São Paulo, São Paulo, Brazil, Léia C. Rodrigues Silva, PhDStudent, Laboratory of Dermatology andImmunodeficiencies, Medical School of the University ofSão Paulo, São Paulo, Brazil, Guilherme G. Silveira,Student, Laboratory of Dermatology andImmunodeficiencies, Medical School of the University ofSão Paulo, São Paulo, Brazil, Maury M. Tanji, Laboratory ofDermatology and Immunodeficiencies, Medical School ofthe University of São Paulo, São Paulo, Brazil, DeniseSchout, Epidemiology Service, Hospital das Clínicas,Medical School of the University of São Paulo, São Paulo,Brazil, Alberto J.S. Duarte, Professor, Laboratory ofDermatology and Immunodeficiencies, Medical School ofthe University of São Paulo, São Paulo, Brazil

Background: The degree Mycobacterium tuberculosis (Mtb)immune reconstitution provided by long-term (N4 years)successful HAART and whether a past tuberculosis (TB) historyinfluences this reconstitution are not known. Methods: Wecompared the lymphocyte proliferative response (LPR) and IFN-ã secretion to phytohemagglutinin (PHA) and Mtb antigens(ESAT6, Ag85B and whole Mtb lysate [SMtb]) of immunerecon-stituted (CD4 N500 cells/ìl) HIV+ patients with a past history ofcured TB (HIV+ CTB group) or latent infection as presumed bypositive purified protein derivative skin test (PPD+) (HIV+ PPD+group) with HIV− controls either cured from TB (CTB group) orPPD reactors (PPD+ group). The databank on TB incidenceamong HIV+ and HIV− patients at our services during 1999–2005wasalso analyzed.Results:MostHIV+patients presentednormalPHA responses. However, Mtb immune reconstitution wasincomplete, especially to ESAT6 and Ag85B. SMtb reactivitywas fully restored in the HIV+ CTB group, while in HIV+ PPD+patients it remained lower than in PPD+ controls. Comparisonbetween the two HIV groups also suggested better immunereconstitution in HIV+ CTB patients. Databank analysis revealedthat some HIV+ patients with N360 CD4 cells/ìl still developedTB, but not those with previous TB history. Conclusions: Mtbimmune reconstitution is incomplete in HIV+ CTB and HIV+ PPD+ patients even after highly successful HAART. However,reactivity to whole mycobacteria antigens is restored,especially in HIV+ CTB patients, possibly due to survival ofhigher numbers of mycobacteria-specific Tcell clones through-out immunosuppression, probably allowing sufficient protec-tion against new Mtb challenges.

doi:10.1016/j.clim.2007.03.266

F.53 Human CD8+ Cytotoxic T Lymphocyte EpitopesIdentified from Herpes Simplex Virus Type 1Glycoprotein DAziz Alami Chentoufi, Assistant Specialist, Cellular andMolecular Immunology Laboratory, The Eye Institute,University of California, Irvine, Orange, CA, Xiuli Zhang,Postdoctoral Fellow, Cellular and Molecular ImmunologyLaboratory, The Eye Institute, University of California,Irvine, Orange, CA, Kasper Lamberth, Researcher, Instituteof Medical Microbiology and Immunology (IMMI), Universityof Copenhagen, 2200 Copenhagen, Denmark, Xiaoming Zhu,Research Associate, Cellular and Molecular ImmunologyLaboratory, The Eye Institute, University of California,

Irvine, Orange, CA, Gargi Dasgupta, Research Associate,Cellular and Molecular Immunology Laboratory, The EyeInstitute, University of California, Irvine, orange, CA,Michele Wu, Student, Cellular and Molecular ImmunologyLaboratory, The Eye Institute, University of California,Irvine, Orange, CA, Alex Nguyen, Bio-199 Student, Cellularand Molecular Immunology Laboratory, The Eye Institute,University of California, Irvine, Orange, CA, Ilham Bettahi,Postdoctoral Fellow, Cellular and Molecular ImmunologyLaboratory, The Eye Institute, University of California,Irvine, Orange, CA, Søren Buus, Professor, Institute ofMedical Microbiology and Immunology (IMMI), University ofCopenhagen, 2200 Copenhagen, Denmark, LbachirBenMohamed, Assistant Professor, Cellular and MolecularImmunology Laboratory, The Eye Institute, University ofCalifornia, Irvine, Orange, CA

Cytolystic Tcells (CTLs) play a major role in herpes simplexvirus type 1 and type 2 (HSV-1 and HSV-2) infections anddiseases. Among some eleven HSV-1 and HSV-2 coat glycopro-teins, glycoprotein D (gD) induces immunodominant Tcells andis a leading vaccine candidate antigen. However, little is knownabout human CD8+ T cell epitopes of gD. Based on predictivecomputational algorithms and peptide binding affinity to HLA-A*0201 molecules, we have identified ten regions within theHSV-1 gD, each 9 to 10 amino acids in length, exhibiting highaffinity CD8+Tcell epitope(s). T2 cell stabilization assay showedpeptide gD53-61, gD70-78 and gD278-286 significantly, and indose-dependent manner, upregulates HLA-A*0201 moleculesexpression. To obtain an objective enumeration of CD8+ Tcellsinduced by each gD peptide epitope, we employed the HLA-A*0201 tetramer staining procedure. A relatively high percen-tagesofCD8+Tcells positive for gD-18-10, gD53-61, gD70-78andgD278-286/HLA-A*0201 tetramers were detected in PBMC fromHLA-A*0201 seropositive patients, either directly ex vivo orfollowing a single in vitro stimulation. Accordingly, strong HLA-A*0201-restricted CD8+ CTLs, assessed by INF-γ-ELISPOT andCD107a/b cytotoxic assays, were mapped to gD53-61, gD70-78and gD278-286 peptides. However, only gD53-61 and gD278-286peptides were able to generate CD8+ T cells that recognizeinfected target cells. Collectively, these findings suggest thathigh-affinity HLA-A*0201-binding gD53-61 and gD278-286 epi-topes are naturally processed and are recognized by HSV-specific CD8+ CTLs in the infected human population, providingimportant information for the development of subunit vaccinestrategies against herpes.

doi:10.1016/j.clim.2007.03.267

F.55 Protection Against SEB-Induced Toxic Shock byAnti-TCR Vb8 AntibodyManisha Singh, Postdoctoral Associate, Baylor College ofMedicine, Immunology Department, Houston, TX

Intraperitoneal injection of the bacterial superantigen,Staphylococcus enterotoxin B (SEB) in HLA-DR3 transgenicmice leads to toxic shock and death within 72 h. In vivo,this is characterized by a marked expansion of splenic TCRVb8+ CD4 and CD8 T cells compared to PBS treated mice. It

S32 Abstracts