Sample records for cd8 positive cells

  1. Canine CD4(+)CD8(+) double-positive T cells can develop from CD4(+) and CD8(+) T cells.

    Bismarck, Doris; Moore, Peter F; Alber, Gottfried; von Buttlar, Heiner


    For a long time the expression of the CD4 and CD8 receptor on peripheral blood T cells was thought to be mutually exclusive. However, in canine peripheral blood, similar to other species as swine or human for example, mature CD4(+)CD8(+) double-positive (dp) T cells exist which simultaneously express both surface receptors and have features of activated T cells. Canine CD4(+)CD8(+)dp T cells are heterogeneous and can be divided into three subpopulations by their intensity of CD4 and CD8α expression: CD4(bright)CD8α(bright), CD4(dim)CD8α(bright) and CD4(dim)CD8α(dim). The number of CD4(+)CD8α(+)dp T cells increases after in vitro stimulation of canine peripheral blood mononuclear cells (PBMC) raising the question of their progenitor(s). Thus, the aim of our study was to characterize the progenitor(s) of canine CD4(+)CD8α(+)dp T cells. By cell tracing experiments we identified both CD4(+) single-positive (sp) and also CD8α(+)sp T cells as progenitors of canine CD4(+)CD8α(+)dp T cells after in vitro stimulation. CD4(+)sp T cells almost exclusively upregulate a CD8αα homodimer, whereas CD8α(+)sp T cells can become CD4(+)CD8αβ(+) or CD4(+)CD8αα(+). Even in the absence of other cells, highly purified CD4(+)sp T cells can become double-positive upon in vitro stimulation, whereas highly purified CD8α(+)sp T cells fail to do so. However, CD8α(+)sp T cells can additionally express CD4 when stimulated in the presence of CD4(-)CD8α(-) double-negative (dn) cells or more efficiently when stimulated in the presence of CD4(+)sp T cells. Soluble factors secreted by CD4(+)sp T cells are sufficient for the upregulation of CD4 on CD8α(+)sp T cells, but direct cell-cell contact between CD4(+)sp and CD8α(+)sp T cells is more efficient. mRNA analysis shows that additional CD4 expression on CD8α(+)sp T cells results from de novo synthesis. Thus, uptake of soluble CD4 or trogocytosis is less likely as mechanism for generation of canine double-positive T cells. CD4(+)CD

  2. CD4+/CD8+ double-positive T cells

    Overgaard, Nana H; Jung, Ji-Won; Steptoe, Raymond J;


    lymphoid tissues of numerous species, as well as in numerous disease settings, including cancer. The expression of CD4 and CD8 is regulated by a very strict transcriptional program involving the transcription factors Runx3 and ThPOK. Initially thought to be mutually exclusive within CD4(+) and CD8(+) T...... reports describing cytotoxic or suppressive roles for these cells. In this review, we describe how transcriptional regulation, lineage of origin, heterogeneity of CD4 and CD8 expression, age, species, and specific disease settings influence the functionality of this rarely studied T cell population....

  3. Tuberculosis-specific CD8 cells in HLA A*02-positive TB- and LTBI patients

    Fløe, Andreas; Brix, Liselotte; Wejse, Christian;

    Background: Understanding the CD8+ response against Mycobacterium tuberculosis (MTB) may be a key to improved TB diagnostics and vaccine development. Aims and Objectives: To detect a CD8+ T-cell response against Mycobacterium tuberculosis (MTB) in active tuberculosis (TB) and latent TB (LTBI), in...... candidates, from which we constructed MHC multimers (Dextramers). Peripheral blood mononuclear cells (PBMC) from 7 TB-patients, 16 LTBI patients and 8 MTB-exposed, IGRA-negative, healthy subjects (HE), all HLA A*02 positive, were stained with the Dextramers and with anti-CD8 and anti-CD3, and analyzed on a...... flow cytometer. The MTB epitopes were analyzed in 5 pools (3-7 epitopes each). Positive responses included >0.001 % of CD8+, CD3+ cells, supported by inspection of flow cytometry plots. Results: MTB-specific CD8+ T-cells were detected more often in TB patients (57%) than in LTBI patients (41%) and in...

  4. Canine CD4+CD8+ double positive T cells in peripheral blood have features of activated T cells.

    Bismarck, Doris; Schütze, Nicole; Moore, Peter; Büttner, Mathias; Alber, Gottfried; Buttlar, Heiner v


    In dogs a CD4(+)CD8(+) double positive T cell subpopulation exists that has not been phenotypically defined yet. We demonstrate that canine CD4(+)CD8(+) T cells are mature CD1a(-) and TCRαβ(+) T cells. To analyse the activation potential of CD4(+)CD8(+) T cells, PBMC from dogs vaccinated against canine distemper virus (CDV) were re-stimulated with CDV. Upon antigen-specific stimulation, the CD4(+)CD8(+) T cell fraction increases and consists nearly exclusively of proliferated cells. Similarly, other features of activated effector/memory T cells such as up-regulation of CD25 and MHC-II as well as down-regulation of CD62L (L-selectin) were observed in CD4(+)CD8(+) T cells after stimulation. Canine CD4(+)CD8(+) T cells are less abundant, but more heterogeneous than porcine ones, comprising a small proportion expressing the β chain of CD8 in addition to the CD8α chain, like human CD4(+)CD8(+) T cells. In summary, this analysis provides the basis for functional characterisation of the in vivo relevance of CD4(+)CD8(+) T cells in T-cell mediated immunity. PMID:22789871

  5. CD8 positive T cells express IL-17 in patients with chronic obstructive pulmonary disease

    Eidelman David H


    Full Text Available Abstract Background Chronic obstructive pulmonary disease (COPD is a progressive and irreversible chronic inflammatory disease of the lung. The nature of the immune reaction in COPD raises the possibility that IL-17 and related cytokines may contribute to this disorder. This study analyzed the expression of IL-17A and IL-17F as well as the phenotype of cells producing them in bronchial biopsies from COPD patients. Methods Bronchoscopic biopsies of the airway were obtained from 16 COPD subjects (GOLD stage 1-4 and 15 control subjects. Paraffin sections were used for the investigation of IL-17A and IL-17F expression in the airways by immunohistochemistry, and frozen sections were used for the immunofluorescence double staining of IL-17A or IL-17F paired with CD4 or CD8. In order to confirm the expression of IL-17A and IL-17F at the mRNA level, a quantitative RT-PCR was performed on the total mRNA extracted from entire section or CD8 positive cells selected by laser capture microdissection. Results IL-17F immunoreactivity was significantly higher in the bronchial biopsies of COPD patients compared to control subjects (P P P P Conclusion These findings support the notion that Th17 cytokines could play important roles in the pathogenesis of COPD, raising the possibility of using this mechanism as the basis for novel therapeutic approaches.

  6. Structural Basis of the CD8[alpha beta]/MHC Class I Interaction: Focused Recognition Orients CD8[beta] to a T Cell Proximal Position[superscript 1,2

    Wang, Rui; Natarajan, Kannan; Margulies, David H.; (NIH)


    In the immune system, B cells, dendritic cells, NK cells, and T lymphocytes all respond to signals received via ligand binding to receptors and coreceptors. Although the specificity of T cell recognition is determined by the interaction of T cell receptors with MHC/peptide complexes, the development of T cells in the thymus and their sensitivity to Ag are also dependent on coreceptor molecules CD8 (for MHC class I (MHCI)) and CD4 (for MHCII). The CD8{alpha}{beta} heterodimer is a potent coreceptor for T cell activation, but efforts to understand its function fully have been hampered by ignorance of the structural details of its interactions with MHCI. In this study we describe the structure of CD8{alpha}{beta} in complex with the murine MHCI molecule H-2D{sup d} at 2.6 {angstrom} resolution. The focus of the CD8{alpha}{beta} interaction is the acidic loop (residues 222-228) of the {alpha}3 domain of H-2D{sup d}. The {beta} subunit occupies a T cell membrane proximal position, defining the relative positions of the CD8{alpha} and CD8{beta} subunits. Unlike the CD8{alpha}{alpha} homodimer, CD8{alpha}{beta} does not contact the MHCI {alpha}{sub 2}- or {beta}{sub 2}-microglobulin domains. Movements of the CD8{alpha} CDR2 and CD8{beta} CDR1 and CDR2 loops as well as the flexibility of the H-2D{sup d} CD loop facilitate the monovalent interaction. The structure resolves inconclusive data on the topology of the CD8{alpha}{beta}/MHCI interaction, indicates that CD8{beta} is crucial in orienting the CD8{alpha}{beta} heterodimer, provides a framework for understanding the mechanistic role of CD8{alpha}{beta} in lymphoid cell signaling, and offers a tangible context for design of structurally altered coreceptors for tumor and viral immunotherapy.

  7. File list: Unc.Bld.20.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available Unc.Bld.20.AllAg.CD4_CD8_double_positive_cells mm9 Unclassified Blood CD4 CD8 double positive... cells SRX199993 ...

  8. File list: DNS.Bld.20.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available DNS.Bld.20.AllAg.CD4_CD8_double_positive_cells mm9 DNase-seq Blood CD4 CD8 double positive... cells ...

  9. File list: DNS.Bld.50.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available DNS.Bld.50.AllAg.CD4_CD8_double_positive_cells mm9 DNase-seq Blood CD4 CD8 double positive... cells ...

  10. File list: NoD.Bld.10.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available NoD.Bld.10.AllAg.CD4_CD8_double_positive_cells mm9 No description Blood CD4 CD8 double positive... cells ...

  11. File list: Pol.Bld.10.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available Pol.Bld.10.AllAg.CD4_CD8_double_positive_cells mm9 RNA polymerase Blood CD4 CD8 double positive... cells SRX063926,SRX099388,SRX099398 ...

  12. File list: Unc.Bld.05.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available Unc.Bld.05.AllAg.CD4_CD8_double_positive_cells mm9 Unclassified Blood CD4 CD8 double positive... cells SRX199993 ...

  13. File list: DNS.Bld.10.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available DNS.Bld.10.AllAg.CD4_CD8_double_positive_cells mm9 DNase-seq Blood CD4 CD8 double positive... cells ...

  14. File list: NoD.Bld.20.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available NoD.Bld.20.AllAg.CD4_CD8_double_positive_cells mm9 No description Blood CD4 CD8 double positive... cells ...

  15. File list: NoD.Bld.05.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available NoD.Bld.05.AllAg.CD4_CD8_double_positive_cells mm9 No description Blood CD4 CD8 double positive... cells ...

  16. File list: Unc.Bld.10.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available Unc.Bld.10.AllAg.CD4_CD8_double_positive_cells mm9 Unclassified Blood CD4 CD8 double positive... cells SRX199993 ...

  17. File list: Pol.Bld.20.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available Pol.Bld.20.AllAg.CD4_CD8_double_positive_cells mm9 RNA polymerase Blood CD4 CD8 double positive... cells SRX063926,SRX099398,SRX099388 ...

  18. File list: Unc.Bld.50.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available Unc.Bld.50.AllAg.CD4_CD8_double_positive_cells mm9 Unclassified Blood CD4 CD8 double positive... cells SRX199993 ...

  19. File list: Pol.Bld.05.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available Pol.Bld.05.AllAg.CD4_CD8_double_positive_cells mm9 RNA polymerase Blood CD4 CD8 double positive... cells SRX063926,SRX099388,SRX099398 ...

  20. File list: DNS.Bld.05.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available DNS.Bld.05.AllAg.CD4_CD8_double_positive_cells mm9 DNase-seq Blood CD4 CD8 double positive... cells ...

  1. File list: His.Bld.50.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available His.Bld.50.AllAg.CD4_CD8_double_positive_cells mm9 Histone Blood CD4 CD8 double ...

  2. File list: His.Bld.05.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available His.Bld.05.AllAg.CD4_CD8_double_positive_cells mm9 Histone Blood CD4 CD8 double ...

  3. File list: ALL.Bld.50.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available ALL.Bld.50.AllAg.CD4_CD8_double_positive_cells mm9 All antigens Blood CD4 CD8 double positive...X018116,SRX018113 ...

  4. File list: ALL.Bld.10.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available ALL.Bld.10.AllAg.CD4_CD8_double_positive_cells mm9 All antigens Blood CD4 CD8 double positive...X099392,SRX018112 ...

  5. File list: His.Bld.20.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available His.Bld.20.AllAg.CD4_CD8_double_positive_cells mm9 Histone Blood CD4 CD8 double ...

  6. File list: ALL.Bld.20.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available ALL.Bld.20.AllAg.CD4_CD8_double_positive_cells mm9 All antigens Blood CD4 CD8 double positive...X018116,SRX018113 ...

  7. File list: His.Bld.10.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available His.Bld.10.AllAg.CD4_CD8_double_positive_cells mm9 Histone Blood CD4 CD8 double ...

  8. File list: ALL.Bld.05.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available ALL.Bld.05.AllAg.CD4_CD8_double_positive_cells mm9 All antigens Blood CD4 CD8 double positive...X692962,SRX692956 ...

  9. Peripheral blood TIM-3 positive NK and CD8+ T cells throughout pregnancy

    Meggyes, Matyas; Miko, Eva; Polgar, Beata;


    negative regulator of Th1 immunity and tolerance induction. Data about the TIM-3/Gal-9 pathway in the pathogenesis of human diseases is emerging, but their possible role during human pregnancy is not precisely known. The aim of our study was to investigate the number, phenotype and functional activity of...... TIM-3+ peripheral blood mononuclear cells during healthy human pregnancy. METHODS OF STUDY: 57 healthy pregnant women [first trimester (n = 16); second trimester (n = 19); third trimester (n = 22)] and 30 non-pregnant controls were enrolled in the study. We measured the surface expression of TIM-3 by...... cytotoxic T cells, NK cells and NK cell subsets as well as Galectin-9 expression by regulatory T cells by flow cytometry. We analyzed the cytokine production and cytotoxicity of TIM3+ and TIM3- CD8 T and NK cells obtained from non-pregnant and healthy pregnant women at different stages of pregnancy by flow...

  10. File list: Oth.Bld.10.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available Oth.Bld.10.AllAg.CD4_CD8_double_positive_cells mm9 TFs and others Blood CD4 CD8 double positive...80,SRX091675,SRX063930,SRX018102,SRX063928 ...

  11. File list: Oth.Bld.05.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available Oth.Bld.05.AllAg.CD4_CD8_double_positive_cells mm9 TFs and others Blood CD4 CD8 double positive...32,SRX099383,SRX063930,SRX091675,SRX099380 ...

  12. File list: InP.Bld.50.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available InP.Bld.50.AllAg.CD4_CD8_double_positive_cells mm9 Input control Blood CD4 CD8 double positive...SRX091683,SRX700943,SRX700944,SRX700945,SRX700942,SRX692962,SRX099379 ...

  13. File list: Oth.Bld.50.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available Oth.Bld.50.AllAg.CD4_CD8_double_positive_cells mm9 TFs and others Blood CD4 CD8 double positive...49,SRX063930,SRX099378,SRX063928,SRX091675 ...

  14. File list: InP.Bld.05.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available InP.Bld.05.AllAg.CD4_CD8_double_positive_cells mm9 Input control Blood CD4 CD8 double positive...SRX692947,SRX091683,SRX099381,SRX692948,SRX692963,SRX320065,SRX692962 ...

  15. File list: InP.Bld.20.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available InP.Bld.20.AllAg.CD4_CD8_double_positive_cells mm9 Input control Blood CD4 CD8 double positive...SRX320065,SRX692963,SRX099379,SRX700942,SRX700945,SRX700943,SRX692962 ...

  16. File list: InP.Bld.10.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available InP.Bld.10.AllAg.CD4_CD8_double_positive_cells mm9 Input control Blood CD4 CD8 double positive...SRX099393,SRX099381,SRX692963,SRX099379,SRX320065,SRX091683,SRX692962 ...

  17. File list: Oth.Bld.20.AllAg.CD4_CD8_double_positive_cells [Chip-atlas[Archive

    Full Text Available Oth.Bld.20.AllAg.CD4_CD8_double_positive_cells mm9 TFs and others Blood CD4 CD8 double positive...28,SRX018102,SRX063930,SRX091675,SRX063928 ...

  18. A highly restricted T-cell receptor dominates the CD8+ T-cell response to parvovirus B19 infection in HLA-A*2402-positive individuals

    Kasprowicz, V; Jeffery, K; Broliden, K;


    Six of seven HLA-A*2402-positive individuals with acute parvovirus B19 infections made vigorous CD8-positive cytotoxic T-cell (CTL) responses to the viral epitope FYTPLADQF. All responders showed highly focused T-cell receptor (TCR) usage, using almost exclusively BV5.1. The BV5.1 TCR dominated the...

  19. Double positive CD4+CD8+ T cells: key suppressive role in the production of autoantibodies in systemic lupus erythematosus

    Yongkang Wu


    Full Text Available Background & objectives: The presence of CD4+CD8+ (double positive T cells (DPT in the target organs of several autoimmune diseases has been reported. The aim of this study was to investigate the pathogenic role of DPT in systemic lupus erythematosus (SLE. Methods: A total of 175 SLE cases and 125 matched healthy controls were investigated for CD3+, CD4+, CD8+ lymphocytes and DPT by flow cytometry. Serum samples from SLE patients and controls were tested for antinuclear antibody (ANA, anti-double strain deoxyribonucleic acid (anti-dsDNA, anti-U1 ribonucleoprotein (anti-U1 RNP, anti-sjogren syndrome A (anti-SSA, anti-ribosomal P protein (anti-rib-P, anti-Smith (anti-Sm, anti-Sjogren syndrome B (anti-SSB, complement 3 (C3 and complement 4 (C4. Results: The DPT median and 5-95 per cent range of SLE cases and healthy controls were 0.50 [0.10-2.60] and 0.80 [0.20-2.74] respectively (P<0.001. SLE patients were divided into a ≥1:1000 subgroup and a <1:1000 subgroup according to the ANA titre. The DPT of the former subgroup was significantly lower than that of the latter (P=0.032. The DPT medians of positive subgroups with anti-dsDNA (P<0.001, anti-U1RNP (P=0.018, anti-SSA (P=0.021 or anti-rib-P (P=0.039 were also significantly lower than the negative subgroups. Likewise, DPT was significantly lower in SLE subgroups with low concentration of C3 or C4 than those with high concentration (P<0.006. Interpretation & conclusions: Our findings show that the DPT cells may play a key suppressive role in the production of autoantibodies in SLE. Direct evidence that DPT regulates the pathogenesis of SLE needs to be investigated in future work.

  20. In situ localisation of major histocompatibility complex class I and class II and CD8 positive cells in infectious salmon anaemia virus (ISAV)-infected Atlantic salmon

    Hetland, Dyveke Lem; Jørgensen, Sven Martin; Skjødt, Karsten;


    the early viraemia of ISAV was undertaken. Immunohistochemical investigations of spleen, head kidney and gills using monoclonal antibodies against recombinant proteins from MHC I, II and CD8 were performed on tissues from Atlantic salmon collected day 17 post-challenge in a cohabitant infection model...... MHC I, MHC II and CD8 positive cell populations differed between control salmon and cohabitant salmon in the early stages of ISAV infection. The changes in MHC I labelled cells differed between organs in ISAV cohabitants but all investigated organs showed a decreased presence of MHC II labelled cells...

  1. Enforced expression of GATA-3 during T cell development inhibits maturation of CD8 single-positive cells and induces thymic lymphoma in transgenic mice

    Nawijn, Martijn,; Ferreira, Rita; Dingjan, Gemma; Kahre, O; Drabek, Dubravka; Karis, Alar; Hendriks, Rudi; Grosveld, Frank


    textabstractThe zinc finger transcription factor GATA-3 is of critical importance for early T cell development and commitment of Th2 cells. To study the role of GATA-3 in early T cell development, we analyzed and modified GATA-3 expression in vivo. In mice carrying a targeted insertion of a lacZ reporter on one allele, we found that GATA-3 transcription in CD4(+)CD8(+) double-positive thymocytes correlated with the onset of positive selection events, i.e., TCRalphabeta up-regulation and CD69 ...

  2. Cytofluorographic and molecular identification of a CD8-positive, TCR-α/β-negative intraocular T cell lymphoma: a case report and review of the literature

    Saenz Alvaro D


    Full Text Available Abstract Introduction Cytofluorographic and molecular techniques are effective adjuncts in diagnosing intraocular lymphoma. Primary intraocular lymphoma is an uncommon entity predominantly of B cell origin and rarely with a T cell phenotype. The aim of the present paper is to report a case of a CD8-positive, TCR-α/β-negative intraocular T cell lymphoma and review the literature. Case presentation T cell neoplasia was detected based on flow cytometric demonstration of an abnormal T cell population and polymerase chain reactions for immunoglobulin and T-cell receptor rearrangements demonstrating evidence of monoclonality. Flow cytometry revealed a T cell population aberrantly expressing T-cell lineage markers. This T cell population expressed CD2, bright CD3, CD8, bright CD7, CD38, CD69, and variable CD25. T-cell receptor γ gene rearrangement studies demonstrated evidence of T-cell gene rearrangement confirming that the T cells were monoclonal. Conclusion We herein report the rare case of a TCR α/β-negative CD8+ intraocular T-cell lymphoma suggestive of gamma/delta origin diagnosed by flow cytometry and polymerase chain reaction.

  3. Dual-Positive (CD4+/CD8+ Acute Adult T-Cell Leukemia/Lymphoma Associated with Complex Karyotype and Refractory Hypercalcemia: Case Report and Literature Review

    Shahzad Raza


    Full Text Available We describe a rare case of adult T-cell leukemia characterized by an expansion of CD4+ CD8+ double-positive lymphocytes associated with human T-lymphotropic virus type 1 (HTLV-1 and a complex karyotype in a 43-year-old Caribbean male who was initially admitted to our hospital with significant lethargy, visual disturbances, dysphagia, right facial palsy and numbness in both feet for 3 days. He was found to have severe hypercalcemia (15.6 mg/dl. Peripheral blood smear showed multilobulated clover-shaped nuclei. Bone marrow and CSF flow cytometries revealed abnormal monoclonal expansion of T cells positive for CD4, CD5, CD8 and CD25 but negative for CD7, CD20, CD56, CD68 and terminal deoxynucleotidyl transferase. The polymerase chain reaction analysis showed a distinct band of the T-cell receptor γ gene, revealing T-cell clonal integration of the proviral DNA of HTLV-1, thus confirming the diagnosis of acute adult T-cell leukemia/lymphoma. Cytogenetic study revealed a male karyotype with monosomy 12, unbalanced translocation 5q and 13q and additional material on 5q, 7q, 14q and 17q. The patient underwent prednisone (EPOCH chemotherapy followed by autologous transplantation with BEAM regimen. Although patients with a rare mixed CD4+ CD8+ immunophenotype usually present with an aggressive clinical course and have a poor prognosis, our patient was able to survive for 2.5 years.

  4. Radiosensitivity of CD3-CD8+CD56+ NK cells

    Vokurkova, Doris [Charles University in Prague, Faculty of Medicine in Hradec Kralove, Department of Medical Biochemistry, Simkova 870, 50038 Hradec Kralove 1 (Czech Republic); Vavrova, Jirina [University of Defence, Faculty of Military Health Sciences, Department of Radiobiology, Hradec Kralove (Czech Republic); Sinkora, Jiri [Becton Dickinson (Czech Republic); Stoklasova, Alena [Charles University in Prague, Faculty of Medicine in Hradec Kralove, Department of Medical Biochemistry, Simkova 870, 50038 Hradec Kralove 1 (Czech Republic); Blaha, Vaclav [University of Defence, Faculty of Military Health Sciences, Department of Radiobiology, Hradec Kralove (Czech Republic); Rezacova, Martina, E-mail: rezacovam@lfhk.cuni.c [Charles University in Prague, Faculty of Medicine in Hradec Kralove, Department of Medical Biochemistry, Simkova 870, 50038 Hradec Kralove 1 (Czech Republic)


    The effect of lower doses (0.5-3.0 Gy) of gamma radiation on radiosensitivity of CD3-/CD8+ NK cells subpopulation isolated from the peripheral blood of healthy volunteers was studied 48 h after the irradiation. Only a subtle increase in terms of induction of apoptosis (A+ cells), was observed in Annexin positive CD3-/CD8+ NK cells. The assessment of the relative presence of CD3{sup -}/CD8{sup +} NK cells in Annexin negative populations of lymphocytes considerably contributes to the elimination of individual variability and could be useful in biodosimetry. Living CD3-/CD8+; Annexin negative NK cells were analyzed using five-color flow cytometry 16 h after irradiation by the doses of 1-10 Gy. The study was carried out on NK cells subsets CD3-/CD8- CD16+, CD56 (dim) and CD56 (bright). NK cells characterized with their low-density expression of CD56 (dim) are more cytotoxic and express CD16. Those with high-density expression of CD56 (bright) are known for their capacity to produce cytokines following activation of monocytes but their natural cytotoxicity is low; they are classified as CD16- or CD16 (dim). A dose-depending decrease in the relative presence of CD3-/CD8+ NK cells was observed 16 h after ionizing radiation (1-10 Gy). The decrease was highly pronounced in CD56 (bright) subset of NK cells and this subpopulation was considered as the most radiosensitive one. Unfortunately, the most radiosensitive subpopulation of NK cells - CD56bright cannot be used as a biodosimetric marker due to its insufficient amount in peripheral blood.

  5. Targeting CD8 T-Cell Metabolism in Transplantation

    Yap, Michelle; Brouard, Sophie; Pecqueur, Claire; Degauque, Nicolas


    Infiltration of effector CD8 T cells plays a major role in allograft rejection, and increases in memory and terminally differentiated effector memory CD8 T cells are associated with long-term allograft dysfunction. Alternatively, CD8 regulatory T cells suppress the inflammatory responses of effector lymphocytes and induce allograft tolerance in animal models. Recently, there has been a renewed interest in the field of immunometabolics and its important role in CD8 function and differentiation...

  6. The expression of CD8α discriminates distinct T cell subsets in teleost fish.

    Takizawa, Fumio; Dijkstra, Johannes Martinus; Kotterba, Paul; Korytář, Tomáš; Kock, Holger; Köllner, Bernd; Jaureguiberry, Beltran; Nakanishi, Teruyuki; Fischer, Uwe


    CD8, belonging to the TCR complex, is the main marker molecule of CTLs. Although CD8 genes have been detected in many fish species, the analysis of teleost CD8+ cells has been limited because of the lack of antibodies. Using newly established mAbs against rainbow trout CD8α, we found high ratios of CD8α+ cells in trout thymus, gill and intestine, but relatively low abundance in pronephros, spleen and blood. Accordingly, tissue sections revealed many CD8α+ cells in thymus, numerous intra- and subepithelial CD8α+ cells in intestine and gill and few scattered CD8α+ cells in spleen and pronephros. In secondary lymphoid tissues, CD8α+ lymphocytes, which did not react with anti-thrombocyte or anti-IgM mAbs, expressed CD8α, CD8β and TCRα, while Ig and CD4 transcripts were found in CD8α⁻ lymphocytes. In contrast, considerable CD4 expression in CD8α+ thymocytes suggests the presence of double-positive early T cells. Highly expressed TCRγ, LAG3 and CTLA4 in CD8α+ lymphocytes imply that they constitute a heterogeneous population different from found in non-mucosal tissues. PHA stimulation resulted in an up-regulation of CTL effector genes (perforin, granulysin and IFN-γ) in CD8α+ pronephrocytes, while both Th1 (IFN-γ) and Th2 (IL-4/13A) cytokines were up-regulated in CD8α⁻ pronephrocytes. Although the basic characteristics of CD8α+ lymphocytes seem similar in teleost and mammals, features such as the low proportion of teleost CD8α+ lymphocytes in blood and their high abundance in respiratory tissue reveal a unique dynamics and distribution. PMID:21352850

  7. CD8+ T cells in inflammatory demyelinating disease

    Weiss, Hanne A; Millward, Jason M; Owens, Trevor

    We review the contribution made by CD8+ T cells to inflammation in the central nervous system (CNS) in Multiple Sclerosis (MS), and discuss their role in the animal model Experimental Autoimmune Encephalomyelitis (EAE). We show that the inflammatory cytokines interferon-gamma and interleukin-17 are...... differentially regulated in CNS-infiltrating CD4+ and CD8+ T cells in EAE, and that CD8+ T cells regulate disease. In MS, CD8+ T cells appear to play a role in promotion of disease, so cytokine regulation is likely different in CD8+ T cells in MS and EAE...

  8. Case report: a unique pediatric case of a primary CD8 expressing ALK-1 positive anaplastic large cell lymphoma of skeletal muscle

    Gaiser Timo


    Full Text Available Abstract Primary involvement of skeletal muscle is a very rare event in ALK-1 positive anaplastic large cell lymphoma (ALCL. We describe a case of a 10-year old boy presenting with a three week history of pain and a palpable firm swelling at the dorsal aspect of the left thigh. Histological examination of the lesion revealed a tumoral and diffuse polymorphic infiltration of the muscle by large lymphoid cells. Tumor cells displayed eccentric, lobulated "horse shoe" or "kidney-shape" nuclei. The cells showed immunohistochemical positivity for CD30, ALK-1, CD2, CD3, CD7, CD8, and Perforin. Fluorescence in situ hybridization analysis revealed a characteristic rearrangement of the ALK-1 gene in 2p23 leading to the diagnosis of ALK-1 positive ALCL. Chemotherapy according to the ALCL-99-NHL-BFM protocol was initiated and resulted in a complete remission after two cycles. This case illustrates the unusual presentation of a pediatric ALCL in soft tissue with a good response to chemotherapy.

  9. Increased CD4 and CD8-positive T cell infiltrate signifies good prognosis in a subset of triple-negative breast cancer.

    Matsumoto, Hirofumi; Thike, Aye Aye; Li, Huihua; Yeong, Joe; Koo, Si-Lin; Dent, Rebecca Alexandra; Tan, Puay Hoon; Iqbal, Jabed


    Tumour-infiltrating lymphocytes (TILs) signify immune response to tumour in a variety of cancers including breast cancer. However, earlier studies examining the clinical significance of TILs in breast cancers have generated mixed results. There are only a few that address the relationship between TILs and clinical outcomes in triple-negative breast cancers (TNBC). The aim of this study is to evaluate the clinical significance of TILs that express CD4 + and CD8 + , in TNBC. Immunohistochemical staining of CD4 and CD8 was performed on tissue microarrays of 164 cases of TNBC. TILs were counted separately as intratumoral when within the cancer cell nests (iTILs) and as stromal when within cancer stroma (sTILs). High CD8 + iTILs and sTILs, and CD4 + iTILs correlated with histologic grade. On Kaplan-Meier analysis, a significantly better survival rate was observed in high CD8 + iTIL (disease-free survival, DFS: P = 0.004, overall survival, OS: P = 0.02) and both high CD4 + iTILs (DFS: P = 0.025, OS: P = 0.023) and sTILs (DFS: P = 0.01, OS: P = 0.002). In multivariate analysis, CD8 + iTILs (DFS: P = 0.0095), CD4 + sTILs (DFS: P = 0.0084; OS: P = 0.0118), and CD4 (high) CD8 (high) CD8 iTILs (DFS: P = 0.0121; OS: P = 0.0329) and sTILs (DFS: P = 0.0295) showed significantly better survival outcomes. These results suggest that high levels of both CD8 + iTILs and CD4 + sTILs as well as CD4 (high) CD8 (high) iTILs and sTILs are independent prognostic factors in TNBC. PMID:26960711

  10. Consensus nomenclature for CD8+ T cell phenotypes in cancer

    Apetoh, Lionel; Smyth, Mark J.; Drake, Charles G.; Abastado, Jean-Pierre; Apte, Ron N.; Ayyoub, Maha; Blay, Jean-Yves; Bonneville, Marc; Butterfield, Lisa H.; Caignard, Anne; Castelli, Chiara; Cavallo, Federica; Celis, Esteban; Chen, Lieping; Colombo, Mario P.; Comin-Anduix, Begoña; Coukos, Georges; Dhodapkar, Madhav V.; Dranoff, Glenn; Frazer, Ian H.; Fridman, Wolf-Hervé; Gabrilovich, Dmitry I.; Gilboa, Eli; Gnjatic, Sacha; Jäger, Dirk; Kalinski, Pawel; Kaufman, Howard L.; Kiessling, Rolf; Kirkwood, John; Knuth, Alexander; Liblau, Roland; Lotze, Michael T.; Lugli, Enrico; Marincola, Francesco; Melero, Ignacio; Melief, Cornelis J.; Mempel, Thorsten R.; Mittendorf, Elizabeth A.; Odun, Kunle; Overwijk, Willem W.; Palucka, Anna Karolina; Parmiani, Giorgio; Ribas, Antoni; Romero, Pedro; Schreiber, Robert D.; Schuler, Gerold; Srivastava, Pramod K.; Tartour, Eric; Valmori, Danila; van der Burg, Sjoerd H.; van der Bruggen, Pierre; van den Eynde, Benoît J.; Wang, Ena; Zou, Weiping; Whiteside, Theresa L.; Speiser, Daniel E.; Pardoll, Drew M.; Restifo, Nicholas P.; Anderson, Ana C.


    Whereas preclinical investigations and clinical studies have established that CD8+ T cells can profoundly affect cancer progression, the underlying mechanisms are still elusive. Challenging the prevalent view that the beneficial effect of CD8+ T cells in cancer is solely attributable to their cytotoxic activity, several reports have indicated that the ability of CD8+ T cells to promote tumor regression is dependent on their cytokine secretion profile and their ability to self-renew. Evidence has also shown that the tumor microenvironment can disarm CD8+ T cell immunity, leading to the emergence of dysfunctional CD8+ T cells. The existence of different types of CD8+ T cells in cancer calls for a more precise definition of the CD8+ T cell immune phenotypes in cancer and the abandonment of the generic terms “pro-tumor” and “antitumor.” Based on recent studies investigating the functions of CD8+ T cells in cancer, we here propose some guidelines to precisely define the functional states of CD8+ T cells in cancer. PMID:26137416

  11. Mast-Cell-Derived TNF Amplifies CD8+ Dendritic Cell Functionality and CD8+ T Cell Priming

    Jan Dudeck


    Full Text Available Mast cells are critical promoters of adaptive immunity in the contact hypersensitivity model, but the mechanism of allergen sensitization is poorly understood. Using Mcpt5-CreTNFFL/FL mice, we show here that the absence of TNF exclusively in mast cells impaired the expansion of CD8+ T cells upon sensitization and the T-cell-driven adaptive immune response to elicitation. T cells primed in the absence of mast cell TNF exhibited a diminished efficiency to transfer sensitization to naive recipients. Specifically, mast cell TNF promotes CD8+ dendritic cell (DC maturation and migration to draining lymph nodes. The peripherally released mast cell TNF further critically boosts the CD8+ T-cell-priming efficiency of CD8+ DCs, thereby linking mast cell effects on T cells to DC modulation. Collectively, our findings identify the distinct potential of mast cell TNF to amplify CD8+ DC functionality and CD8+ T-cell-dominated adaptive immunity, which may be of great importance for immunotherapy and vaccination approaches.

  12. CD8αα expression marks terminally differentiated human CD8+ T cells expanded in chronic viral infection

    Lucy Jane Walker


    Full Text Available The T cell co-receptor CD8αβ enhances T cell sensitivity to antigen, however studies indicate CD8αα has the converse effect and acts as a co-repressor. Using a combination of Thymic Leukaemia antigen (TL tetramer, which directly binds CD8αα, anti-CD161 and anti-Vα7.2 antibodies we have been able for the first time to clearly define CD8αα expression on human CD8 T cells subsets. In healthy controls CD8αα is most highly expressed by CD161 bright (CD161++ mucosal associated invariant T (MAIT cells, with CD8αα expression highly restricted to the TCR Vα7.2+ cells of this subset. We also identified CD8αα-expressing populations within the CD161 mid (CD161+ and negative (CD161- non-MAIT CD8 T cell subsets and show TL-tetramer binding to correlate with expression of CD8β at low levels in the context of maintained CD8α expression (CD8α+CD8βlow. In addition, we found CD161-CD8α+CD8βlow populations to be significantly expanded in the peripheral blood of HIV-1 and hepatitis B (mean of 47% and 40% of CD161- T cells respectively infected individuals. Such CD8αα expressing T cells are an effector-memory population (CD45RA-, CCR7-, CD62L- that express markers of activation and maturation (HLA-DR+, CD28-, CD27-, CD57+ and are functionally distinct, expressing greater levels of TNF-α and IFN-γ on stimulation and perforin at rest than their CD8α+CD8βhigh counterparts. Antigen-specific T cells in HLA-B*4201+HIV-1 infected patients are found within both the CD161-CD8α+CD8βhigh and CD161-CD8α+CD8βlow populations. Overall we have clearly defined CD8αα expressing human T cell subsets using the TL-tetramer, and have demonstrated CD161-CD8α+CD8βlow populations, highly expanded in disease settings, to co-express CD8αβ and CD8αα. Co-expression of CD8αα on CD8αβ T cells may impact on their overall function in-vivo and contribute to the distinctive phenotype of highly differentiated populations in HBV and HIV-1 infection.

  13. Induction of Specific CD8+ T Cells against Intracellular Bacteria by CD8+ T-Cell-Oriented Immunization Approaches

    Toshi Nagata


    Full Text Available For protection against intracellular bacteria such as Mycobacterium tuberculosis and Listeria monocytogenes, the cellular arm of adaptive immunity is necessary. A variety of immunization methods have been evaluated and are reported to induce specific CD8+ T cells against intracellular bacterial infection. Modified BCG vaccines have been examined to enhance CD8+ T-cell responses. Naked DNA vaccination is a promising strategy to induce CD8+ T cells. In addition to this strategy, live attenuated intracellular bacteria such as Shigella, Salmonella, and Listeria have been utilized as carriers of DNA vaccines in animal models. Vaccination with dendritic cells pulsed with antigenic peptides or the cells introduced antigen genes by virus vectors such as retroviruses is also a powerful strategy. Furthermore, vaccination with recombinant lentivirus has been attempted to induce specific CD8+ T cells. Combinations of these strategies (prime-boost immunization have been studied for the efficient induction of intracellular bacteria-specific CD8+ T cells.

  14. Changes in CD4+, CD8+, CD4+ CD8+, and Immunoglobulin M-Positive Peripheral Blood Mononuclear Cells of Postweaning Multisystemic Wasting Syndrome-Affected Pigs and Age-Matched Uninfected Wasted and Healthy Pigs Correlate with Lesions and Porcine Circovirus Type 2 Load in Lymphoid Tissues

    Darwich, Laila; Segalés, Joaquim; Domingo, Mariano; Mateu, Enric


    Forty-one 8- to 12-week-old wasted pigs were selected from several conventional farms with histories of postweaning multisystemic wasting syndrome (PMWS) and classified into two groups according to their porcine circovirus type 2 (PCV2) infection status, as determined by in situ hybridization (ISH). Twenty-four pigs tested positive for PCV2 (PCV2-positive group), while 17 pigs tested negative for PCV2 (PCV2-negative group). In addition, eight uninfected healthy pigs from an experimental farm were used as controls. Heparinized blood samples were taken to obtain peripheral blood mononuclear cells. The CD4+, CD8+, CD4+ CD8+ (double-positive [DP]), and immunoglobulin M-positive (IgM+) cell subsets were analyzed by flow cytometry with appropriate monoclonal antibodies. Histopathological studies were done to evaluate the apparent degrees of lymphocyte depletion in different lymphoid organs (superficial inguinal and mesenteric lymph nodes, Peyer's patches, tonsils, and spleen) and to determine the viral load of the PCV2 genome by using an ISH technique. Animals of the PCV2-positive group showed a significant downshift of the CD8+ and DP cell subsets compared to the other groups (P < 0.05). Moreover, in PCV2-positive pigs, the amount of PCV2 genome in lymphoid tissues was related to the degree of cell depletion in those tissues (P < 0.05) as well as to the relative decrease in IgM+ and CD8+ cells in peripheral blood. These data support the notion that PCV2-positive pigs might have an impaired immune response. PMID:11874858

  15. CD8+ T cells induce platelet clearance in the liver via platelet desialylation in immune thrombocytopenia

    Qiu, Jihua; Liu, Xuena; Li, Xiaoqing; Zhang, Xu; Han, Panpan; Zhou, Hai; Shao, Linlin; Hou, Yu; Min, Yanan; Kong, Zhangyuan; Wang, Yawen; Wei, Yu; Liu, Xinguang; Ni, Heyu; Peng, Jun; Hou, Ming


    In addition to antiplatelet autoantibodies, CD8+ cytotoxic T lymphocytes (CTLs) play an important role in the increased platelet destruction in immune thrombocytopenia (ITP). Recent studies have highlighted that platelet desialylation leads to platelet clearance via hepatocyte asialoglycoprotein receptors (ASGPRs). Whether CD8+ T cells induce platelet desialylation in ITP remains unclear. Here, we investigated the cytotoxicity of CD8+ T cells towards platelets and platelet desialylation in ITP. We found that the desialylation of fresh platelets was significantly higher in ITP patients with positive cytotoxicity of CD8+ T cells than those without cytotoxicity and controls. In vitro, CD8+ T cells from ITP patients with positive cytotoxicity induced significant platelet desialylation, neuraminidase-1 expression on the platelet surface, and platelet phagocytosis by hepatocytes. To study platelet survival and clearance in vivo, CD61 knockout mice were immunized and their CD8+ splenocytes were used. Platelets co-cultured with these CD8+ splenocytes demonstrated decreased survival in the circulation and increased phagocytosis in the liver. Both neuraminidase inhibitor and ASGPRs competitor significantly improved platelet survival and abrogated platelet clearance caused by CD8+ splenocytes. These findings suggest that CD8+ T cells induce platelet desialylation and platelet clearance in the liver in ITP, which may be a novel mechanism of ITP. PMID:27321376

  16. CD8(+) T cells induce platelet clearance in the liver via platelet desialylation in immune thrombocytopenia.

    Qiu, Jihua; Liu, Xuena; Li, Xiaoqing; Zhang, Xu; Han, Panpan; Zhou, Hai; Shao, Linlin; Hou, Yu; Min, Yanan; Kong, Zhangyuan; Wang, Yawen; Wei, Yu; Liu, Xinguang; Ni, Heyu; Peng, Jun; Hou, Ming


    In addition to antiplatelet autoantibodies, CD8(+) cytotoxic T lymphocytes (CTLs) play an important role in the increased platelet destruction in immune thrombocytopenia (ITP). Recent studies have highlighted that platelet desialylation leads to platelet clearance via hepatocyte asialoglycoprotein receptors (ASGPRs). Whether CD8(+) T cells induce platelet desialylation in ITP remains unclear. Here, we investigated the cytotoxicity of CD8(+) T cells towards platelets and platelet desialylation in ITP. We found that the desialylation of fresh platelets was significantly higher in ITP patients with positive cytotoxicity of CD8(+) T cells than those without cytotoxicity and controls. In vitro, CD8(+) T cells from ITP patients with positive cytotoxicity induced significant platelet desialylation, neuraminidase-1 expression on the platelet surface, and platelet phagocytosis by hepatocytes. To study platelet survival and clearance in vivo, CD61 knockout mice were immunized and their CD8(+) splenocytes were used. Platelets co-cultured with these CD8(+) splenocytes demonstrated decreased survival in the circulation and increased phagocytosis in the liver. Both neuraminidase inhibitor and ASGPRs competitor significantly improved platelet survival and abrogated platelet clearance caused by CD8(+) splenocytes. These findings suggest that CD8(+) T cells induce platelet desialylation and platelet clearance in the liver in ITP, which may be a novel mechanism of ITP. PMID:27321376

  17. Generation and Regulation of CD8+ Regulatory T Cells

    Linrong Lu; Harvey Cantor


    Research into the suppressive activity of CD4+FoxP3+ T regulatory cells (Treg) has defined a sublineage of CD4+ cells that contribute to self-tolerance and resistance to autoimmune disease. Much less attention has been given to the potential contribution of regulatory sublineages of CD8+ cells. Analysis of a small fraction of CD8+ cells that target autoreactive CD4+ cells through recognition of the MHC class Ib molecule Qa-1 in mouse and HLA-E in human has revitalized interest in CD8+ Treg. Here we summarize recent progress and future directions of research into the role of this CD8+ sublineage in resistance to autoimmune disease. Cellular & Molecular Immunology. 2008;5(6):401-406.

  18. Differential gene expression in CD8+ cells exhibiting noncytotoxic anti-HIV activity

    Suppressive subtractive hybridization with polymerase chain reaction was used to identify the gene(s) associated with the CD8+ cell noncytotoxic anti-HIV response. The differences in gene expression profiles of CD8+ cells from a pair of discordant HIV-positive identical twins were studied. Forty-nine genes were identified as expressed at higher levels in the CD8+ cells from the infected twin that inhibited viral replication. The differential expression of these genes was then evaluated using Q-PCR to determine if this gene expression pattern is evident in CD8+ cells from other HIV-positive subjects showing this antiviral activity. Three genes, including one unknown, were found to have significantly increased expression in antiviral CD8+ cells


    Hansen, Scott G.; Sacha, Jonah B.; Hughes, Colette M.; Ford, Julia C.; Burwitz, Benjamin J.; Scholz, Isabel; Gilbride, Roxanne M.; Lewis, Matthew S.; Gilliam, Awbrey N.; Ventura, Abigail B.; Malouli, Daniel; Xu, Guangwu; Richards, Rebecca; Whizin, Nathan; Reed, Jason S.


    CD8+ T cell responses focus on a small fraction of pathogen- or vaccine-encoded peptides, and for some pathogens, these restricted recognition hierarchies limit the effectiveness of anti-pathogen immunity. We found that simian immunodeficiency virus (SIV) protein-expressing Rhesus Cytomegalovirus (RhCMV) vectors elicit SIV-specific CD8+ T cells that recognize unusual, diverse and highly promiscuous epitopes, including dominant responses to epitopes restricted by class II major histocompatibil...

  20. Specific Control of Immunity by Regulatory CD8 T Cells

    XiaoleiTang; TrevorRFSmith


    T lymphocytes with dedicated suppressor function (Treg) play a crucial role in the homeostatic control of immunity in the periphery. Several Treg phenotypes have now been identified in the CD4 and CD8 T cell populations, suggesting their down-regulatory function in both human and animal models of autoimmunity, transplantation and tumor immunity. Here we will focus on the CD8 Treg population and their ability to specifically inhibit a pathogenic autoimmune response. This review will detail the current advances in the knowledge of CD8 Treg in the context of antigen specificity, phenotype, MHC restriction, mechanism of action, and priming. Cellular & Molecular Immunology. 2005;2(1):11-19.

  1. Adoptive immunotherapy via CD4+ versus CD8+ T cells

    Vy Phan-Lai


    Full Text Available The goal of cancer immunotherapy is to induce specific and durable antitumor immunity. Adoptive T cell therapy (ACT has garnered wide interest, particularly in regard to strategies to improve T cell efficacy in trials. There are many types of T cells (and subsets which can be selected for use in ACT. CD4+ T cells are critical for the regulation, activation and aid of host defense mechanisms and, importantly, for enhancing the function of tumor-specific CD8+ T cells. To date, much research in cancer immunotherapy has focused on CD8+ T cells, in melanoma and other cancers. Both CD4+ T cells and CD8+ T cells have been evaluated as ACT in mice and humans, and both are effective at eliciting antitumor responses. IL-17 producing CD4+ T cells are a new subset of CD4+ T cells to be evaluated in ACT models. This review discusses the benefits of adoptive immunotherapy mediated by CD8+ and CD4+ cells. It also discusses the various type of T cells, source of T cells, and ex vivo cytokine growth factors for augmenting clinical efficacy of ACT. [Biomed Res Ther 2016; 3(4.000: 588-595

  2. CD8α dendritic cells drive establishment of HSV-1 latency.

    Kevin R Mott

    Full Text Available It is generally accepted that CD8 T cells play the key role to maintain HSV-1 latency in trigeminal ganglia of ocularly infected mice. Yet, comparably little is known about the role of innate immunity in establishment of viral latency. In the current study, we investigated whether CD8α DCs impact HSV-1 latency by examining latency in the trigeminal ganglia (TG of wild-type (WT C57BL/6 versus CD8α-/- (lack functional CD8 T cells and CD8α+ DCs, CD8β-/- (have functional CD8α+ T cells and CD8α+ DCs, and β2m-/- (lack functional CD8 T cells but have CD8α+ DCs mice as well as BXH2 (have functional CD8 T cells but lack CD8α+ DCs versus WT C3H (have functional CD8α T cells and CD8α+ DCs mice. We also determined whether the phenotype of CD8α-/- and BXH2 mice could be restored to that of WT mice by adoptive transfer of WT CD8+ T cells or bone marrow (BM derived CD8α+ DCs. Our results clearly demonstrate that CD8α DCs, rather than CD8 T cells, are responsible for enhanced viral latency and recurrences.

  3. Programming CD8+ T cells for effective immunotherapy

    Hinrichs, Christian S.; Gattinoni, Luca; Restifo, Nicholas P


    The differentiation state of CD8+ T cells has emerged as a crucial determinant of their ability to respond to tumor and infection. Signals from T-cell receptors, co-stimulatory molecules and cytokine receptors direct the differentiation process. These signals ‘program’ sustained and heritable gene expression patterns that govern progressive differentiation and lineage commitment. The epigenetic mechanisms by which T cells are programmed are just beginning to be elucidated. Understanding the m...

  4. Migration of CD8+ T Cells into the Central Nervous System Gives Rise to Highly Potent Anti-HIV CD4dimCD8bright T Cells in a Wnt Signaling-Dependent Manner.

    Richards, Maureen H; Narasipura, Srinivas D; Seaton, Melanie S; Lutgen, Victoria; Al-Harthi, Lena


    The role of CD8(+) T cells in HIV control in the brain and the consequences of such control are unclear. Approximately 3% of peripheral CD8(+) T cells dimly express CD4 on their surface. This population is known as CD4(dim)CD8(bright) T cells. We evaluated the role of CD4(dim)CD8(bright) and CD8 single positive T cells in HIV-infected brain using NOD/SCID/IL-2rcγ(-/-) mice reconstituted with human PBMCs (NSG-huPBMC). All three T cell populations (CD4 single positive, CD8 single positive, and CD4(dim)CD8(bright)) were found in NSG-huPBMC mouse brain within 2 wk of infection. Wnts secreted from astrocytes induced CD4(dim)CD8(bright) T cells by 2-fold in vitro. Injection of highly purified CD8 single positive T cells into mouse brain induced CD4(dim)CD8(bright) T cells by 10-fold, which were proliferative and exhibited a terminally differentiated effector memory phenotype. Brain CD4(dim)CD8(bright) T cells from HIV-infected mice exhibited anti-HIV-specific responses, as demonstrated by induction of CD107ab post exposure to HIV peptide-loaded targets. Further, higher frequency of CD4(dim)CD8(bright) T cells (R = -0.62; p ≤ 0.001), but not CD8 single positive T cells (R = -0.24; p ≤ 0.27), negatively correlated with HIV gag mRNA transcripts in HIV-infected NSG-huPBMC brain. Together, these studies indicate that single positive CD8(+) T cells entering the CNS during HIV infection can give rise to CD4(dim)CD8(bright) T cells, likely through a Wnt signaling-dependent manner, and that these cells are associated with potent anti-HIV control in the CNS. Thus, CD4(dim)CD8(bright) T cells are capable of HIV control in the CNS and may offer protection against HIV-associated neurocognitive disorders. PMID:26582945

  5. Distribution, characterization, and induction of CD8+ regulatory T cells and IL-17-producing CD8+ T cells in nasopharyngeal carcinoma

    Li Jiang; Huang Zhou-Feng; Xiong Geng; Mo Hao-Yuan; Qiu Fang; Mai Hai-Qiang; Chen Qiu-Yan; He Jia; Chen Shu-peng; Zheng Li-Min; Qian Chao-Nan; Zeng Yi-Xin


    Abstract Background CD8+ effector cells often have an antitumor function in patients with cancer. However, CD8+Foxp3+ regulatory T cells (Tcregs) and interleukin (IL)-17-producing CD8+ T cells (Tc17 cells) also derive from the CD8+ T cell lineage. Their role in the antitumor response remains largely unknown. In the present study, we aimed to investigate the distribution, characterization, and generation of CD8+ Tcregs and Tc17 cells in NPC patients. Methods Peripheral blood and tumor biopsy t...

  6. Memory Stem T Cells in Autoimmune Disease: High Frequency of Circulating CD8+ Memory Stem Cells in Acquired Aplastic Anemia.

    Hosokawa, Kohei; Muranski, Pawel; Feng, Xingmin; Townsley, Danielle M; Liu, Baoying; Knickelbein, Jared; Keyvanfar, Keyvan; Dumitriu, Bogdan; Ito, Sawa; Kajigaya, Sachiko; Taylor, James G; Kaplan, Mariana J; Nussenblatt, Robert B; Barrett, A John; O'Shea, John; Young, Neal S


    Memory stem T cells (TSCMs) constitute a long-lived, self-renewing lymphocyte population essential for the maintenance of functional immunity. Hallmarks of autoimmune disease pathogenesis are abnormal CD4(+) and CD8(+) T cell activation. We investigated the TSCM subset in 55, 34, 43, and 5 patients with acquired aplastic anemia (AA), autoimmune uveitis, systemic lupus erythematosus, and sickle cell disease, respectively, as well as in 41 age-matched healthy controls. CD8(+) TSCM frequency was significantly increased in AA compared with healthy controls. An increased CD8(+) TSCM frequency at diagnosis was associated with responsiveness to immunosuppressive therapy, and an elevated CD8(+) TSCM population after immunosuppressive therapy correlated with treatment failure or relapse in AA patients. IFN-γ and IL-2 production was significantly increased in various CD8(+) and CD4(+) T cell subsets in AA patients, including CD8(+) and CD4(+) TSCMs. CD8(+) TSCM frequency was also increased in patients with autoimmune uveitis or sickle cell disease. A positive correlation between CD4(+) and CD8(+) TSCM frequencies was found in AA, autoimmune uveitis, and systemic lupus erythematosus. Evaluation of PD-1, CD160, and CD244 expression revealed that TSCMs were less exhausted compared with other types of memory T cells. Our results suggest that the CD8(+) TSCM subset is a novel biomarker and a potential therapeutic target for AA. PMID:26764034

  7. Involvement and prognosis value of CD8(+) T cells in giant cell arteritis.

    Samson, Maxime; Ly, Kim Heang; Tournier, Benjamin; Janikashvili, Nona; Trad, Malika; Ciudad, Marion; Gautheron, Alexandrine; Devilliers, Hervé; Quipourt, Valérie; Maurier, François; Meaux-Ruault, Nadine; Magy-Bertrand, Nadine; Manckoundia, Patrick; Ornetti, Paul; Maillefert, Jean-Francis; Besancenot, Jean-François; Ferrand, Christophe; Mesturoux, Laura; Labrousse, François; Fauchais, Anne-Laure; Saas, Philippe; Martin, Laurent; Audia, Sylvain; Bonnotte, Bernard


    CD8(+) T cells participate in the pathogenesis of some vasculitides. However, little is known about their role in Giant Cell Arteritis (GCA). This study was conducted to investigate CD8(+) T cell involvement in the pathogenesis of GCA. Analyses were performed at diagnosis and after 3 months of glucocorticoid treatment in 34 GCA patients and 26 age-matched healthy volunteers. Percentages of CD8(+) T-cell subsets, spectratype analysis of the TCR Vβ families of CD8(+) T cells, levels of cytokines and chemokines and immunohistochemistry of temporal artery biopsies (TAB) were assessed. Among total CD8(+) T cells, percentages of circulating cytotoxic CD8 T lymphocytes (CTL, CD3(+)CD8(+)perforin(+)granzymeB(+)), Tc17 (CD3(+)CD8(+)IL-17(+)), CD63(+)CD8(+) T cells and levels of soluble granzymes A and B were higher in patients than in controls, whereas the percentage of Tc1 cells (CD3(+)CD8(+)IFN-γ(+)) was similar. Moreover, CD8(+) T cells displayed a restricted TCR repertoire in GCA patients. Percentages of circulating CTL, Tc17 and soluble levels of granzymes A and B decreased after treatment. CXCR3 expression on CD8(+) T cells and its serum ligands (CXCL9, -10, -11) were higher in patients. Analyses of TAB revealed high expression of CXCL9 and -10 associated with infiltration by CXCR3(+)CD8(+) T cells expressing granzyme B and TiA1. The intensity of the CD8 T-cell infiltrate in TAB was predictive of the severity of the disease. This study demonstrates the implication and the prognostic value of CD8(+) T-cells in GCA and suggests that CD8(+) T-cells are recruited within the vascular wall through an interaction between CXCR3 and its ligands. PMID:27236507

  8. Praziquantel facilitates IFN-γ-producing CD8+ T cells (Tc1 and IL-17-producing CD8+ T cells (Tc17 responses to DNA vaccination in mice.

    Qiang Zou

    Full Text Available BACKGROUND: CD8(+ cytotoxic T lymphocytes (CTLs are crucial for eliminating hepatitis B virus (HBV infected cells. DNA vaccination, a novel therapeutic strategy for chronic virus infection, has been shown to induce CTL responses. However, accumulated data have shown that CTLs could not be effectively induced by HBV DNA vaccination. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report that praziquantel (PZQ, an anti-schistoma drug, could act as an adjuvant to overcome the lack of potent CTL responses by HBV DNA vaccination in mice. PZQ in combination with HBV DNA vaccination augmented the induction of CD8(+ T cell-dependent and HBV-specific delayed hypersensitivity responses (DTH in C57BL/6 mice. Furthermore, the induced CD8(+ T cells consisted of both Tc1 and Tc17 subtypes. By using IFN-γ knockout (KO mice and IL-17 KO mice, both cytokines were found to be involved in the DTH. The relevance of these findings to HBV immunization was established in HBsAg transgenic mice, in which PZQ also augmented the induction of HBV-specific Tc1 and Tc17 cells and resulted in reduction of HBsAg positive hepatocytes. Adoptive transfer experiments further showed that PZQ-primed CD8(+ T cells from wild type mice, but not the counterpart from IFN-γ KO or IL-17 KO mice, resulted in elimination of HBsAg positive hepatocytes. CONCLUSIONS/SIGNIFICANCE: Our results suggest that PZQ is an effective adjuvant to facilitate Tc1 and Tc17 responses to HBV DNA vaccination, inducing broad CD8(+ T cell-based immunotherapy that breaks tolerance to HBsAg.

  9. GATA-3 regulates the homeostasis and activation of CD8+ T cells1

    Tai, Tzong-Shyuan; Pai, Sung-Yun; Ho, I-Cheng


    GATA-3, a C2C2 type zinc finger transcription factor, regulates many steps of T cell development and differentiation. It is also required for optimal production of type 2 cytokines by CD8+ T cells. However, its role in the development and function of this subset of T cells is still poorly characterized. Here we report that GATA-3 is required for MHC-mediated positive selection and final maturation of CD8 single positive thymocytes. Deficiency of GATA-3 mediated by a CD4cre transgene led to ag...

  10. The positive prognostic effect of stromal CD8+ tumor-infiltrating T cells is restrained by the expression of HLA-E in non-small cell lung carcinoma

    Yazdi, Mehrdad Talebian; van Riet, Sander; van Schadewijk, Annemarie; Fiocco, Marta; van Hall, Thorbald; Taube, Christian; Hiemstra, Pieter S.; van der Burg, Sjoerd H.


    INTRODUCTION Tumor-infiltrating CD8+ T cells are associated with improved clinical outcomes in non-small cell lung cancer (NSCLC). Here we studied their prognostic effect in the context of the expression of HLA molecules that are key in tumor recognition (HLA-A, B and C) or suppression of immunity (HLA-E) as this is still unknown. METHODS Tumor tissue of 197 patients with resected pulmonary adenocarcinoma was analyzed for the presence of CD8+ T cells and the expression of β2-microglobulin, HL...

  11. Phenotypical and functional characterization of double-negative (CD4-CD8-) alpha beta T-cell receptor positive cells from an immunodeficient patient

    Illum, N; Ralfkiaer, E; Pallesen, G;


    . In contrast, the addition of a combination of Ca2+ ionophore and phorbol 12-myristate 13-acetate (PMA) restored the proliferative response of the DN T cells to almost normal levels. This observation strongly suggests that the protein kinase C activity of the DN T cells was intact, but that the normal...

  12. Mucosal SIV vaccines comprising inactivated virus particles and bacterial adjuvants induce CD8+T-regulatory cells that suppress SIV positive CD4+cell activation and prevent SIV infection in the macaque model.

    Jean Marie eAndrieu


    Full Text Available A new paradigm of mucosal vaccination against HIV infection has been investigated in the macaque model. A vaccine consisting of inactivated SIVmac239 particles together with a living bacterial adjuvant (either the Calmette & Guerin bacillus, lactobacillus plantarum or Lactobacillus rhamnosus was administered to macaques via the vaginal or oral/intragastic route. In contrast to all established human and veterinary vaccines, these three vaccine regimens did not elicit SIV-specific antibodies nor cytotoxic T-lymphocytes but induced a previously unrecognized population of non-cytolytic MHCIb/E-restricted CD8+T regulatory cells that suppressed the activation of SIV positive CD4+ T-lymphocytes. SIV reverse transcription was thereby blocked in inactivated CD4+ T-cells; the initial burst of virus replication was prevented and the vaccinated macaques were protected from a challenge infection. Three to 14 months after intragastric immunization, 24 macaques were challenged intrarectally with a high dose of SIVmac239 or with the heterologous strain SIV B670 (both strains grown on macaques PBMC. Twenty-three of these animals were found to be protected for up to 48 months while all 24 control macaques became infected. This protective effect against SIV challenge together with the concomitant identification of a robust ex-vivo correlate of protection suggests a new approach for developing an HIV vaccine in humans. The induction of this new class of CD8+ T regulatory cells could also possibly be used therapeutically for suppressing HIV replication in infected patients and this novel tolerogenic vaccine paradigm may have potential applications for treating a wide range of immune disorders and is likely to may have profound implications across immunology generally.

  13. Suppression of HIV Replication by CD8+ Regulatory T-Cells in Elite Controllers

    Lu, Wei; Chen, Song; Lai, Chunhui; Lai, Mingyue; Fang, Hua; Dao, Hong; Kang, Jun; Fan, Jianhua; Guo, Weizhong; Fu, Linchun; Andrieu, Jean-Marie


    We previously demonstrated in the Chinese macaque model that an oral vaccine made of inactivated SIV and Lactobacillus plantarum induced CD8+ regulatory T-cells, which suppressed the activation of SIV+CD4+ T-cells, prevented SIV replication, and protected macaques from SIV challenges. Here, we sought whether a similar population of CD8+ T-regs would induce the suppression of HIV replication in elite controllers (ECs), a small population (3‰) of HIV-infected patients with undetectable HIV replication. For that purpose, we investigated the in vitro antiviral activity of fresh CD8+ T-cells on HIV-infected CD4+ T-cells taken from 10 ECs. The 10 ECs had a classical genomic profile: all of them carried the KIR3DL1 gene and 9 carried at least 1 allele of HLA-B:Bw4-80Ile (i.e., with an isoleucine residue at position 80). In the nine HLA-B:Bw4-80Ile-positive patients, we demonstrated a strong viral suppression by KIR3DL1-expressing CD8+ T-cells that required cell-to-cell contact to switch off the activation signals in infected CD4+ T-cells. KIR3DL1-expressing CD8+ T-cells withdrawal and KIR3DL1 neutralization by a specific anti-killer cell immunoglobulin-like receptor (KIR) antibody inhibited the suppression of viral replication. Our findings provide the first evidence for an instrumental role of KIR-expressing CD8+ regulatory T-cells in the natural control of HIV-1 infection. PMID:27148256

  14. Functional classification of memory CD8(+) T cells by CX3CR1 expression.

    Böttcher, Jan P; Beyer, Marc; Meissner, Felix; Abdullah, Zeinab; Sander, Jil; Höchst, Bastian; Eickhoff, Sarah; Rieckmann, Jan C; Russo, Caroline; Bauer, Tanja; Flecken, Tobias; Giesen, Dominik; Engel, Daniel; Jung, Steffen; Busch, Dirk H; Protzer, Ulrike; Thimme, Robert; Mann, Matthias; Kurts, Christian; Schultze, Joachim L; Kastenmüller, Wolfgang; Knolle, Percy A


    Localization of memory CD8(+) T cells to lymphoid or peripheral tissues is believed to correlate with proliferative capacity or effector function. Here we demonstrate that the fractalkine-receptor/CX3CR1 distinguishes memory CD8(+) T cells with cytotoxic effector function from those with proliferative capacity, independent of tissue-homing properties. CX3CR1-based transcriptome and proteome-profiling defines a core signature of memory CD8(+) T cells with effector function. We find CD62L(hi)CX3CR1(+) memory T cells that reside within lymph nodes. This population shows distinct migration patterns and positioning in proximity to pathogen entry sites. Virus-specific CX3CR1(+) memory CD8(+) T cells are scarce during chronic infection in humans and mice but increase when infection is controlled spontaneously or by therapeutic intervention. This CX3CR1-based functional classification will help to resolve the principles of protective CD8(+) T-cell memory. PMID:26404698

  15. Peptide pool immunization and CD8+ T cell reactivity

    Rasmussen, Susanne B; Harndahl, Mikkel N; Buus, Anette Stryhn;


    peptide in the Elispot culture. Immunization with a mixture of the VSV-peptide and a "normal" peptide also resulted in IFNγ spot formation without addition of peptide to the assay culture. Peptide-tetramer staining of CD8(+) T cells from mice immunized with a mixture of VSV-peptide and "normal" peptide......Mice were immunized twice with a pool of five peptides selected among twenty 8-9-mer peptides for their ability to form stable complexes at 37°C with recombinant H-2K(b) (half-lives 10-15h). Vaccine-induced immunity of splenic CD8(+) T cells was studied in a 24h IFNγ Elispot assay. Surprisingly...... peptides induced normal peptide immunity i.e. the specific T cell reactivity in the Elispot culture was strictly dependent on exposure to the immunizing peptide ex vivo. However, immunization with two of the peptides, a VSV- and a Mycobacterium-derived peptide, resulted in IFNγ spot formation without...

  16. Expansion of CD8+ cells in autoimmune hemolytic anemia.

    Smirnova, S Ju; Sidorova, Ju V; Tsvetaeva, N V; Nikulina, O F; Biderman, B V; Nikulina, E E; Kulikov, S M; Sudarikov, A B


    Autoimmune hemolytic anemia (AIHA) is a rare blood disease associated with the production of auto-antibodies and autoimmune hemolysis. A critical role of B-cells in the development of AIHA has been demonstrated before. Here, we present the analysis of the clonal T-cell populations in patients with AIHA. Thirty-three patients with AIHA were included in this study. Thirteen patients with other anemias, 14 patients with other autoimmune conditions (SLE - 6, RA - 8) and 20 healthy donors were included in the study as a control group. The clonality of T-cell was evaluated by the assessment of the T-cell receptor gamma and beta chain gene rearrangements (TCRG and TCRB). The incidence of T-cell monoclonality detected in patients with AIHA was significantly higher compared to the control group. The persistence of T-cell clones did not correlate with the level of hemoglobin and other signs of remission or relapse and did not disappear after the therapy and clinical improvement (observation period was between 1 and 10 years). There was no correlation between the T-cell clonality and the gender, age, splenectomy, duration or severity of the disease. Fractionation of T-lymphocytes (CD4+, CD8+, CD4+25+) revealed that the monoclonal T-cells belonged to the CD8+ sub-population. We assume that besides a possible causative role of the T-cell clones in AIHA to autoimmune process, these clones do not directly participate in the development and maintenance of hemolysis. Most of the AIHA patients (48.5%) demonstrated a T-cell monoclonality, which requires monitoring and should be distinguished from T-cell tumors. PMID:26829107

  17. Effect of ageing on CMV-specific CD8 T cells from CMV seropositive healthy donors

    Alonso Corona


    Full Text Available Abstract Background Ageing is associated with changes in the immune system with substantial alterations in T-lymphocyte subsets. Cytomegalovirus (CMV is one of the factors that affect functionality of T cells and the differentiation and large expansions of CMV pp65-specific T cells have been associated with impaired responses to other immune challenges. Moreover, the presence of clonal expansions of CMV-specific T cells may shrink the available repertoire for other antigens and contribute to the increased incidence of infectious diseases in the elderly. In this study, we analyse the effect of ageing on the phenotype and frequency of CMV pp65-specific CD8 T cell subsets according to the expression of CCR7, CD45RA, CD27, CD28, CD244 and CD85j. Results Peripheral blood from HLA-A2 healthy young, middle-aged and elderly donors was analysed by multiparametric flow cytometry using the HLA-A*0201/CMV pp65495–504 (NLVPMVATV pentamer and mAbs specific for the molecules analysed. The frequency of CMV pp65-specific CD8 T cells was increased in the elderly compared with young and middle-aged donors. The proportion of naïve cells was reduced in the elderly, whereas an age-associated increase of the CCR7null effector-memory subset, in particular those with a CD45RAdim phenotype, was observed, both in the pentamer-positive and pentamer-negative CD8 T cells. The results also showed that most CMV pp65-specific CD8 T cells in elderly individuals were CD27/CD28 negative and expressed CD85j and CD244. Conclusion The finding that the phenotype of CMV pp65-specific CD8 T cells in elderly individuals is similar to the predominant phenotype of CD8 T cells as a whole, suggests that CMV persistent infections contributes to the age-related changes observed in the CD8 T cell compartment, and that chronic stimulation by other persistent antigens also play a role in T cell immunosenescence. Differences in subset distribution in elderly individuals showing a decrease in

  18. The Prognostic Significance of FoxP3+ T Cells and CD8+ T Cells in Colorectal Carcinomas.

    Argon, Asuman; Vardar, Enver; Kebat, Tulu; Erdinç, Ömer; Erkan, Nazif


    Recent studies report that tumor microenvironment effects prognosis of colorectal cancers. We analyzed the densities of FoxP3+ cells and CD8+ cells, the ratio of FoxP3+/CD8+ cells and the relationship between these parameters, clinicopathological features, and prognosis. A total of 186 colorectal adenocarcinoma were evaluated in terms of clinicopathological features. Immunohistochemically, densities of intratumoral (IT; IT-FoxP3) and nontumoral (NT; NT-FoxP3) FoxP3+ cells and IT-CD8 and NT-CD8 CD8+ cells were calculated. The ratio of Foxp3/CD8 was recorded. IT-FoxP3 and the ratio of IT-FoxP3/IT-CD8 were higher than NT-FoxP3 and the ratio of NT-FoxP3/NT-CD8, respectively. In multivariate analysis, high FoxP3+ cell density is the most important predictive marker after clinical stage and surgical margin positivity in disease-free survival and the most important predictive marker after clinical stage in overall survival (OS). Short OS time was correlated with clinical stage, decrease in IT-FoxP3, increasing age, number of metastatic lymph nodes, surgical margin positivity, satellite tumor nodule, medullary carcinoma, and the number of pericolorectal lymph nodes. The ratio of FoxP3/CD8 increased noticeably in the IT area, but no relationship was found with survival. The relationships of the cells with one another in the tumor microenvironment seem to have many secrets. Studies in large series supported by molecular techniques can illuminate those secrets to some extent. PMID:27481490

  19. CD8+ Cell Anti-HIV Activity Rapidly Increases Upon Discontinuation of Early Antiretroviral Therapy

    Killian, M. Scott; Roop, Jeremy; Ng, Sharon; Frederick M Hecht; Levy, Jay A.


    CD8+ lymphocytes can suppress HIV replication without killing the infected cells. This CD8+ cell noncytotoxic anti-HIV response (CNAR) is associated with a beneficial clinical course. In this longitudinal study of 16 participants in the Options Project at UCSF, we measured the ability of CD8+ lymphocytes to suppress HIV replication in CD4+ cells during primary HIV infection, early antiretroviral therapy, and after treatment. CD8+ lymphocytes from subjects with untreated primary HIV-1 in...

  20. Vitamin D receptor expression controls proliferation of naïve CD8+ T cells and development of CD8 mediated gastrointestinal inflammation

    Chen, Jing; Bruce, Danny; Cantorna, Margherita T.


    Background Vitamin D receptor (VDR) deficiency contributes to the development of experimental inflammatory bowel disease (IBD) in several different models. T cells have been shown to express the VDR, and T cells are targets of vitamin D. In this article we determined the effects of VDR expression on CD8+ T cells. Results VDR KO CD8+ T cells, but not WT CD8+ T cells, induced colitis in Rag KO recipients. In addition, co-transfer of VDR KO CD8+ T cells with naïve CD4+ T cells accelerated coliti...

  1. The Timing of Stimulation and IL-2 Signaling Regulate Secondary CD8 T Cell Responses.

    Shaniya H Khan


    Full Text Available Memory CD8 T cells provide protection to immune hosts by eliminating pathogen-infected cells during re-infection. While parameters influencing the generation of primary (1° CD8 T cells are well established, the factors controlling the development of secondary (2° CD8 T cell responses remain largely unknown. Here, we address the mechanisms involved in the generation and development of 2° memory (M CD8 T cells. We observed that the time at which 1° M CD8 T cells enter into immune response impacts their fate and differentiation into 2° M CD8 T cells. Late-entry of 1° M CD8 T cells into an immune response (relative to the onset of infection not only facilitated the expression of transcription factors associated with memory formation in 2° effector CD8 T cells, but also influenced the ability of 2° M CD8 T cells to localize within the lymph nodes, produce IL-2, and undergo Ag-driven proliferation. The timing of stimulation of 1° M CD8 T cells also impacted the duration of expression of the high-affinity IL-2 receptor (CD25 on 2° effector CD8 T cells and their sensitivity to IL-2 signaling. Importantly, by blocking or enhancing IL-2 signaling in developing 2° CD8 T cells, we provide direct evidence for the role of IL-2 in controlling the differentiation of Ag-driven 2° CD8 T cell responses. Thus, our data suggest that the process of 1° M to 2° M CD8 T cell differentiation is not fixed and can be manipulated, a notion with relevance for the design of future prime-boost vaccination approaches.

  2. CD8+ Treg cells suppress CD8+ T cell-responses by IL-10-dependent mechanism during H5N1 influenza virus infection

    Zou, Qiang; Wu, Bing; Xue, Jia; Fan, Xiaoxu; Feng, Congcong; Geng, Shuang; Wang, Ming; Wang, Bin


    Although Treg-cell-mediated suppression during infection or autoimmunity has been described, functions of Treg cells during highly pathogenic avian influenza virus infection remain poorly characterized. Here we found that in Foxp3-GFP transgenic mice, CD8+ Foxp3+ Treg cells, but not CD4+ Foxp3+ Treg cells, were remarkably induced during H5N1 infection. In addition to expressing CD25, the CD8+ Foxp3+ Treg cells showed a high level of GITR and produced IL-10. In an adoptive transfer model, CD8+...

  3. Temporal Dynamics of CD8+ T Cell Effector Responses during Primary HIV Infection

    Demers, Korey R.; Makedonas, George; Buggert, Marcus; Eller, Michael A.; Ratcliffe, Sarah J.; Goonetilleke, Nilu; Li, Chris K.; Eller, Leigh Anne; Rono, Kathleen; Maganga, Lucas; Nitayaphan, Sorachai; Kibuuka, Hannah; Routy, Jean-Pierre; Slifka, Mark K.; Haynes, Barton F.; Bernard, Nicole F.; Robb, Merlin L.; Betts, Michael R.


    The loss of HIV-specific CD8+ T cell cytolytic function is a primary factor underlying progressive HIV infection, but whether HIV-specific CD8+ T cells initially possess cytolytic effector capacity, and when and why this may be lost during infection, is unclear. Here, we assessed CD8+ T cell functional evolution from primary to chronic HIV infection. We observed a profound expansion of perforin+ CD8+ T cells immediately following HIV infection that quickly waned after acute viremia resolution. Selective expression of the effector-associated transcription factors T-bet and eomesodermin in cytokine-producing HIV-specific CD8+ T cells differentiated HIV-specific from bulk memory CD8+ T cell effector expansion. As infection progressed expression of perforin was maintained in HIV-specific CD8+ T cells with high levels of T-bet, but not necessarily in the population of T-betLo HIV-specific CD8+ T cells that expand as infection progresses. Together, these data demonstrate that while HIV-specific CD8+ T cells in acute HIV infection initially possess cytolytic potential, progressive transcriptional dysregulation leads to the reduced CD8+ T cell perforin expression characteristic of chronic HIV infection. PMID:27486665

  4. Tc17 CD8 T Cells: Functional Plasticity and Subset Diversity1

    Yen, Hung-Rong; Harris, Timothy J.; Wada, Satoshi; Grosso, Joseph F.; Getnet, Derese; Goldberg, Monica V.; Liang, Kai-Li; Bruno, Tullia C.; Pyle, Kristin J.; Chan, Siaw-Li; Anders, Robert A.; Trimble, Cornelia L.; Adler, Adam J.; Lin, Tzou-Yien; Pardoll, Drew M.


    IL-17-secreting CD8 T cells (Tc17) have been described in several settings, but little is known regarding their functional characteristics. While Tc1 cells produced IFN-γ and efficiently killed targets, Tc17 cells lacked lytic function in vitro. Interestingly, the small numbers of IFN-γ-positive or IL-17/IFN-γ-double-positive cells generated under Tc17 conditions also lacked lytic activity and expressed a similar pattern of cell surface proteins to IL-17-producing cells. As is the case for Th...

  5. Avian Influenza Viruses, Inflammation, and CD8+ T Cell Immunity

    Wang, Zhongfang; Loh, Liyen; Kedzierski, Lukasz; Kedzierska, Katherine


    Avian influenza viruses (AIVs) circulate naturally in wild aquatic birds, infect domestic poultry, and are capable of causing sporadic bird-to-human transmissions. AIVs capable of infecting humans include a highly pathogenic AIV H5N1, first detected in humans in 1997, and a low pathogenic AIV H7N9, reported in humans in 2013. Both H5N1 and H7N9 cause severe influenza disease in humans, manifested by acute respiratory distress syndrome, multi-organ failure, and high mortality rates of 60% and 35%, respectively. Ongoing circulation of H5N1 and H7N9 viruses in wild birds and poultry, and their ability to infect humans emphasizes their epidemic and pandemic potential and poses a public health threat. It is, thus, imperative to understand the host immune responses to the AIVs so we can control severe influenza disease caused by H5N1 or H7N9 and rationally design new immunotherapies and vaccines. This review summarizes our current knowledge on AIV epidemiology, disease symptoms, inflammatory processes underlying the AIV infection in humans, and recent studies on universal pre-existing CD8+ T cell immunity to AIVs. Immune responses driving the host recovery from AIV infection in patients hospitalized with severe influenza disease are also discussed. PMID:26973644

  6. Local induction of immunosuppressive CD8+ T cells in the gut-associated lymphoid tissues.

    Diana Fleissner

    Full Text Available BACKGROUND: In contrast to intestinal CD4(+ regulatory T cells (T(regs, the generation and function of immunomodulatory intestinal CD8(+ T cells is less well defined. To dissect the immunologic mechanisms of CD8(+ T cell function in the mucosa, reactivity against hemagglutinin (HA expressed in intestinal epithelial cells of mice bearing a MHC class-I-restricted T-cell-receptor specific for HA was studied. METHODOLOGY AND PRINCIPAL FINDINGS: HA-specific CD8(+ T cells were isolated from gut-associated tissues and phenotypically and functionally characterized for the expression of Foxp3(+ and their suppressive capacity. We demonstrate that intestinal HA expression led to peripheral induction of HA-specific CD8(+Foxp3(+ T cells. Antigen-experienced CD8(+ T cells in this transgenic mouse model suppressed the proliferation of CD8(+ and CD4(+ T cells in vitro. Gene expression analysis of suppressive HA-specific CD8(+ T cells revealed a specific up-regulation of CD103, Nrp1, Tnfrsf9 and Pdcd1, molecules also expressed on CD4(+ T(reg subsets. Finally, gut-associated dendritic cells were able to induce HA-specific CD8(+Foxp3(+ T cells. CONCLUSION AND SIGNIFICANCE: We demonstrate that gut specific antigen presentation is sufficient to induce CD8(+ T(regsin vivo which may maintain intestinal homeostasis by down-modulating effector functions of T cells.

  7. Nevirapine Inhibits the Anti-HIV Activity of CD8+ Cells

    Liu, Lianxing; Wang, Lin; Huang, Liusheng; Siu, Vincent; Teque, Fernando; Aweeka, Francesca T.; Levy, Jay A.


    Antiretroviral therapy (ART) significantly reduced the CD8+ cell non-cytotoxic anti-HIV response (CNAR) in twelve HIV-1-infected subjects (p < 0.0001). In separate experiments, CD8+ cells from long term survivors (LTS) were co-cultured with HIV-infected CD4+ cells using varying concentrations of anti-HIV drugs. The antiviral function of CD8+ cells from four of fourteen LTS was reduced with exposure to 10µM nevirapine (p < 0.05). The antiviral activity of CD8+ cells from two LTS was inhibited ...

  8. CD8+ T cells cause disability and axon loss in a mouse model of multiple sclerosis.

    Chandra Deb

    Full Text Available BACKGROUND: The objective of this study was to test the hypothesis that CD8+ T cells directly mediate motor disability and axon injury in the demyelinated central nervous system. We have previously observed that genetic deletion of the CD8+ T cell effector molecule perforin leads to preservation of motor function and preservation of spinal axons in chronically demyelinated mice. METHODOLOGY/PRINCIPAL FINDINGS: To determine if CD8+ T cells are necessary and sufficient to directly injure demyelinated axons, we adoptively transferred purified perforin-competent CD8+ spinal cord-infiltrating T cells into profoundly demyelinated but functionally preserved perforin-deficient host mice. Transfer of CD8+ spinal cord-infiltrating T cells rapidly and irreversibly impaired motor function, disrupted spinal cord motor conduction, and reduced the number of medium- and large-caliber spinal axons. Likewise, immunodepletion of CD8+ T cells from chronically demyelinated wildtype mice preserved motor function and limited axon loss without altering other disease parameters. CONCLUSIONS/SIGNIFICANCE: In multiple sclerosis patients, CD8+ T cells outnumber CD4+ T cells in active lesions and the number of CD8+ T cells correlates with the extent of ongoing axon injury and functional disability. Our findings suggest that CD8+ T cells may directly injure demyelinated axons and are therefore a viable therapeutic target to protect axons and motor function in patients with multiple sclerosis.

  9. Human lymph-node CD8+ T cells display an altered phenotype during systemic autoimmunity

    Ramwadhdoebe, Tamara H; Hähnlein, Janine; van Kuijk, Bo J; Choi, Ivy Y; van Boven, Leonard J; Gerlag, Danielle M; Tak, Paul P; van Baarsen, Lisa G


    Although many studies are focused on auto-reactive CD4+ T cells, the precise role of CD8+ T cells in autoimmunity is poorly understood. The objective of this study is to provide more insight into the phenotype and function CD8+ T cells during the development of autoimmune disease by studying CD8+ T cells in human lymph-node biopsies and peripheral blood obtained during the earliest phases of rheumatoid arthritis (RA). Here, we show that lymphoid pro-inflammatory CD8+ T cells exhibit a less-responsive phenotype already during the earliest phases of autoimmunity compared with healthy individuals. We found an increase in CD8+ memory T cells in lymphoid tissue during the earliest phases of autoimmunity, even before clinical onset of RA, accompanied by an increased frequency of non-circulating or recently activated (CD69+) CD8+ T cells in lymphoid tissue and peripheral blood. Importantly, lymphoid pro-inflammatory CD8+IL-17A+ T cells displayed a decreased capacity of cytokine production, which was related to disease activity in early RA patients. In addition, a decreased frequency of regulatory CD8+IL-10+ T cells in peripheral blood was also related to disease activity in early RA patients. Our results suggest that different CD8+ T-cell subsets are affected already during the earliest phases of systemic autoimmunity. PMID:27195110

  10. Polymicrobial sepsis alters Ag-dependent and -independent memory CD8 T cell functions1

    Duong, Sean; Condotta, Stephanie A.; Rai, Deepa; Martin, Matthew D.; Griffith, Thomas S.; Vladimir P. Badovinac


    Mortality from sepsis frequently results from secondary infections, and the extent to which sepsis affects pathogen-specific memory CD8 T cell responses remains unknown. Using the cecal-ligation and puncture (CLP) model of polymicrobial sepsis, we observed rapid apoptosis of pre-existing memory CD8 T cells after sepsis induction that led to a loss in CD8 T cell-mediated protection. Ag-sensitivity (functional avidity) and Ag-driven secondary expansion of memory CD8 T cells were decreased after...

  11. Sustained CD8+ T-cell responses induced after acute parvovirus B19 infection in humans

    Norbeck, Oscar; Isa, Adiba; Pöhlmann, Christoph;


    Murine models have suggested that CD8+ T-cell responses peak early in acute viral infections and are not sustained, but no evidence for humans has been available. To address this, we longitudinally analyzed the CD8+ T-cell response to human parvovirus B19 in acutely infected individuals. We...... observed striking CD8+ T-cell responses, which were sustained or even increased over many months after the resolution of acute disease, indicating that CD8+ T cells may play a prominent role in the control of parvovirus B19 and other acute viral infections of humans, including potentially those generated...

  12. The Secreted Protein Rv1860 of Mycobacterium tuberculosis Stimulates Human Polyfunctional CD8+ T Cells.

    Satchidanandam, Vijaya; Kumar, Naveen; Biswas, Sunetra; Jumani, Rajiv S; Jain, Chandni; Rani, Rajni; Aggarwal, Bharti; Singh, Jaya; Kotnur, Mohan Rao; Sridharan, Anand


    We previously reported that Rv1860 protein fromMycobacterium tuberculosisstimulated CD4(+)and CD8(+)T cells secreting gamma interferon (IFN-γ) in healthy purified protein derivative (PPD)-positive individuals and protected guinea pigs immunized with a DNA vaccine and a recombinant poxvirus expressing Rv1860 from a challenge with virulentM. tuberculosis We now show Rv1860-specific polyfunctional T (PFT) cell responses in the blood of healthy latentlyM. tuberculosis-infected individuals dominated by CD8(+)T cells, using a panel of 32 overlapping peptides spanning the length of Rv1860. Multiple subsets of CD8(+)PFT cells were significantly more numerous in healthy latently infected volunteers (HV) than in tuberculosis (TB) patients (PAT). The responses of peripheral blood mononuclear cells (PBMC) from PAT to the peptides of Rv1860 were dominated by tumor necrosis factor alpha (TNF-α) and interleukin-10 (IL-10) secretions, the former coming predominantly from non-T cell sources. Notably, the pattern of the T cell response to Rv1860 was distinctly different from those of the widely studiedM. tuberculosisantigens ESAT-6, CFP-10, Ag85A, and Ag85B, which elicited CD4(+)T cell-dominated responses as previously reported in other cohorts. We further identified a peptide spanning amino acids 21 to 39 of the Rv1860 protein with the potential to distinguish latent TB infection from disease due to its ability to stimulate differential cytokine signatures in HV and PAT. We suggest that a TB vaccine carrying these and other CD8(+)T-cell-stimulating antigens has the potential to prevent progression of latentM. tuberculosisinfection to TB disease. PMID:26843486

  13. Distribution, characterization, and induction of CD8+ regulatory T cells and IL-17-producing CD8+ T cells in nasopharyngeal carcinoma

    Li Jiang


    Full Text Available Abstract Background CD8+ effector cells often have an antitumor function in patients with cancer. However, CD8+Foxp3+ regulatory T cells (Tcregs and interleukin (IL-17-producing CD8+ T cells (Tc17 cells also derive from the CD8+ T cell lineage. Their role in the antitumor response remains largely unknown. In the present study, we aimed to investigate the distribution, characterization, and generation of CD8+ Tcregs and Tc17 cells in NPC patients. Methods Peripheral blood and tumor biopsy tissues from 21 newly diagnosed patients with nasopharyngeal carcinoma (NPC were collected, along with peripheral blood from 21 healthy donors. The biological characteristics of Tcregs and Tc17 cells from blood and tumor tissues were examined by intracellular staining, tetramer staining and fluorescence-activated cell sorting (FACS analysis. The suppressive function of Tcregs was investigated using a proliferation assay that involved co-culture of sorted CD8+CD25+ T cells with naïve CD4+ T cells in vitro. Results We observed an increased prevalence of Tcregs and Tc17 cells among tumor-infiltrating lymphocytes (TILs and different distribution among peripheral blood mononuclear cells (PBMCs in NPC patients. Cytokine profiles showed that the Tcregs expressed a high level of IL-10 and low level of transforming growth factor β, whereas Tc17 cells expressed a high level of tumor necrosis factor α. Interestingly, both subsets expressed a high level of interferon γ in TILs, and the Tcregs suppressed naïve CD4+ T cell proliferation by a cell contact-dependent mechanism in vitro. Moreover, we demonstrated the existence of Epstein-Barr virus latent membrane protein (LMP 1 and LMP2 antigen-specific Tcregs in NPC. Conclusions Our data provide new insights into the composition and function of CD8+ T-cell subsets in NPC, which may have an important influence on NPC immunotherapy.

  14. Memory CD8+ T cell differentiation in viral infection: A cell for all seasons

    Henry Radziewicz; Luke Uebelhoer; Bertram Bengsch; Arash Grakoui


    Chronic viral infections such as hepatitis B virus (HBV),hepatitis C virus (HCV) and human immunodeficiency virus (HIV) are major global health problems affecting more than 500 million people worldwide. Virus-specific CD8+ T cells play an important role in the course and outcome of these viral infections and it is hypothesized that altered or impaired differentiation of virusspecific CD8+ T cells contributes to the development of persistence and/or disease progression. A deeper understanding of the mechanisms responsible for functional differentiation of CD8+ T cells is essential for the generation of successful therapies aiming to strengthen the adaptive component of the immune system.

  15. Mesenchymal stem cells differentially modulate effector CD8+ T cell subsets and exacerbate experimental autoimmune encephalomyelitis.

    Glenn, Justin D; Smith, Matthew D; Calabresi, Peter A; Whartenby, Katharine A


    Mesenchymal stem cells (MSC) have emerged as a promising candidate for inflammatory suppression and disease amelioration, especially of neuro-inflammatory diseases such as multiple sclerosis (MS). Auto-reactive CD4+ and CD8+ T cells acquire pathogenic IFNγ-producing- (Type I) and IL-17A-producing- (Type 17) effector phenotypes in MS and its animal model experimental autoimmune encephalomyelitis (EAE). Although MSC have been extensively demonstrated to suppress pathogenic effector CD4+ T cells and CD4+ T cell-mediated EAE, surprisingly few studies have addressed their modulation of effector CD8+ T cells represented in MS or their impact on CD8+ T cell-mediated EAE. We find that MSC differentially modulate CD8+ T cell development depending on effector T cell subtype. MSC drive activated low-IFNγ producers toward an enhanced high-IFNγ Tc1-like phenotype but strongly inhibit the production of IL-17A and Tc17 polarization in vitro. These observations are underscored by differential MSC modulation of T cell activation, proliferation, and signature transcription factor up-regulation. In addition, effector CD8+ T cells co-cultured with MSC exhibited increased production of IL-2, a molecule known to enhance IFNγ, yet suppress IL-17A, production. Based on these in vitro effects on CD8+ T cells, we next evaluated their impact on the severity of EAE. To better evaluate CD8+ T cells, we immunized mice with MOG37-50 , which is a CD8-targeted epitope. Our results revealed a worsening of disease, consistent with their in vitro stimulation of Tc1 cells. These findings highlight the emerging duality of MSC in immune modulation and provide implications for their future use in immune-related diseases. PMID:24911892

  16. CD4+ T cell effects on CD8+ T cell location defined using bioluminescence.

    Mitra Azadniv

    Full Text Available T lymphocytes of the CD8+ class are critical in delivering cytotoxic function and in controlling viral and intracellular infections. These cells are "helped" by T lymphocytes of the CD4+ class, which facilitate their activation, clonal expansion, full differentiation and the persistence of memory. In this study we investigated the impact of CD4+ T cells on the location of CD8+ T cells, using antibody-mediated CD4+ T cell depletion and imaging the antigen-driven redistribution of bioluminescent CD8+ T cells in living mice. We documented that CD4+ T cells influence the biodistribution of CD8+ T cells, favoring their localization to abdominal lymph nodes. Flow cytometric analysis revealed that this was associated with an increase in the expression of specific integrins. The presence of CD4+ T cells at the time of initial CD8+ T cell activation also influences their biodistribution in the memory phase. Based on these results, we propose the model that one of the functions of CD4+ T cell "help" is to program the homing potential of CD8+ T cells.

  17. A Distinct Lung-Interstitium-Resident Memory CD8+ T Cell Subset Confers Enhanced Protection to Lower Respiratory Tract Infection

    Pavlo Gilchuk


    Full Text Available The nature and anatomic location of the protective memory CD8+ T cell subset induced by intranasal vaccination remain poorly understood. We developed a vaccination model to assess the anatomic location of protective memory CD8+ T cells and their role in lower airway infections. Memory CD8+ T cells elicited by local intranasal, but not systemic, vaccination with an engineered non-replicative CD8+ T cell-targeted antigen confer enhanced protection to a lethal respiratory viral challenge. This protection depends on a distinct CXCR3LO resident memory CD8+ T (Trm cell population that preferentially localizes to the pulmonary interstitium. Because they are positioned close to the mucosa, where infection occurs, interstitial Trm cells act before inflammation can recruit circulating memory CD8+ T cells into the lung tissue. This results in a local protective immune response as early as 1 day post-infection. Hence, vaccine strategies that induce lung interstitial Trm cells may confer better protection against respiratory pathogens.

  18. High Frequency of CD8 Positive Lymphocyte Infiltration Correlates with Lack of Lymph Node Involvement in Early Rectal Cancer

    Silvio Däster


    Full Text Available Aims. A trend towards local excision of early rectal cancers has prompted us to investigate if immunoprofiling might help in predicting lymph node involvement in this subgroup. Methods. A tissue microarray of 126 biopsies of early rectal cancer (T1 and T2 was stained for several immunomarkers of the innate and the adaptive immune response. Patients’ survival and nodal status were analyzed and correlated with infiltration of the different immune cells. Results. Of all tested markers, only CD8 (P=0.005 and TIA-1 (P=0.05 were significantly more frequently detectable in early rectal cancer biopsies of node negative as compared to node positive patients. Although these two immunomarkers did not display prognostic effect “per se,” CD8+ and, marginally, TIA-1 T cell infiltration could predict nodal involvement in univariate logistic regression analysis (OR 0.994; 95% CI 0.992–0.996; P=0.009 and OR 0.988; 95% CI 0.984–0.994; P=0.05, resp.. An algorithm significantly predicting the nodal status in early rectal cancer based on CD8 together with vascular invasion and tumor border configuration could be calculated (P<0.00001. Conclusion. Our data indicate that in early rectal cancers absence of CD8+ T-cell infiltration helps in predicting patients’ nodal involvement.

  19. Induction of cytotoxic CD8+CD56+ T cells from human thymocytes by interleukin-15

    Thulesen, S; Nissen, Mogens Holst; Ødum, N; Röpke, C


    CD8(+) CD56(+) cells isolated from human peripheral blood lymphocytes have been shown recently to represent a population of cytotoxic active T cells. However, it is not known if these cells are intrathymically or extrathymically developed or how these cells are influenced by growth factors. In the...... present study, we investigated the effects of interleukin-2 (IL-2) and IL-15 on human thymocytes with respect to development of CD8(+) CD56(+) T cells. Freshly isolated thymocytes contain few CD8(+) CD56(+) cells, but the number of these cells increases significantly when thymocytes are grown in the...... presence of IL-15 or IL-2. However, IL-15 induced a significantly higher fraction of CD8(+) CD56(+) cells compared with IL-2. Thus, although IL-2 and IL-15 are known to have a number of redundant functions, we here demonstrate that IL-15 is superior to IL-2 in inducing CD8(+) CD56(+) T cells from cultures...

  20. Study on the expression of HLA-DR/CD69 on CD4 +/CD8 + T cells in the treatment of HBeAg-positive chronic hepatitis B with interferon alfa-2b%干扰素α-2b治疗HBeAg阳性慢性乙型肝炎患者CD4+/CD8+T细胞活化分子CD69和HLA-DR的表达

    石庆凤; 宋吉奎; 张颖新; 袁建国; 王思奎; 李庆方; 赵红奎


    目的 观察HBeAg阳性慢性乙型肝炎患者干扰素α-2b治疗前、中、后期CD4+/CD8+T细胞的活性与疗效的相关性.方法 32例患者隔日1次干扰素5 MU肌注,共24周.抽取干扰素α-2b治疗前,治疗1、4、12、24周的外周静脉血,密度梯度离心法分离获得外周血单个核细胞(PBMC),流式细胞仪检测CD4+/CD8+T细胞比例及CD4+/CD8+T细胞表面CD69、HLA-DR的表达.结果 干扰素α-2b治疗结束,HBV DNA含量转阴者12例(37%),其中HBeAg、抗-HBe血清转换5例(16%);12例治疗无效(37%)及8例HBV DNA抑制(25%).HBV DNA转阴者治疗前,治疗1、4周时CD69、HLA-DR表达率较治疗无效及HBV DNA抑制者高,差异有统计学意义(P<0.05).HBV DNA转阴者治疗后1周时,CD69、HLA-DR表达率最高;4周时CD4+/CD8+T细胞的CD69、HLA-DR表达率较前下降,但仍保持较高表达率;12周时CD69、HLA-DR表达率较前更下降,与治疗无效及HBV DNA抑制者相比差异无统计学意义(P>0.05);24周时CD69、HLA-DR表达率最低,与治疗无效及HBV DNA抑制者比较差异有统计学意义(P<0.05).结论 HBeAg阳性慢性乙型肝炎患者CD4+/CD8+T细胞活化分子CD69、HLA-DR的表达,对干扰素α-2b的疗效有预测作用.%Objective To study the efficacy prediction and the activation of CD4 + /CD8 + T cells in the treatment of HBeAg - positive chronic hepatitis B with interferon alfa -2b. Methods 32 patients were given interferon alfa -2b 5 MU every other day for 24 weeks. PBH|C were isolated from fresh peripheral blood of chronic severe hepatitis B patients by Ficoll - Hypaque density gradient centrifugation and cultured with plastic - adherence method. FACS was used to analyze the expression of the CD4 + /CD8 + T cells surface markers, including human leukocyte antigen - DR ( HLA - DR) and CD69. Results At the end of treatment, HBV - DNA levels loss rates were 37% (12 cases) , including HBeAg seroconversion in 5 cases(16% ). In 8 cases(25% ) HBV - DNA

  1. Why Do CD8+ T Cells become Indifferent to Tumors: A Dynamic Modeling Approach.

    Campbell, Colin; Zhang, Ranran; Haley, Jeremy S; Liu, Xin; Loughran, Thomas; Schell, Todd D; Albert, Réka; Thakar, Juilee


    CD8+ T cells have the potential to influence the outcome of cancer pathogenesis, including complete tumor eradication or selection of malignant tumor escape variants. The Simian virus 40 large T-antigen (Tag) oncoprotein promotes tumor formation in Tag-transgenic mice and also provides multiple target determinants (sites) for responding CD8+ T cells in C57BL/6 (H-2(b)) mice. To understand the in vivo quantitative dynamics of CD8+ T cells after encountering Tag, we constructed a dynamic model from in vivo-generated data to simulate the interactions between Tag-expressing cells and CD8+ T cells in distinct scenarios including immunization of wild-type C57BL/6 mice and of Tag-transgenic mice that develop various tumors. In these scenarios the model successfully reproduces the dynamics of both the Tag-expressing cells and antigen-specific CD8+ T cell responses. The model predicts that the tolerance of the site-specific T cells is dependent on their apoptosis rates and that the net growth of CD8+ T cells is altered in transgenic mice. We experimentally validate both predictions. Our results indicate that site-specific CD8+ T cells have tissue-specific apoptosis rates affecting their tolerance to the tumor antigen. Moreover, the model highlights differences in apoptosis rates that contribute to compromised CD8+ T cell responses and tumor progression, knowledge of which is essential for development of cancer immunotherapy. PMID:21808621

  2. Heterogeneity in the differentiation and function of CD8⁺ T cells.

    Mittrücker, Hans-Willi; Visekruna, Alexander; Huber, Magdalena


    It is well established that CD8(+) T cells constitute an important branch of adaptive immunity contributing to clearance of intracellular pathogens and providing long-term protection. These functions are mostly fulfilled by the best characterized subpopulation of CD8(+) T cells, the cytotoxic T lymphocytes (also called Tc1 cells), owing to their ability to kill infected cells and to secrete cytokines such as interferon-γ and tumor necrosis factor-α. However, there is growing evidence for alternative CD8(+) T cell fates influencing CD4(+) T-cell-mediated responses in the context of allergy, autoimmunity and infections. Thus, like subpopulations of CD4(+) T cells, also CD8(+) T cells under particular conditions acquire the expression of interleukin (IL)-4, IL-5, IL-9, IL-13, IL-17 or suppressive activity and thereby influence immune responses. The process of CD8(+) T-cell differentiation is dictated by antigen strength, co-stimulatory molecules and cytokines. These environmental cues induce transcription factors further specifying CD8(+) T-cell decision into Tc1, Tc2, Tc9, Tc17 or CD8(+) T regulatory fate. Here, we discuss our current understanding about functional diversity of effector CD8(+) T cells and contribution of transcription factors to this process. PMID:24879097

  3. Qualitative and quantitative analysis of adenovirus type 5 vector-induced memory CD8 T cells

    Steffensen, Maria Abildgaard; Holst, Peter Johannes; Steengaard, Sanne Skovvang; Jensen, Benjamin Anderschou Holbech; Bartholdy, Christina; Buus, Anette Stryhn; Christensen, Jan Pravsgaard; Thomsen, Allan Randrup


    It has been reported that adenovirus (Ad) primed CD8 T cells may display a distinct and partially exhausted phenotype. Given the practical implications of this claim, we decided to analyze in detail the quality of Ad-primed CD8 T cells directly comparing these cells to CD8 T cells induced through...... infection with lymphocytic choriomeningitis virus. We found that localized immunization with intermediate doses of Ad vector induce a moderate number of functional CD8 T cells, which qualitatively match those found in LCMV-infected mice. Numbers of these cells may be efficiently increased by additional...... leads to the generation of a population of memory cells characterized by relatively low CD27 expression and high CD127 and KLRG1 expression. These memory CD8 T cells are capable of proliferating in response to viral challenge, and protect against infection with live virus. Furthermore, viral challenge...

  4. HDAC1 controls CD8+ T cell homeostasis and antiviral response.

    Roland Tschismarov

    Full Text Available Reversible lysine acetylation plays an important role in the regulation of T cell responses. HDAC1 has been shown to control peripheral T helper cells, however the role of HDAC1 in CD8+ T cell function remains elusive. By using conditional gene targeting approaches, we show that LckCre-mediated deletion of HDAC1 led to reduced numbers of thymocytes as well as peripheral T cells, and to an increased fraction of CD8+CD4- cells within the CD3/TCRβlo population, indicating that HDAC1 is essential for the efficient progression of immature CD8+CD4- cells to the DP stage. Moreover, CD44hi effector CD8+ T cells were enhanced in mice with a T cell-specific deletion of HDAC1 under homeostatic conditions and HDAC1-deficient CD44hi CD8+ T cells produced more IFNγ upon ex vivo PMA/ionomycin stimulation in comparison to wild-type cells. Naïve (CD44l°CD62L+ HDAC1-null CD8+ T cells displayed a normal proliferative response, produced similar amounts of IL-2 and TNFα, slightly enhanced amounts of IFNγ, and their in vivo cytotoxicity was normal in the absence of HDAC1. However, T cell-specific loss of HDAC1 led to a reduced anti-viral CD8+ T cell response upon LCMV infection and impaired expansion of virus-specific CD8+ T cells. Taken together, our data indicate that HDAC1 is required for the efficient generation of thymocytes and peripheral T cells, for proper CD8+ T cell homeostasis and for an efficient in vivo expansion and activation of CD8+ T cells in response to LCMV infection.

  5. MEK kinase 1 is a negative regulator of virus-specific CD8(+) T cells

    Labuda, Tord; Christensen, Jan Pravsgaard; Rasmussen, Susanne; Bonnesen, Barbara; Karin, Michael; Thomsen, Allan Randrup; Ødum, Niels


    in the generation of a virus-specific immune response. Mekk1(DeltaKD) mice challenged with vesicular stomatitis virus (VSV) showed a fourfold increase in splenic CD8(+) T cell numbers. In contrast, the number of splenic T cells in infected WT mice was only marginally increased. The CD8(+) T cell...... result of increased proliferation, since a significantly higher percentage of virus-specific Mekk1(DeltaKD) CD8(+) T cells incorporated BrdU as compared to virus-specific WT CD8(+) T cells. In contrast, similar levels of apoptosis were detected in Mekk1(DeltaKD) and WT T cells following VSV infection....... These results strongly suggest that MEKK1 plays a negative regulatory role in the expansion of virus-specific CD8(+) T cells in vivo....

  6. CD8+ T Cells Complement Antibodies in Protecting against Yellow Fever Virus

    Bassi, Maria R; Kongsgaard, Michael; Steffensen, Maria A; Fenger, Christina; Rasmussen, Michael; Skjødt, Karsten; Finsen, Bente; Buus, Anette Stryhn; Buus, Søren; Christensen, Jan P; Thomsen, Allan Randrup


    of YF-17D infection. Using different strains of knockout mice, we found that CD4(+) T cells, B cells, and Abs are required for full clinical protection of vaccinated mice, whereas CD8(+) T cells are dispensable for long-term survival after intracerebral challenge. However, by analyzing the immune...... can still induce some antiviral protection, and in vivo depletion of CD8(+) T cells from these animals revealed a pivotal role for CD8(+) T cells in controlling virus replication in the absence of a humoral response. Finally, we demonstrated that effector CD8(+) T cells also contribute to viral...... control in the presence of circulating YF-specific Abs. To our knowledge, this is the first time that YF-specific CD8(+) T cells have been demonstrated to possess antiviral activity in vivo....

  7. CXCR3 expression defines a novel subset of innate CD8+ T cells that enhance immunity against bacterial infection and cancer upon stimulation with IL-15

    Oghumu, Steve; Terrazas, Cesar A.; Varikuti, Sanjay; Kimble, Jennifer; Vadia, Stephen; Yu, Lianbo; Seveau, Stephanie; Abhay R Satoskar


    Innate CD8+ T cells are a heterogeneous population with developmental pathways distinct from conventional CD8+ T cells. However, their biology, classification, and functions remain incompletely understood. We recently demonstrated the existence of a novel population of chemokine (C-X-C motif) receptor 3 (CXCR3)-positive innate CD8+ T cells. Here, we investigated the functional properties of this subset and identified effector molecules and pathways which mediate their function. Adoptive trans...

  8. Human MAIT and CD8αα cells develop from a pool of type-17 precommitted CD8+ T cells

    Walker, Lucy J.; Kang, Yu-Hoi; Smith, Matthew O.; Tharmalingham, Hannah; Ramamurthy, Narayan; Fleming, Vicki M.; Sahgal, Natasha; Leslie, Alistair; Oo, Ye; Geremia, Alessandra; Scriba, Thomas J.; Hanekom, Willem A; Lauer, Georg M.; Lantz, Olivier; Adams, David H


    Human mucosal associated invariant T (MAIT) CD8+ and Tc17 cells are important tissue-homing cell populations, characterized by high expression of CD161 (++) and type-17 differentiation, but their origins and relationships remain poorly defined. By transcriptional and functional analyses, we demonstrate that a pool of polyclonal, precommitted type-17 CD161++CD8αβ+ T cells exist in cord blood, from which a prominent MAIT cell (TCR Vα7.2+) population emerges post-natally. During this expansion, ...

  9. Tissue signatures influence the activation of intrahepatic CD8+ T cells against malaria sporozoites

    Alexandre eMorrot


    Full Text Available Plasmodium sporozoites and liver stages express antigens that are targeted to the MHC-Class I antigen-processing pathway. After the introduction of Plasmodium sporozoites by Anopheles mosquitoes, bone marrow-derived dendritic cells in skin-draining lymph nodes are the first cells to cross-present parasite antigens and elicit specific CD8+ T cells. One of these antigens is the immunodominant circumsporozoite protein (CSP. The CD8+ T cell-mediated protective immune response against CSP is dependent on the interleukin loop involving IL-4 receptor expression on CD8+ cells and IL-4 secretion by CD4+ T cell helpers. In a few days, these CD8+ T cells re-circulate to secondary lymphoid organs and the liver. In the liver, the hepatic sinusoids are enriched with cells, such as dendritic, sinusoidal endothelial and Kupffer cells, that are able to cross-present MHC class I antigens to intrahepatic CD8+ T cells. Specific CD8+ T cells actively find infected hepatocytes and target intra-cellular parasites through mechanisms that are both Interferon-g-dependent and -independent. Immunity is mediated by CD8+ T effector or effector-memory cells and, when present in high numbers, these cells can provide sterilizing immunity. Human vaccination trials with recombinant formulations or attenuated sporozoites have yet to achieve the high numbers of specific effector T cells that are required for sterilizing immunity. In spite of the limited number of specific CD8+ T cells, attenuated sporozoites provided multiple times by the endovenous route provided a high degree of protective immunity. These observations highlight that CD8+ T cells may be useful for improving antibody-mediated protective immunity to pre-erythrocytic stages of malaria parasites.

  10. CD3+CD8+CD161high Tc17 cells are depleted in HIV-infection.

    Gaardbo, Julie Christine; Hartling, Hans Jakob; Thorsteinsson, Kristina; Ullum, Henrik; Nielsen, Susanne Dam


    CD8 Tc17 cells with pro-inflammatory properties have only recently been acknowledged, and Tc17 cells in HIV-infection are not described. CD3CD8CD161 Tc17 cells and the production of interleukin (IL)-17 were examined in untreated and treated HIV-infected patients, HIV-hepatitis C virus co-infected patients, and healthy controls. Depletion of CD3CD8CD161 Tc17 cells and diminished production of IL-17 in HIV-infected patients were found. The level of Tc17 cells was associated with the CD4 cell count in treated patients. PMID:23135168

  11. Identification of heme oxygenase-1-specific regulatory CD8+ T cells in cancer patients

    Andersen, Mads Hald; Sørensen, Rikke Baek; Brimnes, Marie K;


    the antigens they recognize. Here, we describe what we believe to be the first natural target for CD8+ Tregs. Naturally occurring HLA-A2-restricted CD8+ T cells specific for the antiinflammatory molecule heme oxygenase-1 (HO-1) were able to suppress cellular immune responses with outstanding efficacy...

  12. Inhibiting glycolytic metabolism enhances CD8+ T cell memory and antitumor function

    Sukumar, Madhusudhanan; Liu, Jie; Ji, Yun; Subramanian, Murugan; Crompton, Joseph G.; Yu, Zhiya; Roychoudhuri, Rahul; Palmer, Douglas C.; Muranski, Pawel; Karoly, Edward D; Mohney, Robert P.; Klebanoff, Christopher A.; Lal, Ashish; Finkel, Toren; Restifo, Nicholas P.


    Naive CD8+ T cells rely upon oxidation of fatty acids as a primary source of energy. After antigen encounter, T cells shift to a glycolytic metabolism to sustain effector function. It is unclear, however, whether changes in glucose metabolism ultimately influence the ability of activated T cells to become long-lived memory cells. We used a fluorescent glucose analog, 2-NBDG, to quantify glucose uptake in activated CD8+ T cells. We found that cells exhibiting limited glucose incorporation had ...

  13. CD8alpha/alpha+ T-cells and Immune Memory

    Magalhaes, Isabelle


    A better understanding of T-cell memory formation is crucial for rationale vaccine design and the identification of correlates of immune protection. The CD8alphaalpha homodimer expressed on CD8+ T-cells is not anymore considered to represent a TCR co-receptor, it may rather represent a mechanism to modulate T-cell avidity and identify a subset of memory T-cells. The aim of the work presented in this thesis was to characterize the CD8alphaalpha+ T-cell compartment in the cont...

  14. CD3+CD8+CD161high Tc17 cells are depleted in HIV-infection

    Gaardbo, Julie Christine; Hartling, Hans Jakob; Thorsteinsson, Kristina;


    CD8+ Tc17 cells with pro-inflammatory properties have only recently been acknowledged, and Tc17 cells in HIV-infection are undescribed. CD3+CD8+CD161 Tc17 cells and the production of Interleukin-17 were examined in untreated and treated HIV-infected patients, HIV-HCV co-infected patients and...... healthy controls. Depletion of CD3+CD8+CD161 Tc17 cells and diminished production of Interleukin-17 in HIV-infected patients was found. The level of Tc17 cells was associated with the level of the CD4+ count in treated patients....

  15. IL-17A secretion by CD8+ T cells supports Th17-mediated autoimmune encephalomyelitis

    Huber, Magdalena; Heink, Sylvia; Pagenstecher, Axel; Reinhard, Katharina; Ritter, Josephine; Visekruna, Alexander; Guralnik, Anna; Bollig, Nadine; Jeltsch, Katharina; Heinemann, Christina; Wittmann, Eva; Buch, Thorsten; da Costa, Olivia Prazeres; Brüstle, Anne; Brenner, Dirk


    IL-17–producing CD8+ T (Tc17) cells are detectible in multiple sclerosis (MS) lesions; however, their contribution to the disease is unknown. To identify functions of Tc17 cells, we induced EAE, a murine model of MS, in mice lacking IFN regulatory factor 4 (IRF4). IRF4-deficient mice failed to generate Tc17 and Th17 cells and were resistant to EAE. After adoptive transfer of WT CD8+ T cells and subsequent immunization for EAE induction in these mice, the CD8+ T cells developed a Tc17 phenotyp...

  16. HTLV-1 specific CD8+ T cell function augmented by blockade of 2B4/CD48 interaction in HTLV-1 infection.

    Chibueze Chioma Ezinne

    Full Text Available CD8+ T cell response is important in the response to viral infections; this response though is regulated by inhibitory receptors. Expression of inhibitory receptors has been positively correlated with CD8+ T cell exhaustion; the consequent effect of simultaneous blockade of these inhibitory receptors on CD8+ T cell response in viral infections have been studied, however, the role of individual blockade of receptor-ligand pair is unclear. 2B4/CD48 interaction is involved in CD8+T cell regulation, its signal transducer SAP (signaling lymphocyte activation molecule (SLAM-associated protein is required for stimulatory function of 2B4/CD244 on lymphocytes hence, we analyzed 2B4/CD244 (natural killer cell receptor and SAP (signaling lymphocyte activation molecule(SLAM-associated protein on total CD8+ and HTLV-1 specific CD8+T cells in HTLV-1 infection and the effect of blockade of interaction with ligand CD48 on HTLV-1 specific CD8+ T cell function. We observed a high expression of 2B4/CD244 on CD8+ T cells relative to uninfected and further upregulation on HTLV-1 specific CD8+ T cells. 2B4+ CD8+ T cells exhibited more of an effector and terminally differentiated memory phenotype. Blockade of 2B4/CD48 interaction resulted in improvement in function via perforin expression and degranulation as measured by CD107a surface mobilization on HTLV-1 specific CD8+ T cells. In the light of these findings, we thus propose an inhibitory role for 2B4/CD48 interaction on CD8+T cell function.

  17. Alpha 4 integrin directs virus-activated CD8+ T cells to sites of infection

    Christensen, Jan Pravsgaard; Andersson, E C; Scheynius, A; Marker, O; Thomsen, Allan Randrup


    response is induced, which is associated with marked CD8+ cell-mediated inflammation. Two expressions of LCMV-induced inflammation were studied: meningitis induced by intracerebral infection and adoptive transfer of virus-specific delayed-type hypersensitivity. Our previous studies have shown that LCMV...... infection results in the appearance of activated CD8+ cells with an increased expression of VLA-4. In this study we have compared various T cell high and low responder situations, and these experiments revealed that acute inflammation correlates directly with VLA-4 expression on splenic CD8+ cells. This...... ability to transfer virus-specific, delayed-type hypersensitivity when the donor cells were given i.v., but not when the cells were injected directly into the test site. Co-transfer of CD8-depleted cells with anti-VLA-4-blocked cells did not reveal any cooperation. Taken together, these results indicate...

  18. Acetyl CoA Carboxylase 2 Is Dispensable for CD8+ T Cell Responses.

    Jang Eun Lee

    Full Text Available Differentiation of T cells is closely associated with dynamic changes in nutrient and energy metabolism. However, the extent to which specific metabolic pathways and molecular components are determinative of CD8+ T cell fate remains unclear. It has been previously established in various tissues that acetyl CoA carboxylase 2 (ACC2 regulates fatty acid oxidation (FAO by inhibiting carnitine palmitoyltransferase 1 (CPT1, a rate-limiting enzyme of FAO in mitochondria. Here, we explore the cell-intrinsic role of ACC2 in T cell immunity in response to infections. We report here that ACC2 deficiency results in a marginal increase of cellular FAO in CD8+ T cells, but does not appear to influence antigen-specific effector and memory CD8+ T cell responses during infection with listeria or lymphocytic choriomeningitis virus. These results suggest that ACC2 is dispensable for CD8+ T cell responses.

  19. Inhibiting glycolytic metabolism enhances CD8+ T cell memory and antitumor function

    Sukumar, Madhusudhanan; Liu, Jie; Ji, Yun; Subramanian, Murugan; Crompton, Joseph G.; Yu, Zhiya; Roychoudhuri, Rahul; Palmer, Douglas C.; Muranski, Pawel; Karoly, Edward D.; Mohney, Robert P.; Klebanoff, Christopher A.; Lal, Ashish; Finkel, Toren; Restifo, Nicholas P.; Gattinoni, Luca


    Naive CD8+ T cells rely upon oxidation of fatty acids as a primary source of energy. After antigen encounter, T cells shift to a glycolytic metabolism to sustain effector function. It is unclear, however, whether changes in glucose metabolism ultimately influence the ability of activated T cells to become long-lived memory cells. We used a fluorescent glucose analog, 2-NBDG, to quantify glucose uptake in activated CD8+ T cells. We found that cells exhibiting limited glucose incorporation had a molecular profile characteristic of memory precursor cells and an increased capacity to enter the memory pool compared with cells taking up high amounts of glucose. Accordingly, enforcing glycolytic metabolism by overexpressing the glycolytic enzyme phosphoglycerate mutase-1 severely impaired the ability of CD8+ T cells to form long-term memory. Conversely, activation of CD8+ T cells in the presence of an inhibitor of glycolysis, 2-deoxyglucose, enhanced the generation of memory cells and antitumor functionality. Our data indicate that augmenting glycolytic flux drives CD8+ T cells toward a terminally differentiated state, while its inhibition preserves the formation of long-lived memory CD8+ T cells. These results have important implications for improving the efficacy of T cell–based therapies against chronic infectious diseases and cancer. PMID:24091329

  20. Antigen and Memory CD8 T Cells: Were They Both Right?

    Epelman Slava


    Full Text Available Picture yourself as a researcher in immunology. To begin your project, you ask a question: Do CD8 T cells require antigen to maintain a memory response? This question is of prime importance to numerous medical fields. In chronologic order, you digest the literature, but unfortunately, you hit a major stumbling block in the 1990s. The crux of the problem is that which so often happens in science: two well-recognized, capable groups emerge with diametrically opposed conclusions, leaving you pondering which set of wellcontrolled data to believe. Fortunately, years later, a surprising group of articles sheds light on this mystery and subtly reconciles these two positions.

  1. Human mesenchymal stem cells are susceptible to lysis by CD8(+) T cells and NK cells.

    Crop, Meindert J; Korevaar, Sander S; de Kuiper, Ronella; IJzermans, Jan N M; van Besouw, Nicole M; Baan, Carla C; Weimar, Willem; Hoogduijn, Martin J


    There is growing interest in the use of mesenchymal stem cells (MSCs) to improve the outcome of organ transplantation. The immunogenicity of MSCs is, however, unclear and is important for the efficacy of MSC therapy and for potential sensitization against donor antigens. We investigated the susceptibility of autologous and allogeneic MSCs for lysis by CD8(+) T-lymphocytes and NK cells in a kidney transplant setting. MSCs were derived from adipose tissue of human kidney donors and were CD90(+), CD105(+), CD166(+), and HLA class I(+). They showed differentiation ability and immunosuppressive capacity. Lysis of MSCs by peripheral blood mononuclear cells (PBMCs), FACS-sorted CD8(+) T cells, and NK cells was measured by europium release assay. Allogeneic MSCs were susceptible for lysis by cytotoxic CD8(+) T cells and NK cells, while autologous MSCs were lysed by NK cells only. NK cell-mediated lysis was inversely correlated with the expression of HLA class I on MSCs. Lysis of autologous MSCs was not dependent on culturing of MSCs in FBS, and MSCs in suspension as well as adherent to plastic were lysed by NK cells. Pretransplant recipient PBMCs did not lyse donor MSCs, but PBMCs isolated 3, 6, and 12 months after transplantation showed increasing lysing ability. After 12 months, CD8(+) T-cell-mediated lysis of donor MSCs persisted, indicating there was no evidence for desensitization against donor MSCs. Lysis of MSCs is important to take into account when MSCs are considered for clinical application. Our results suggest that the HLA background of MSCs and timing of MSC administration are important for the efficacy of MSC therapy. PMID:21396164

  2. Cish actively silences TCR signaling in CD8+ T cells to maintain tumor tolerance

    Douglas C Palmer; Guittard, Geoffrey C.; Franco, Zulmarie; Crompton, Joseph G.; Eil, Robert L; Patel, Shashank J.; Ji, Yun; van Panhuys, Nicholas; Klebanoff, Christopher A.; Sukumar, Madhusudhanan; Clever, David; Chichura, Anna; Roychoudhuri, Rahul; Varma, Rajat; Wang, Ena


    Improving the functional avidity of effector T cells is critical in overcoming inhibitory factors within the tumor microenvironment and eliciting tumor regression. We have found that Cish, a member of the suppressor of cytokine signaling (SOCS) family, is induced by TCR stimulation in CD8+ T cells and inhibits their functional avidity against tumors. Genetic deletion of Cish in CD8+ T cells enhances their expansion, functional avidity, and cytokine polyfunctionality, resulting in pronounced a...

  3. Specific immunotherapy generates CD8(+) CD196(+) T cells to suppress lung cancer growth in mice.

    Zhang, Jian; Liu, Jing; Chen, Huiguo; Wu, Weibin; Li, Xiaojun; Wu, Yonghui; Wang, Zhigang; Zhang, Kai; Li, Yun; Weng, Yimin; Liao, Hongying; Gu, Lijia


    That specific immunotherapy can inhibit cancer growth has been recognized; its efficiency is to be improved. This study aimed to inhibit lung cancer (LC) growth in a mouse model by using an LC-specific vaccination. In this study, a LC mouse model was created by adoptive transplantation with LC cells. The tumor-bearing mice were vaccinated with LC cell extracts plus adjuvant TNBS or adoptive transplantation with specific CD8(+) CD196(+) T cells. The results showed that the vaccination with LC extracts (LCE)/TNBS markedly inhibited the LC growth and induced CD8(+) CD196(+) T cells in LC tissue and the spleen. These CD8(+) CD196(+) T cells proliferated and produce high levels of perforin upon exposure to LCE and specifically induced LC cell apoptosis. Exposure to TNBS induced RAW264.7 cells to produce macrophage inflammatory protein-3α; the latter activated signal transducer and activator of transcription 3 and further induced perforin expression in the CD8(+) CD196(+) T cells. Adoptive transfer with specific CD8(+) CD196(+) T cells suppressed LC growth in mice. In conclusion, immunization with LC extracts and TNBS can induce LC-specific CD8(+) CD196(+) T cells in LC-bearing mice and inhibit LC growth. PMID:26910585

  4. Natural killer cells promote early CD8 T cell responses against cytomegalovirus.

    Scott H Robbins


    Full Text Available Understanding the mechanisms that help promote protective immune responses to pathogens is a major challenge in biomedical research and an important goal for the design of innovative therapeutic or vaccination strategies. While natural killer (NK cells can directly contribute to the control of viral replication, whether, and how, they may help orchestrate global antiviral defense is largely unknown. To address this question, we took advantage of the well-defined molecular interactions involved in the recognition of mouse cytomegalovirus (MCMV by NK cells. By using congenic or mutant mice and wild-type versus genetically engineered viruses, we examined the consequences on antiviral CD8 T cell responses of specific defects in the ability of the NK cells to control MCMV. This system allowed us to demonstrate, to our knowledge for the first time, that NK cells accelerate CD8 T cell responses against a viral infection in vivo. Moreover, we identify the underlying mechanism as the ability of NK cells to limit IFN-alpha/beta production to levels not immunosuppressive to the host. This is achieved through the early control of cytomegalovirus, which dramatically reduces the activation of plasmacytoid dendritic cells (pDCs for cytokine production, preserves the conventional dendritic cell (cDC compartment, and accelerates antiviral CD8 T cell responses. Conversely, exogenous IFN-alpha administration in resistant animals ablates cDCs and delays CD8 T cell activation in the face of NK cell control of viral replication. Collectively, our data demonstrate that the ability of NK cells to respond very early to cytomegalovirus infection critically contributes to balance the intensity of other innate immune responses, which dampens early immunopathology and promotes optimal initiation of antiviral CD8 T cell responses. Thus, the extent to which NK cell responses benefit the host goes beyond their direct antiviral effects and extends to the prevention of innate

  5. Host and viral factors contributing to CD8+ T cell failure in hepatitis C virus infection

    Christoph Neumann-Haefelin; Hans Christian Spangenberg; Hubert E Blum; Robert Thimme


    Virus-specific CD8+ T cells are thought to be the major anti-viral effector cells in hepatitis C virus (HCV)infection. Indeed, viral clearance is associated with vigorous CD8+ T cell responses targeting multiple epitopes. In the chronic phase of infection, HCV-specific CD8+ T cell responses are usually weak, narrowly focused and display often functional defects regarding cytotoxicity, cytokine production, and proliferative capacity. In the last few years, different mechanisms which might contribute to the failure of HCV-specific CD8+ T cells in chronic infection have been identified,including insufficient CD4+ help, deficient CD8+ T cell differentiation, viral escape mutations, suppression by viral factors, inhibitory cytokines, inhibitory ligands, and regulatory T cells. In addition, host genetic factors such as the host's human leukocyte antigen (HLA) background may play an important role in the efficiency of the HCVspecific CD8+ T cell response and thus outcome of infection. The growing understanding of the mechanisms contributing to T cell failure and persistence of HCV infection will contribute to the development of successful immunotherapeutical and -prophylactical strategies.

  6. Neonatal CD8+ T-cell differentiation is dependent on interleukin-12.

    McCarron, Mark J


    Neonatal CD8(+) T-cell activation is significantly impaired compared with that in adults. Recent studies have demonstrated that interleukin (IL)-12 is necessary as a third signal, in addition to antigen and co-stimulation, to authorize the differentiation of naive CD8(+) T cells. We examined whether human neonatal CD8(+) T cells, which possess an exclusively naive T-cell phenotype, required a third signal to authorize a productive T-cell response. IL-12 enhanced activated naive CD8(+) T-cell survival, expansion, CD25 expression, and IL-2 production. Activated CD8(+) T cells produced interferon-gamma and intracellular granzyme B and were cytotoxic only in the presence of IL-12. Sustained IL-12 signaling for 72 hours was required for optimal interferon-gamma production. IL-12, in concert with T cell receptor (TCR) stimulation, sustained late-stage (48-72 hours) intracellular phosphorylation and particularly total protein levels of the proximal TCR components, Lck, and CD3xi. The requirement for a third signal for productive human neonatal CD8(+) T-cell differentiation may have implications for neonatal vaccination strategies.

  7. Perforin-deficient CD8+ T cells mediate fatal lymphocytic choriomeningitis despite impaired cytokine production

    Storm, Pernille; Bartholdy, Christina; Sørensen, Maria Rathmann; Christensen, Jan Pravsgaard; Thomsen, Allan Randrup


    the outcome of i.c. infection with LCMV. We confirmed that the expansion of virus-specific CD8(+) T cells is unimpaired in perforin-deficient mice. However, despite the fact that the virus-specific CD8(+) effector T cells in perforin-deficient mice are broadly impaired in their effector function......, these mice invariably succumb to i.c. infection with LCMV strain Armstrong, although a few days later than matched wild-type mice. Upon further investigation, we found that this delay correlates with the delayed recruitment of inflammatory cells to the central nervous system (CNS). However, CD8...... the main explanation for the delayed onset of fatal disease in perforin-deficient mice. However, once accumulated in the CNS, virus-specific CD8(+) T cells can induce fatal CNS pathology despite the absence of perforin-mediated lysis and reduced capacity to produce several key cytokines....

  8. Label Free Detection of CD4+ and CD8+ T Cells Using the Optofluidic Ring Resonator

    John T. Gohring


    Full Text Available We have demonstrated label free detection of CD4+ and CD8+ T-Lymphocyte whole cells and CD4+ T-Lymphocyte cell lysis using the optofluidic ring resonator (OFRR sensor. The OFRR sensing platform incorporates microfluidics and photonics in a setup that utilizes small sample volume and achieves a fast detection time. In this work, white blood cells were isolated from healthy blood and the concentrations were adjusted to match T-Lymphocyte levels of individuals infected with HIV. Detection was accomplished by immobilizing CD4 and CD8 antibodies on the inner surface of the OFRR. Sensing results show excellent detection of CD4+ and CD8+ T-Lymphocyte cells at medically significant concentrations with a detection time of approximately 30 minutes. This work will lead to a rapid and low-cost sensing device that can provide a CD4 and CD8 count as a measure of HIV progression.

  9. CD8+ T cell activation correlates with disease activity in clinically isolated syndromes and is regulated by interferon-beta treatment

    Jensen, J; Sellebjerg, Finn Thorup; Langkilde, A; Frederiksen, Jette Lautrup Battistini

    An increased percentage of blood CD8+ T cells from patients with clinically isolated syndromes (CIS) suggestive of multiple sclerosis (MS) was found to express CD26 and CD69. The percentage of CD26 or CD69 positive CD8+ T cells was higher in patients with MRI evidence of disease dissemination in...... space or with active MRI lesions than in the remaining patients. Treatment of MS with interferon (IFN)-beta resulted in a decrease in the percentage of CD26 and CD71 positive CD8+ T cells and an increase in the percentage of CD8+ T cells that expressed interleukin (IL)-10 and IL-13. CD8+ T cell...

  10. Enumeration of CD4 and CD8 T-cells in HIV infection in Zimbabwe using a manual immunocytochemical method

    Gomo, E; Ndhlovu, P; Vennervald, B J; Nyazema, N; Friis, Henrik


    OBJECTIVES: To enumerate CD4 and CD8 T-cells using the simple and cheap immuno-alkaline phosphatase (IA) method and to compare it with flow cytometry (FC); and to study the effects of duration of sample storage on the IA method results. DESIGN: Method comparison study. SETTING: Blair Research...... Laboratory, Harare, Zimbabwe. SUBJECTS: 41 HIV positive and 11 HIV negative men and women from Harare participating in HIV studies at Blair Research Laboratory, Zimbabwe. MAIN OUTCOME MEASURES: CD4 and CD8 T-cell counts by FC and the IA method. RESULTS: The IA method and FC were highly correlated for CD4...... counts (Spearman rs = 0.91), CD4 percentage (rs = 0.84), CD8 count (rs = 0.83), CD8 percentage (rs = 0.96) and CD4/CD8 ratio (rs = 0.89). However, CD4 cell counts and percentage measured by the IA method were (mean difference +/- SE) 133 +/- 24 cells/microL [corrected] and 6.7 +/- 1.1% higher than those...

  11. Kinetics and Phenotype of Vaccine-Induced CD8+ T-Cell Responses to Toxoplasma gondii▿

    Jordan, Kimberly A.; Wilson, Emma H.; Tait, Elia D.; Fox, Barbara A.; Roos, David S.; Bzik, David J.; Dzierszinski, Florence; Hunter, Christopher A.


    Multiple studies have established that the ability of CD8+ T cells to act as cytolytic effectors and produce gamma interferon is important in mediating resistance to the intracellular parasite Toxoplasma gondii. To better understand the generation of the antigen-specific CD8+ T-cell responses induced by T. gondii, mice were immunized with replication-deficient parasites that express the model antigen ovalbumin (OVA). Class I tetramers specific for SIINFEKL were used to track the OVA-specific ...

  12. Biopolymer encapsulated live influenza virus as a universal CD8+ T cell vaccine against influenza virus

    Boesteanu, Alina C.; Babu, Nadarajan S.; Wheatley, Margaret; Papazoglou, Elisabeth S.; Katsikis, Peter D.


    Current influenza virus vaccines primarily elicit antibodies and can be rendered ineffective by antigenic drift and shift. Vaccines that elicit CD8+ T cell responses targeting less variable proteins may function as universal vaccines that have broad reactivity against different influenza virus strains. To generate such a universal vaccine, we encapsulated live influenza virus in a biopolymer and delivered it to mice subcutaneously. This vaccine was safe, induced potent CD8+ T cell immunity an...

  13. CD8{sup +}CD25{sup +} T cells reduce atherosclerosis in apoE(−/−) mice

    Zhou, Jianchang; Dimayuga, Paul C.; Zhao, Xiaoning; Yano, Juliana; Lio, Wai Man; Trinidad, Portia; Honjo, Tomoyuki; Cercek, Bojan; Shah, Prediman K.; Chyu, Kuang-Yuh, E-mail:


    Highlights: •The role of a sub-population of CD8{sup +} T cells with suppressor functions was investigated in atherosclerosis. •CD8{sup +}CD25{sup +} T cells from adult apoE(−/−) mice had phenotype characteristics of T suppressor cells. •These CD8{sup +}CD25{sup +} T cells reduced CD4{sup +} T cell proliferation and CD8{sup +} cytotoxic activity in vitro. •Adoptive transfer of CD8{sup +}CD25{sup +} T cells significantly reduced atherosclerosis. •CD8{sup +}CD25{sup +} T cells have a suppressive function in atherosclerosis. -- Abstract: Background: It is increasingly evident that CD8{sup +} T cells are involved in atherosclerosis but the specific subtypes have yet to be defined. CD8{sup +}CD25{sup +} T cells exert suppressive effects on immune signaling and modulate experimental autoimmune disorders but their role in atherosclerosis remains to be determined. The phenotype and functional role of CD8{sup +}CD25{sup +} T cells in experimental atherosclerosis were investigated in this study. Methods and results: CD8{sup +}CD25{sup +} T cells were observed in atherosclerotic plaques of apoE(−/−) mice fed hypercholesterolemic diet. Characterization by flow cytometric analysis and functional evaluation using a CFSE-based proliferation assays revealed a suppressive phenotype and function of splenic CD8{sup +}CD25{sup +} T cells from apoE(−/−) mice. Depletion of CD8{sup +}CD25{sup +} from total CD8{sup +} T cells rendered higher cytolytic activity of the remaining CD8{sup +}CD25{sup −} T cells. Adoptive transfer of CD8{sup +}CD25{sup +} T cells into apoE(−/−) mice suppressed the proliferation of splenic CD4{sup +} T cells and significantly reduced atherosclerosis in recipient mice. Conclusions: Our study has identified an athero-protective role for CD8{sup +}CD25{sup +} T cells in experimental atherosclerosis.

  14. CD8+ cell noncytotoxic antiviral response (CNAR) to HIV in nosocomial HIV-infected individuals%医源性HIV感染者CD8+细胞非细胞毒性HIV抑制作用的研究

    袁霖; 马丽英; 臧希卉; 孟向东; 彭虹; 赵全壁; 邢辉; 邵一鸣


    Objective To study the CD8+ cell noncytotoxic antiviral response (CNAR) to HIV in nosocomial HIV infected individuals, and reveal the relationship between the CNAR and CD4 cell count. MethodCD8+ cells from HIV-1 sero-positive individuals were separated by immunomagnetic beads and mixed withCD4+ cells at different CD8 CD4 cell input ratios (2:1,1:1,0.5:1 and 0.25:1). Reverse transcriptase (RT) activity of cocultured supernatant was tested and compared with negative control and the suppression rate of HIV-1 replication was measured. Result The average CD8 : CD4 cell input ratios to reach 80% suppression of HIV replication in the group with CD4300/μl were 2.4:1 and 1.3:1, respectively (P cell count. The ability to suppress HIV replication in subjects with CD4>300 is stronger than those with CD4300个/μl组的平均CD8与CD4比例为1.3:1,两组间比较差异有统计学意义(P300的个体较CD4<300的个体有着更显著的抑制HIV复制的能力.

  15. Differential sensitivity of naive and memory CD8+ T cells to apoptosis in vivo.

    Grayson, Jason M; Harrington, Laurie E; Lanier, J Gibson; Wherry, E John; Ahmed, Rafi


    Apoptosis is a critical regulator of homeostasis in the immune system. In this study we demonstrate that memory CD8(+) T cells are more resistant to apoptosis than naive cells. After whole body irradiation of mice, both naive and memory CD8(+) T cells decreased in number, but the reduction in the number of naive cells was 8-fold greater than that in memory CD8(+) T cells. In addition to examining radiation-induced apoptosis, we analyzed the expansion and contraction of naive and memory CD8(+) T cells in vivo following exposure to Ag. We found that memory CD8(+) T cells not only responded more quickly than naive cells after viral infection, but that secondary effector cells generated from memory cells underwent much less contraction compared with primary effectors generated from naive cells (3- to 5-fold vs 10- to 20-fold decrease). Increased numbers of secondary memory cells were observed in both lymphoid and non-lymphoid tissues. When naive and memory cells were transferred into the same animal, secondary effectors underwent less contraction than primary effector cells. These experiments analyzing apoptosis of primary and secondary effectors in the same animal show unequivocally that decreased downsizing of the secondary response reflects an intrinsic property of the memory T cells and is not simply due to environmental effects. These findings have implications for designing prime/boost vaccine strategies and also for optimizing immunotherapeutic regimens for treatment of chronic infections. PMID:12244170

  16. CD8+ CD205+ splenic dendritic cells are specialized to induce Foxp3+ regulatory T cells.

    Yamazaki, Sayuri; Dudziak, Diana; Heidkamp, Gordon F; Fiorese, Christopher; Bonito, Anthony J; Inaba, Kayo; Nussenzweig, Michel C; Steinman, Ralph M


    Foxp3(+)CD25(+)CD4(+) regulatory T cells (Treg) mediate immunological self-tolerance and suppress immune responses. A subset of dendritic cells (DCs) in the intestine is specialized to induce Treg in a TGF-beta- and retinoic acid-dependent manner to allow for oral tolerance. In this study we compare two major DC subsets from mouse spleen. We find that CD8(+) DEC-205/CD205(+) DCs, but not the major fraction of CD8(-) DC inhibitory receptor-2 (DCIR2)(+) DCs, induce functional Foxp3(+) Treg from Foxp3(-) precursors in the presence of low doses of Ag but without added TGF-beta. CD8(+)CD205(+) DCs preferentially express TGF-beta, and the induction of Treg by these DCs in vitro is blocked by neutralizing Ab to TGF-beta. In contrast, CD8(-)DCIR2(+) DCs better induce Foxp3(+) Treg when exogenous TGF-beta is supplied. In vivo, CD8(+)CD205(+) DCs likewise preferentially induce Treg from adoptively transferred, Ag-specific DO11.10 RAG(-/-) Foxp3(-)CD4(+) T cells, whereas the CD8(-)DCIR2(+) DCs better stimulate natural Foxp3(+) Treg. These results indicate that a subset of DCs in spleen, a systemic lymphoid organ, is specialized to differentiate peripheral Foxp3(+) Treg, in part through the endogenous formation of TGF-beta. Targeting of Ag to these DCs might be useful for inducing Ag-specific Foxp3(+) Treg for treatment of autoimmune diseases, transplant rejection, and allergy. PMID:18981112

  17. Phenotypic and Functional Alterations in Circulating Memory CD8 T Cells with Time after Primary Infection.

    Matthew D Martin


    Full Text Available Memory CD8 T cells confer increased protection to immune hosts upon secondary viral, bacterial, and parasitic infections. The level of protection provided depends on the numbers, quality (functional ability, and location of memory CD8 T cells present at the time of infection. While primary memory CD8 T cells can be maintained for the life of the host, the full extent of phenotypic and functional changes that occur over time after initial antigen encounter remains poorly characterized. Here we show that critical properties of circulating primary memory CD8 T cells, including location, phenotype, cytokine production, maintenance, secondary proliferation, secondary memory generation potential, and mitochondrial function change with time after infection. Interestingly, phenotypic and functional alterations in the memory population are not due solely to shifts in the ratio of effector (CD62Llo and central memory (CD62Lhi cells, but also occur within defined CD62Lhi memory CD8 T cell subsets. CD62Lhi memory cells retain the ability to efficiently produce cytokines with time after infection. However, while it is was not formally tested whether changes in CD62Lhi memory CD8 T cells over time occur in a cell intrinsic manner or are due to selective death and/or survival, the gene expression profiles of CD62Lhi memory CD8 T cells change, phenotypic heterogeneity decreases, and mitochondrial function and proliferative capacity in either a lymphopenic environment or in response to antigen re-encounter increase with time. Importantly, and in accordance with their enhanced proliferative and metabolic capabilities, protection provided against chronic LCMV clone-13 infection increases over time for both circulating memory CD8 T cell populations and for CD62Lhi memory cells. Taken together, the data in this study reveal that memory CD8 T cells continue to change with time after infection and suggest that the outcome of vaccination strategies designed to elicit

  18. Visualizing early splenic memory CD8+ T cells reactivation against intracellular bacteria in the mouse.

    Marc Bajénoff

    Full Text Available Memory CD8(+ T cells represent an important effector arm of the immune response in maintaining long-lived protective immunity against viruses and some intracellular bacteria such as Listeria monocytogenes (L.m. Memory CD8(+ T cells are endowed with enhanced antimicrobial effector functions that perfectly tail them to rapidly eradicate invading pathogens. It is largely accepted that these functions are sufficient to explain how memory CD8(+ T cells can mediate rapid protection. However, it is important to point out that such improved functional features would be useless if memory cells were unable to rapidly find the pathogen loaded/infected cells within the infected organ. Growing evidences suggest that the anatomy of secondary lymphoid organs (SLOs fosters the cellular interactions required to initiate naive adaptive immune responses. However, very little is known on how the SLOs structures regulate memory immune responses. Using Listeria monocytogenes (L.m as a murine infection model and imaging techniques, we have investigated if and how the architecture of the spleen plays a role in the reactivation of memory CD8(+ T cells and the subsequent control of L.m growth. We observed that in the mouse, memory CD8(+ T cells start to control L.m burden 6 hours after the challenge infection. At this very early time point, L.m-specific and non-specific memory CD8(+ T cells localize in the splenic red pulp and form clusters around L.m infected cells while naïve CD8(+ T cells remain in the white pulp. Within these clusters that only last few hours, memory CD8(+ T produce inflammatory cytokines such as IFN-gamma and CCL3 nearby infected myeloid cells known to be crucial for L.m killing. Altogether, we describe how memory CD8(+ T cells trafficking properties and the splenic micro-anatomy conjugate to create a spatio-temporal window during which memory CD8(+ T cells provide a local response by secreting effector molecules around infected cells.

  19. Differential remodeling of a T-cell transcriptome following CD8-versus CD3-induced signaling

    S Hussain I Abidi; Tao Dong; Mai T Vuong; Vattipally B Sreenu; Sarah L Rowland-Jones; Edward J Evans; Simon J Davis


    CD8 engagement with class I major histocompatibility antigens greatly enhances T-cell activation,but it is not clear how this is achieved.We address the question of whether or not the antibody-mediated ligation of CD8 alone induces transcriptional remodeling in a T-cell clone,using serial analysis of gene expression.Even though it fails to induce overt phenotypic changes,we find that CD8 ligation profoundly alters transcription in the T-cell clone,at a scale comparable to that induced by antibody-mediated ligation of CD3.The character of the resulting changes is distinct,however,with the net effect ofCD8 ligation being substantially inhibitory.We speculate that ligating CD8 induces weak,T-cell receptor (TCR)-mediated inhibitory signals reminiscent of the effects of TCR antagonists.Our results imply that CD8 ligation alone is incapable of activating the T-cell clone because it fails to fully induce NFAT-dependent transcription.

  20. HIV-Specific CD8+ T Cell-Mediated Viral Suppression Correlates With the Expression of CD57

    Jensen, Sanne S; Tingstedt, Jeanette Linnea; Larsen, Tine Kochendorf;


    BACKGROUND: Virus-specific CD8(+) T-cell responses are believed to play an important role in the control of HIV-1 infection; however, what constitutes an effective HIV-1 CD8(+) T-cell response remains a topic of debate. The ex vivo viral suppressive capacity was measured of CD8(+) T cells from 44...

  1. Kinetics and phenotype of vaccine-induced CD8+ T-cell responses to Toxoplasma gondii.

    Jordan, Kimberly A; Wilson, Emma H; Tait, Elia D; Fox, Barbara A; Roos, David S; Bzik, David J; Dzierszinski, Florence; Hunter, Christopher A


    Multiple studies have established that the ability of CD8(+) T cells to act as cytolytic effectors and produce gamma interferon is important in mediating resistance to the intracellular parasite Toxoplasma gondii. To better understand the generation of the antigen-specific CD8(+) T-cell responses induced by T. gondii, mice were immunized with replication-deficient parasites that express the model antigen ovalbumin (OVA). Class I tetramers specific for SIINFEKL were used to track the OVA-specific endogenous CD8(+) T cells. The peak CD8(+) T-cell response was found at day 10 postimmunization, after which the frequency and numbers of antigen-specific cells declined. Unexpectedly, replication-deficient parasites were found to induce antigen-specific cells with faster kinetics than replicating parasites. The generation of optimal numbers of antigen-specific CD8(+) effector T cells was found to require CD4(+) T-cell help. At 7 days following immunization, antigen-specific cells were found to be CD62L(low), KLRG1(+), and CD127(low), and they maintained this phenotype for more than 70 days. Antigen-specific CD8(+) effector T cells in immunized mice exhibited potent perforin-dependent OVA-specific cytolytic activity in vivo. Perforin-dependent cytolysis appeared to be the major cytolytic mechanism; however, a perforin-independent pathway that was not mediated via Fas-FasL was also detected. This study provides further insight into vaccine-induced cytotoxic T-lymphocyte responses that correlate with protective immunity to T. gondii and identifies a critical role for CD4(+) T cells in the generation of protective CD8(+) T-cell responses. PMID:19528214

  2. Kinetics and Phenotype of Vaccine-Induced CD8+ T-Cell Responses to Toxoplasma gondii▿

    Jordan, Kimberly A.; Wilson, Emma H.; Tait, Elia D.; Fox, Barbara A.; Roos, David S.; Bzik, David J.; Dzierszinski, Florence; Hunter, Christopher A.


    Multiple studies have established that the ability of CD8+ T cells to act as cytolytic effectors and produce gamma interferon is important in mediating resistance to the intracellular parasite Toxoplasma gondii. To better understand the generation of the antigen-specific CD8+ T-cell responses induced by T. gondii, mice were immunized with replication-deficient parasites that express the model antigen ovalbumin (OVA). Class I tetramers specific for SIINFEKL were used to track the OVA-specific endogenous CD8+ T cells. The peak CD8+ T-cell response was found at day 10 postimmunization, after which the frequency and numbers of antigen-specific cells declined. Unexpectedly, replication-deficient parasites were found to induce antigen-specific cells with faster kinetics than replicating parasites. The generation of optimal numbers of antigen-specific CD8+ effector T cells was found to require CD4+ T-cell help. At 7 days following immunization, antigen-specific cells were found to be CD62Llow, KLRG1+, and CD127low, and they maintained this phenotype for more than 70 days. Antigen-specific CD8+ effector T cells in immunized mice exhibited potent perforin-dependent OVA-specific cytolytic activity in vivo. Perforin-dependent cytolysis appeared to be the major cytolytic mechanism; however, a perforin-independent pathway that was not mediated via Fas-FasL was also detected. This study provides further insight into vaccine-induced cytotoxic T-lymphocyte responses that correlate with protective immunity to T. gondii and identifies a critical role for CD4+ T cells in the generation of protective CD8+ T-cell responses. PMID:19528214

  3. A Gene Expression Signature That Correlates with CD8+ T Cell Expansion in Acute EBV Infection.

    Greenough, Thomas C; Straubhaar, Juerg R; Kamga, Larisa; Weiss, Eric R; Brody, Robin M; McManus, Margaret M; Lambrecht, Linda K; Somasundaran, Mohan; Luzuriaga, Katherine F


    Virus-specific CD8(+) T cells expand dramatically during acute EBV infection, and their persistence is important for lifelong control of EBV-related disease. To better define the generation and maintenance of these effective CD8(+) T cell responses, we used microarrays to characterize gene expression in total and EBV-specific CD8(+) T cells isolated from the peripheral blood of 10 individuals followed from acute infectious mononucleosis (AIM) into convalescence (CONV). In total CD8(+) T cells, differential expression of genes in AIM and CONV was most pronounced among those encoding proteins important in T cell activation/differentiation, cell division/metabolism, chemokines/cytokines and receptors, signaling and transcription factors (TF), immune effector functions, and negative regulators. Within these categories, we identified 28 genes that correlated with CD8(+) T cell expansion in response to an acute EBV infection. In EBV-specific CD8(+) T cells, we identified 33 genes that were differentially expressed in AIM and CONV. Two important TF, T-bet and eomesodermin, were upregulated and maintained at similar levels in both AIM and CONV; in contrast, protein expression declined from AIM to CONV. Expression of these TF varied among cells with different epitope specificities. Collectively, gene and protein expression patterns suggest that a large proportion, if not a majority of CD8(+) T cells in AIM are virus specific, activated, dividing, and primed to exert effector activities. High expression of T-bet and eomesodermin may help to maintain effector mechanisms in activated cells and to enable proliferation and transition to earlier differentiation states in CONV. PMID:26416268

  4. Neuroantigen-specific autoregulatory CD8+ T cells inhibit autoimmune demyelination through modulation of dendritic cell function.

    Venkatesh P Kashi

    Full Text Available Experimental autoimmune encephalomyelitis (EAE is a well-established murine model of multiple sclerosis, an immune-mediated demyelinating disorder of the central nervous system (CNS. We have previously shown that CNS-specific CD8+ T cells (CNS-CD8+ ameliorate EAE, at least in part through modulation of CNS-specific CD4+ T cell responses. In this study, we show that CNS-CD8+ also modulate the function of CD11c+ dendritic cells (DC, but not other APCs such as CD11b+ monocytes or B220+ B cells. DC from mice receiving either myelin oligodendrocyte glycoprotein-specific CD8+ (MOG-CD8+ or proteolipid protein-specific CD8+ (PLP-CD8+ T cells were rendered inefficient in priming T cell responses from naïve CD4+ T cells (OT-II or supporting recall responses from CNS-specific CD4+ T cells. CNS-CD8+ did not alter DC subset distribution or MHC class II and CD86 expression, suggesting that DC maturation was not affected. However, the cytokine profile of DC from CNS-CD8+ recipients showed lower IL-12 and higher IL-10 production. These functions were not modulated in the absence of immunization with CD8-cognate antigen, suggesting an antigen-specific mechanism likely requiring CNS-CD8-DC interaction. Interestingly, blockade of IL-10 in vitro rescued CD4+ proliferation and in vivo expression of IL-10 was necessary for the suppression of EAE by MOG-CD8+. These studies demonstrate a complex interplay between CNS-specific CD8+ T cells, DC and pathogenic CD4+ T cells, with important implications for therapeutic interventions in this disease.

  5. Molecular Anatomy and Number of Antigen Specific CD8 T Cells Required to Cause Type 1 Diabetes

    Oldstone, Michael B.A.; Edelmann, Kurt H; McGavern, Dorian B.; Cruite, Justin T.; Welch, Megan J.


    We quantified CD8 T cells needed to cause type 1 diabetes and studied the anatomy of the CD8 T cell/beta (β) cell interaction at the immunologic synapse. We used a transgenic model, in situ tetramer staining to distinguish antigen specific CD8 T cells from total T cells infiltrating islets and a variety of viral mutants selected for functional deletion(s) of various CD8 T cell epitopes. Twenty percent of CD8 T cells in the spleen were specific for all immunodominant and subdominant viral glyc...

  6. The localization of naive and memory CD8+ T cells following infection

    Yang, Edward


    Different subsets of memory CD8⁺ T cells populate the T cell compartment. Antigen-experienced memory (true-memory) cells are formed in a classic immune response against an invading pathogen, but memory-like (HP-memory) cells can also be generated through antigen-independent homeostatic proliferation resulting from lymphopenia. HP-memory cells subsequently acquire the same effector functions and surface marker expression as true-memory cells. When HP- and true-memory CD8cells of the same spe...

  7. Secretion of Interleukin-17 by CD8+ T Cells Expressing CD146 (MCAM)

    Dagur, Pradeep K; Biancotto, Angélique; Stansky, Elena; Sen, H. Nida; Nussenblatt, Robert B.; McCoy, J. Philip


    Interleukin-17 (IL-17) has been associated with the pathogenesis of numerous autoimmune diseases. CD4+ T cells secreting IL-17 are termed Th17 cells. CD8+ T cells, designated Tc17 cells, are also capable of secreting IL-17. Here we describe a population of Tc17 cells characterized by the expression of surface CD146, an endothelial adhesion molecule. These cells display signatures of a human Tc17 genotype and phenotype. Circulating CD8+CD146+ T cells are present in low levels in healthy adults...

  8. Immunological tolerance to muscle autoantigens involves peripheral deletion of autoreactive CD8+ T cells.

    Emilie Franck

    Full Text Available Muscle potentially represents the most abundant source of autoantigens of the body and can be targeted by a variety of severe autoimmune diseases. Yet, the mechanisms of immunological tolerance toward muscle autoantigens remain mostly unknown. We investigated this issue in transgenic SM-Ova mice that express an ovalbumin (Ova neo-autoantigen specifically in skeletal muscle. We previously reported that antigen specific CD4(+ T cell are immunologically ignorant to endogenous Ova in this model but can be stimulated upon immunization. In contrast, Ova-specific CD8(+ T cells were suspected to be either unresponsive to Ova challenge or functionally defective. We now extend our investigations on the mechanisms governing CD8(+ tolerance in SM-Ova mice. We show herein that Ova-specific CD8(+ T cells are not detected upon challenge with strongly immunogenic Ova vaccines even after depletion of regulatory T cells. Ova-specific CD8(+ T cells from OT-I mice adoptively transferred to SM-Ova mice started to proliferate in vivo, acquired CD69 and PD-1 but subsequently down-regulated Bcl-2 and disappeared from the periphery, suggesting a mechanism of peripheral deletion. Peripheral deletion of endogenous Ova-specific cells was formally demonstrated in chimeric SM-Ova mice engrafted with bone marrow cells containing T cell precursors from OT-I TCR-transgenic mice. Thus, the present findings demonstrate that immunological tolerance to muscle autoantigens involves peripheral deletion of autoreactive CD8(+ T cells.

  9. Separate Roles for Antigen Recognition and Lymph Node Inflammation in CD8+ Memory T Cell Formation

    Fransen, Marieke F.; van Stipdonk, Marianne J.; Sluijter, Marjolein; Schoenberger, Stephen P.; Melief, Cornelis J; Offringa, Rienk


    Priming of naive CD8+ T cells by pathogens or vaccines generally involves their interaction with Ag-loaded dendritic cells (DCs) in the context of an inflamed lymph node. Lymph node activation fosters DC and T cell encounters and subsequently provides newly primed T cells with nurturing conditions. We dissected these two aspects by infusing in vitro primed CD8+ T cells into naive recipient mice harboring a single activated lymph node and comparing the fate of these T cells with those infused ...

  10. Temporary, but Essential Requirement of CD8+ T Cells Early in the Pathogenesis of Diabetes in BB Rats as Revealed by Thymectomy and CD8 Depletion

    Jan Rozing


    Full Text Available Autoimmunity-prone BB rats demonstrate a T lymphocytopenia and abnormal T cell subset distribution. To test whether the life span of all T cells or only of certain subsets is reduced in BB rats, we thymectomised 8-week-old BB and PVG rats and subsequently assessed size and composition of the T cell population over a 6-week-period. In both strains, thymectomy (Tx was followed by a decrease in peripheral T cell numbers, which was proportionally larger in BB rats. The decline of the Thy-1+ recent thymic migrant (RTM T cell phenotype was similar in both strains. BB rats showed a rapid preferential loss of CD8+ and CD45RC+ T cells, whereas the relative loss of RT6+ T cells was proportional to that of all T cells and not significantly different from that in PVG rats. Tx at 8-week did not prevent diabetes. Tx of 4-week-old BB rats revealed essentially the same changes in peripheral T cell subset distribution as in 8-week-old animals. However, Tx at week 4 did prevent diabetes. Since this raised the possibility of a temporary requirement of CD8+ T cells for the development of diabetes, we performed CD8 depletions during different pre-diabetic intervals. We found that CD8 depletion from 4 to 8 and 4 to 14 weeks, but not from 8 to 14 weeks of age prevented diabetes. We conclude that the protective effect of early adult Tx is, at least in part, due to the rapid loss of CD8+ T cells, and that these cells are only required between 4 and 8 weeks of age for diabetes to develop in BB rats.

  11. TGF-β and IL-21 cooperatively stimulate activated CD8(+) T cells to differentiate into Tc17 cells.

    Chen, Hsin-Wei; Tsai, Jy-Ping; Yao, Tsung-You; Hsieh, Chia-Ling; Chen, I-Hua; Liu, Shin-Jen


    TGF-β together with IL-21 or IL-6 can drive the differentiation of naïve CD8(+) T cells into IL-17-producing CD8(+) T cells. These IL-17-producing CD8(+) T cells are termed Tc17 cells. Tc17 cells preserve plasticity under various conditions in vitro and in vivo. IFN-γ-producing CD8(+) T cells are termed Tc1 cells. However, Tc1 cells are considered relatively stable. In the present study, we show that the combination of TGF-β plus IL-21, but not IL-6, converts Tc1 cells into Tc17 cells; this conversion is associated with elevated RORα, RORγt, and Batf mRNA levels. These results indicate that Tc1 cells are skewed to the Tc17 cell phenotype under TGF-β plus IL-21-polarizing conditions. Furthermore, IL-6R is expressed on naïve, but not activated, CD8(+) T cells. In contrast, IL-21R is expressed on both naïve and activated CD8(+) T cells. Thus, differential expression profiles of IL-6R and IL-21R on naïve and activated CD8(+) T cells may be one mechanism by which TGF-β plus IL-21, but not IL-6, can drive activated CD8(+) T cells to differentiate into IL-17-producing cells. Taken together, these results provide a novel viewpoint for the plasticity of Tc1 cells. PMID:27085379

  12. Memory CD8(+) T Cells Require Increased Concentrations of Acetate Induced by Stress for Optimal Function.

    Balmer, Maria L; Ma, Eric H; Bantug, Glenn R; Grählert, Jasmin; Pfister, Simona; Glatter, Timo; Jauch, Annaïse; Dimeloe, Sarah; Slack, Emma; Dehio, Philippe; Krzyzaniak, Magdalena A; King, Carolyn G; Burgener, Anne-Valérie; Fischer, Marco; Develioglu, Leyla; Belle, Réka; Recher, Mike; Bonilla, Weldy V; Macpherson, Andrew J; Hapfelmeier, Siegfried; Jones, Russell G; Hess, Christoph


    How systemic metabolic alterations during acute infections impact immune cell function remains poorly understood. We found that acetate accumulates in the serum within hours of systemic bacterial infections and that these increased acetate concentrations are required for optimal memory CD8(+) T cell function in vitro and in vivo. Mechanistically, upon uptake by memory CD8(+) T cells, stress levels of acetate expanded the cellular acetyl-coenzyme A pool via ATP citrate lyase and promoted acetylation of the enzyme GAPDH. This context-dependent post-translational modification enhanced GAPDH activity, catalyzing glycolysis and thus boosting rapid memory CD8(+) T cell responses. Accordingly, in a murine Listeria monocytogenes model, transfer of acetate-augmented memory CD8(+) T cells exerted superior immune control compared to control cells. Our results demonstrate that increased systemic acetate concentrations are functionally integrated by CD8(+) T cells and translate into increased glycolytic and functional capacity. The immune system thus directly relates systemic metabolism with immune alertness. PMID:27212436

  13. Bystander suppression of allergic airway inflammation by lung resident memory CD8+ T cells

    Marsland, Benjamin J.; Harris, Nicola L.; Camberis, Mali; Kopf, Manfred; Hook, Sarah M.; Le Gros, Graham


    CD8+ memory T cells have recently been recognized as playing a key role in natural immunity against unrelated viral infections, a phenomenon referred to as "heterologous antiviral immunity." We now provide data that the cellular immunological interactions that underlie such heterologous immunity can play an equally important role in regulating T helper 2 immune responses and protecting mucosal surfaces from allergen-induced inflammation. Our data show that CD8+ T cells, either retained in the lung after infection with influenza virus, or adoptively transferred via the intranasal route can suppress allergic airway inflammation. The suppression is mediated by IFN-, which acts to reduce the activation level, T helper 2 cytokine production, airways hyperresponsiveness, and migration of allergen-specific CD4+ T cells into the lung, whereas the systemic and draining lymph node responses remain unchanged. Of note, adoptive transfer of previously activated transgenic CD8+ T cells conferred protection against allergic airway inflammation, even in the absence of specific-antigen. Airway resident CD8+ T cells produced IFN- when directly exposed to conditioned media from activated dendritic cells or the proinflammatory cytokines IL-12 and IL-18. Taken together these data indicate that effector/memory CD8+ T cells present in the airways produce IFN- after inflammatory stimuli, independent of specific-antigen, and as a consequence play a key role in modifying the degree and frequency of allergic responses in the lung.

  14. Dynamic analysis of CD127 expression on memory CD8 T cells from patients with chronic hepatitis B during telbivudine treatment

    Lv Guocai


    Full Text Available Abstract Background Accumulating evidence supports the theory that expression of CD127 on CD8 T cells during the process of antiviral immune response indicates a subset of effect CD8 T cells that successfully develop into fully protective memory. CD8 T cells expression of CD127 may be used as a predictor to evaluate disease status in chronic viral infection. The aim of this study was to investigate the CD127 expression level on different subsets of CD8 T cell and explore the relationship between CD127 expression on CD8 memory T cells and serum hepatitis B virus (HBV DNA and hepatitis B e antigen (HBeAg levels in patients with chronic hepatitis B (CHB. We also aimed to investigate the CD127 expression pattern on CD8 memory T cells of CHB patients who were treated with Telbivudine. Methods/Results Twenty HBeAg-positive CHB patients were selected and treated with telbivudine 600 mg/day for 48 weeks. The memory CD8 T cells were characterized by expression of CD45RA and CD27 markers. CD127 expression on the CD8 T-cell surface was measured by four-colour flow cytometry. Our results showed that CD127 expression on memory CD8 T cells was reduced in CHB patients. There was a strong negative correlation between CD127 expression on memory CD8 T cells and serum HBV DNA and HBeAg levels in CHB patients. Moreover, successful antiviral therapy increased CD127 expression on CD8 memory T cells as well as on HBV-specific CD8 T cells in CHB patients. Conclusion These results suggest that diminished CD127 expression on CD8 memory T cells of CHB patients is a potential mechanism explaining cellular immune function impairment in CHB infection, and that CD127 expression on CD8 memory T cells is a useful indicator for evaluating the effects of anti-HBV therapy.

  15. Function, phenotype and development of human CD161+CD8 T cells

    Walker, Lucy Jane; Klenerman, Paul; Barnes, Eleanor


    Tc17 cells and the semi-invariant human mucosal associated invariant T (MAIT) cells are important CD8+ tissue-homing cell populations. Both are characterized by high expression of CD161 (++) and type-17 differentiation, yet their origins and relationships remain poorly defined. By transcriptional and functional analyses it is demonstrated that a pool of polyclonal, pre-committed type-17 CD161++CD8αβ+ T cells exists in cord blood, from which a prominent MAIT cell (TCR Vα7.2+/Vβ2 or 13.2) popul...

  16. CD8 T Cell Sensory Adaptation Dependent on TCR Avidity for Self-Antigens

    Marquez, M.-E.; Ellmeier, W.; Sanchez-Guajardo, Vanesa Maria; Freitas, A.A.; Acuto, O.; Di Bartolo, V.


    Adaptation of the T cell activation threshold may be one mechanism to control autoreactivity. To investigate its occurrence in vivo, we engineered a transgenic mouse model with increased TCR-dependent excitability by expressing a Zap70 gain-of-function mutant (ZAP-YEEI) in postselection CD8...... thymocytes and T cells. Increased basal phosphorylation of the Zap70 substrate linker for activation of T cells was detected in ZAP-YEEI-bearing CD8 T cells. However, these cells were not activated, but had reduced levels of TCR and CD5. Moreover, they produced lower cytokine amounts and showed faster......-YEEI suggested that signal tuning occurred during thymic maturation. Importantly, although P14 ﰌ ZAP-YEEI peripheral CD8 T cells were reduced in number and showed lower Ag-induced cytokine production and limited lymphopenia-driven proliferation, the peripheral survival/ expansion and Ag responsiveness of HY ﰌ...

  17. Inhibitory receptor expression depends more dominantly on differentiation and activation than exhaustion of human CD8 T cells

    Amandine eLegat


    Full Text Available Under conditions of chronic antigen stimulation, such as persistent viral infection and cancer, CD8 T cells may diminish effector function, which has been termed exhaustion. Expression of inhibitory Receptors (iRs is often regarded as a hallmark of exhaustion. Here we studied the expression of eight different iRs by CD8 T cells of healthy humans, including CTLA-4, PD1, TIM3, LAG3, 2B4, BTLA, CD160 and KLRG-1. We show that many iRs are expressed upon activation, and with progressive differentiation to effector cells, even in absence of long-term (chronic antigenic stimulation. In particular, we evaluated the direct relationship between iR expression and functionality in CD8 T cells by using anti-CD3 and anti-CD28 stimulation to stimulate all cells and differentiation subsets. We observed a striking upregulation of certain iRs following the cytokine production wave, in agreement with the notion that iRs function as a negative feedback mechanism. Intriguingly, we found no major impairment of cytokine production in cells positive for a broad array of iRs, as previously shown for PD1 in healthy donors. Rather, the expression of the various iRs strongly correlated with T cell differentiation or activation states, or both. Furthermore, we analyzed CD8 T cells from lymph nodes (LNs of melanoma patients. Interestingly, we found altered iR expression and lower cytokine production by T cells from metastatic LNs, but also from non-metastatic LNs, likely due to mechanisms which are not related to exhaustion. Together, our data shows that expression of iRs per se does not mark dysfunctional cells, but is rather tightly linked to activation and differentiation. This study highlights the importance of considering the status of activation and differentiation for the study and the clinical monitoring of CD8 T cells.

  18. Perforin and Fas in murine gammaherpesvirus-specific CD8(+) T cell control and morbidity

    Topham, D J; Cardin, R C; Christensen, Jan Pravsgaard;


    The immune system uses both virus-specific T cells and B cells to control the acute and latent phases of respiratory infection with the murine gammaherpesvirus 68 (gammaHV-68). We sought to further define the important effector mechanisms for CD8(+) T cells. First, depletion of the CD4(+) T cells...

  19. Recovery of CD8+ T-cell function during systemic chemotherapy in advanced ovarian cancer.

    Coleman, Sharon; Clayton, Aled; Mason, Malcolm D; Jasani, Bharat; Adams, Malcolm; Tabi, Zsuzsanna


    Immunologic approaches are emerging as new treatment options in several types of cancer. However, whereas the ability of patients to develop potent CD8+ T-cell responses is crucial for efficient antitumor responses, immunocompetence and T-cell function are not tested routinely in patients entering immunotherapy. The objective of our study was to monitor T-cell function in advanced cancer and during chemotherapy. CD8+ T-cell function of 21 patients with advanced ovarian cancer (stages III-IV) was assessed by cytokine flow cytometry following stimulation of 42 PBMC samples with a panel of synthetic viral peptides in vitro, consisting of pan-Caucasian epitopes. CD8+ T-cell responses were significantly lower in patients with high levels (>200 units/mL) of Ca125 (marker of tumor load and progression) than in those with low Ca125 levels (P = 0.0013). In longitudinal studies of nine patients, chemotherapy was associated with decreasing Ca125 levels in seven cases and also with improvement or maintenance of CD8+ T-cell function in seven cases. After the full course of chemotherapy, five of nine patients in remission displayed potent CD8+ T-cell responses, whereas four of nine patients in progression displayed low or decreasing T-cell responses, pointing toward a correlation between T-cell function and clinical response. Our results show for the first time that CD8+ T-cell function is not permanently suppressed in advanced cancer and successful chemotherapy is associated with improved antigen-specific T-cell reactivity. We suggest that functional assays determining T-cell immunocompetence can be valuable tools for optimizing cancer immunotherapy for improved clinical success. PMID:16061686

  20. Praziquantel Facilitates IFN-γ-Producing CD8+ T Cells (Tc1) and IL-17-Producing CD8+ T Cells (Tc17) Responses to DNA Vaccination in Mice

    Qiang Zou; Xin Yao; Jin Feng; Zhinan Yin; Richard Flavell; Yanxin Hu; Guoxing Zheng; Jin Jin; Youmin Kang; Bing Wu; Xiaoxuan Liang; Congcong Feng; Hu Liu; Weiyi Li; Xianzheng Wang


    BACKGROUND: CD8(+) cytotoxic T lymphocytes (CTLs) are crucial for eliminating hepatitis B virus (HBV) infected cells. DNA vaccination, a novel therapeutic strategy for chronic virus infection, has been shown to induce CTL responses. However, accumulated data have shown that CTLs could not be effectively induced by HBV DNA vaccination. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report that praziquantel (PZQ), an anti-schistoma drug, could act as an adjuvant to overcome the lack of potent CTL res...

  1. Regulation of maturation and activating potential in CD8+ versus CD8- dendritic cells following in vivo infection with vaccinia virus.

    Yammani, Rama D; Pejawar-Gaddy, Sharmila; Gurley, Thaddeus C; Weimer, Eric T; Hiltbold, Elizabeth M; Alexander-Miller, Martha A


    DC maturation is known to be a necessary step in the generation of an effective immune response. We have used vaccinia virus (VACV) as a model to investigate the regulation of DC subsets in vivo following infection. While a number of in vitro studies have shown that DC infected with VACV fail to undergo maturation, the effect of VACV infection on the maturation of and cytokine production by DC subsets in vivo remains less defined. We have found that following systemic infection with vaccinia virus, both CD8+ and CD8- dendritic cells are infected. The number of infected DC peaked at 6 h and was highly decreased by 24 h post-infection. In both subsets, there was evidence of generalized upregulation of costimulatory molecules. Surprisingly, this included vaccinia infected DC, suggesting the regulation of DC maturation in vivo is much more complex and likely influenced by DC extrinsic signals. However, while we observed generalized upregulation of costimulatory molecules, IL-12 production was restricted to a subset of non-infected cells in both the CD8+ and CD8- DC populations. Importantly, the control of IL-12 production was differentially dependent on MyD88 signaling. IL-12 production was ablated in the absence of MyD88 in CD8- DC, while it was unchanged in CD8+ DC. These findings provide new insights into the control of DC maturation in vivo and demonstrate that the regulation of maturation in vivo following virus infection can be differentially controlled in distinct types of DC. PMID:18586296

  2. Lung CD8+ T cells in COPD have increased expression of bacterial TLRs

    Freeman Christine M


    Full Text Available Abstract Background Toll-like receptors (TLRs on T cells can modulate their responses, however, the extent and significance of TLR expression by lung T cells, NK cells, or NKT cells in chronic obstructive pulmonary disease (COPD is unknown. Methods Lung tissue collected from clinically-indicated resections (n = 34 was used either: (a to compare the expression of TLR1, TLR2, TLR2/1, TLR3, TLR4, TLR5, TLR6 and TLR9 on lung CD8+ T cells, CD4+ T cells, NK cells and NKT cells from smokers with or without COPD; or (b to isolate CD8+ T cells for culture with anti-CD3ε without or with various TLR ligands. We measured protein expression of IFN-γ, TNF-α, IL-13, perforin, granzyme A, granzyme B, soluble FasL, CCL2, CCL3, CCL4, CCL5, CCL11, and CXCL9 in supernatants. Results All the lung subsets analyzed demonstrated low levels of specific TLR expression, but the percentage of CD8+ T cells expressing TLR1, TLR2, TLR4, TLR6 and TLR2/1 was significantly increased in COPD subjects relative to those without COPD. In contrast, from the same subjects, only TLR2/1 and TLR2 on lung CD4+ T cells and CD8+ NKT cells, respectively, showed a significant increase in COPD and there was no difference in TLR expression on lung CD56+ NK cells. Production of the Tc1 cytokines IFN-γ and TNF-α by lung CD8+ T cells were significantly increased via co-stimulation by Pam3CSK4, a specific TLR2/1 ligand, but not by other agonists. Furthermore, this increase in cytokine production was specific to lung CD8+ T cells from patients with COPD as compared to lung CD8+ T cells from smokers without COPD. Conclusions These data suggest that as lung function worsens in COPD, the auto-aggressive behavior of lung CD8+ T cells could increase in response to microbial TLR ligands, specifically ligands against TLR2/1.

  3. Exhaustion of Activated CD8 T Cells Predicts Disease Progression in Primary HIV-1 Infection.

    Hoffmann, Matthias; Pantazis, Nikos; Martin, Genevieve E; Hickling, Stephen; Hurst, Jacob; Meyerowitz, Jodi; Willberg, Christian B; Robinson, Nicola; Brown, Helen; Fisher, Martin; Kinloch, Sabine; Babiker, Abdel; Weber, Jonathan; Nwokolo, Nneka; Fox, Julie; Fidler, Sarah; Phillips, Rodney; Frater, John


    The rate at which HIV-1 infected individuals progress to AIDS is highly variable and impacted by T cell immunity. CD8 T cell inhibitory molecules are up-regulated in HIV-1 infection and associate with immune dysfunction. We evaluated participants (n = 122) recruited to the SPARTAC randomised clinical trial to determine whether CD8 T cell exhaustion markers PD-1, Lag-3 and Tim-3 were associated with immune activation and disease progression. Expression of PD-1, Tim-3, Lag-3 and CD38 on CD8 T cells from the closest pre-therapy time-point to seroconversion was measured by flow cytometry, and correlated with surrogate markers of HIV-1 disease (HIV-1 plasma viral load (pVL) and CD4 T cell count) and the trial endpoint (time to CD4 count approaches. PMID:27415828

  4. Cutting edge: neuronal recognition by CD8 T cells elicits central diabetes insipidus.

    Scheikl, Tanja; Pignolet, Béatrice; Dalard, Cécile; Desbois, Sabine; Raison, Danièle; Yamazaki, Masanori; Saoudi, Abdelhadi; Bauer, Jan; Lassmann, Hans; Hardin-Pouzet, Hélène; Liblau, Roland S


    An increasing number of neurologic diseases is associated with autoimmunity. The immune effectors contributing to the pathogenesis of such diseases are often unclear. To explore whether self-reactive CD8 T cells could attack CNS neurons in vivo, we generated a mouse model in which the influenza virus hemagglutinin (HA) is expressed specifically in CNS neurons. Transfer of cytotoxic anti-HA CD8 T cells induced an acute but reversible encephalomyelitis in HA-expressing recipient mice. Unexpectedly, diabetes insipidus developed in surviving animals. This robust phenotype was associated with preferential accumulation of cytotoxic CD8 T cells in the hypothalamus, upregulation of MHC class I molecules, and destruction of vasopressin-expressing neurons. IFN-γ production by the pathogenic CD8 T cells was necessary for MHC class I upregulation by hypothalamic neurons and their destruction. This novel mouse model, in combination with related human data, supports the concept that autoreactive CD8 T cells can trigger central diabetes insipidus. PMID:22504649

  5. Immunological control of a murine gammaherpesvirus independent of CD8+ T cells

    Stevenson, P G; Cardin, R D; Christensen, Jan Pravsgaard; Doherty, P C

    Adult thymectomized C57 BL/6J mice were depleted of T cell subsets by MAb treatment either prior to, or after, respiratory challenge with murine gammaherpesvirus-68. Protection against acute infection was maintained when either the CD4+ or the CD8+ T cell population was greatly diminished, whereas...... the concurrent removal of both T cell subsets proved invariably fatal. The same depletions had little effect on mice with established infection. The results indicate firstly that both CD4+ and CD8+ T cells play a significant part in dealing with the acute infection, and secondly that virus...

  6. Programmed death-1 expression on HIV-1-specific CD8+ T cells is shaped by epitope specificity, T-cell receptor clonotype usage and antigen load

    Kløverpris, Henrik N; McGregor, Reuben; McLaren, James E; Ladell, Kristin; Buus, Anette Stryhn; Koofhethile, Catherine; Brener, Jacqui; Chen, Fabian; Riddell, Lynn; Graziano, Luzzi; Klenerman, Paul; Leslie, Alasdair; Buus, Søren; Price, David A; Goulder, Philip


    ) clonotypes within individual HIV-1-specific CD8+ T-cell populations was also apparent, independent of clonal dominance hierarchies. Positive correlations were detected between PD-1 expression and plasma viral load, which were reinforced by stratification for epitope sequence stability and dictated by...... effector memory CD8+ T cells. CONCLUSION: Collectively, these data suggest that PD-1 expression on HIV-1-specific CD8+ T cells tracks antigen load at the level of epitope specificity and TCR clonotype usage. These findings are important because they provide evidence that PD-1 expression levels are......OBJECTIVES: Although CD8+ T cells play a critical role in the control of HIV-1 infection,their antiviral efficacy can be limited by antigenic variation and immune exhaustion.The latter phenomenon is characterized by the upregulation of multiple inhibitory receptors, such as programmed death-1 (PD-1...

  7. Prolonged activation of virus-specific CD8+T cells after acute B19 infection.


    Full Text Available BACKGROUND: Human parvovirus B19 (B19 is a ubiquitous and clinically significant pathogen, causing erythema infectiosum, arthropathy, transient aplastic crisis, and intrauterine fetal death. The phenotype of CD8+ T cells in acute B19 infection has not been studied previously. METHODS AND FINDINGS: The number and phenotype of B19-specific CD8+ T cell responses during and after acute adult infection was studied using HLA-peptide multimeric complexes. Surprisingly, these responses increased in magnitude over the first year post-infection despite resolution of clinical symptoms and control of viraemia, with T cell populations specific for individual epitopes comprising up to 4% of CD8+ T cells. B19-specific T cells developed and maintained an activated CD38+ phenotype, with strong expression of perforin and CD57 and downregulation of CD28 and CD27. These cells possessed strong effector function and intact proliferative capacity. Individuals tested many years after infection exhibited lower frequencies of B19-specific cytotoxic T lymphocytes, typically 0.05%-0.5% of CD8+ T cells, which were perforin, CD38, and CCR7 low. CONCLUSION: This is the first example to our knowledge of an "acute" human viral infection inducing a persistent activated CD8+ T cell response. The likely explanation--analogous to that for cytomegalovirus infection--is that this persistent response is due to low-level antigen exposure. CD8+ T cells may contribute to the long-term control of this significant pathogen and should be considered during vaccine development.

  8. Intrasinusoidal cytotoxic CD8+ T cells in nodular regenerative hyperplasia of the liver.

    Ziol, Marianne; Poirel, Helene; Kountchou, Gisele N; Boyer, Olivier; Mohand, Djamila; Mouthon, Luc; Tepper, Maryline; Guillet, Jean-Gerard; Guettier, Catherine; Raphael, Martine; Beaugrand, Michel


    Diffuse nodular regenerative hyperplasia (NRH) of the liver is an acquired architectural disturbance that can lead to portal hypertension. Although frequently associated with autoimmune or hematologic malignancies, its exact pathogenesis remains largely unknown. We observed CD8+ cytotoxic T cells in the liver sinusoids of 14 of 44 NRH patients and explored possible relationships between these lymphocytes and vascular damage. The immunophenotype of intrahepatic lymphocytes was determined using immunohistochemical analysis and endothelial injury using the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling method for apoptosis combined with endothelial cell labeling. Controls for the quantitative analysis of liver-infiltrating lymphocytes consisted of patients with chronic hepatitis C or normal liver (n = 13 and n = 6, respectively). Liver specimens from the 14 patients dislayed intrasinusoidal infiltrate composed of CD3+ and CD8+ lymphocytes, located near atrophic liver cell plates. Significantly more granzyme B+ and CD57+ lymphocytes were observed in NRH than chronic hepatitis C samples with quantitatively similar CD8+ infiltrates. Double-labeling revealed apoptotic endothelial sinusoidal cells in CD8+ T-cell-infiltrated areas in all NRH samples but never in chronic hepatitis C or normal livers. T-cell receptor rearrangement or immunoscope analysis suggested liver-specific polyclonal or oligoclonal T-cell expansions. Clinical and biological characteristics of the 14 patients were similar to those observed in the 30 patients with NRH devoid of lymphocytic infiltration. We report here that CD8+ cytotoxic T cells infiltrated the liver sinusoids of a high percentage (32%) of NRH patients and suggest that some NRH cases might result from chronic, cytotoxic CD8+ T-lymphocyte targeting of sinusoidal endothelial cells. PMID:15492992

  9. Activated iNKT cells promote memory CD8+ T cell differentiation during viral infection.

    Emma C Reilly

    Full Text Available α-Galactosylceramide (α-GalCer is the prototypical lipid ligand for invariant NKT cells. Recent studies have proposed that α-GalCer is an effective adjuvant in vaccination against a range of immune challenges, however its mechanism of action has not been completely elucidated. A variety of delivery methods have been examined including pulsing dendritic cells with α-GalCer to optimize the potential of α-GalCer. These methods are currently being used in a variety of clinical trials in patients with advanced cancer but cannot be used in the context of vaccine development against pathogens due to their complexity. Using a simple delivery method, we evaluated α-GalCer adjuvant properties, using the mouse model for cytomegalovirus (MCMV. We measured several key parameters of the immune response to MCMV, including inflammation, effector, and central memory CD8(+ T cell responses. We found that α-GalCer injection at the time of the infection decreases viral titers, alters the kinetics of the inflammatory response, and promotes both increased frequencies and numbers of virus-specific memory CD8(+ T cells. Overall, our data suggest that iNKT cell activation by α-GalCer promotes the development of long-term protective immunity through increased fitness of central memory CD8(+ T cells, as a consequence of reduced inflammation.

  10. TIL therapy broadens the tumor-reactive CD8(+) T cell compartment in melanoma patients

    Kvistborg, Pia; Shu, Chengyi Jenny; Heemskerk, Bianca; Fankhauser, Manuel; Thrue, Charlotte Albæk; Toebes, Mireille; van Rooij, Nienke; Linnemann, Carsten; van Buuren, Marit M; Urbanus, Jos H M; Beltman, Joost B; thor Straten, Per; Li, Yong F; Robbins, Paul F; Besser, Michal J; Schachter, Jacob; Kenter, Gemma G; Dudley, Mark E; Rosenberg, Steven A; Haanen, John B A G; Hadrup, Sine Reker; Schumacher, Ton N M


    -induced T cell reactivity against a panel of 145 melanoma-associated CD8(+) T cell epitopes. Using this approach, we demonstrate that individual tumor-infiltrating lymphocyte cell products from melanoma patients contain unique patterns of reactivity against shared melanoma-associated antigens, and that the...

  11. Features that shape CD8+ T-cell responses to viruses

    Correia de Almeida Fontaine Costa, A.I.


    CD8+ T cells, via their specific T-cell receptor (TCR), target infected cells when recognizing pathogen-derived peptides (epitopes) bound to class I major histocompatibility complex molecules (MHCI, or HLA-class I in humans). HLA-B is the most polymorphic of the classical HLA-I molecules. HLA-B-rest

  12. Secretion of interleukin-17 by CD8+ T cells expressing CD146 (MCAM).

    Dagur, Pradeep K; Biancotto, Angélique; Stansky, Elena; Sen, H Nida; Nussenblatt, Robert B; McCoy, J Philip


    Interleukin-17 (IL-17) has been associated with the pathogenesis of numerous autoimmune diseases. CD4+ T cells secreting IL-17 are termed Th17 cells. CD8+ T cells, designated Tc17 cells, are also capable of secreting IL-17. Here we describe a population of Tc17 cells characterized by the expression of surface CD146, an endothelial adhesion molecule. These cells display signatures of a human Tc17 genotype and phenotype. Circulating CD8+CD146+ T cells are present in low levels in healthy adults. Elevations in CD8+CD146+ T cells are found in Behcet's disease and birdshot retinochoroidopathy, which have been reported to have HLA class I associations. Sarcoidosis does not have a class I association and displays an increase in CD4+ CD146+ T cells but not in CD8+CD146+ T cells. CD146 on these cells may facilitate their ability to bind to, and migrate through, endothelium, as has been reported for CD4+CD146+ T cells. PMID:24681356

  13. miR-150 Regulates Differentiation and Cytolytic Effector Function in CD8+ T cells

    Smith, Norah L.; Wissink, Erin M.; Andrew Grimson; Rudd, Brian D.


    MicroRNAs regulate most mammalian genes, and they control numerous aspects of immune system development and function. Their precise roles in the CD8+ T cell response, however, remain unclear. In this report, we show that in the absence of the microRNA miR-150, CD8+ T cells fail to undergo robust expansion and differentiation into short-lived terminal effector cells in response to primary infection with Listeria monocytogenes or Vaccinia virus. Notably, even after transitioning into the memory...

  14. Efficacious early antiviral activity of HIV Gag- and Pol-specific HLA-B 2705-restricted CD8+ T cells

    Payne, Rebecca P; Kløverpris, Henrik; Sacha, Jonah B;


    The association between HLA-B 2705 and the immune control of human immunodeficiency virus type 1 (HIV-1) has previously been linked to the targeting of the HLA-B 2705-restricted Gag epitope KRWIILGLNK (KK10) by CD8(+) T cells. In order to better define the mechanisms of the HLA-B 2705 immune...... control of HIV, we first characterized the CD8(+) T-cell responses of nine highly active antiretroviral therapy (HAART)-naïve B 2705-positive subjects. Unexpectedly, we observed a strong response to an HLA-B 2705-restricted Pol epitope, KRKGGIGGY (KY9), in 8/9 subjects. The magnitude of the KY9 response...... respective CD8(+) T-cell response. By comparing inhibitions of viral replication by CD8(+) T cells specific for the Gag KK10, Pol KY9, and Vpr VL9 HLA-B 2705-restricted epitopes, we observed a consistent hierarchy of antiviral efficacy (Gag KK10 > Pol KY9 > Vpr VL9). This hierarchy was associated with early...

  15. Cloning analysis of HBV-specific CD8 T cell receptor gene in patients with acute hepatitis B

    Ning DING


    Full Text Available Objective To investigate the molecular mechanism of T cell receptor(TCR in CD8 T cell-mediated immune response to HBV in patients with acute hepatitis B(AHB.Methods Peripheral blood mononuclear cells(PBMCs were collected from HLA-A2-positive AHB patients.To determine HBsAg183-191 and HBsAg335-343-specific CD8 T cell frequencies,the PBMCs were stained by fluorescence-labeled anti-CD3,anti-CD8 and pentamers,and analyzed by flow cytometry.PBMCs from 6 patients were stimulated with epitopic peptide HBsAg335-343 in vitro for 3 to 4 weeks.HBV-specific CD8 T cells were isolated by magnetic activated cell sorting followed by flow florescence activated cell sorting.The mRNA of sorted cells was extracted after expanding by IL-2,anti-CD3 and anti-CD8.The full-length gene fragments of variable region of TCR α and β chains were gained by 5’-RACE,and then cloned and sequenced(≥50 clones for single chain of each sample.The gene families of TCR α and β chains were identified and the sequence characters of CDR3 were compared.Results Analysis of more than 600 cloned gene sequences of TCR α and β chains showed that the proliferated HBV-specific CD8 T cells from 6 AHB patients presented a predominant expression in TCR α and chains,with 2-4 α chain families and 1-4 chain families in each case.The α2,α14,α15,β3,β13 and 23 families were detected in more than one case.The chain genes were all 13 for all tested clones in one case.For the same α chain or-chain family,CDR3 sequences tended to be identical in one case but different among cases.Conclusions HBV-specific CD8 T cells with antigenic peptide-induced proliferation present predominance in the usage of TCR α and β chains.This property might be one of the important molecular factors influencing anti-HBV immunity.

  16. CD11b expression as a marker to distinguish between recently activated effector CD8(+) T cells and memory cells

    Christensen, Jeanette Erbo; Ørding Andreasen, Susanne; Christensen, Jan Pravsgaard;


    subset. Polyclonal virus-specific effector and memory CD8(+) T cells from lymphocytic choriomeningitis- and vesicular stomatitis virus-infected mice were visualized through staining for intracellular IFN-gamma or binding of MHC-peptide tetramers, and Mac-1 expression was evaluated. Naive T cells and most......CD8(+) T cells in different activation states have been difficult to identify phenotypically. In this study we have investigated whether Mac-1 (CD11b) expression can be used as a criterion to distinguish between recently activated effector cells and memory cells belonging to the CD8(+) T cell...... virus-specific memory CD8(+) T cells express little or no Mac-1 independent of the virus model employed. In contrast, the majority of CD8(+) T cells present during acute infection express a significant level of Mac-1 and, similarly, Mac-1 expression is found on secondary effectors generated in response...

  17. IL-6 trans-Signaling-Dependent Rapid Development of Cytotoxic CD8+ T Cell Function

    Jan P. Böttcher


    Full Text Available Immune control of infections with viruses or intracellular bacteria relies on cytotoxic CD8+ T cells that use granzyme B (GzmB for elimination of infected cells. During inflammation, mature antigen-presenting dendritic cells instruct naive T cells within lymphoid organs to develop into effector T cells. Here, we report a mechanistically distinct and more rapid process of effector T cell development occurring within 18 hr. Such rapid acquisition of effector T cell function occurred through cross-presenting liver sinusoidal endothelial cells (LSECs in the absence of innate immune stimulation and known costimulatory signaling. Rather, interleukin-6 (IL-6 trans-signaling was required and sufficient for rapid induction of GzmB expression in CD8+ T cells. Such LSEC-stimulated GzmB-expressing CD8+ T cells further responded to inflammatory cytokines, eliciting increased and protracted effector functions. Our findings identify a role for IL-6 trans-signaling in rapid generation of effector function in CD8+ T cells that may be beneficial for vaccination strategies.

  18. A secreted form of the human lymphocyte cell surface molecule CD8 arises from alternative splicing

    The human lymphocyte differentiation antigen CD8 is encoded by a single gene that gives rise to a 33- to 34-kDa glycoprotein expressed on the cell surface as a dimer and in higher molecular mass forms. The authors demonstrate that the mRNA is alternatively spliced so that an exon encoding a transmembrane domain is deleted. This gives rise to a 30-kDa molecule that is secreted and exists primarily as a monomer. mRNA corresponding to both forms is present in peripheral blood lymphocytes, Con A-activated peripheral blood lymphocytes, and three CD8+ T-cell lines, with the membrane form being the major species. However, differences in the ratio of mRNA for membrane CD8 and secreted CD8 exist. In addition, the splicing pattern observed differs from the pattern found for the mouse CD8 gene. This mRNA is also alternatively spliced, but an exon encoding a cytoplasmic region is deleted, giving rise to a cell surface molecule that differs in its cytoplasmic tail from the protein encoded by the longer mRNA. Neither protein is secreted. This is one of the first examples of a different splicing pattern between two homologous mouse and human genes giving rise to very different proteins. This represents one mechanism of generating diversity during speciation

  19. HIV-specific CD8~+ T cell responses to HXB2 Gag and Nef peptide pools in Chinese HIV/AIDS patients


    HXB2 is primarily used as a template strain in developing HIV vaccines in Europe and the US. However,it is not yet known whether the strain can induce strong HIV-specific CD8+ T cell responses in Chinese HIV/AIDS patients. In the present study,two groups of subjects were investigated:9 AIDS patients and 7 long-term nonprogressors (LTNPs). HIV-specific CD8+ T cell responses were examined in all patients through the ELISPOT assay. CD4+ T cell counts,CD8+ T cell counts,viral load and HIV subtype of each patient were also measured. Thailand B virus strain was identified among all the patients. The breadth and magnitude of HIV-specific CD8+ T cell responses in the LTNPs group are greater than those in the AIDS group (P<0.01). There is a positive correlation between magnitude of HIV-specific CD8+ T cell responses and CD4+ T cells,and a negative correlation between HIV-specific CD8+ T cell responses and mean viral load. In summary,the HIV-specific CD8+ T cell responses to the HXB2 Gag and Nef peptide pools are considerable in Chinese HIV/AIDS patients infected with Thailand B virus strain. HIV-1 vaccines based on HXB2 strain that can induce extensive immunity may be helpful for Chinese.

  20. Tumor-specific CD4+ T cells maintain effector and memory tumor-specific CD8+ T cells

    Church, Sarah E; Jensen, Shawn M; Antony, Paul A; Restifo, Nicholas P; Fox, Bernard A


    Immunotherapies that augment antitumor T cells have had recent success for treating patients with cancer. Here we examined whether tumor-specific CD4+ T cells enhance CD8+ T-cell adoptive immunotherapy in a lymphopenic environment. Our model employed physiological doses of tyrosinase-related protein 1-specific CD4+ transgenic T cells-CD4+ T cells and pmel-CD8+ T cells that when transferred individually were subtherapeutic; however, when transferred together provided significant (p ≤ 0.001) therapeutic efficacy. Therapeutic efficacy correlated with increased numbers of effector and memory CD8+ T cells with tumor-specific cytokine expression. When combined with CD4+ T cells, transfer of total (naïve and effector) or effector CD8+ T cells were highly effective, suggesting CD4+ T cells can help mediate therapeutic effects by maintaining function of activated CD8+ T cells. In addition, CD4+ T cells had a pronounced effect in the early posttransfer period, as their elimination within the first 3 days significantly (p < 0.001) reduced therapeutic efficacy. The CD8+ T cells recovered from mice treated with both CD8+ and CD4+ T cells had decreased expression of PD-1 and PD-1-blockade enhanced the therapeutic efficacy of pmel-CD8 alone, suggesting that CD4+ T cells help reduce CD8+ T-cell exhaustion. These data support combining immunotherapies that elicit both tumor-specific CD4+ and CD8+ T cells for treatment of patients with cancer. PMID:24114780

  1. miR-150 Regulates Differentiation and Cytolytic Effector Function in CD8+ T cells.

    Smith, Norah L; Wissink, Erin M; Grimson, Andrew; Rudd, Brian D


    MicroRNAs regulate most mammalian genes, and they control numerous aspects of immune system development and function. Their precise roles in the CD8+ T cell response, however, remain unclear. In this report, we show that in the absence of the microRNA miR-150, CD8+ T cells fail to undergo robust expansion and differentiation into short-lived terminal effector cells in response to primary infection with Listeria monocytogenes or Vaccinia virus. Notably, even after transitioning into the memory pool, miR-150(-/-) cells still mount a weaker recall response to secondary infection, and remain less differentiated than their wild-type counterparts. Transcriptome analysis shows miR-150 gene targets are globally upregulated in cells lacking miR-150, and amongst these targets, we found misregulation of genes associated with proliferation and effector cell function. These transcriptome data suggest that miR-150 deficient CD8+ T cells are less efficient in killing infected cells, which we validate experimentally. Together, these results reveal a cell-intrinsic role for miR-150 in the regulation of effector CD8+ T cell fate and function. PMID:26549197

  2. Differential requirement of CD28 costimulation for activation of murine CD8+ intestinal intraepithelial lymphocyte subsets and lymph node cells.

    Gelfanov, V; Lai, Y G; Gelfanova, V; Dong, J Y; Su, J P; Liao, N S


    The CD8+CD4- (CD8+) murine small intestinal intraepithelial lymphocytes (IELs) contain two subpopulations, one expressing alpha alpha-CD8 homodimers and another alpha beta-CD8 heterodimers. In this study, plate-bound anti-TCR beta-chain (TCR-beta) mAb alone or combined with anti-CD28 mAb is used as a model system to study activation requirement of these two CD8+ IEL subsets. In contrast to CD8+ lymph node (LN) cells that require both TCR and CD28 triggering for activation, alpha beta-CD8+ IELs proliferate and produce IL-2 and IFN-gamma when stimulated with anti-TCR-beta mAb alone, and soluble CTLA-4 Ig has no effect on their responses. On the other hand, alpha alpha-CD8+ IELs neither make IL-2 or IFN-gamma nor proliferate even when both stimuli are provided. However, alpha alpha-CD8+ IELs are capable of proliferation in both CD8+ IEL subsets is lower than in CD8+ LN cells, which contributes to the weaker and delayed response of CD8+ IELs. PMID:7602124

  3. Is an increase in CD4/CD8 T-cell ratio in lymph node fine needle aspiration helpful for diagnosing Hodgkin lymphoma? A study of 85 lymph node FNAs with increased CD4/CD8 ratio

    Hernandez Osvaldo


    Full Text Available Abstract Background An elevated CD4/CD8 T-cell ratio on flow cytometry (FCM analysis has been reported in the literature to be associated with Hodgkin lymphoma (HL. The purpose of our study was to determine the diagnostic significance of an elevated CD4/CD8 ratio in lymph node fine needle aspiration (FNA specimens. Design Between 1996 and 2002, out of 837 lymph node FNAs submitted for flow cytometry analysis, 85 cases showed an elevated CD4/CD8 ratio, defined as greater than or equal to 4, without definitive evidence of a lymphoproliferative disorder. The cytologic diagnoses of these 85 cases were grouped into four categories: reactive, atypical, Hodgkin lymphoma (HL, and non-Hodgkin lymphoma (NHL. Histologic follow-up was available in 17/85 (20% of the cases. Results 5 of the 64 cases in which FCM and cytology did not reveal evidence of a lymphoproliferative disease had tissue follow-up because of persistent lymphadenopathy and high clinical suspicion. 3/5 (60% confirmed the diagnosis of reactive lymphadenopathy. The two remaining cases (40% were positive for lymphoma (1HL, 1NHL. 8/15 cases called atypical on cytology had histologic follow-up. 7/8 (87.5% cases were positive for lymphoma (3HL, 4NHL. 3/4 cases called HL on cytology had tissue follow-up and all 3 (100% confirmed the diagnosis of HL. One case diagnosed as NHL on cytology was found to be a diffuse large B-cell lymphoma. In summary, out of 17 cases with histologic follow-up 4/17 (24% were reactive with CD4/CD8 T-cell ratio of 4.1–29, 7/17 (41% were HLs with CD4/CD8 T-cell ratio of 5.3 – 11, and 6/17 (35% were NHLs with CD4/CD8 T-cell ratio of 4.2 – 14. Conclusion An elevated CD4/CD8 ratio on FCM is a nonspecific finding which may be seen in both reactive and lymphoproliferative disorders. The cytomorphologic features of the smear are more relevant than the sole flow cytometric finding of an elevated CD4/CD8 ratio.

  4. Prolonged activation of virus-specific CD8+T cells after acute B19 infection

    Isa, Adiba; Kasprowicz, Victoria; Norbeck, Oscar;


    : The number and phenotype of B19-specific CD8+ T cell responses during and after acute adult infection was studied using HLA-peptide multimeric complexes. Surprisingly, these responses increased in magnitude over the first year post-infection despite resolution of clinical symptoms and control of...... and intact proliferative capacity. Individuals tested many years after infection exhibited lower frequencies of B19-specific cytotoxic T lymphocytes, typically 0.05%-0.5% of CD8+ T cells, which were perforin, CD38, and CCR7 low. CONCLUSION: This is the first example to our knowledge of an "acute...

  5. Requirements for Peptide-induced T Cell Receptor Downregulation on Naive CD8+ T Cells

    Cai, Zeling; Kishimoto, Hidehiro; Brunmark, Anders; Jackson, Michael R.; Peterson, Per A.; Sprent, Jonathan


    The requirements for inducing downregulation of α/β T cell receptor (TCR) molecules on naive major histocompatibility complex class I–restricted T cells was investigated with 2C TCR transgenic mice and defined peptides as antigen. Confirming previous results, activation of 2C T cells in response to specific peptides required CD8 expression on the responder cells and was heavily dependent upon costimulation provided by either B7-1 or ICAM-1 on antigen-presenting cells (APC). These stringent re...

  6. Human purified CD8+ T cells: Ex vivo expansion model to generate a maximum yield of functional cytotoxic cells.

    Al-Shanti, Nasser; Aldahoudi, Ziyad


    CD8+ T cells are a critical component of the cellular immune response. They play an important role in the control of viral infection and eliminating cells with malignant potential. However, attempts to generate and expand human CD8+ T cells in vitro for an adoptive immunotherapy have been conducted with limitation of the very low frequency of CD8+ T cells in blood. Therefore, several expansion protocols have been developed to obtain large and efficient numbers of human CD8+ T cells for use in adoptive immunotherapies. In this study various common culture conditions using different cytokines IL-2, IL-4, IL-7, IL-10, IL-12 and IL-15 and autologous feeders and sera were investigated to expand human purified CD8+ T cells. The importance and the influence of these factors on the growth and phenotype of CD8+ T cell were assessed by serially sampling cultures using flow cytometry. We demonstrated that combination of IL-2 (50 U/ml) and autologous feeders induced maximal CD8+ T cell proliferation (40-50 folds) compared to other cytokines. Immunophenotypic analysis of cultured cells showed that expanded CD8+ T cells were activated and differentiated. Furthermore our expansion model also demonstrated that expanded CD8+ T cells are functionally cytotoxic active by killing Allogeneic LCLs cells. In conclusion, we have developed a reliable, simple method that uses minimal cell numbers to generate a high yield of functional cytotoxic CD8+ T cells, which can be used for the development of cellular immunotherapies. PMID:17190652

  7. Polymyalgia rheumatica is characterized by pro-inflammatory, senescent CD8+ T cells

    Van Der Geest, K.; Abdulahad, W.; Huitema, M.; Kroesen, B.; Rutgers, A.; Brouwer, E.; Boots, A.


    Background Polymyalgia rheumatica (PMR) is a frequent, inflammatory rheumatic disease affecting elderly people. Previous studies suggest that T cell mediated immune responses contribute to PMR. However, little is known about CD4+ and CD8+ T cell subsets and their function in PMR. Furthermore, it rem

  8. Effector CD4 and CD8 T Cells and Their Role in the Tumor Microenvironment

    Hadrup, Sine; Donia, Marco; thor Straten, Per


    with colo-rectal cancer (CRC), and also for others solid cancers. These data goes hand in hand with studies of clonality of TIL showing the T cells among TIL are expanded clonally, and also that tumor specific T cells of CD4 as well as CD8 type are enriched at the tumor site. The tumor microenvironment...

  9. Characterization of virus-primed CD8+ T cells with a type 1 cytokine profile

    Christensen, Jan Pravsgaard; Stenvang, J P; Marker, O; Thomsen, Allan Randrup


    killing. An enhanced cytotoxic potential as well as an increased capacity to produce IFN-gamma is observed for at least 2 months after infection and cell sorting analysis revealed that this could be ascribed to a long-standing increase in the frequency of CD8+ Pgp-1hi cells. Therefore, these results...

  10. Phenotyping of circulating CD8(+) T cell subsets in human cutaneous leishmaniasis

    Khamesipour, A.; Rostami, M.N.; Tasbihi, M.; Mohammadi, A.M.; Shahrestani, T.; Sarrafnejad, A.; Sohrabi, Yahya; Eskandari, S.E.; Valian, H.K.


    Roč. 14, č. 9 (2012), s. 702-711. ISSN 1286-4579 Institutional research plan: CEZ:AV0Z50520514 Institutional support: RVO:68378050 Keywords : CD8(+) T cells * memory T cells * cutaneous leishmaniasis * IFN-gamma Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.920, year: 2012

  11. Strong CD8+ T-cell responses against tumor-associated antigens prolong the recurrence-free interval after tumor treatment in patients with hepatocellular carcinoma

    We investigated whether tumor-specific CD8+T-cell responses affect tumor-free survival as well as the relationship between CD8+T-cell responses against tumor-associated antigens (TAAs) and the clinical course after tumor treatment in patients with hepatocellular carcinoma (HCC). Twenty patients with HCC that were treated by radiofrequency ablation or trans-catheter chemo-embolization (TACE) and in whom HCC was undetectable by ultrasonography, CT, and/or MRI 1 month after treatment were enrolled in the study. Before and after treatment for HCC, analyses of TAA (glypican-3, NY-ESO-1, and MAGE-1)-specific CD8+T-cell responses were evaluated with an interferon-γ enzyme-linked immunospot (ELISpot) assay using peripheral CD8+T-cells, monocytes, and 104 types of 20-mer synthetic peptide overlapping by 10 residues and spanning the entirety of the 3 TAAs. Sixteen out of 20 patients (80%) showed a positive response (≥10 TAA-specific cells/105 CD8+T-cells) before or after treatment. When we performed univariate analysis of prognostic factors for the tumor-free period in the 20 patients, platelet count, prothrombin time, and the number of TAA-specific CD8+T-cells after treatment were significant factors (P=0.027, 0.030, and 0.004, respectively). In multivariate analysis, the magnitude of the TAA-specific CD8+T-cell response (≥40 TAA-specific cells/105 CD8+T-cells) was the only significant prognostic factor for a prolonged tumor-free interval (hazard ratio 0.342, P=0.022). Our results suggest that strong TAA-specific CD8+T-cell responses suppress the recurrence of HCC. Immunotherapy to induce TAA-specific cytotoxic T lymphocytes by means such as the use of peptide vaccines should be considered for clinical application in patients with HCC after local therapy. (author)

  12. Interferon-alpha administration enhances CD8+ T cell activation in HIV infection.

    Maura Manion

    Full Text Available BACKGROUND: Type I interferons play important roles in innate immune defense. In HIV infection, type I interferons may delay disease progression by inhibiting viral replication while at the same time accelerating disease progression by contributing to chronic immune activation. METHODS: To investigate the effects of type I interferons in HIV-infection, we obtained cryopreserved peripheral blood mononuclear cell samples from 10 subjects who participated in AIDS Clinical Trials Group Study 5192, a trial investigating the activity of systemic administration of IFNα for twelve weeks to patients with untreated HIV infection. Using flow cytometry, we examined changes in cell cycle status and expression of activation antigens by circulating T cells and their maturation subsets before, during and after IFNα treatment. RESULTS: The proportion of CD38+HLA-DR+CD8+ T cells increased from a mean of 11.7% at baseline to 24.1% after twelve weeks of interferon treatment (p = 0.006. These frequencies dropped to an average of 20.1% six weeks after the end of treatment. In contrast to CD8+ T cells, the frequencies of activated CD4+ T cells did not change with administration of type I interferon (mean percentage of CD38+DR+ cells = 2.62% at baseline and 2.17% after 12 weeks of interferon therapy. As plasma HIV levels fell with interferon therapy, this was correlated with a "paradoxical" increase in CD8+ T cell activation (p<0.001. CONCLUSION: Administration of type I interferon increased expression of the activation markers CD38 and HLA DR on CD8+ T cells but not on CD4+ T cells of HIV+ persons. These observations suggest that type I interferons may contribute to the high levels of CD8+ T cell activation that occur during HIV infection.

  13. Cutting edge: membrane lymphotoxin regulates CD8(+) T cell-mediated intestinal allograft rejection.

    Guo, Z; Wang, J; Meng, L; Wu, Q; Kim, O; Hart, J; He, G; Zhou, P; Thistlethwaite, J R; Alegre, M L; Fu, Y X; Newell, K A


    Blocking the CD28/B7 and/or CD154/CD40 costimulatory pathways promotes long-term allograft survival in many transplant models where CD4(+) T cells are necessary for rejection. When CD8(+) T cells are sufficient to mediate rejection, these approaches fail, resulting in costimulation blockade-resistant rejection. To address this problem we examined the role of lymphotoxin-related molecules in CD8(+) T cell-mediated rejection of murine intestinal allografts. Targeting membrane lymphotoxin by means of a fusion protein, mAb, or genetic mutation inhibited rejection of intestinal allografts by CD8(+) T cells. This effect was associated with decreased monokine induced by IFN-gamma (Mig) and secondary lymphoid chemokine (SLC) gene expression within allografts and spleens respectively. Blocking membrane lymphotoxin did not inhibit rejection mediated by CD4(+) T cells. Combining disruption of membrane lymphotoxin and treatment with CTLA4-Ig inhibited rejection in wild-type mice. These data demonstrate that membrane lymphotoxin is an important regulatory molecule for CD8(+) T cells mediating rejection and suggest a strategy to avoid costimulation blockade-resistant rejection. PMID:11673481

  14. B cells pulsed with Helicobacter pylori antigen efficiently activate memory CD8+ T cells from H. pylori-infected individuals.

    Azem, Josef; Svennerholm, Ann-Mari; Lundin, B Samuel


    Helicobacter pylori infection causes chronic gastritis that may progress to peptic ulcers or gastric adenocarcinoma and thereby cause major world-wide health problems. Previous studies have shown that CD4+ T cells are important in the immune response to H. pylori in humans, but the role of CD8+ T cells is less clear. In order to study the CD8+ T cell response to H. pylori in greater detail, we have evaluated efficient conditions for activation of CD8+ T cells in vitro. We show that H. pylori-reactive CD8+ T cells can be activated most efficiently by B cells or dendritic cells pulsed with H. pylori antigens. We further show that the majority of CD8+ T cells in H. pylori-infected gastric mucosa are memory cells, and that memory CD8+ T cells sorted from peripheral blood of H. pylori-infected individuals respond 15-fold more to H. pylori urease compared to memory cells from uninfected subjects. We conclude that CD8+ T cells do participate in the immune response to H. pylori, and this may have implications for the development of more severe disease outcomes in H. pylori-infected subjects. PMID:16324887

  15. Association of Hepatitis C Virus Infection With CD4/CD8 Ratio in HIV-Positive Women

    O'Brien, Thomas R.; Prokunina-Olsson, Ludmila; Augenbraun, Michael; Plankey, Michael; Karim, Roksana; Sarkar, Monika; French, Audrey L.; Pierce, Chris; Strickler, Howard D.; Anastos, Kathryn


    Background: Recent studies reported that the CD4/CD8 T-cell ratio is inversely associated with biomarkers traditionally used to measure immune activation and systemic inflammation in highly active antiretroviral therapy–treated HIV-infected (HIV+) patients. The relation of hepatitis C virus (HCV) coinfection with the CD4/CD8 ratio in HIV+ patients is unknown. Methods: We examined 50,201 CD4/CD8 ratios measured over 20 years in 3 groups of HIV+ women enrolled in the Women's Interagency HIV Study: HCV antibody negative (n = 1734), cleared HCV (n = 231), and chronic HCV (n = 751) in multivariate models. IFNL4-ΔG genotype and HCV viral load were also considered. Results: Compared with HCV antibody negative status, chronic HCV infection was associated with lower CD4/CD8 ratios when HIV viral load was suppressed to the lower limit of quantification (β = −0.08; P = 0.002). Cleared HCV (β = −0.10; P = 0.0009), but not IFNL4-ΔG genotype or HCV viral load, was also associated with lower CD4/CD8 ratios when HIV viral load was suppressed to the lower limit of quantification. Conclusions: The association of HCV coinfection with CD4/CD8 ratio is consistent with previously observed associations of HCV coinfection with biomarkers traditionally used to measure immune activation and systemic inflammation in HIV+ patients. These data provide additional support for the use of CD4/CD8 ratio for routine monitoring of immune activation and inflammation in HIV+ patients, including those with HIV/HCV coinfection; however, the unexpected association between cleared HCV and lower CD4/CD8 ratio requires additional study. PMID:27183178

  16. Radiosensitivity of CD4 and CD8 positive human T lymphocytes by an in vitro colony formation assay

    The recent development of an in vitro lymphocyte colony assay provides a new opportunity to examine possible variations in human radiosensitivity using peripheral blood lymphocytes (PBL) in place of the hitherto used skin fibroblast assay. Our recent study showed that most of the colonies consisted of lymphocytes bearing CD4 or CD8 antigens. Since the fraction of CD4+ and CD8+ cells in PBL differs among individuals, it was suspected that individual radiosensitivity might be biased by the different subset frequencies if the dose-survival curves of the CD4+ and CD8+ cells differed. In the present study, CD4+ lymphocytes (helper/inducer T cells) and CD8+ lymphocytes (suppressor/cytotoxic T cells) were isolated from PBL and their dose-survival curves were determined. The results showed that the D10 (the dose required to reduce the surviving fraction to 10 %) was quite similar for these two types of cells (3.13 ± 0.10 Gy [mean ±SD] for CD4+, 3.34 ± 0.50 Gy for CD8+ and 3.07 ± 0.05 Gy for the unsorted cells), supporting the use of a whole PBL population for screening of individuals with altered radiosensitivity. (author)

  17. The effect of vitamin A on CD4+ and CD8+ cells irradiated by 60Co γ-ray

    The monocyte-depleted peripheral blood mononuclear cells were separated into CD4+ and CD8+ subpopulations by panning technique with McAb CD4 and CD8. The purity of CD4+ and CD8+ cells was 89.2% and 85.8% respectively, which was estimated by an indirect immunofluorescence technique. The radiosensitivities of CD4+ and CD8+ cells and the effect of DNA synthesis in both cells' subpopulations influenced by Vit A were assessed by 3H-TdR incorporation. The experimental result showed that after γ-radiation in different doses on CD4+ and CD8+ cells, the 3H-TdR incorporation was significantly decreased. The 3H-TdR incorporation rate in CD8+ cells irradiated with addition of 5 μg/ml Vit A increased significantly (p<0.05)

  18. Influence of race on microsatellite instability and CD8+ T cell infiltration in colon cancer.

    John M Carethers

    Full Text Available African American patients with colorectal cancer show higher mortality than their Caucasian counterparts. Biology might play a partial role, and prior studies suggest a higher prevalence for microsatellite instability (MSI among cancers from African Americans, albeit patients with MSI cancers have improved survival over patients with non-MSI cancers, counter to the outcome observed for African American patients. CD8+ T cell infiltration of colon cancer is postively correlated with MSI tumors, and is also related to improved outcome. Here, we utilized a 503-person, population-based colon cancer cohort comprising 45% African Americans to determine, under blinded conditions from all epidemiological data, the prevalence of MSI and associated CD8+ T cell infiltration within the cancers. Among Caucasian cancers, 14% were MSI, whereas African American cancers demonstrated 7% MSI (P = 0.009. Clinically, MSI cancers between races were similar; among microsatellite stable cancers, African American patients were younger, female, and with proximal cancers. CD8+ T cells were higher in MSI cancers (88.0 vs 30.4/hpf, P<0.0001, but was not different between races. Utilizing this population-based cohort, African American cancers show half the MSI prevalence of Caucasians without change in CD8+ T cell infiltration which may contribute towards their higher mortality from colon cancer.

  19. Human brain endothelial cells endeavor to immunoregulate CD8 T cells via PD-1 ligand expression in multiple sclerosis

    Pittet Camille L


    Full Text Available Abstract Background Multiple sclerosis (MS, an inflammatory disease of the central nervous system (CNS, is characterized by blood-brain barrier (BBB disruption and massive infiltration of activated immune cells. Engagement of programmed cell death-1 (PD-1 expressed on activated T cells with its ligands (PD-L1 and PD-L2 suppresses T cell responses. We recently demonstrated in MS lesions elevated PD-L1 expression by glial cells and absence of PD-1 on many infiltrating CD8 T cells. We have now investigated whether human brain endothelial cells (HBECs, which maintain the BBB, can express PD-L1 or PD-L2 and thereby modulate T cells. Methods We used primary cultures of HBECs isolated from non-tumoral CNS tissue either under basal or inflamed conditions. We assessed the expression of PD-L1 and PD-L2 using qPCR and flow cytometry. Human CD8 T cells were isolated from peripheral blood of healthy donors and co-cultured with HBECs. Following co-culture with HBECs, proliferation and cytokine production by human CD8 T cells were measured by flow cytometry whereas transmigration was determined using a well established in vitro model of the BBB. The functional impact of PD-L1 and PD-L2 provided by HBECs was determined using blocking antibodies. We performed immunohistochemistry for the detection of PD-L1 or PD-L2 concurrently with caveolin-1 (a cell specific marker for endothelial cells on post-mortem human brain tissues obtained from MS patients and normal controls. Results Under basal culture conditions, PD-L2 is expressed on HBECs, whilst PD-L1 is not detected. Both ligands are up-regulated under inflammatory conditions. Blocking PD-L1 and PD-L2 leads to increased transmigration and enhanced responses by human CD8 T cells in co-culture assays. Similarly, PD-L1 and PD-L2 blockade significantly increases CD4 T cell transmigration. Brain endothelium in normal tissues and MS lesions does not express detectable PD-L1; in contrast, all blood vessels in normal

  20. Change of paradigm: CD8+ T cells as important helper for CD4+ T cells during asthma and autoimmune encephalomyelitis

    Huber, Magdalena; Lohoff, Michael


    Summary The activation of naive CD4+ and CD8+ T cells in response to antigen and their subsequent proliferation and differentiation into effectors are important features of a cell-mediated immune response. CD4+ T cells (also known as T helper cells, Th) differentiate into several subpopulations including Th1, Th2, Th9, Th17, Tfh and Treg cells, characterized by specific cytokine profiles and effector functions. However, recent evidence indicates that CD8+ T cells (termed cytotoxic T lymphocyt...

  1. A subset of human plasmacytoid dendritic cells expresses CD8α upon exposure to herpes simplex virus type 1.

    Schuster, Philipp; Thomann, Sabrina; Werner, Maren; Vollmer, Jörg; Schmidt, Barbara


    Classical and plasmacytoid dendritic cells (DC) play important roles in the defense against murine and human infections with herpes simplex virus (HSV). So far, CD8α expression has only been reported for murine DC. CD8α(+) DC have prominent cross-presenting activities, which are enhanced by murine CD8α(+) PDC. The human orthologue of murine CD8α(+) DC, the CD141 (BDCA3)(+) DC, mainly cross-present after TLR3 ligation. We report here the serendipitous finding that a subset of human PDC upregulates CD8α upon HSV-1 stimulation, as shown by gene array and flow cytometry analyses. CD8α, not CD8ß, was expressed upon exposure. Markers of activation, migration, and costimulation were upregulated on CD8α-expressing human PDC. In these cells, increased cytokine and chemokine levels were detected that enhance development and function of T, B, and NK cells, and recruit immature DC, monocytes, and Th1 cells, respectively. Altogether, human CD8α(+) PDC exhibit a highly activated phenotype and appear to recruit other immune cells to the site of inflammation. Further studies will show whether CD8α-expressing PDC contribute to antigen cross-presentation, which may be important for immune defenses against HSV infections in vitro and in vivo. PMID:26082771

  2. A distinct subset of self-renewing human memory CD8+ T cells survives cytotoxic chemotherapy

    Turtle, Cameron J.; Swanson, Hillary M.; Fujii, Nobuharu; Estey, Elihu H.; Riddell, Stanley R.


    The mechanisms that maintain human T cell memory during normal and perturbed homeostasis are not fully understood. The repeated induction of profound lymphocytopenia in patients undergoing multiple cycles of cytotoxic chemotherapy infrequently results in severe infections with viruses controlled by memory T cells, suggesting that some memory T cells survive chemotherapy and restore immunity. Here we identify a distinct subpopulation of memory CD8+ T cells with the ability to rapidly efflux an...

  3. Pharmacologic Induction of CD8+ T Cell Memory: Better Living Through Chemistry

    Gattinoni, Luca; Klebanoff, Christopher A.; Restifo, Nicholas P


    The generation of a robust population of memory T cells is critical for effective vaccine and cell-based therapies to prevent and treat infectious diseases and cancer. A series of recent papers have established a new, cell-intrinsic approach in which small molecules target key metabolic and developmental pathways to enhance the formation and maintenance of highly functional CD8+ memory T cells. These findings raise the exciting new possibility of using small molecules, many of which are alrea...

  4. Bacteria modulate the CD8+ T cell epitope repertoire of host cytosol-exposed proteins to manipulate the host immune response.

    Yaakov Maman


    Full Text Available The main adaptive immune response to bacteria is mediated by B cells and CD4+ T-cells. However, some bacterial proteins reach the cytosol of host cells and are exposed to the host CD8+ T-cells response. Both gram-negative and gram-positive bacteria can translocate proteins to the cytosol through type III and IV secretion and ESX-1 systems, respectively. The translocated proteins are often essential for the bacterium survival. Once injected, these proteins can be degraded and presented on MHC-I molecules to CD8+ T-cells. The CD8+ T-cells, in turn, can induce cell death and destroy the bacteria's habitat. In viruses, escape mutations arise to avoid this detection. The accumulation of escape mutations in bacteria has never been systematically studied. We show for the first time that such mutations are systematically present in most bacteria tested. We combine multiple bioinformatic algorithms to compute CD8+ T-cell epitope libraries of bacteria with secretion systems that translocate proteins to the host cytosol. In all bacteria tested, proteins not translocated to the cytosol show no escape mutations in their CD8+ T-cell epitopes. However, proteins translocated to the cytosol show clear escape mutations and have low epitope densities for most tested HLA alleles. The low epitope densities suggest that bacteria, like viruses, are evolutionarily selected to ensure their survival in the presence of CD8+ T-cells. In contrast with most other translocated proteins examined, Pseudomonas aeruginosa's ExoU, which ultimately induces host cell death, was found to have high epitope density. This finding suggests a novel mechanism for the manipulation of CD8+ T-cells by pathogens. The ExoU effector may have evolved to maintain high epitope density enabling it to efficiently induce CD8+ T-cell mediated cell death. These results were tested using multiple epitope prediction algorithms, and were found to be consistent for most proteins tested.

  5. A dominant role for the immunoproteasome in CD8+ T cell responses to murine cytomegalovirus.

    Sarah Hutchinson

    Full Text Available Murine cytomegalovirus (MCMV is an important animal model of human cytomegalovirus (HCMV, a β-Herpesvirus that infects the majority of the world's population and causes disease in neonates and immunocompromised adults. CD8(+ T cells are a major part of the immune response to MCMV and HCMV. Processing of peptides for presentation to CD8(+ T cells may be critically dependent on the immunoproteasome, expression of which is affected by MCMV. However, the overall importance of the immunoproteasome in the generation of immunodominant peptides from MCMV is not known. We therefore examined the role of the immunoproteasome in stimulation of CD8(+ T cell responses to MCMV - both conventional memory responses and those undergoing long-term expansion or "inflation". We infected LMP7(-/- and C57BL/6 mice with MCMV or with newly-generated recombinant vaccinia viruses (rVVs encoding the immunodominant MCMV protein M45 in either full-length or epitope-only minigene form. We analysed CD8(+ T cell responses using intracellular cytokine stain (ICS and MHC Class I tetramer staining for a panel of MCMV-derived epitopes. We showed a critical role for immunoproteasome in MCMV affecting all epitopes studied. Interestingly we found that memory "inflating" epitopes demonstrate reduced immunoproteasome dependence compared to non-inflating epitopes. M45-specific responses induced by rVVs remain immunoproteasome-dependent. These results help to define a critical restriction point for CD8(+ T cell epitopes in natural cytomegalovirus (CMV infection and potentially in vaccine strategies against this and other viruses.

  6. A Critical Role of IL-21-Induced BATF in Sustaining CD8-T-Cell-Mediated Chronic Viral Control

    Gang Xin


    Full Text Available Control of chronic viral infections by CD8cells is critically dependent on CD4 help. In particular, helper-derived IL-21 plays a key role in sustaining the CD8cell response; however, the molecular pathways by which IL-21 sustains CD8cell immunity remain unclear. We demonstrate that IL-21 causes a phenotypic switch of transcription factor expression in CD8cells during chronic viral infection characterized by sustained BATF expression. Importantly, BATF expression during chronic infection is both required for optimal CD8cell persistence and anti-viral effector function and sufficient to rescue “unhelped” CD8cells. Mechanistically, BATF sustains the response by cooperating with IRF4, an antigen-induced transcription factor that is also critically required for CD8cell maintenance, to preserve Blimp-1 expression and thereby sustain CD8cell effector function. Collectively, these data suggest that CD4 T cells “help” the CD8 response during chronic infection via IL-21-induced BATF expression.

  7. CXCR3 expression defines a novel subset of innate CD8+ T cells that enhance immunity against bacterial infection and cancer upon stimulation with IL-15.

    Oghumu, Steve; Terrazas, Cesar A; Varikuti, Sanjay; Kimble, Jennifer; Vadia, Stephen; Yu, Lianbo; Seveau, Stephanie; Satoskar, Abhay R


    Innate CD8(+) T cells are a heterogeneous population with developmental pathways distinct from conventional CD8(+) T cells. However, their biology, classification, and functions remain incompletely understood. We recently demonstrated the existence of a novel population of chemokine (C-X-C motif) receptor 3 (CXCR3)-positive innate CD8(+) T cells. Here, we investigated the functional properties of this subset and identified effector molecules and pathways which mediate their function. Adoptive transfer of IL-15 activated CXCR3(+) innate CD8(+) T cells conferred increased protection against Listeria monocytogenes infection in susceptible IFN-γ(-/-) mice compared with similarly activated CXCR3(-) subset. This was associated with enhanced proliferation and IFN-γ production in CXCR3(+) cells. Further, CXCR3(+) innate cells showed enhanced cytotoxicity against a tumor cell line in vitro. In depth analysis of the CXCR3(+) subset showed increased gene expression of Ccl5, Klrc1, CtsW, GP49a, IL-2Rβ, Atp5e, and Ly6c but reduced IFN-γR2 and Art2b. Ingenuity pathway analysis revealed an up-regulation of genes associated with T-cell activation, proliferation, cytotoxicity, and translational initiation in CXCR3(+) populations. Our results demonstrate that CXCR3 expression in innate CD8(+) T cells defines a subset with enhanced cytotoxic potential and protective antibacterial immune functions. Immunotherapeutic approaches against infectious disease and cancer could utilize CXCR3(+) innate CD8(+) T-cell populations as novel clinical intervention strategies. PMID:25466888

  8. HIV感染者调节性T细胞消耗可导致HIV特异CD8+细胞凋亡%Treg Cells Depletion Can Lead to HIV-specific CD8 + Cells Apoptosis in HIV Patients

    焦艳梅; 福军亮; 张政; 计云霞; 王蕊; 张彤; 陈德喜; 吴昊


    Objective To investigate whether the decrease of CD4 + CD25 + FoxP3 + cells (Treg) can lead to HIV-specific CD8 +cells apoptosis in HIV patients. Methods We characterized Tregs among 75 antiviral-na(i)ve HIV-I-infected individuals in this study.Treg and CD8 + cell activation and apoptosis were detected and its relevance was analyzed; Treg cells and CD8 + cells were simultaneously purified and then co-cultured in vitro, and HIV-specific CD8 + cell apoptosis was detected with pentamer and annexin V. Results Absolute counts of circulating Treg was inversely correlated with up-regulated activation and apoptosis of CD8 + T cells. In addition, Tregs were found to suppress HIV peptite-induced apoptosis of HIV-specific CD8 + T cells. Conclusion These findings indicate that the decrease in Tregs closely correlate with increased apoptosis of CD8 + T cells, especially with HIV specific CD8 + T cells.%目的 了解在HIV感染患者CD4+CD25+FoxP3+调节性T细胞(Treg)的降低是否能够引起HIV特异CD8+细胞过度凋亡.方法 本研究对75例没有治疗的HIV患者进行研究,检测其外周血中Treg细胞计数及CD8+细胞的活化及凋亡情况并分析其相关性;同时纯化Treg细胞及CD8+细胞,在体外进行共培养,用五聚体检测HIV特异CD8+细胞的活化情况.结果 在HIV感染患者,Treg细胞与CD8+细胞的活化及凋亡呈负相关,Treg细胞能够抑制HIV特异的CD8+细胞的凋亡.结论 HIV感染患者Treg细胞的降低可导致CD8+细胞、尤其HIV特异CD8+细胞的凋亡增加.

  9. Role of CD40 ligand and CD28 in induction and maintenance of antiviral CD8+ effector T cell responses

    Andreasen, Susanne; Christensen, Jeanette Erbo; Marker, O; Thomsen, Allan Randrup


    and extensively, whereas vesicular stomatitis virus (VSV) spreads poorly. We found that the primary response of CD40L-/- mice toward VSV is significantly impaired; proliferation of both CD4+ and CD8+ cells is reduced 2- to 3-fold, few CD8+ cells acquire an activated phenotype, and little functional...... activity is induced. Very similar results were obtained in VSV-infected, CD28-deficient mice. In contrast, neither CD40L nor CD28 was required for induction of a primary CD8+ response toward LCMV. Surprisingly, lack of CD4+ T cells had no impact on the primary immune response toward any of the viruses......-specific CD8+ T cells on day 6 postinfection. Finally, despite the fact that the primary LCMV-specific CD8+ response is virtually unimpaired in CD40L-/- mice, their capacity to maintain CD8+ effector activity and to permanently control the infection is significantly reduced. Thus, our results demonstrate that...

  10. Tc17 CD8+ T cells potentiate Th1-mediated autoimmune diabetes in a mouse model.

    Saxena, Amit; Desbois, Sabine; Carrié, Nadège; Lawand, Myriam; Mars, Lennart T; Liblau, Roland S


    An increase in IL-17-producing CD8+ T (Tc17) cells has been reported in the peripheral blood of children with recent onset type 1 diabetes (T1D), but their contribution to disease pathogenesis is still unknown. To directly study the pathogenic potential of β cell-specific Tc17 cells, we used an experimental model of T1D based on the expression of the neo-self Ag hemagglutinin (HA) in the β cells of the pancreas. When transferred alone, the IL-17-producing HA-specific CD8+ T cells homed to the pancreatic lymph nodes without causing any pancreatic infiltration or tissue destruction. When transferred together with small numbers of diabetogenic HA-specific CD4+ T cells, a strikingly different phenotype developed. Under these conditions, Tc17 cells sustained disease progression, driving the destruction of β-islet cells, causing hyperglycemia and ultimately death. Disease progression did not correlate with functional or numerical alterations among the HA-specific CD4+ T cells. Rather, the transferred CD8+ T cells accumulated in the pancreatic islets and a considerable fraction converted, under the control of IL-12, to an IFN-γ-producing phenotype. Our data indicate that Tc17 cells are not diabetogenic but can potentiate a Th1-mediated disease. Plasticity of the Tc17 lineage is associated with transition to overt disease in this experimental model of T1D. PMID:22904307

  11. Abundant cytomegalovirus (CMV) reactive clonotypes in the CD8(+) T cell receptor alpha repertoire following allogeneic transplantation.

    Link, C S; Eugster, A; Heidenreich, F; Rücker-Braun, E; Schmiedgen, M; Oelschlägel, U; Kühn, D; Dietz, S; Fuchs, Y; Dahl, A; Domingues, A M J; Klesse, C; Schmitz, M; Ehninger, G; Bornhäuser, M; Schetelig, J; Bonifacio, E


    Allogeneic stem cell transplantation is potentially curative, but associated with post-transplantation complications, including cytomegalovirus (CMV) infections. An effective immune response requires T cells recognizing CMV epitopes via their T cell receptors (TCRs). Little is known about the TCR repertoire, in particular the TCR-α repertoire and its clinical relevance in patients following stem cell transplantation. Using next-generation sequencing we examined the TCR-α repertoire of CD8(+) T cells and CMV-specific CD8(+) T cells in four patients. Additionally, we performed single-cell TCR-αβ sequencing of CMV-specific CD8(+) T cells. The TCR-α composition of human leucocyte antigen (HLA)-A*0201 CMVpp65- and CMVIE -specific T cells was oligoclonal and defined by few dominant clonotypes. Frequencies of single clonotypes reached up to 11% of all CD8(+) T cells and half of the total CD8(+) T cell repertoire was dominated by few CMV-reactive clonotypes. Some TCR-α clonotypes were shared between patients. Gene expression of the circulating CMV-specific CD8(+) T cells was consistent with chronically activated effector memory T cells. The CD8(+) T cell response to CMV reactivation resulted in an expansion of a few TCR-α clonotypes to dominate the CD8(+) repertoires. These results warrant further larger studies to define the ability of oligoclonally expanded T cell clones to achieve an effective anti-viral T cell response in this setting. PMID:26800118

  12. Intravacuolar Membranes Regulate CD8 T Cell Recognition of Membrane-Bound Toxoplasma gondii Protective Antigen

    Jodie Lopez; Amina Bittame; Céline Massera; Virginie Vasseur; Grégory Effantin; Anne Valat; Célia Buaillon; Sophie Allart; Barbara A. Fox; Leah M. Rommereim; David J. Bzik; Guy Schoehn; Winfried Weissenhorn; Jean-François Dubremetz; Jean Gagnon


    Apicomplexa parasites such as Toxoplasma gondii target effectors to and across the boundary of their parasitophorous vacuole (PV), resulting in host cell subversion and potential presentation by MHC class I molecules for CD8cell recognition. The host-parasite interface comprises the PV limiting membrane and a highly curved, membranous intravacuolar network (IVN) of uncertain function. Here, using a cell-free minimal system, we dissect how membrane tubules are shaped by the parasite effecto...

  13. AMPKα1: A glucose sensor that controls CD8 T-cell memory

    Finlay, David


    The adenosine monophosphate-activated protein kinase (AMPK) is activated by antigen receptor signals and energy stress in T cells. In many cell types, AMPK can maintain energy homeostasis and can enforce quiescence to limit energy demands. We consequently evaluated the importance of AMPK for controlling the transition of metabolically active effector CD8 T lymphocytes to the metabolically quiescent catabolic memory T cells during the contraction phase of the immune response. We show that AMPK...

  14. A false expression of CD8 antigens on CD4+ T cells in a routine flow cytometry analysis.

    Danuta Kowalczyk


    Full Text Available The two-colour flow cytometry method applied in a routine enumeration of peripheral blood T lymphocyte subsets reveals that in some patients the entire population of CD4+ lymphocytes seems to express CD8 determinants as well. However, expression of the CD8 antigens on the cell surface is much lower in comparison with typical CD8+ cells. Moreover, in one-colour staining with an anti-CD8 antibody, cells with weak CD8 expression are not observed and only one typical population of CD8+ lymphocytes is seen. Investigating this phenomenon, we showed that after washing patient cells in RPMI before CD4/CD8 staining, the CD4+ T cell population did not show CD8 "co-expression". These results suggest that CD4+ lymphocytes, which seem to co-express CD8 antigen, in fact do not have this antigen on their surface. Moreover, after the addition of patient plasma to healthy donor cells prior to CD4/CD8 staining, a weak CD8 expression on normal CD4+ cells was noticed. Therefore we can assume that the agent(s causing this phenomenon is/are present in the plasma of some patients. Altogether, these observations suggest that this phenomenon is nonspecific and probably results from cross-linking of anti-CD8 mAbs with anti-CD4 mAbs caused by factor(s present in plasma of some patient. However, identification of that/these factor(s requires further research.

  15. Cutting Edge: ACVRL1 Signaling Augments CD8α+ Dendritic Cell Development.

    Verma, Rohit; Jaiswal, Hemant; Chauhan, Kuldeep Singh; Kaushik, Monika; Tailor, Prafullakumar


    Dendritic cells (DCs) are a collection of different subtypes, each of which is characterized by specific surface markers, gene-expression patterns, and distinct functions. Members of the IFN regulatory factor family play critical roles in DC development and functions. Recently, Irf8 was shown to activate TGF-β signaling, which led to exacerbated neuroinflammation in the experimental autoimmune encephalomyelitis mouse model. We analyzed the effect of Irf8 on TGF-β/bone morphogenetic protein pathway-specific genes in DCs and identified Acvrl1, a type I TGF-β superfamily receptor, as a gene strongly induced by Irf8 expression. Among various DC subtypes, Acvrl1 is differentially expressed in CD8α(+) DCs. ACVRL1 signaling augmented Irf8-directed classical CD8α(+) DC development. Irf8 expression is essential for plasmacytoid DC and CD8α(+) DC development, and this study demonstrates that ACVRL1 signaling plays a pivotal role whereby it suppresses plasmacytoid DC development while enhancing that of CD8α(+) DCs, thus contributing to DC diversity development. PMID:27421479

  16. Intrinsic features of the CD8α(-) dendritic cell subset in inducing functional T follicular helper cells.

    Shin, Changsik; Han, Jae-A; Choi, Bongseo; Cho, Yoon-Kyoung; Do, Yoonkyung; Ryu, Seongho


    T follicular helper (Tfh) cells, a true B cell helper, have a critical role in enhancing humoral immune responses. However, the initial differentiation of Tfh cells by dendritic cells (DCs), the most potent antigen presenting cells, has not been clearly understood, particularly in the knowledge of the two major conventional dendritic cell subsets, CD8α(+) DCs or CD8α(-) DCs. Here we demonstrated that the localization of CD8α(-) DCs in the marginal zone (MZ) bridging channels is closely associated with the induction of CXCR5(+)CCR7(low) Tfh cells. We also showed that the major source of IL-6 for inducing Tfh cells is provided from the activated CD4(+) T cells induced by CD8α(-) DCs, and IL-6 directly secreted from the DC subsets seems minor. CD8α(-) DCs were superior in inducing functional Tfh cells over other antigen presenting cells including B cells. We here observed the unknown intrinsic features of the DC subsets, suggesting the potential of utilizing the CD8α(-) DC subset as therapeutic vaccine for the regulation of humoral immune responses. PMID:26850563

  17. Differential Frequency of CD8+ T Cell Subsets in Multiple Sclerosis Patients with Various Clinical Patterns.

    Salehi, Zahra; Doosti, Rozita; Beheshti, Masoumeh; Janzamin, Ehsan; Sahraian, Mohammad Ali; Izad, Maryam


    Recent evidence points to a pathogenic role for CD8+ cytotoxic T (Tc) cells in Multiple sclerosis (MS). Based on cytokine profile, Tc cells can be divided into different subsets: IFN-γ (Tc1), IL-4 (Tc2), IL-10 (Tc10), IL-17 (Tc17), IL-21 (Tc21), IL-22 (Tc22) and TNF-α producing cells. In this study we evaluated the frequency of Tc cell subsets and the serum level of Tc17 differentiation cytokines in MS patients with different clinical patterns. We analyzed Tc cell subsets percentage in peripheral blood of relapsing-remitting (RRMS) (n = 28), secondary-progressive (SPMS) (n = 10) and primary-progressive (PPMS) (n = 4) MS patients in comparison to healthy controls (n = 15) using flow cytometry. Serum level of TGF-β, IL-6 and IL-23 were measured by ELISA. We showed elevated levels of Tc1 and Tc17 cells in SPMS and RRMS patients in relapse phase, respectively (P = 0.04). Interestingly, the percentage of TNF-α producing CD8+ T cells in relapse and remission phase of RRMS and SPMS patients were higher than controls (P = 0.01, P = 0.004, P = 0.01, respectively) and Tc21 increased in remission phase of RRMS compared to SPMS (P = 0.03). We also found higher frequency of CD8+ IFN-γ+ TNF-α+ IL-17+ T cells in relapse phase of RRMS compared to remission phase, SPMS patients and controls (P = 0.01, P = 0.004 and P = 0.02, respectively). TGF- β increased in sera of RRMS patients in remission phase (P = 0.03) and SPMS (P = 0.05) compared to healthy subjects. Increased level of Tc17 and CD8+ IFN-γ+ TNF-α+ IL-17+ T cells in relapse phase highlights the critical role of IL-17 in RRMS pathogenesis. PMID:27467597

  18. Intravacuolar Membranes Regulate CD8 T Cell Recognition of Membrane-Bound Toxoplasma gondii Protective Antigen.

    Lopez, Jodie; Bittame, Amina; Massera, Céline; Vasseur, Virginie; Effantin, Grégory; Valat, Anne; Buaillon, Célia; Allart, Sophie; Fox, Barbara A; Rommereim, Leah M; Bzik, David J; Schoehn, Guy; Weissenhorn, Winfried; Dubremetz, Jean-François; Gagnon, Jean; Mercier, Corinne; Cesbron-Delauw, Marie-France; Blanchard, Nicolas


    Apicomplexa parasites such as Toxoplasma gondii target effectors to and across the boundary of their parasitophorous vacuole (PV), resulting in host cell subversion and potential presentation by MHC class I molecules for CD8 T cell recognition. The host-parasite interface comprises the PV limiting membrane and a highly curved, membranous intravacuolar network (IVN) of uncertain function. Here, using a cell-free minimal system, we dissect how membrane tubules are shaped by the parasite effectors GRA2 and GRA6. We show that membrane association regulates access of the GRA6 protective antigen to the MHC I pathway in infected cells. Although insertion of GRA6 in the PV membrane is key for immunogenicity, association of GRA6 with the IVN limits presentation and curtails GRA6-specific CD8 responses in mice. Thus, membrane deformations of the PV regulate access of antigens to the MHC class I pathway, and the IVN may play a role in immune modulation. PMID:26628378

  19. Impact of HIV on CD8+ T cell CD57 expression is distinct from that of CMV and aging.

    Sulggi A Lee

    Full Text Available Chronic antigenic stimulation by cytomegalovirus (CMV is thought to increase "immunosenesence" of aging, characterized by accumulation of terminally differentiated CD28- CD8+ T cells and increased CD57, a marker of proliferative history. Whether chronic HIV infection causes similar effects is currently unclear.We compared markers of CD8+ T cell differentiation (e.g., CD28, CD27, CCR7, CD45RA and CD57 expression on CD28- CD8+ T cells in healthy HIV-uninfected adults with and without CMV infection and in both untreated and antiretroviral therapy (ART-suppressed HIV-infected adults with asymptomatic CMV infection.Compared to HIV-uninfected adults without CMV (n=12, those with asymptomatic CMV infection (n=31 had a higher proportion of CD28-CD8+ T cells expressing CD57 (P=0.005. Older age was also associated with greater proportions of CD28-CD8+ T cells expressing CD57 (rho: 0.47, P=0.007. In contrast, untreated HIV-infected CMV+ participants (n=55 had much lower proportions of CD28- CD8+ cells expressing CD57 than HIV-uninfected CMV+ participants (P<0.0001 and were enriched for less well-differentiated CD28- transitional memory (TTR CD8+ T cells (P<0.0001. Chronically HIV-infected adults maintaining ART-mediated viral suppression (n=96 had higher proportions of CD28-CD8+ T cells expressing CD57 than untreated patients (P<0.0001, but continued to have significantly lower levels than HIV-uninfected controls (P=0.001. Among 45 HIV-infected individuals initiating their first ART regimen, the proportion of CD28-CD8+ T cells expressing CD57 declined (P<0.0001, which correlated with a decline in percent of transitional memory CD8+ T cells, and appeared to be largely explained by a decline in CD28-CD57- CD8+ T cell counts rather than an expansion of CD28-CD57+ CD8+ T cell counts.Unlike CMV and aging, which are associated with terminal differentiation and proliferation of effector memory CD8+ T cells, HIV inhibits this process, expanding less well

  20. CD8+ T cell activation predominate early immune responses to hypercholesterolemia in Apoe-/- mice

    Björkbacka Harry


    Full Text Available Abstract Background It is well established that adaptive immune responses induced by hypercholesterolemia play an important role in the development of atherosclerosis, but the pathways involved remain to be fully characterized. In the present study we assessed immune responses to hypercholesterolemia induced by feeding Apoe-/- mice a high-fat diet for 4 or 8 weeks. Results The primary immune response in lymph nodes draining the aortic root was an increased expression of interferon (IFN-γ in CD8+CD28+ T cells, while an activation of IFN-γ expression in CD4+ T cells was observed only after 8 weeks of high-fat diet. Contrarily, spleen CD4+ T cells responded with a higher expression of IL-10. Spleen CD8+ T cells expressed both IFN-γ and IL-10 and showed enhanced proliferation when exposed to Concanavalin A. Plasma levels of IgG and IgM against oxidized LDL did not change, but the level of apolipoprotein B/IgM immune complexes was increased. Conclusion Hypercholesterolemia leads to unopposed activation of Th1 immune responses in lymph nodes draining atherosclerotic lesions, whereas Th1 activation in the spleen is balanced by a concomitant activation of Th2 cells. The activation of CD8+ T cells implies that hypercholesterolemia is associated with formation of cell autoantigens.

  1. Immediate dysfunction of vaccine-elicited CD8+ T cells primed in the absence of CD4+ T cells

    Provine, Nicholas M.; Larocca, Rafael A.; Aid, Malika; Penaloza-MacMaster, Pablo; Badamchi-Zadeh, Alexander; Borducchi, Erica N.; Yates, Kathleen B.; Abbink, Peter; Kirilova, Marinela; Ng’ang’a, David; Bramson, Jonathan; Haining, W. Nicholas; Barouch, Dan H.


    CD4+ T cell help is critical for optimal CD8+ T cell memory differentiation and maintenance in many experimental systems. Additionally, many reports have identified reduced primary CD8+ T cell responses in the absence of CD4+ T cell help, which often coincides with reduced antigen or pathogen clearance. Here we demonstrate that absence of CD4+ T cells at the time of adenovirus vector immunization of mice led to immediate impairments in early CD8+ T cell functionality and differentiation. Unhelped CD8+ T cells exhibited a reduced effector phenotype, decreased ex vivo cytotoxicity, and decreased capacity to produce cytokines. This dysfunctional state was imprinted within 3 days of immunization. Unhelped CD8+ T cells expressed elevated levels of inhibitory receptors and exhibited transcriptomic exhaustion and anergy profiles by gene set enrichment analysis. Dysfunctional, impaired effector differentiation also occurred following immunization of CD4+ T cell-deficient mice with a poxvirus vector. This study demonstrates that following priming with viral vectors, CD4+ T cell help is required to promote both the expansion and acquisition of effector functions by CD8+ T cells, which is accomplished by preventing immediate dysfunction. PMID:27448585

  2. Clonal expansions of CD8+ T cells with IL-10 secreting capacity occur during chronic Mycobacterium tuberculosis infection.

    Joshua C Cyktor

    Full Text Available The exact role of CD8(+ T cells during Mycobacterium tuberculosis (Mtb infection has been heavily debated, yet it is generally accepted that CD8(+ T cells contribute to protection against Mtb. In this study, however, we show that the Mtb-susceptible CBA/J mouse strain accumulates large numbers of CD8(+ T cells in the lung as infection progresses, and that these cells display a dysfunctional and immunosuppressive phenotype (PD-1(+, Tim-3(+, CD122(+. CD8(+ T cell expansions from the lungs of Mtb-infected CBA/J mice were also capable of secreting the immunosuppressive cytokine interleukin-10 (IL-10, although in vivo CD8(+ T cell depletion did not significantly alter Mtb burden. Further analysis revealed that pulmonary CD8(+ T cells from Mtb-infected CBA/J mice were clonally expanded, preferentially expressing T cell receptor (TcR Vβ chain 8 (8.2, 8.3 or Vβ 14. Although Vβ8(+ CD8(+ T cells were responsible for the majority of IL-10 production, in vivo depletion of Vβ8(+ did not significantly change the outcome of Mtb infection, which we hypothesize was a consequence of their dual IL-10/IFN-γ secreting profiles. Our data demonstrate that IL-10-secreting CD8(+ T cells can arise during chronic Mtb infection, although the significance of this T cell population in tuberculosis pathogenesis remains unclear.

  3. Novel CD8(+) cytotoxic T cell epitopes in bovine leukemia virus with cattle.

    Bai, Lanlan; Takeshima, Shin-Nosuke; Isogai, Emiko; Kohara, Junko; Aida, Yoko


    Bovine leukemia virus (BLV) is associated with enzootic bovine leukosis and is closely related to human T cell leukemia virus (HTLV). The cytotoxic T lymphocyte (CTL) plays a key role in suppressing the progression of disease caused by BLV. T and B cell epitopes in BLV have been studied, but CD8(+) CTL epitopes remain poorly understood. We used a library of 115 synthetic peptides covering the entirety of the Env proteins (gp51 and gp30), the Gag proteins (p15, p24, and p12), and the Tax protein of BLV to identify 11 novel CD8(+) T cell epitopes (gp51N5, gp51N11, gp51N12, gp30N5, gp30N6, gp30N8, gp30N16, tax16, tax18, tax19, and tax20) in four calves experimentally infected with BLV. The number of CD8(+) T cell epitopes that could be identified in each calf correlated with the BLV proviral load. Interestingly, among the 11 epitopes identified, only gp51N11 was capable of inducing CD8(+) T cell-mediated cytotoxicity in all four calves, but it is not a suitable vaccine target because it shows a high degree of polymorphism according to the Wu-Kabat variability index. By contrast, no CTL epitopes were identified from the Gag structural protein. In addition, several epitopes were obtained from gp30 and Tax, indicating that cellular immunity against BLV is strongly targeted to these proteins. CD8(+) CTL epitopes from gp30 and Tax were less polymorphic than epitopes from. Indeed, peptides tax16, tax18, tax19, and tax20 include a leucine-rich activation domain that encompasses a transcriptional activation domain, and the gp30N16 peptide contains a proline-rich region that interacts with a protein tyrosine phosphatase SHP1 to regulate B cell activation. Moreover, at least one CD8(+) CTL epitope derived from gp30 was identified in each of the four calves. These results indicate that BLV gp30 may be the best candidate for the development of a BLV vaccine. PMID:26552001

  4. Nasal vaccination stimulates CD8(+) T cells for potent protection against mucosal Brucella melitensis challenge.

    Clapp, Beata; Yang, Xinghong; Thornburg, Theresa; Walters, Nancy; Pascual, David W


    Brucellosis remains a significant zoonotic threat worldwide. Humans and animals acquire infection via their oropharynx and upper respiratory tract following oral or aerosol exposure. After mucosal infection, brucellosis develops into a systemic disease. Mucosal vaccination could offer a viable alternative to conventional injection practices to deter disease. Using a nasal vaccination approach, the ΔznuA B. melitensis was found to confer potent protection against pulmonary Brucella challenge, and reduce colonization of spleens and lungs by more than 2500-fold, with >50% of vaccinated mice showing no detectable brucellae. Furthermore, 10-fold more brucellae-specific, interferon-γ (IFN-γ)-producing CD8(+) T cells than CD4(+) T cells were induced in the spleen and respiratory lymph nodes. Evaluation of pulmonary and splenic CD8(+) T cells from mice vaccinated with ΔznuA B. melitensis revealed that these expressed an activated effector memory (CD44(hi)CD62L(lo)CCR7(lo)) T cells producing elevated levels of IFN-γ, tumor necrosis factor-α, perforin and granzyme B. To assess the relative importance of these increased numbers of CD8(+) T cells, CD8(-/-) mice were challenged with virulent B. melitensis, and they showed markedly increased bacterial loads in organs in contrast to similarly challenged CD4(-/-) mice. Only ΔznuA B. melitensis- and Rev-1-vaccinated CD4(-/-) and wild-type mice, not CD8(-/-) mice, were completely protected against Brucella challenge. Determination of cytokines responsible for conferring protection showed the relative importance of IFN-γ, but not interleukin-17 (IL-17). Unlike wild-type (wt) mice, IL-17 was greatly induced in IFN-γ(-/-) mice, but IL-17 could not substitute for IFN-γ's protection, although an increase in brucellae dissemination was observed upon in vivo IL-17 neutralization. These results show that nasal ΔznuA B. melitensis vaccination represents an attractive means to stimulate systemic and mucosal immune protection via CD

  5. Contribution of Herpesvirus Specific CD8 T Cells to Anti-Viral T Cell Response in Humans

    Elena Sandalova; Diletta Laccabue; Carolina Boni; Tan, Anthony T.; Katja Fink; Eng Eong Ooi; Robert Chua; Bahar Shafaeddin Schreve; Carlo Ferrari; Antonio Bertoletti


    Herpesviruses infect most humans. Their infections can be associated with pathological conditions and significant changes in T cell repertoire but evidences of symbiotic effects of herpesvirus latency have never been demonstrated. We tested the hypothesis that HCMV and EBV-specific CD8 T cells contribute to the heterologous anti-viral immune response. Volume of activated/proliferating virus-specific and total CD8 T cells was evaluated in 50 patients with acute viral infections: 20 with HBV, 1...

  6. Increased frequency of CD4 and CD8 regulatory T cells in individuals under 15 years with multibacillary leprosy.

    Camila Fernandes

    Full Text Available BACKGROUND: Leprosy is a chronic disease, caused by Mycobacterium leprae, which poses a serious public health problem worldwide. Its high incidence in people under 15 years old in Ceará state, Brazil, reflects the difficulty of its control. The spectrum of clinical manifestations is associated with the immune response developed, with the Th1 and Th2 responses being related to the paucibacillary and multibacillary forms, respectively. Regulatory T cells (Treg, which can suppress Th1 and Th2 response, have received special attention in the literature and have been associated with development of chronic infections. However, their role in leprosy in individuals under 15 years old has not yet been elucidated. We evaluated the frequency of CD4(+/CD8(+CD25(highFOXP3(+ and CD4(+/CD8(+CD25(highFOXP3(high cells in leprosy patients and household contacts, in both cases under 15 years old. METHODOLOGY/PRINCIPAL FINDINGS: PBMC from 12 patients and 17 contacts were cultured for 72 hours with anti-CD3 and anti-CD28 (activators or with activators associated with total sonicated fraction of M. leprae. After culture, the frequency of CD4(+/CD8(+ Treg was identified by flow cytometry. Cells stimulated by activators and antigen from multibacillary patients showed Treg frequencies almost two times that of the contacts: CD4(+FOXP3(+ (21.93±8.43 vs. 13.79±8.19%, p = 0.0500, CD4(+FOXP3(high (10.33±5.69 vs. 5.57±4.03%, p = 0.0362, CD8(+FOXP3(+ (13.88±9.19 vs. 6.18±5.56%, p = 0.0230 and CD8(+FOXP3(high (5.36±4.17 vs. 2.23±2.68%, p = 0.0461. Furthermore, the mean fluorescence intensity of FOXP3 in Treg was higher in multibacillary patients than in the contacts. Interestingly, there was a positive correlation of the bacillary index and number of lesions with the frequency of all Treg evaluated in patients. CONCLUSIONS/SIGNIFICANCE: We have demonstrated for the first time that multibacillary leprosy patients under 15 years old have greater CD4(+ and

  7. Generation of clinical-grade CD19-specific CAR-modified CD8+ memory stem cells for the treatment of human B-cell malignancies.

    Sabatino, Marianna; Hu, Jinhui; Sommariva, Michele; Gautam, Sanjivan; Fellowes, Vicki; Hocker, James D; Dougherty, Sean; Qin, Haiying; Klebanoff, Christopher A; Fry, Terry J; Gress, Ronald E; Kochenderfer, James N; Stroncek, David F; Ji, Yun; Gattinoni, Luca


    Long-lived, self-renewing, multipotent T memory stem cells (TSCM) can trigger profound and sustained tumor regression but their rareness poses a major hurdle to their clinical application. Presently, clinically compliant procedures to generate relevant numbers of this T-cell population are undefined. Here, we provide a strategy for deriving large numbers of clinical-grade tumor-redirected TSCM starting from naive precursors. CD8(+)CD62L(+)CD45RA(+) naive T cells enriched by streptamer-based serial-positive selection were activated by CD3/CD28 engagement in the presence of interleukin-7 (IL-7), IL-21, and the glycogen synthase-3β inhibitor TWS119, and genetically engineered to express a CD19-specific chimeric antigen receptor (CD19-CAR). These conditions enabled the generation of CD19-CAR-modified CD8(+) TSCM that were phenotypically, functionally, and transcriptomically equivalent to their naturally occurring counterpart. Compared with CD8(+) T cells generated with clinical protocols currently under investigation, CD19-CAR-modified CD8(+) TSCM exhibited enhanced metabolic fitness and mediated robust, long-lasting antitumor responses against systemic acute lymphoblastic leukemia xenografts. This clinical-grade platform provides the basis for a phase 1 trial evaluating the activity of CD19-CAR-modified CD8(+) TSCM in patients with B-cell malignancies refractory to prior allogeneic hematopoietic stem cell transplantation. PMID:27226436

  8. CD8α− Dendritic Cells Induce Antigen-Specific T Follicular Helper Cells Generating Efficient Humoral Immune Responses

    Changsik Shin


    Full Text Available Recent studies on T follicular helper (Tfh cells have significantly advanced our understanding of T cell-dependent B cell responses. However, little is known about the early stage of Tfh cell commitment by dendritic cells (DCs, particularly by the conventional CD8α+ and CD8α− DC subsets. We show that CD8α− DCs localized at the interfollicular zone play a pivotal role in the induction of antigen-specific Tfh cells by upregulating the expression of Icosl and Ox40l through the non-canonical NF-κB signaling pathway. Tfh cells induced by CD8α− DCs function as true B cell helpers, resulting in significantly increased humoral immune responses against various human pathogenic antigens, including Yersinia pestis LcrV, HIV Gag, and hepatitis B surface antigen. Our findings uncover a mechanistic role of CD8α− DCs in the initiation of Tfh cell differentiation and thereby provide a rationale for investigating CD8α− DCs in enhancing antigen-specific humoral immune responses for improving vaccines and therapeutics.

  9. Blocking of PDL-1 interaction enhances primary and secondary CD8 T cell response to herpes simplex virus-1 infection.

    Rudragouda Channappanavar

    Full Text Available The blocking of programmed death ligand-1 (PDL-1 has been shown to enhance virus-specific CD8 T cell function during chronic viral infections. Though, how PDL-1 blocking at the time of priming affects the quality of CD8 T cell response to acute infections is not well understood and remains controversial. This report demonstrates that the magnitude of the primary and secondary CD8 T cell responses to herpes simplex virus-1 (HSV-1 infection is subject to control by PDL-1. Our results showed that after footpad HSV-1 infection, PD-1 expression increases on immunodominant SSIEFARL peptide specific CD8 T cells. Additionally, post-infection, the level of PDL-1 expression also increases on CD11c+ dendritic cells. Intraperitoneal administration of anti-PDL-1 monoclonal antibody given one day prior to and three days after cutaneous HSV-1 infection, resulted in a marked increase in effector and memory CD8 T cell response to SSIEFARL peptide. This was shown by measuring the quantity and quality of SSIEFARL-specific CD8 T cells by making use of ex-vivo assays that determine antigen specific CD8 T cell function, such as intracellular cytokine assay, degranulation assay to measure cytotoxicity and viral clearance. Our results are discussed in terms of the beneficial effects of blocking PDL-1 interactions, while giving prophylactic vaccines, to generate a more effective CD8 T cell response to viral infection.

  10. STAT3 Regulates Proliferation and Survival of CD8+ T Cells: Enhances Effector Responses to HSV-1 Infection, and Inhibits IL-10+ Regulatory CD8+ T Cells in Autoimmune Uveitis

    Cheng-Rong Yu


    Full Text Available STAT3 regulates CD4+ T cell survival and differentiation. However, its effects on CD8+ T cells are not well understood. Here, we show that in comparison to WT CD8+ T cells, STAT3-deficient CD8+ T cells exhibit a preactivated memory-like phenotype, produce more IL-2, proliferate faster, and are more sensitive to activation-induced cell death (AICD. The enhanced proliferation and sensitivity to AICD correlated with downregulation of class-O forkhead transcription factors (FoxO1, FoxO3A, , , Bcl-2, OX-40, and upregulation of FasL, Bax, and Bad. We examined whether STAT3-deficient CD8+ T cells can mount effective response during herpes simplex virus (HSV-1 infection and experimental autoimmune uveitis (EAU. Compared to WT mice, HSV-1-infected STAT3-deficient mice (STAT3KO produced less IFN- and virus-specific KLRG-1+ CD8+ T cells. STAT3KO mice are also resistant to EAU and produced less IL-17-producing Tc17 cells. Resistance of STAT3KO to EAU correlated with marked expansion of IL-10-producing regulatory CD8+ T cells (CD8-Treg implicated in recovery from autoimmune encephalomyelitis. Thus, increases of IL-6-induced STAT3 activation observed during inflammation may inhibit expansion of CD8-Tregs, thereby impeding recovery from uveitis. These results suggest that STAT3 is a potential therapeutic target for upregulating CD8+ T cell-mediated responses to viruses and suggest the successful therapeutic targeting of STAT3 as treatment for uveitis, derived, in part, from promoting CD8-Treg expansion.

  11. Changes in CD4+, CD8+, CD4+ CD8+, and Immunoglobulin M-Positive Peripheral Blood Mononuclear Cells of Postweaning Multisystemic Wasting Syndrome-Affected Pigs and Age-Matched Uninfected Wasted and Healthy Pigs Correlate with Lesions and Porcine Circovirus Type 2 Load in Lymphoid Tissues

    Darwich, Laila; Segalés, Joaquim; Domingo, Mariano; Mateu, Enric


    Forty-one 8- to 12-week-old wasted pigs were selected from several conventional farms with histories of postweaning multisystemic wasting syndrome (PMWS) and classified into two groups according to their porcine circovirus type 2 (PCV2) infection status, as determined by in situ hybridization (ISH). Twenty-four pigs tested positive for PCV2 (PCV2-positive group), while 17 pigs tested negative for PCV2 (PCV2-negative group). In addition, eight uninfected healthy pigs from an experimental farm ...

  12. Blimp-1-mediated CD4 T cell exhaustion causes CD8 T cell dysfunction during chronic toxoplasmosis.

    Hwang, SuJin; Cobb, Dustin A; Bhadra, Rajarshi; Youngblood, Ben; Khan, Imtiaz A


    CD8, but not CD4, T cells are considered critical for control of chronic toxoplasmosis. Although CD8 exhaustion has been previously reported in Toxoplasma encephalitis (TE)-susceptible model, our current work demonstrates that CD4 not only become exhausted during chronic toxoplasmosis but this dysfunction is more pronounced than CD8 T cells. Exhausted CD4 population expressed elevated levels of multiple inhibitory receptors concomitant with the reduced functionality and up-regulation of Blimp-1, a transcription factor. Our data demonstrates for the first time that Blimp-1 is a critical regulator for CD4 T cell exhaustion especially in the CD4 central memory cell subset. Using a tamoxifen-dependent conditional Blimp-1 knockout mixed bone marrow chimera as well as an adoptive transfer approach, we show that CD4 T cell-intrinsic deletion of Blimp-1 reversed CD8 T cell dysfunction and resulted in improved pathogen control. To the best of our knowledge, this is a novel finding, which demonstrates the role of Blimp-1 as a critical regulator of CD4 dysfunction and links it to the CD8 T cell dysfunctionality observed in infected mice. The critical role of CD4-intrinsic Blimp-1 expression in mediating CD4 and CD8 T cell exhaustion may provide a rational basis for designing novel therapeutic approaches. PMID:27481131

  13. Induction of CD8+ Regulatory T Cells Protects Macaques against SIV Challenge

    Wei Lu


    Full Text Available Efforts to develop a vaccine against HIV have so far met with limited success. Given that CD4+ T cell activation drives the initial burst of viral replication, we explored in macaques whether an oral vaccine comprised of Lactobacillus plantarum, a commensal bacterium that favors immune tolerance, and inactivated simian immunodeficiency virus mac239 (SIVmac239 would induce CD4+ T cell unresponsiveness/tolerance toward SIV antigens and thereby prevent the establishment of SIV infection. The tolerogenic vaccine induced MHC-Ib/E-restricted CD8+ regulatory T cells (Tregs that suppressed SIV-harboring CD4+ T cell activation and ex vivo SIV replication in 15 of 16 animals without inducing SIV-specific antibodies or cytotoxic T lymphocytes. Of 16 macaques that were intrarectally challenged with SIVmac239 or heterologous strain SIVB670, 15 were sterilely protected. In four macaques that were rechallenged intravenously, plasma SIV levels peaked slightly and then dropped to undetectable levels, although the animals subsequently harbored intracellular SIV DNA. Infusion of CD8 antibodies confirmed the role of CD8+ Tregs in preventing/suppressing SIV in vivo. These findings suggest a new avenue of research toward developing an HIV-1 vaccine.

  14. Characterization of Diabetogenic CD8+ T Cells: IMMUNE THERAPY WITH METABOLIC BLOCKADE.

    Garyu, Justin W; Uduman, Mohamed; Stewart, Alex; Rui, Jinxiu; Deng, Songyan; Shenson, Jared; Staron, Matt M; Kaech, Susan M; Kleinstein, Steven H; Herold, Kevan C


    Type 1 diabetes mellitus is caused by the killing of insulin-producing β cells by CD8+T cells. The disease progression, which is chronic, does not follow a course like responses to conventional antigens such as viruses, but accelerates as glucose tolerance deteriorates. To identify the unique features of the autoimmune effectors that may explain this behavior, we analyzed diabetogenic CD8+ T cells that recognize a peptide from the diabetes antigen IGRP (NRP-V7-reactive) in prediabetic NOD mice and compared them to others that shared their phenotype (CD44(+)CD62L(lo)PD-1(+)CXCR3(+)) but negative for diabetes antigen tetramers and to LCMV (lymphocytic choriomeningitis)-reactive CD8+ T cells. There was an increase in the frequency of the NRP-V7-reactive cells coinciding with the time of glucose intolerance. The T cells persisted in hyperglycemic NOD mice maintained with an insulin pellet despite destruction of β cells. We compared gene expression in the three groups of cells compared with the other two subsets of cells, and the NRP-V7-reactive cells exhibited gene expression of memory precursor effector cells. They had reduced cellular proliferation and were less dependent on oxidative phosphorylation. When prediabetic NOD mice were treated with 2-deoxyglucose to block aerobic glycolysis, there was a reduction in the diabetes antigen versus other cells of similar phenotype and loss of lymphoid cells infiltrating the islets. In addition, treatment of NOD mice with 2-deoxyglucose resulted in improved β cell granularity. These findings identify a link between metabolic disturbances and autoreactive T cells that promotes development of autoimmune diabetes. PMID:26994137

  15. Integration of B cells and CD8+ T in the protective regulation of systemic epithelial inflammation

    Wei, Bo; McPherson, Michael; Turovskaya, Olga; Velazquez, Peter; Fujiwara, Daisuke; Brewer, Sarah; Braun, Jonathan


    Mechanisms that control abnormal CD4+ T cell-mediated tissue damage are a significant factor in averting and resolving chronic inflammatory epithelial diseases. B cells can promote such immunoregulation, and this is thought to involve interaction with MHC II- or CD1-restricted regulatory T cells. The purpose of this study is to genetically define the interacting cells targeted by protective B cells, and to elucidate their regulatory mechanisms in CD4+ T cell inflammation. Transfer of Gαi2−/− CD3+ T cells into lymphopenic mice causes a dose-dependent multi-organ inflammatory disease including the skin, intestine, and lungs. Disease activity is associated with elevated levels of serum TNF-α and IFN-γ and an activated IL-17 producing CD4+ T cell population. Mesenteric node B cells from wild type mice suppress disease activity, serum cytokine expression, and levels of CD4+ T cells producing TNF-α, IFN-γ, and IL-17. The protective function of B cells requires genetic sufficiency of IL-10, MHC I and TAP1. Regulatory B cells induce the expansion and activation of CD8+ T cells, which is correlated with disease protection. These results demonstrate that CD8+ T cells can ameliorate lymphopenic systemic inflammatory disease, through peptide/MHC I-dependent B cell interaction. PMID:18282744

  16. STAT3 Regulates Proliferation and Survival of CD8+ T Cells: Enhances Effector Responses to HSV-1 Infection, and Inhibits IL-10+ Regulatory CD8+ T Cells in Autoimmune Uveitis

    Cheng-Rong Yu; Dambuza, Ivy M.; Yong-Jun Lee; Frank, Gregory M.; Egwuagu, Charles E.


    STAT3 regulates CD4+ T cell survival and differentiation. However, its effects on CD8+ T cells are not well understood. Here, we show that in comparison to WT CD8+ T cells, STAT3-deficient CD8+ T cells exhibit a preactivated memory-like phenotype, produce more IL-2, proliferate faster, and are more sensitive to activation-induced cell death (AICD). The enhanced proliferation and sensitivity to AICD correlated with downregulation of class-O forkhead transcription factors (FoxO1, FoxO3A), p21wa...

  17. The closely related CD103+ dendritic cells (DCs and lymphoid-resident CD8+ DCs differ in their inflammatory functions.

    Zhijun Jiao

    Full Text Available Migratory CD103+ and lymphoid-resident CD8+ dendritic cells (DCs share many attributes, such as dependence on the same transcription factors, cross-presenting ability and expression of certain surface molecules, such that it has been proposed they belong to a common sub-lineage. The functional diversity of the two DC types is nevertheless incompletely understood. Here we reveal that upon skin infection with herpes simplex virus, migratory CD103+ DCs from draining lymph nodes were more potent at inducing Th17 cytokine production by CD4+ T cells than CD8+ DCs. This superior capacity to drive Th17 responses was also evident in CD103+ DCs from uninfected mice. Their differential potency to induce Th17 differentiation was reflected by higher production of IL-1β and IL-6 by CD103+ DCs compared with CD8+ DCs upon stimulation. The two types of DCs from isolated lymph nodes also differ in expression of certain pattern recognition receptors. Furthermore, elevated levels of GM-CSF, typical of those found in inflammation, substantially increased the pool size of CD103+ DCs in lymph nodes and skin. We argue that varied levels of GM-CSF may explain the contrasting reports regarding the positive role of GM-CSF in regulating development of CD103+ DCs. Together, we find that these two developmentally closely-related DC subsets display functional differences and that GM-CSF has differential effect on the two types of DCs.

  18. Regulatory T cells prevent CD8 T cell maturation by inhibiting CD4 Th cells at tumor sites.

    Chaput, Nathalie; Darrasse-Jèze, Guillaume; Bergot, Anne-Sophie; Cordier, Corinne; Ngo-Abdalla, Stacie; Klatzmann, David; Azogui, Orly


    Natural regulatory T cells (Tregs) are present in high frequencies among tumor-infiltrating lymphocytes and in draining lymph nodes, supposedly facilitating tumor development. To investigate their role in controlling local immune responses, we analyzed intratumoral T cell accumulation and function in the presence or absence of Tregs. Tumors that grew in normal BALB/c mice injected with the 4T1 tumor cell line were highly infiltrated by Tregs, CD4 and CD8 cells, all having unique characteristics. Most infiltrating Tregs expressed low levels of CD25Rs and Foxp3. They did not proliferate even in the presence of IL-2 but maintained a strong suppressor activity. CD4 T cells were profoundly anergic and CD8 T cell proliferation and cytotoxicity were severely impaired. Depletion of Tregs modified the characteristics of tumor infiltrates. Tumors were initially invaded by activated CD4(+)CD25(-) T cells, which produced IL-2 and IFN-gamma. This was followed by the recruitment of highly cytotoxic CD8(+) T cells at tumor sites leading to tumor rejection. The beneficial effect of Treg depletion in tumor regression was abrogated when CD4 helper cells were also depleted. These findings indicate that the massive infiltration of tumors by Tregs prevents the development of a successful helper response. The Tregs in our model prevent Th cell activation and subsequent development of efficient CD8 T cell activity required for the control of tumor growth. PMID:17911581

  19. Akt1 and -2 inhibition diminishes terminal differentiation and enhances central memory CD8+ T-cell proliferation and survival

    Abu Eid, Rasha; Friedman, Kevin M; Mkrtichyan, Mikayel; Walens, Andrea; King, William; Janik, John; Khleif, Samir N


    The CD8 + T-cell response comprises terminally differentiated effector cells and antigen-experienced memory T cells. The latter encompass central (TCM) and effector (TEM) memory cells. TCM cells are superior in their protection against viral and bacterial challenges and mediation of antitumor immunity due to their higher proliferative ability upon antigen re-encounter. Defining a mechanism to enhance TCM cells and delay terminal differentiation of CD8 + T cells is crucial for cancer immune th...

  20. Perivascular Arrest of CD8+ T Cells Is a Signature of Experimental Cerebral Malaria.

    Tovah N Shaw

    Full Text Available There is significant evidence that brain-infiltrating CD8+ T cells play a central role in the development of experimental cerebral malaria (ECM during Plasmodium berghei ANKA infection of C57BL/6 mice. However, the mechanisms through which they mediate their pathogenic activity during malaria infection remain poorly understood. Utilizing intravital two-photon microscopy combined with detailed ex vivo flow cytometric analysis, we show that brain-infiltrating T cells accumulate within the perivascular spaces of brains of mice infected with both ECM-inducing (P. berghei ANKA and non-inducing (P. berghei NK65 infections. However, perivascular T cells displayed an arrested behavior specifically during P. berghei ANKA infection, despite the brain-accumulating CD8+ T cells exhibiting comparable activation phenotypes during both infections. We observed T cells forming long-term cognate interactions with CX3CR1-bearing antigen presenting cells within the brains during P. berghei ANKA infection, but abrogation of this interaction by targeted depletion of the APC cells failed to prevent ECM development. Pathogenic CD8+ T cells were found to colocalize with rare apoptotic cells expressing CD31, a marker of endothelial cells, within the brain during ECM. However, cellular apoptosis was a rare event and did not result in loss of cerebral vasculature or correspond with the extensive disruption to its integrity observed during ECM. In summary, our data show that the arrest of T cells in the perivascular compartments of the brain is a unique signature of ECM-inducing malaria infection and implies an important role for this event in the development of the ECM-syndrome.

  1. Priming of CD8 T Cells by Adenoviral Vectors Is Critically Dependent on B7 and Dendritic Cells but Only Partially Dependent on CD28 Ligation on CD8 T Cells

    Nielsen, Karen N; Steffensen, Maria A; Christensen, Jan P;


    Adenoviral vectors have long been forerunners in the development of effective CD8 T cell-based vaccines; therefore, it is imperative that we understand the factors controlling the induction of robust and long-lasting transgene-specific immune responses by these vectors. In this study, we investig......Adenoviral vectors have long been forerunners in the development of effective CD8 T cell-based vaccines; therefore, it is imperative that we understand the factors controlling the induction of robust and long-lasting transgene-specific immune responses by these vectors. In this study, we...... investigated the organ sites, molecules, and cell subsets that play a critical role in the priming of transgene-specific CD8 T cells after vaccination with a replication-deficient adenoviral vector. Using a human adenovirus serotype 5 (Ad5) vector and genetically engineered mice, we found that CD8(+) and/or CD......103(+) dendritic cells in the draining lymph node played a critical role in the priming of Ad5-induced CD8 T cell responses. Moreover, we found that CD80/86, but not CD28, was essential for efficient generation of both primary effectors and memory CD8 T cells. Interestingly, the lack of CD28...

  2. Increased percentage of L-selectin+ and ICAM-1+ peripheral blood CD4+/CD8+ T cells in active Graves' ophthalmopathy.

    Alina Bakunowicz-Lazarczyk


    Full Text Available The purpose of the study was to evaluate the percentage of CD4+/CD8+ peripheral T cells expressing CD62L+ and CD54+ in patients with Graves' disease and to assess if these estimations could be helpful as markers of active ophthalmopathy. The study was carried out in 25 patients with Graves' disease (GD divided into 3 groups: 1/ 8 patients with active Graves' ophthalmopathy (GO (CAS 3-6, GO complaints pound 1 year, 2/ 9 patients with hyperthyroid GD without symptoms of ophthalmopathy (GDtox and 3/ 8 patients with euthyroid GD with no GO symptoms (GDeu. The control group consisted of 15 healthy volunteers age and sex matched to groups 1-3. The expression of lymphocyte adhesion molecules was evaluated by using three-color flow cytometry. In GO group the percentage of CD8+CD54+, CD8+CD62L+, CD4+CD54+ and CD4+CD62L+ T cells was significantly higher as compared to controls (p<0.001, p<0.05, p<0.01, p<0.001 respectively. The percentage of CD8+CD54+ T lymphocytes was also elevated in GO group in comparison to hyperthyroid GD patients (p< 0.05. CD4+CD62L+ and CD8+CD54+ percentages were also increased in GDtox and GDeu as compared to controls. We found a positive correlation between the TSHRab concentration and the percentage of CD8+CD62L+ T cells in all studied groups (r= 0.39, p<0.05 and between the TSHRab level and CAS (r= 0.77, p<0.05. The increased percentage of CD8+CD54+ and CD8+CD62L+ T cells in patients with Graves' ophthalmopathy may be used as a marker of immune inflammation activity.

  3. Incomplete effector/memory differentiation of antigen-primed CD8+ T cells in gene gun DNA-vaccinated mice

    Bartholdy, Christina; Stryhn, Anette; Hansen, Nils Jacob Vest;


    DNA vaccination is an efficient way to induce CD8+ T cell memory, but it is still unclear to what extent such memory responses afford protection in vivo. To study this, we induced CD8+ memory responses directed towards defined viral epitopes, using DNA vaccines encoding immunodominant MHC class I...

  4. PD-L1 Expression on Retrovirus-Infected Cells Mediates Immune Escape from CD8+ T Cell Killing.

    Ilseyar Akhmetzyanova


    Full Text Available Cytotoxic CD8+ T Lymphocytes (CTL efficiently control acute virus infections but can become exhausted when a chronic infection develops. Signaling of the inhibitory receptor PD-1 is an important mechanism for the development of virus-specific CD8+ T cell dysfunction. However, it has recently been shown that during the initial phase of infection virus-specific CD8+ T cells express high levels of PD-1, but are fully competent in producing cytokines and killing virus-infected target cells. To better understand the role of the PD-1 signaling pathway in CD8+ T cell cytotoxicity during acute viral infections we analyzed the expression of the ligand on retrovirus-infected cells targeted by CTLs. We observed increased levels of PD-L1 expression after infection of cells with the murine Friend retrovirus (FV or with HIV. In FV infected mice, virus-specific CTLs efficiently eliminated infected target cells that expressed low levels of PD-L1 or that were deficient for PD-L1 but the population of PD-L1high cells escaped elimination and formed a reservoir for chronic FV replication. Infected cells with high PD-L1 expression mediated a negative feedback on CD8+ T cells and inhibited their expansion and cytotoxic functions. These findings provide evidence for a novel immune escape mechanism during acute retroviral infection based on PD-L1 expression levels on virus infected target cells.

  5. Viral sequestration of antigen subverts cross presentation to CD8(+ T cells.

    Eric F Tewalt


    Full Text Available Virus-specific CD8(+ T cells (T(CD8+ are initially triggered by peptide-MHC Class I complexes on the surface of professional antigen presenting cells (pAPC. Peptide-MHC complexes are produced by two spatially distinct pathways during virus infection. Endogenous antigens synthesized within virus-infected pAPC are presented via the direct-presentation pathway. Many viruses have developed strategies to subvert direct presentation. When direct presentation is blocked, the cross-presentation pathway, in which antigen is transferred from virus-infected cells to uninfected pAPC, is thought to compensate and allow the generation of effector T(CD8+. Direct presentation of vaccinia virus (VACV antigens driven by late promoters does not occur, as an abortive infection of pAPC prevents production of these late antigens. This lack of direct presentation results in a greatly diminished or ablated T(CD8+ response to late antigens. We demonstrate that late poxvirus antigens do not enter the cross-presentation pathway, even when identical antigens driven by early promoters access this pathway efficiently. The mechanism mediating this novel means of viral modulation of antigen presentation involves the sequestration of late antigens within virus factories. Early antigens and cellular antigens are cross-presented from virus-infected cells, as are late antigens that are targeted to compartments outside of the virus factories. This virus-mediated blockade specifically targets the cross-presentation pathway, since late antigen that is not cross-presented efficiently enters the MHC Class II presentation pathway. These data are the first to describe an evasion mechanism employed by pathogens to prevent entry into the cross-presentation pathway. In the absence of direct presentation, this evasion mechanism leads to a complete ablation of the T(CD8+ response and a potential replicative advantage for the virus. Such mechanisms of viral modulation of antigen presentation

  6. Human and Mouse CD8+CD25+FOXP3+ Regulatory T Cells at Steady State and during Interleukin-2 Therapy

    Churlaud, Guillaume; Pitoiset, Fabien; Jebbawi, Fadi; Lorenzon, Roberta; Bellier, Bertrand; Rosenzwajg, Michelle; Klatzmann, David


    International audience In addition to CD4+ regulatory T cells (Tregs), CD8+ suppressor T cells are emerging as an important subset of regulatory T cells. Diverse populations of CD8+ T cells with suppressive activities have been described. Among them, a small population of CD8+CD25+FOXP3+ T cells is found both in mice and humans. In contrast to thymic-derived CD4+CD25+FOXP3+ Tregs, their origin and their role in the pathophysiology of autoimmune diseases (AIDs) are less understood. We repor...

  7. IL-15 induces unspecific effector functions in human peptide-specific CD8+ T-cell cultures

    Lyngstrand, S T; Würtzen, P A; Ødum, N; Nissen, Mogens Holst; Röpke, C


    Antigen (Ag)-specific CD8+ T cells are a major host defence against viral infections. In the present study, we generated human CD8+ T-cell lines specific towards influenza matrix peptide (IMP)-pulsed Ag-presenting cells. We compared the effect of interleukin-2 (IL-2) and IL-15 on the proliferation...... cultures. Secondary IMP-specific CD8+ T cells were generated by the addition of IL-2 during two cycles of restimulation. From the third restimulation, identical CTL cultures were expanded with either IL-2 or IL-15 in parallel. Cell expansion as well as Ag specificity was considerably reduced after a 5 day...

  8. Role of CD4+ and CD8+ T cells in murine resistance to street rabies virus.

    Perry, L. L.; Lodmell, D L


    Mice of the SJL/J and BALB/cByJ inbred strains are naturally resistant to street rabies virus (SRV) injected via the intraperitoneal route. To determine the cellular mechanism of resistance, monoclonal antibodies specific for CD4+ or CD8+ subsets of T cells were used to deplete the respective cell population in SRV-infected animals. Elimination of CD4+ T-helper cells abrogated the production of immunoglobulin G (IgG) neutralizing antibodies in response to rabies virus infection and reversed t...

  9. ELISPOTs Produced by CD8 and CD4 Cells Follow Log Normal Size Distribution Permitting Objective Counting

    Alexey Y. Karulin


    Full Text Available Each positive well in ELISPOT assays contains spots of variable sizes that can range from tens of micrometers up to a millimeter in diameter. Therefore, when it comes to counting these spots the decision on setting the lower and the upper spot size thresholds to discriminate between non-specific background noise, spots produced by individual T cells, and spots formed by T cell clusters is critical. If the spot sizes follow a known statistical distribution, precise predictions on minimal and maximal spot sizes, belonging to a given T cell population, can be made. We studied the size distributional properties of IFN-γ, IL-2, IL-4, IL-5 and IL-17 spots elicited in ELISPOT assays with PBMC from 172 healthy donors, upon stimulation with 32 individual viral peptides representing defined HLA Class I-restricted epitopes for CD8 cells, and with protein antigens of CMV and EBV activating CD4 cells. A total of 334 CD8 and 80 CD4 positive T cell responses were analyzed. In 99.7% of the test cases, spot size distributions followed Log Normal function. These data formally demonstrate that it is possible to establish objective, statistically validated parameters for counting T cell ELISPOTs.

  10. CD45/CD8 myeloid histioid antigen and plasma cell antibody immune response in a case of malignant melanoma

    Ana Maria Abreu-Velez


    Full Text Available The immune response in metastatic melanoma is not well established and therefore is of particular interest to test for recruitment of immune cells to the tumor. A 46-year-old Caucasian female was evaluated for an asymptomatic right forearm mass. The lesion had been present for at least 4 years and had become painful 4 months ago. Biopsies for hematoxylin and eosin (H and E staining, as well as immunohistochemical analysis were performed on the primary tumor and on sentinel lymph nodes. The H and E staining was consistent with metastatic melanoma. Positive staining was noted on the tumor cells with S-100, Mart-1/Melan A/CD63, PNL2, HMB45, and tyrosinase. Peritumoral and intratumoral inflammatory cells stained positive for CD8, CD45, PCNA, myeloid histoid antigen, antihuman plasma cell antibody, and focal BRCA1. The staining patterns of CD8/CD45, myeloid histoid antigen and plasma cell antibody on inflammatory cells around the melanoma cells suggest an unusual type of immune response.