Direct Recovery of Herpes Simplex Virus (HSV)-Specific T Lymphocyte Clones from Recurrent Genital HSV-2 Lesions

NK cells infiltrate human herpetic lesions, but their role has been underexplored. HSV can stimulate innate immune responses via surface TLR2, which is expressed on monocyte-derived dendritic cells (DCs) and NK cells. In this study, UV-inactivated HSV1/2 and immunodominant HSV2 glycoprotein D peptides conjugated to the TLR2 agonist dipalmitoyl-S-glyceryl cysteine stimulated CD4 T lymphocyte IFN-γ responses within PBMCs or in coculture with monocyte-derived DCs. NK cells contributed markedly to the PBMC responses. Furthermore, NK cells alone were activated directly by both Ags, also upregulating HLA-DR and HLA-DQ and then they activated autologous CD4 T lymphocytes. Using Transwells, Ag-stimulated NK cells and CD4 T lymphocytes were shown to interact through both cell-to-cell contact and cytokines, differing in relative importance in different donors. A distinct immunological synapse between Ag-stimulated NK cells and CD4 T lymphocytes was observed, indicating the significance of their cell-to-cell contact. A large proportion (57%) of NK cells was also in contact with CD4 T lymphocytes in the dermal infiltrate of human recurrent herpetic lesions. Thus, NK cells stimulated by TLR2-activating HSV Ags can present Ag alone or augment the role of DCs in vitro and perhaps in herpetic lesions or draining lymph nodes. In addition to DCs, NK cells should be considered as targets for adjuvants during HSV vaccine development.

Section: Discussionsupporting

confidence: 90%

Herpes Simplex Virus Antigens Directly Activate NK Cells via TLR2, Thus Facilitating Their Presentation to CD4 T Lymphocytes

Kim

Osborne

Zeng

et al. 2012

“…Lesion-infiltrating T cells were expanded in bulk from vesicle fluid or punch biopsy of HSV-2 culture-positive lesions with 0.8 g/ml PHA-P (Murex Diagnostics, Dartford, U.K.), 32 U/ml IL-2 (Schiaperelli Biosystems, Columbia, MD), allogeneic irradiated PBMC, and 50 M acyclovir (5). CD8 ϩ T cells were positively selected using CD8 microbeads and MiniMACS columns (Miltenyi Biotec, Auburn, CA) from bulk lesion cultures containing CD8 ϩ T cells (as determined by flow cytometry) and with cytotoxic activity (as determined by a standard 51 Cr release assay).…”

Section: Lesion-derived Hsv-specific Cd8 ϩ Ctl Clonesmentioning

confidence: 99%

“…High frequencies of HSV-specific CD4 ϩ and CD8 ϩ T cell precursors are present in PBMC from immunocompetent HSVseropositive individuals (3,4), and both cell types infiltrate herpetic lesions (5,6). In cross-sectional studies, immunosuppressed individuals with severe genital herpes infections (frequent and long-lasting lesions) had significantly lower frequencies of HSVspecific CD8 ϩ CTL precursors than did individuals with mild disease (7).…”

mentioning

confidence: 99%

Long Term Persistence of Herpes Simplex Virus-Specific CD8+ CTL in Persons with Frequently Recurring Genital Herpes

Posavad

Huang²,

Barcy³

et al. 2000

Self Cite

Herpes simplex virus (HSV) establishes a lifelong infection in humans. Reactivation of latent virus occurs intermittently so that the immune system is frequently exposed to viral Ag, providing an opportunity to evaluate memory T cells to a persistent human pathogen. We studied the persistence of genital herpes lesion-derived HSV-specific CD8+ CTL from three immunocompetent individuals with frequently recurring genital HSV-2 infection. All CTL clones were HSV-2 type specific and only one to three unique clonotypes were identified from any single biopsy specimen. The TCRBV genes utilized by these clonotypes were sequenced, and clonotype-specific probes were used to longitudinally track these clonotypes in PBMC and genital lesions. CTL clonotypes were consistently detected in PBMC and lesions for at least 2 and up to 7 years, and identical clonotypes infiltrated herpes lesions spaced as long as 7.5 years apart. Moreover, these clones were functionally lytic in vivo over these time periods. Additionally, CTL clones killed target cells infected with autologous viral isolates obtained 6.5 years after CTL clones were established, suggesting that selective pressure by these CTL did not result in the mutation of CTL epitopes. Thus, HSV recurs in the face of persistent CD8+ CTL with no evidence of clonal exhaustion or mutation of CTL epitopes as mechanisms of viral persistence.

“…CD8 CTL localize to the site of recurrent HSV-2 genital lesions (10,11), and the clearance of infectious virus from lesions correlates temporally with the infiltration of CD8 T cells and HSV-specific CTL (12). In HIV-HSV-2-coinfected subjects, the frequency of HSV-specific CD8 CTL in the PBMC correlated inversely with the severity of recurrent anogenital HSV-2 infection in a cross-sectional study (13).…”

mentioning

confidence: 99%

CD8 CTL from Genital Herpes Simplex Lesions: Recognition of Viral Tegument and Immediate Early Proteins and Lysis of Infected Cutaneous Cells

Koelle

Chen

Gavin

et al. 2001

Self Cite

116

173

HSV-2 causes chronic infections. CD8 CTL may play several protective roles, and stimulation of a CD8 response is a rational element of vaccine design for this pathogen. The viral Ags recognized by CD8 T cells are largely unknown. It has been hypothesized that HSV inhibition of TAP may favor recognition of virion input proteins or viral immediate early proteins. We tested this prediction using HSV-specific CD8 CTL clones obtained from genital HSV-2 lesions. Drug and replication block experiments were consistent with specificity for the above-named classes of viral proteins. Fine specificity was determined by expression cloning using molecular libraries of viral DNA, and peptide epitopes recognized at nanomolar concentrations were identified. Three of four clones recognized the viral tegument proteins encoded by genes UL47 and UL49. These proteins are transferred into the cytoplasm on virus entry. Processing of the tegument Ag-derived epitopes was TAP dependent. The tegument-specific CTL were able to lyse HLA class I-appropriate fibroblasts after short times of infection. Lysis of keratinocytes required longer infection and pretreatment with IFN-γ. Another clone recognized an immediate early protein, ICP0. Lymphocytes specific for these lesion-defined epitopes could be reactivated from the PBMC of additional subjects. These data are consistent with an influence of HSV immune evasion genes upon the selection of proteins recognized by CD8 CTL in lesions. Tegument proteins, identified for the first time as Ags recognized by HSV-specific CD8 CTL, are rational candidate vaccine compounds.