Medical Student Research Fellowship for Summer 2009

Mentor: Richard Koup, MD
Department: Immunology Laboratory, Vaccine Research Center, NIAID, National Institutes of Health
Room number: Building 40, Rm 3502, Bethesda, MD 20892
Phone number: 301-594-8585
E-mail: rkoup@mail.nih.gov

Project title: TCR Sequencing of HIV-specific CD8+ T cell Responses Induced by Therapeutic Vaccination in HIV-infected Individuals

Human subjects IRB approved project number (where applicable): 06-I-0056

Project Type Patient based Research

Brief Description of Project:

Background:
VRC101 is a therapeutic vaccine trial enrolling 17 HIV-infected men on effective HAART (viral loads < 50 copies/ml) utilizing a DNA plasmid prime, recombinant replication-deficient adenovirus 5 vector (rAd5) boost vaccine regimen. Vaccinees received 3 DNA plasmid priming vaccinations at one month intervals, followed by a rAd5 boost vaccination 6 months after initiation of the regimen. Vaccination was well-tolerated and vaccinees maintained undetectable viral loads throughout the trial. By analyzing the cellular immune response pre- and post-vaccination, this study looks at the ability of therapeutic vaccination to boost the magnitude, quality and breadth of the antigen-specific T lymphocyte response. Using flow cytometry and IFNg ELISpot assays, we measured an increase in both the frequency of responses of existing T cell clones, as well as an increase in the number of identifiable epitope-specific responses after vaccination.

Project description:
This summer, we will begin to sequence T cell receptors from VRC101. First, we will use MHC tetramers to isolate CD8+ T cells specific to optimized epitopes that were boosted by vaccination using fluorescence-associated cell sorting (FACS). We will then sequence the CDR3 region of these individual T cells. The CDR3 region is unique to each T cell clone, and is the region principally responsible for recognizing processed antigen. By sequencing pre- and post- vaccination T cell receptors, we hope to identify new T cell clones induced by vaccination.

Previous Research Activities or Publications with Medical Students:

1. Freel SA. Lamoreaux L. Chattopadhyay PK. Saunders K. Zarkowsky D*. Overman RG. Ochsenbauer C. Edmonds TG. Kappes JC. Cunningham CK. Denny TN. Weinhold KJ. Ferrari G. Haynes BF. Koup RA. Graham BS. Roederer M. Tomaras GD. (2010) Phenotypic and functional profile of HIV-inhibitory CD8 T cells elicited by natural infection and heterologous prime/boost vaccination. Journal of Virology. 84(10):4998-5006.

2. Casazza JP. Brenchley JM. Hill BJ. Ayana R*. Ambrozak D. Roederer M. Douek DC. Betts MR. Koup RA. (2009) Autocrine production of beta-chemokines protects CMV-Specific CD4 T cells from HIV infection. PLoS Pathogens. 5(10):e1000646.

3. Petrovas C. Chaon B*. Ambrozak DR. Price DA. Melenhorst JJ. Hill BJ. Geldmacher C. Casazza JP. Chattopadhyay PK. Roederer M. Douek DC. Mueller YM. Jacobson JM. Kulkarni V. Felber BK. Pavlakis GN. Katsikis PD. Koup RA. (2009) Differential association of programmed death-1 and CD57 with ex vivo survival of CD8+ T cells in HIV infection. Journal of Immunology. 183(2):1120-32.

4. Precopio ML. Butterfield TR*. Casazza JP. Little SJ. Richman DD. Koup RA. Roederer M. (2008) Optimizing peptide matrices for identifying T-cell antigens. Cytometry Part A: The Journal of the International Society for Analytical Cytology. 73(11):1071-8.

5. Duvall MG*. Precopio ML. Ambrozak DA. Jaye A. McMichael AJ. Whittle HC. Roederer M. Rowland-Jones SL. Koup RA. Polyfunctional T cell responses are a hallmark of HIV-2 infection. (2008) European Journal of Immunology. 38(2):350-63.

6. Duvall MG*. Lore K. Blaak H. Ambrozak DA. Adams WC. Santos K. Geldmacher C. Mascola JR. McMichael AJ. Jaye A. Whittle HC. Rowland-Jones SL. Koup RA. (2007) Dendritic cells are less susceptible to human immunodeficiency virus type 2 (HIV-2) infection than to HIV-1 infection. Journal of Virology. 81(24):13486-9.

7. Beveridge NE*. Price DA. Casazza JP. Pathan AA. Sander CR. Asher TE. Ambrozak DR. Precopio ML. Scheinberg P. Alder NC. Roederer M. Koup RA. Douek DC. Hill AV. McShane H. (2007) Immunisation with BCG and recombinant MVA85A induces long-lasting, polyfunctional Mycobacterium tuberculosis-specific CD4+ memory T lymphocyte populations. European Journal of Immunology. 37(11):3089-100.

8. Price DA. West SM*. Betts MR. Ruff LE. Brenchley JM. Ambrozak DR. Edghill-Smith Y. Kuroda MJ. Bogdan D. Kunstman K. Letvin NL. Franchini G. Wolinsky SM. Koup RA. Douek DC. (2004) T cell receptor recognition motifs govern immune escape patterns in acute SIV infection. Immunity. 21(6):793-803.

* Denotes medical student