Source: MISSISSIPPI STATE UNIV submitted to
PREVENTION OF ENTERIC SEPTICEMIA OF CATFISH BY NOVEL LIVE ATTENUATED VACCINES
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
EXTENDED
Funding Source
Reporting Frequency
Annual
Accession No.
1008811
Grant No.
2016-67015-24909
Project No.
MISV-371720
Proposal No.
2015-07054
Multistate No.
(N/A)
Program Code
A1221
Project Start Date
Feb 1, 2016
Project End Date
Jan 31, 2020
Grant Year
2016
Project Director
Karsi, A.
Recipient Organization
MISSISSIPPI STATE UNIV
(N/A)
MISSISSIPPI STATE,MS 39762
Performing Department
CVM Basic Science Department
Non Technical Summary
Channel catfish farming is the largest aquaculture industry in the U.S., and Edwardsiella ictaluri is recognized as the most economically important bacterial pathogen of catfish. The type six secretion system (T6SS) and universal stress proteins (USP) are essential for E. ictaluri virulence in catfish. However, critical work needs to be conducted to develop safe and efficacious live attenuated vaccines (LAV) against E. ictaluri. Our long-term goal is to characterize mechanisms of E. ictaluri pathogenesis in order to develop effective control strategies for the disease. The immediate objective of this study is to develop novel LAVs by mutating T6SS and USP genes and by characterizing mutants' safety and efficacy in catfish. The rationale of the proposed research is that T6SS and USPs are essential for E. ictaluri virulence in catfish and mutation of genes in these systems is expected to yield safe and efficacious vaccines for catfish. This study is significant because of the large economic impact enteric septicemia has on the catfish industry. Current disease treatments are often ineffective, costly, and can result in drug resistance or environmental contamination. Therefore, vaccine-based strategies for control of diseases are essential to support the development of an environmentally and economically sustainable aquaculture industry in the U.S.
Animal Health Component
100%
Research Effort Categories
Basic
100%
Applied
0%
Developmental
0%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
31137101100100%
Knowledge Area
311 - Animal Diseases;

Subject Of Investigation
3710 - Catfish;

Field Of Science
1100 - Bacteriology;
Goals / Objectives
Construct T6SS and USP mutantsCharacterize T6SS and USP mutants
Project Methods
-EffortsThe type six secretion system (T6SS) and universal stress protein (USP) genes will be deleted in-frame. Then, attenuation and efficacy of mutants will be characterized in specific pathogen free catfish by immersion exposure. Briefly, catfish will be vaccinated by immersion, and three weeks following vaccination, fish will be immersion exposed to virulent parent strain. Percent mortalities will be calculated after two weeks to evaluate protection levels.-EvaluationPercent mortalities will be arcsine-transformed and compared by ANOVA. If significant differences among vaccine candidates are found at α = 0.05, means will be separated using the least-significant-difference test.

Progress 02/01/17 to 01/31/18

Outputs
Target Audience:Target Audiences Microbiologists Veterinarians Fish health research community Catfish producers Efforts Science-based knowledge has been delivered in laboratory teaching, fish health-related courses, and workshops. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?- This project has provided training and professional development opportunities for two postdocs (Hossam Abdelhamed and Jingjun Lu) and four doctoral students (Ali Akgul, Safak Kalindamar, Adef Kordon, and Iman Ibrahim). - Hossam Abdelhamed accepted a faculty position in the College of Veterinary Medicine at Mississippi State University. - Jingjun Lu accepted a position in Saint Jude Children's Hospital. - Ali Akgul accepted a post-doctoral position in the College of Veterinary Medicine at the University of Florida. - Safak Kalindamar accepted a faculty position in a university in Turkey. How have the results been disseminated to communities of interest?- Five presentations were given at scientific conferences. - One manuscript was published in a peer-reviewed journal, Frontiers in Microbiology (https://doi.org/10.3389/fmicb.2017.02638). - One manuscript was submitted to peer-reviewed journals, PLOS One. What do you plan to do during the next reporting period to accomplish the goals?Goal one: Construct T6SS and USP mutants. - None. This goal is completed. Goal two: Characterize T6SS and USP mutants - Verify safety and efficacy of promising mutants in catfish fry - Assess vaccine-induced innate and adaptive responses.

Impacts
What was accomplished under these goals? 1) Major activities completed Goal one: Construct T6SS and USP mutants.? - All T6SS and USP mutants were constructed. Goal two: Characterize T6SS and USP mutants. - Attenuation of mutants was determined in catfish fry - Efficacy of mutants was determined in catfish fry. 2) Specific objectives met Goal one: Construct T6SS and USP mutants. - Construction of all T6SS and USP mutants were completed. Goal two: Characterize T6SS and USP mutants - Initial screening of mutants' virulence and efficacy in catfish fry was completed. 3) Significant Results Achieved Initial characterization indicated the presence of attenuated and protective mutants in catfish fry. 4) Key outcomes or other accomplishments realized Several USP and T6SS genes contribute to E. ictaluri virulence in catfish Phagocytosis of attenuated mutants by macrophages was higher compared to wild-type. Uptake of E. ictaluri opsonized with sera from vaccinated catfish was more efficient.

Publications

  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Kordon A, Abdelhamed H, Ahmed H, Park J, Karsi A, Pinchuk L. 2017. Phagocytic and bactericidal properties of channel catfish peritoneal macrophages exposed to Edwardsiella ictaluri live attenuated vaccine and wild-type strains. Frontiers in Microbiology (https://doi.org/10.3389/fmicb.2017.02638).
  • Type: Theses/Dissertations Status: Submitted Year Published: 2017 Citation: Akgul A. The role of universal stress proteins in Edwardsiella ictaluri virulence. Mississippi State University.
  • Type: Theses/Dissertations Status: Submitted Year Published: 2017 Citation: Kalindamar S. Characterization of type VI secretion system in Edwardsiella ictaluri. Mississippi State University.
  • Type: Conference Papers and Presentations Status: Other Year Published: 2017 Citation: Kalindamar S, Abdelhamed H, Kordon A, Lu J, Kumru S, Tekedar H, Pinchuk L, Karsi A. 2017. Characterization of type VI secretion system in Edwardsiella ictaluri. American Society for Microbiology South Central Branch Meeting, Little Rock, AR, USA.
  • Type: Conference Papers and Presentations Status: Other Year Published: 2017 Citation: Ibrahim I, Abdelhamed H, Baumgartner W, Lawrence M, Karsi A. 2017. Assessment of portals of entry for attenuated and wild-type Edwardsiella ictaluri. American Fisheries Society Fish Health Section Annual Meeting, East Lansing, MI, USA.
  • Type: Conference Papers and Presentations Status: Other Year Published: 2017 Citation: Ibrahim I, Abdelhamed H, Baumgartner W, Awadin W, Lawrence M, Karsi A. 2017. Pathological and ultrastructural effects of live attenuated Edwardsiella ictaluri vaccines. American Fisheries Society Fish Health Section Annual Meeting, East Lansing, MI, USA.
  • Type: Conference Papers and Presentations Status: Other Year Published: 2017 Citation: Abdelhamed H, Lawrence ML, Karsi A. 2017. A novel vaccine candidate protects catfish against enteric septicemia. American Fisheries Society Fish Health Section Annual Meeting, East Lansing, MI, USA.
  • Type: Conference Papers and Presentations Status: Other Year Published: 2017 Citation: Kalindamar S, Abdelhamed H, Kordon A, Al-Janabi N, Lu J, Tekedar H, Karsi A. 2017. The effect of Hcp family proteins of type VI secretion system in Edwardsiella ictaluri virulence. American Society for Microbiology ASM Microbe 2017 Meeting, New Orleans, LA, USA.


Progress 02/01/16 to 01/31/17

Outputs
Target Audience:The target audiences include: Fish health research community Veterinarians Catfish producers Microbiologists Efforts Science-based knowledge has been delivered in laboratory teaching, fish health related courses, and workshops. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?This project has provided training and professional development opportunities for two postdocs (Hossam Abdelhamed and Jingjun Lu), three doctoral students (Ali Akgul, Safak Kalindamar, and Adef Kordon), and a visiting scholar (Iman Ibrahim). How have the results been disseminated to communities of interest?Results have been presented at scientific conferences and will be published in peer-reviewed journals. What do you plan to do during the next reporting period to accomplish the goals? Finalize construction of all T6SS and USP mutants. Determine safety and efficacy of mutants in catfish fingerlings. Confirm safety and efficacy of potential vaccine candidates in catfish fry. Start testing tissue persistence and immune responses of vaccine candidates.

Impacts
What was accomplished under these goals? 1) Major activities completed -Goal one: Construct T6SS and USP mutants Construction of T6SS mutants was completed. Construction of USP mutants was completed. -Goal two: Characterize T6SS and USP mutants Attenuation of mutants was determined in catfish fingerlings. Efficacy of mutants was determined in catfish fingerlings. 2) Specific objectives met -Goal one Construction of T6SS and USP mutants was completed. -Goal two Initial screening of mutants' virulence and efficacy was completed. 3) Significant Results Achieved We were able to construct all in-frame deletion mutants. Initial characterization indicated the presence of attenuated and protective mutants. 4) Key outcomes or other accomplishments realized Several USP and T6SS genes contribute to E. ictaluri virulence in catfish.

Publications

  • Type: Conference Papers and Presentations Status: Other Year Published: 2016 Citation: Akgul A, Akgul A, Lawrence ML, Karsi A. 2016. Expression of Edwardsiella ictaluri stress-related genes under various stresses. American Society for Microbiology South Central Branch Meeting, Lafayette, LA, USA.
  • Type: Conference Papers and Presentations Status: Other Year Published: 2016 Citation: Kalindamar S, Abdelhamed H, Tekedar H, Karsi A. 2016. Construction and evaluation of an Edwardsiella ictaluri virulence protein F mutant. 2nd International Conference of Fish and Shellfish Immunology. Portland, MA, USA.
  • Type: Conference Papers and Presentations Status: Other Year Published: 2016 Citation: Akgul A, Akgul A, Tekedar H, Lawrence M, Karsi A. 2016. Expression analysis of universal stress proteins in Edwardsiella ictaluri. American Society for Microbiology ASM Microbe 2016 Meeting, Boston, MA, USA.