of research plan for MERIT extension. Memory T cell populations with a history of repeated antigen exposure will be generated in humans due to recurring infections (ie, malaria, influenza), chronic and latent infections (CMV, EBV), and cancer. In addition, many vaccines rely on multiple immunizations (prime-boost) to generate adequate levels of immunity to prevent infection. Our long-term goal is to understand the impact of antigen-exposure history on the properties ofthe resulting memory T cell populations. The significance of these studies lies in providing the basic information necessary to rationally design next generation vaccines with the capacity to protect against diseases of global import such as malaria, HIV and TB that have proven intractable to current vaccine efforts and to lay the groundwork for protective vaccines against emerging and pandemic diseases. Our published and unpublished results from the initial ~3.5 year funding period of R37AI42767 reveal that repeated antigen exposure profoundly impacts patterns of gene expression in the resulting memory CD8 T cell compartment. Functional studies carried out in concert reveal that repeated antigen exposure also alters T cell localization in the steady state and negatively impacts memory maintenance and proliferative capacity in response to antigen re-encounter. Importantly, we also showed that, depending on the nature ofthe pathogen, repeated antigen exposure can either increase or decrease the per cell protective capacity of memory CDS T cells. Despite this progress, many important questions remain to be answered before we can develop ways to utilize repeated antigen-exposure to shape vaccine induced T cell responses for effective protection against specific pathogens. Thus, we retain the long-term goals from our initial funding period for this proposed MERIT extension. Based on the information we generated during the initial funding period and as highlighted in the implications for future studies sections in the progress report, we will focus our efforts in the MERIT extension period on three specific areas 1. Dissecting the molecular basis for diminished persistence of memory CDS T cells generated by repeated antigen stimulation. 2. Understanding how the changes in chemokines, chemokine receptors and adhesion molecules induced by repeated antigen-stimulation influence the steady state and inflammatory based trafficking patterns of the resulting memory populations and how these changes influence pathogen-specific protective immunity. 3. Determining how multiple antigen-encounters regulate the T cell intrinsic and T cell extrinsic (ie, access to specific APC) defects in proliferative response to reinfection. Completion of these studies will not only provide novel information regarding the impact of antigenexposure history on memory T cell but also lay the groundwork for using this information to improve vaccines.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Method to Extend Research in Time (MERIT) Award (R37)
Project #
5R37AI042767-19
Application #
9204722
Study Section
Special Emphasis Panel (NSS)
Program Officer
Kelly, Halonna R
Project Start
1998-04-01
Project End
2018-01-31
Budget Start
2017-02-01
Budget End
2018-01-31
Support Year
19
Fiscal Year
2017
Total Cost
$563,409
Indirect Cost
$191,131
Name
University of Iowa
Department
Microbiology/Immun/Virology
Type
Schools of Medicine
DUNS #
062761671
City
Iowa City
State
IA
Country
United States
Zip Code
52246
Van Braeckel-Budimir, Natalija; Varga, Steven M; Badovinac, Vladimir P et al. (2018) Repeated Antigen Exposure Extends the Durability of Influenza-Specific Lung-Resident Memory CD8+ T Cells and Heterosubtypic Immunity. Cell Rep 24:3374-3382.e3
Shan, Qiang; Zeng, Zhouhao; Xing, Shaojun et al. (2017) The transcription factor Runx3 guards cytotoxic CD8+ effector T cells against deviation towards follicular helper T cell lineage. Nat Immunol 18:931-939
Van Braeckel-Budimir, Natalija; Gras, Stephanie; Ladell, Kristin et al. (2017) A T Cell Receptor Locus Harbors a Malaria-Specific Immune Response Gene. Immunity 47:835-847.e4
Slütter, Bram; Van Braeckel-Budimir, Natalija; Abboud, Georges et al. (2017) Dynamics of influenza-induced lung-resident memory T cells underlie waning heterosubtypic immunity. Sci Immunol 2:
Gullicksrud, Jodi A; Li, Fengyin; Xing, Shaojun et al. (2017) Differential Requirements for Tcf1 Long Isoforms in CD8+ and CD4+ T Cell Responses to Acute Viral Infection. J Immunol 199:911-919
Itani, Farah R; Sinha, Sushmita; Brate, Ashley A et al. (2017) Suppression of autoimmune demyelinating disease by preferential stimulation of CNS-specific CD8 T cells using Listeria-encoded neuroantigen. Sci Rep 7:1519
He, Bing; Xing, Shaojun; Chen, Changya et al. (2016) CD8+ T Cells Utilize Highly Dynamic Enhancer Repertoires and Regulatory Circuitry in Response to Infections. Immunity 45:1341-1354
Doll, Katherine L; Pewe, Lecia L; Kurup, Samarchith P et al. (2016) Discriminating Protective from Nonprotective Plasmodium-Specific CD8+ T Cell Responses. J Immunol 196:4253-62
Kim, Marie T; Kurup, Samarchith P; Starbeck-Miller, Gabriel R et al. (2016) Manipulating Memory CD8 T Cell Numbers by Timed Enhancement of IL-2 Signals. J Immunol 197:1754-61
Kim, Marie T; Richer, Martin J; Gross, Brett P et al. (2015) Enhancing Dendritic Cell-based Immunotherapy with IL-2/Monoclonal Antibody Complexes for Control of Established Tumors. J Immunol 195:4537-44

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