Source: MICHIGAN STATE UNIV submitted to NRP
FOR LAB TO FIELD: DEVELOP ENDOSYMBIOTIC BACTERIA WOLBACHIA FOR VECTOR-BORNE DISEASE CONTROL
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
HATCH
Reporting Frequency
Annual
Accession No.
1021359
Grant No.
(N/A)
Cumulative Award Amt.
(N/A)
Proposal No.
(N/A)
Multistate No.
(N/A)
Project Start Date
Jan 1, 2020
Project End Date
Dec 31, 2024
Grant Year
(N/A)
Program Code
[(N/A)]- (N/A)
Recipient Organization
MICHIGAN STATE UNIV
(N/A)
EAST LANSING,MI 48824
Performing Department
Microbiology & Molecular Genetics
Non Technical Summary
Wolbachia is maternally transmitted, Gram-negative endosymbiotic bacterium that infects more than 65% of all insect species. The ability of Wolbachia to spread through cytoplasmic incompatibility (CI) and induce resistance to a variety of human pathogens has led to development of Wolbachia-based strategies for both the suppression and replacement of medically important mosquito species. This includes reports that Wolbachia was deployed successfully into field settings for either blocking dengue transmission by Wolbachia or eliminating dengue vector population. To understand the molecular mechanism underlying Wolbachia-mediated resistance to dengue virus, we have shown that Wolbachia induces ROS-dependent activation of the Toll pathway to control dengue virus in the mosquito Ae. aegypti. However, evidences also indicate multiple mechanisms may work together to form a system with high efficacy to induce viral interference. The long-term goal of our research is to understand the interactions between the symbiotic intracellular bacterium Wolbachia and its insect hosts and develop Wolbachia as a novel tool to combat vector-borne diseases, including dengue, Zika and malaria. Toward them, we aim to conduct both basic studies in the laboratory and implementation studies in the field. Specifically, our basic studies are focusing on: 1) understanding the molecular mechanisms of Wolbachia-mediated viral and Plasmodium interference in mosquito vectors, and 2) dissecting the roles of mosquito innate immunity in promoting Wolbachia symbiosis with novel hosts. Our implementation studies are focusing on: 1) developing Wolbachia as a microbial insecticide to sustainably control dengue, Zika and malaria, and adapt & extend this technology to control agriculturally important insect pests; 2) manipulating mosquito sex determination pathways for mass production of Wolbachia-infected male mosquitoes. Due to the significance of vector borne disease control in public health, our implementation studies will extensively involve international collaboration in disease endemic countries as we have accomplished in Asia and Latin America. We anticipate the knowledge generated from the above studies will facilitate the development of Wolbachia-based biocontrol strategies for the current global effort on vector-borne disease control.
Animal Health Component
40%
Research Effort Categories
Basic
40%
Applied
40%
Developmental
20%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
7213110113070%
3110860111010%
7223110110120%
Knowledge Area
311 - Animal Diseases; 722 - Zoonotic Diseases and Parasites Affecting Humans; 721 - Insects and Other Pests Affecting Humans;

Subject Of Investigation
3110 - Insects; 0860 - Endangered species;

Field Of Science
1101 - Virology; 1130 - Entomology and acarology; 1110 - Parasitology;
Goals / Objectives
The long-term goal of our research is to understand the interactions between the symbiotic intracellular bacterium Wolbachia and its insect hosts and develop Wolbachia as a novel tool to combat vector-borne diseases, including dengue, Zika and malaria. Toward these, we conduct both basic studies in the laboratory and implementation studies in the field. Specifically, our basic studies are focusing on: 1) understanding the molecular mechanisms of Wolbachia-mediated viral and Plasmodium interference in mosquito vectors, and 2) dissecting the roles of mosquito innate immunity in promoting Wolbachia symbiosis with novel hosts. Our implementation studies are focusing on: 1) developing Wolbachia as a microbial insecticide to sustainably control dengue, Zika and malaria, and adapt & extend this technology to control agriculturally important insect pests; 2) manipulating the mosquito sex determination pathway for mass production of Wolbachia-infected male mosquitoes. Due to the global significance of vector borne disease control in public health, our implementation studies will extensively involve international collaboration in disease endemic countries as we have accomplished in Asia and Latin America.
Project Methods
We will further define the host and microbial factors that determine Wolbachia-mediated resistance to dengue, Zika virus and Plasmodium. Our central hypothesis is that Wolbachia utilizes host lipid resource for its proliferation, resulting in a hostile physiological environment for dengue, Zika virus, and Plasmodium with altered gut microbiota, elevated ROS and reduced/compromised receptors that involve in entrance into mosquito cells. To test them, we will characterize the role of lipid metabolism in regulation of Wolbachia density in mosquitoes, determine the role of ROS in Wolbachia-mediated pathogen interference in both Aedes and Anopheles mosquito, and describe the mechanism underlying Wolbachia-mediated inhibition of entrance of pathogens into to mosquito cells. Understanding the mechanism underlying Wolbachia-mediated pathogens interference will facilitate the development of a better mosquito strain, with high pathogen inhibition but low fitness cost. It will also aid in predication of the possibility for pathogens to develop resistance to the blocking effect such that a strategy of resistance management can be prepared in advance. As such, they will facilitate the development of Wolbachia as a practical tool to control dengue, Zika and malaria.We will further test the combined IIT-SIT in the areas with dengue transmission, including dengue hot spots in Guangzhou urbane area and Merida, to measure its impact on disease transmission by targeting A. albopictus and A. aegypti, respectively. Effort will also be put to increase its cost-effectiveness such that it can be effectively deployed in area-wide application. Specifically, we will develop and test new entomological indicators that have proven links with disease transmission and prepare for randomized cluster trials. We will also develop a RNA interference (RNAi)-based system to produce Wolbachia-infected male mosquito for population suppression. We will identify the female specific essential genes, including transformer-2 and female splice variant of double sex (dsx), in Wolbachia-infected mosquito and test the impact of their knock-down on male production. Then, we will express their dsRNA through E. coli and validate their uses in male production after feeding them to mosquito larvae. This project will allow us to develop a microbial insecticide by taking advantaging of two bacteria, one (Wolbachia) for sterilizing insect and another (E coli expressing the female lethal genes) for purifying the product, while both are highly effective, affordable, and compatible with safety issue in regulation policy. We will also further develop a Wolbachia-based population suppression / replacement strategy as an area-wide applicable, eco-friendly, cost-effective and sustainable intervention to target A. stephensi population and to prevent risk of urban malaria transmission in either India or Africa. Toward that, we will work on feasibility and preparation for field trials, followed by an area-wide application of the above strategy for malaria control. Below are specific aims: 1). Evaluate the key mosquito parameters which determine the dynamics and success of population elimination following release into the field. wAlbB-infected A. stephensi females will be outcrossed with wild-type male mosquitoes collected from fields for seven generations to homogenize the genetic background. The resultant outcrossed mosquitoes will be used to confirm the efficiency of maternal transmission, strength of CI, female fecundity, male mating competitiveness, and mosquito longevity. These data will be used in a mathematic model to predict the dynamic of population suppression and replacement in the field. 2). Determine the effect of Wolbachia wAlbB infection on the vector competence of A. stephensi for currently circulating endemic malaria parasite species. We will validate malaria parasite blocking effect in the wAlbB-infected A. stephensi. The above outcrossed mosquito will be tested for vector competence for the currently circulating malaria parasite species, including P. falciparum and P. vivax, using blood of patients through local clinics. 3). Introduce novel Wolbachia strains into A. stephensi. The Wolbachia strain wPip will be introduced into A. stephensi to generate a mosquito strain that is incompatible with wAlbB-infected mosquito. A. stephensi with superinfection of wAlbB and wPip will also be generated by transfer wPip into wAlbB-infected A. stephensi. These strains can be used to remove the wAlbB-infected mosquito in the field when necessary.

Progress 01/01/20 to 09/30/20

Outputs
Target Audience:I have given six presentations during this report period to introduce Wolbachia-based strategies for vector-borne disease control. This includes the Bill Melinda Gates Foundation's Collaborative Meeting for Large Scale Mosquito Rearing and Release, 2018 World Life Science,International Atomic Energy Agency (IAEA)'s Regional Training Course (RAS5082), and 2019 Annual Meeting for the Entomology Society of America,Center for Infectious Disease Dynamics of Penn State University. I also hosted the Food and Agriculture Organization of the United Nations (FAO)/IAEA's Interregional Workshop on "Use of SIT for Decision Makers: INT5155- Sharing Knowledge on the Sterile Insect and Related Techniques for the Integrated Area-Wide Management of Insect Pests and Human Disease Vectors", withparticipants from 15 countries. I was also invited by the FAO/IAEA to review and update the Thematic Plan for the Development and Application of the Sterile Insect Technique (SIT) and Related Control Methods for Disease Transmitting Mosquitoes. Changes/Problems:There are nomajor changes/problems in approach. What opportunities for training and professional development has the project provided?I have given many classes, presentation and workshop to the people interested in developing Wolbachia for vector control. Training is provided to graduate students and postdocs when they work on the project in my lab. Through hosting workshop, I have provided hand-on trainings toscientists from disease endemic countries on mosquito mass rearing, quality control and release which are essential steps to develop our technology for disease control. How have the results been disseminated to communities of interest?We have shared our experiencein development of combined Wolbachia and radiation-based sterile technique for mosquito control withinternational community throughpresentation in conference, scientific journal publication, internet, social media, and public media. In addition, we also disseminatethe knowledge through the international organization, such as IAEA.For example,I have participatedin update onIAEA's Thematic Plan for the Development and Application of the Sterile Insect Technique (SIT) and Related Control Methods for Disease Transmitting Mosquitoes (https://www.iaea.org/resources/thematic-plan/thematic-plan-for-the-development-and-application-of-the-sterile-insect-technique-sit-and-related-genetic-and-biological-control-methods-for-disease-transmitting-mosquitoes). What do you plan to do during the next reporting period to accomplish the goals?We will continue exploring the potential to developWolbachiafor malaria control through both basic research in the lab and applied studies in the field andseeking fund supports to our work, including from NIHand Bill & Melinda GatesFoundation. By focusing on the mechanisms of Wolbachia-mediated pathogen interference, mosquitosex determination and sex-specific development, we will improve the cost-effectiveness of the use of Wolbachia for vector control. Through broad international collaborations with the disease endemic countries, we will not only learn what is needed to improve the technology but also effectively takeour knowledge from the lab to the fieldfor disease control.

Impacts
What was accomplished under these goals? Through the successfulfield trial, we have generated knowledge on the use of combined Wolbachia- and radiation-based sterile technique for vector-born disease control, raising great interests by global industry leaders including Bayer and Verily who orientate their research and development (R&D) to improving and deploying the Wolbachia technology as an component of integrated vector management. In addition to Mexico, we also provide support ondeveloping Wolbachia to control dengue for Singapore government, where a new mosquito factory was opened in itsNational Environment Agencylast December. Our progress has alsolaid a foundation to develop a similar concept for both malaria control and plant protection. Toward that,we are working withthe Hawaii governmentto control avian malaria by developingWolbachiato eradicateCulex mosquito vector,havesubmitted a revised proposal to NIH tostudy Wolbachia-malaria parasite interactions in Anopheles mosquito vectors, and have introduced a plant virus-inhibiting Wolbachia into planthopper for mitigating disease transmission in the rice plant.

Publications

  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Liang, X, Liu, J., Bian, G., Xi, Z. (2020). Wolbachia inter-strain competition and inhibition of expression of cytoplasmic incompatibility in mosquito. Front Microbiol. 11:1638. doi: 10.3389/fmicb.2020.01638.
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Lu P, Sun Q, Fu P, Li K, Liang X, Xi Z. (2020). Wolbachia inhibits binding of dengue and Zika Viruses to mosquito cells. Front Microbiol. 11:1750. doi: 10.3389/fmicb.2020.01750.
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Peng, W., Yu,. S, Handler A.M., Tu, Z., Saccone, G., Xi, Z., Zhang, H. (2020). miRNA-1-3p is an early embryonic male sex-determining factor in the Oriental fruit fly Bactrocera dorsalis. Nature Communications. 11(1):932. doi: 10.1038/s41467-020-14622-4.
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Ju, J., Bing, X., Zhao, D., Guo, Y., Xi, Z., Hoffmann, A.A., Zhang, K., Huang, H., Gong, J., Zhang, X., Hong, X. (2020). Wolbachia supplement biotin and riboflavin to enhance reproduction in planthoppers. ISME Journal. 14(3):676-687. doi: 10.1038/s41396-019-0559-9
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Zhang, D., Xi, Z., Li, Y., Wang, X., Yamada, H., Qiu, J., Liang, Y., Zhang, M., Wu, Y., Zheng, X. (2020). Toward implementation of combined incompatible and sterile insect techniques for mosquito control: Optimized chilling conditions for handling Aedes albopictus male adults prior to release. PLoS Negl Trop Dis. 14(9):e0008561. doi: 10.1371/journal.pntd.0008561.