Abstract

Candidate: Jonathan E. Fogle, DVM, has completed a residency in small animal internal medicine at NCSU and is board certified in Veterinary Internal Medicine. Dr. Fogle's short term goal is to obtain a doctoral degree from the Immunology program at NCSU. Dr. Fogle's long term goal is to continue independent lentiviral research that draws from both his clinical veterinary medicine and doctoral research experience. Proposal: A significant fraction of untreated HIV+ patients (progressors) are characterized by CD4+ and CD8+ T cell immune dysfunction. HIV-specific CD8+ effector cells are induced during the acute stage infection, but become non-responsive or """"""""anergic"""""""" to antigenic stimulation shortly after induction. We propose that the CD8+ T cell immune dysfunction is the result of """"""""clonal anergy"""""""" induced by membrane-bound TGF-beta (mTGF-beta) on virus activated CD4+CD25+ T reg cells that engage TGF-betaRII on the target cell. This hypothesis cannot be addressed in human subjects but rather requires a well-characterized experimental AIDS lentivirus animal model such as FIV. SPF cats will be infected with the NCSU1 isolate of FIV, plasma and PBMC/LN cells will be collected at various times post infection and quantitated for virus burden by ELISA and Real Time-PCR. PBMC/LN will be phenotyped for surface receptors by flow cytometry, and for Foxp3 mRNA by RT-PCR. Treg cells will be assessed for suppressor function by CD4+CD25+ cell depletion and by incubating FACS purified CD4+CD25+ cells with ConA and rFIVgag-stimulated CD8+ T cells and measuring IFNgamma by ELISpot. Ab-blocking experiments will be designed to test the hypothesis that Treg cells from FIV-infected cats anergize CD8+ T cells via mTGF-beta signaling. Purified CD4+CD25+ cells +/- anti-TGF-beta and purified CD8+ cells +/- anti-TGF-betaRII will be co-cultured and Treg suppressor function analyzed by measuring IFNgamma by ELISpot. Critical elements in the TGFbeta/ TGF-betaRII signaling pathway leading to suppression of CD8+ cell function will be analyzed, including Smad 2/3 phosphorylation, up-regulation of Foxp3 and Smad 7, and suppression of IFNgamma mRNA production. HIV is currently estimated to infect more than 37 million people world wide. FIV is a well established animal model of HIV/AIDS. The results of these experiments will have implications on future therapeutic strategies against HIV and FIV, and contribute to our current understanding of Treg cell function.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Clinical Investigator Award (CIA) (K08)
Project #
5K08AI074445-02
Application #
7612722
Study Section
Acquired Immunodeficiency Syndrome Research Review Committee (AIDS)
Program Officer
Embry, Alan C
Project Start
2008-05-01
Project End
2013-04-30
Budget Start
2009-05-01
Budget End
2010-04-30
Support Year
2
Fiscal Year
2009
Total Cost
$112,050
Indirect Cost

  Institution

Name
North Carolina State University Raleigh
Department
Veterinary Sciences
Type
Schools of Veterinary Medicine
DUNS #
042092122
City
Raleigh
State
NC
Country
United States
Zip Code
27695

  Publications

Miller, Michelle M; Akaronu, Nnenna; Thompson, Elizabeth M et al. (2015) Modulating DNA methylation in activated CD8+ T cells inhibits regulatory T cell-induced binding of Foxp3 to the CD8+ T Cell IL-2 promoter. J Immunol 194:990-8
Meng, Liping; Tompkins, Mary; Miller, Michelle et al. (2014) Lentivirus-activated T regulatory cells suppress T helper cell interleukin-2 production by inhibiting nuclear factor of activated T cells 2 binding to the interleukin-2 promoter. AIDS Res Hum Retroviruses 30:58-66
Miller, Michelle M; Petty, Christopher S; Tompkins, Mary B et al. (2014) CD4+CD25+ T regulatory cells activated during feline immunodeficiency virus infection convert T helper cells into functional suppressors through a membrane-bound TGF? / GARP-mediated mechanism. Virol J 11:7
Miller, Michelle M; Fogle, Jonathan E; Tompkins, Mary B (2013) Infection with feline immunodeficiency virus directly activates CD4+ CD25+ T regulatory cells. J Virol 87:9373-8
Miller, Michelle M; Thompson, Elizabeth M; Suter, Steven E et al. (2013) CD8+ clonality is associated with prolonged acute plasma viremia and altered mRNA cytokine profiles during the course of feline immunodeficiency virus infection. Vet Immunol Immunopathol 152:200-8
Miller, Michelle M; Fogle, Jonathan E; Ross, Peter et al. (2013) Feline glycoprotein A repetitions predominant anchors transforming growth factor beta on the surface of activated CD4(+)CD25(+) regulatory T cells and mediates AIDS lentivirus-induced T cell immunodeficiency. AIDS Res Hum Retroviruses 29:641-51
Miller, Michelle M; Fogle, Jonathan E (2012) Administration of Fozivudine tidoxil as a single-agent therapeutic during acute feline immunodeficiency virus infection does not alter chronic infection. Viruses 4:954-62
Fogle, J E; Tompkins, W A; Campbell, B et al. (2011) Fozivudine tidoxil as single-agent therapy decreases plasma and cell-associated viremia during acute feline immunodeficiency virus infection. J Vet Intern Med 25:413-8
Fogle, Jonathan E; Mexas, Angela M; Tompkins, Wayne A et al. (2010) CD4(+)CD25(+) T regulatory cells inhibit CD8(+) IFN-gamma production during acute and chronic FIV infection utilizing a membrane TGF-beta-dependent mechanism. AIDS Res Hum Retroviruses 26:201-16
Fogle, Jonathan E; Tompkins, Wayne A; Tompkins, Mary B (2010) CD4+CD25+ T regulatory cells from FIV+ cats induce a unique anergic profile in CD8+ lymphocyte targets. Retrovirology 7:97