Y, Li Y, Zhao T, Gao L, Meng Y, Kalvakolanu DV, Kopecko DJ, Zhao X, Zhang L, Xu D
Cancer Immunol Immunother 2012 Nov;61(11):1977-87
Antitumor effects of Stat3-siRNA and endostatin combined therapies, delivered by attenuated Salmonella, on orthotopically implanted hepatocarcinoma.
Jia H, Li Y, Zhao T, Li X, Hu J, Yin D, Guo B, Kopecko DJ, Zhao X, Zhang L, Xu DQ
Biochem Biophys Res Commun 2011 Dec 16;416(3-4):270-6
Effects of a human plasma membrane-associated sialidase siRNA on prostate cancer invasion.
Li X, Zhang L, Shao Y, Liang Z, Shao C, Wang B, Guo B, Li N, Zhao X, Li Y, Xu D
Vaccine 2011 Mar 24;29(15):2761-71
Room temperature stabilization of oral, live attenuated Salmonella enterica serovar Typhi-vectored vaccines.
Ohtake S, Martin R, Saxena A, Pham B, Chiueh G, Osorio M, Kopecko D, Xu D, Lechuga-Ballesteros D, Truong-Le V
Cancer Gene Ther 2010 Aug 13; (12):844-54
Enhanced tumor suppression in vitro and in vivo by co-expression of survivin-specific siRNA and wild-type p53 protein.
Shao Y, Liu Y, Shao C, Hu J, Li X, Li F, Zhang L, Zhao D, Sun L, Zhao X, Kopecko DJ, Kalvakolanu DV, Li Y, Xu DQ
Infect Immun 2009 Oct;77(10):4529-37
Nod1/Nod2-mediated recognition plays a critical role in induction of adaptive immunity to anthrax after aerosol exposure.
Loving CL, Osorio M, Kim YG, Nuñez G, Hughes MA, Merkel TJ
Int J Med Microbiol 2009 Apr;299(4):233-46
Genetic stability of vaccine strain Salmonella Typhi Ty21a over 25 years.
Kopecko DJ, Sieber H, Ures JA, Fürer A, Schlup J, Knof U, Collioud A, Xu D, Colburn K, Dietrich G
Infect Immun 2009 Apr;77(4):1475-82
Anthrax protective antigen delivered by Salmonella enterica serovar Typhi Ty21a protects mice from a lethal anthrax spore challenge.
Osorio M, Wu Y, Singh S, Merkel TJ, Bhattacharyya S, Blake MS, Kopecko DJ
Methods Mol Biol 2009;487:161-87
Bacterial delivery of siRNAs: a new approach to solid tumor therapy.
Xu DQ, Zhang L, Kopecko DJ, Gao L, Shao Y, Guo B, Zhao L
Infect Immun 2008 Nov;76(11):5294-304
Enhanced Microscopic Definition of Campylobacter jejuni 81-176 Adherence to, Invasion into, Translocation across, and Exocytosis from Polarized Human Intestinal Caco-2 Cells.
Hu L, Tall BD, Curtis SK, Kopecko DJ
Curr Issues Mol Biol 2008;10(1-2):13-6
Considerations in the development of live biotherapeutic products for clinical use.
Ross JJ, Boucher PE, Bhattacharyya SP, Kopecko DJ, Sutkowski EM, Rohan PJ, Chandler DKF, Vaillancourt J
Clin Cancer Res 2008 Jan 15;14(2):559-68
Effects of Plasmid-Based Stat3-Specific Short Hairpin RNA and GRIM-19 on PC-3M Tumor Cell Growth.
Zhang L, Gao L, Li Y, Lin G, Shao Y, Ji K, Yu H, Hu J, Kalvakolanu DV, Kopecko DJ, Zhao X, Xu DQ
Vaccine 2007 Aug 14;25(33):6167-75
Core-linked LPS expression of Shigella dysenteriae serotype 1 O-antigen in live Salmonella Typhi vaccine vector Ty21a: Preclinical evidence of immunogenicity and protection.
Xu de Q, Cisar JO, Osorio M, Wai TT, Kopecko DJ
Cancer Res 2007 Jun 15;67(12):5859-64
Intratumoral delivery and suppression of prostate tumor growth by attenuated Salmonella enterica serovar typhimurium carrying plasmid-based small interfering RNAs.
Zhang L, Gao L, Zhao L, Guo B, Ji K, Tian Y, Wang J, Yu H, Hu J, Kalvakolanu DV, Kopecko DJ, Zhao X, Xu DQ
Infect Immun 2006 May;74(5):2697-705
Campylobacter jejuni Induces Maturation and Cytokine Production in Human Dendritic Cells.
Hu L, Bray MD, Osorio M, Kopecko DJ
Microb Pathog 2006 Mar;40(3):91-100
Signal transduction events involved in human epithelial cell invasion by Campylobacter jejuni 81-176.
Hu L, McDaniel JP, Kopecko DJ
Microbiology 2005 Sep;151(Pt 9):3097-105
Ca2+ release from host intracellular stores and related signal transduction during Campylobacter jejuni 81-176 internalization into human intestinal cells.
Hu L, Raybourne RB, Kopecko DJ
Clin Cancer Res 2005 Sep 1;11(17):6333-41
Down-regulation of signal transducer and activator of transcription 3 expression using vector-based small interfering RNAs suppresses growth of human prostate tumor in vivo.
Gao L, Zhang L, Hu J, Li F, Shao Y, Zhao D, Kalvakolanu DV, Kopecko DJ, Zhao X, Xu DQ
Infect Immun 2004 Nov;72(11):6382-9
Cytokine response to infection with Bacillus anthracis spores.
Pickering AK, Osorio M, Lee GM, Grippe VK, Bray M, Merkel TJ