151
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Peacock CD, Kim SK, Welsh RM. Attrition of virus-specific memory CD8+ T cells during reconstitution of lymphopenic environments. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2003; 171:655-63. [PMID: 12847230 DOI: 10.4049/jimmunol.171.2.655] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Viruses can cause a severe lymphopenia early in infection and a subsequent, lasting loss of pre-existing CD8(+) memory T cells. We therefore questioned how well virus Ag-specific memory CD8(+) T cells could reconstitute mice rendered lymphopenic as a consequence of genetics, irradiation, or viral or poly(I:C)-induced cytokines. In each case, reconstitution of the CD8(+) compartment was associated with limited division of virus-specific memory T cells and a reduction in their proportion. This indicates that foreign Ag-experienced CD44(high)CD8(+) memory T cells may respond differently to homeostatic signals than other CD44(high)CD8(+) cells, and that events inducing lymphopenia may lead to a permanent reduction in T cell memory.
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Affiliation(s)
- Craig D Peacock
- Department of Pathology, University of Massachusetts Medical Center, Worcester, MA 01655, USA
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152
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Liu H, Andreansky S, Diaz G, Turner SJ, Wodarz D, Doherty PC. Quantitative analysis of long-term virus-specific CD8+-T-cell memory in mice challenged with unrelated pathogens. J Virol 2003; 77:7756-63. [PMID: 12829815 PMCID: PMC161950 DOI: 10.1128/jvi.77.14.7756-7763.2003] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The consequences for the long-term maintenance of virus-specific CD8+-T-cell memory have been analyzed experimentally for sequential respiratory infections with readily eliminated (influenza virus) and persistent (gammaherpesvirus 68 [gammaHV68]) pathogens. Sampling a broad range of tissue sites established that the numbers of CD8+ T cells specific for the prominent influenza virus D(b)NP(366) epitope were reduced by about half in mice that had been challenged 100 days previously with gammaHV68, though the prior presence of a large CD8+ D(b)NP366+ population caused no selective defect in the gammaHV68-specific CD8+ K(b)p79+ response. Conversely, mice that had been primed and boosted to generate substantial gammaHV68-specific CD8+ D(b)p56+ populations did not show any decrease in prevalence for this set of CD8+ memory cytotoxic T lymphocytes (CTL) at 200 days after respiratory exposure to an influenza A virus. However, in both experiments, the total magnitude of the CD8+-T-cell pool was significantly diminished in those that had been infected with gammaHV68 and the influenza A virus. The broader implications of these findings, especially under conditions of repeated exposure to unrelated pathogens, are explored with a mathematical model which emphasizes that the immune effector and memory "phenome" is a function of the overall infection experience of the individual.
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Affiliation(s)
- Haiyan Liu
- Department of Immunology, St. Jude Children's Research Hospital, 332 North Lauderdale, Memphis, TN 38105, USA
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153
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Geginat J, Lanzavecchia A, Sallusto F. Proliferation and differentiation potential of human CD8+ memory T-cell subsets in response to antigen or homeostatic cytokines. Blood 2003; 101:4260-6. [PMID: 12576317 DOI: 10.1182/blood-2002-11-3577] [Citation(s) in RCA: 408] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Four human CD8+ T-cell subsets, naive (CCR7+CD45RA+), central memory (TCM, CCR7+CD45RA-), effector memory (TEM, CCR7-CD45RA-), and CD45RA+ effector memory cells (TEMRA, CCR7-CD45RA+) were compared for their capacity to proliferate and differentiate in response to antigen or homeostatic cytokines. Cytokine responsiveness and interleukin-15 receptor expression were low in naive T cells and progressively increased from TCM to TEM and TEMRA. In contrast, the capacity to accumulate in response to T-cell receptor (TCR) or cytokine stimulation showed a reciprocal pattern and was associated with resistance to cell death and Bcl-2 expression. Whereas all TCR-stimulated cells acquired a CD45RA-CCR7- phenotype, cytokine-stimulated cells maintained their phenotype with the exception of TCM cells, which expressed CCR7, CD45RA, and perforin in various combinations. Single CD8+ TCM cells, but not TEM cells, could be expanded with cytokines, and the obtained clones displayed several distinct phenotypes, suggesting that TCM cells are heterogeneous. Consistently, CCR4 expression in the CD8+ TCM pool discriminated CCR4+ type 2 polarized cells (Tc2) and CCR4-CTL precursors. Finally, ex vivo bromodeoxyuridine (BrdU) incorporation experiments revealed that memory subsets have different in vivo proliferation rates, with CCR4-TCM having the highest turnover and TEMRA the lowest. These results show that human CD8+ memory T-cell subsets have different proliferation and differentiation potentials in vitro and in vivo. Furthermore, they suggest that TEMRA cells are generated from a TCM subset upon homeostatic proliferation in the absence of antigen.
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Affiliation(s)
- Jens Geginat
- Institute for Research in Biomedicine, Bellinzona, Switzerland.
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154
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Ely KH, Cauley LS, Roberts AD, Brennan JW, Cookenham T, Woodland DL. Nonspecific recruitment of memory CD8+ T cells to the lung airways during respiratory virus infections. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2003; 170:1423-9. [PMID: 12538703 DOI: 10.4049/jimmunol.170.3.1423] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Previous studies have shown that heterologous viral infections have a significant impact on pre-existing memory T cell populations in secondary lymphoid organs through a combination of cross-reactive and bystander effects. However, the impact of heterologous viral infections on effector/memory T cells in peripheral sites is not well understood. In this study, we have analyzed the impact of a heterologous influenza virus infection on Sendai virus-specific CD8(+) effector/memory cells present in the lung airways. The data show a transient increase in the numbers of Sendai virus nucleoprotein 324-332/K(b)-specific CD8(+) memory T cells in the airways of the influenza-infected mice peaking around day 4 postinfection. Intratracheal transfer studies and 5-bromo-2'-deoxyuridine incorporation demonstrate that this increase is due to the recruitment of resting memory cells into the airways. In addition, the data show that these immigrating memory cells are phenotypically distinct from the resident memory T cells of the lung airways. A similar influx of nonproliferating Sendai virus nucleoprotein 324-332/K(b)-specific CD8(+) memory T cells is also induced by a secondary (homologous) infection with Sendai virus. Together, these data suggest that inflammation can accelerate memory T cell migration to nonlymphoid tissues and is a part of the normal recall response during respiratory infections.
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155
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Peacock CD, Xu W, Stepp SE, Welsh RM. Dynamics of Ly49 expressing cytotoxic lymphocyte subsets in response to virus infection. Microbes Infect 2002; 4:1481-90. [PMID: 12505520 DOI: 10.1016/s1286-4579(02)00031-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Viral infections induce first a loss and then an increase in natural killer (NK) and CD8(+) T cells. NK cells expressing Ly49G2 were selectively expanded by several viruses and poly I:C. CD8(+) T cells expressing Ly49G2 were selectively expanded by poly I:C and participated in the antigen-specific response to lymphocytic choriomeningitis virus.
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Affiliation(s)
- Craig D Peacock
- Department of Pathology, University of Massachusetts Medical Center, 55 Lake Avenue North, Worcester, MA 01655, USA
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156
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Smith DK, Dudani R, Pedras-Vasconcelos JA, Chapdelaine Y, van Faassen H, Sad S. Cross-reactive antigen is required to prevent erosion of established T cell memory and tumor immunity: a heterologous bacterial model of attrition. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 169:1197-206. [PMID: 12133940 DOI: 10.4049/jimmunol.169.3.1197] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Induction and maintenance of T cell memory is critical for the control of intracellular pathogens and tumors. Memory T cells seem to require few "maintenance signals," though often such studies are done in the absence of competing immune challenges. Conversely, although attrition of CD8(+) T cell memory has been characterized in heterologous viral models, this is not the case for bacterial infections. In this study, we demonstrate attrition of T cell responses to the intracellular pathogen Listeria monocytogenes (LM) following an immune challenge with a second intracellular bacterium, Mycobacterium bovis (bacillus Calmette-Guérin, BCG). Mice immunized with either LM or recombinant LM (expressing OVA; LM-OVA), develop a potent T cell memory response. This is reflected by peptide-specific CTL, IFN-gamma production, and frequency of IFN-gamma-secreting T cells to native or recombinant LM Ags. However, when the LM-infected mice are subsequently challenged with BCG, there is a marked reduction in the LM-specific T cell responses. These reductions are directly attributable to the effects on CD4(+) and CD8(+) T cells and the data are consistent with a loss of LM-specific T cells, not anergy. Attrition of the Ag (OVA)-specific T cell response is prevented when LM-OVA-immunized mice are challenged with a subsequent heterologous pathogen (BCG) expressing OVA, demonstrating memory T cell dependence on Ag. Although the reduction of the LM-specific T cell response did not impair protection against a subsequent LM rechallenge, for the first time, we show that T cell attrition can result in the reduction of Ag-specific antitumor (B16-OVA) immunity previously established with LM-OVA immunization.
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Affiliation(s)
- Dean K Smith
- Laboratory of Cellular Immunology, Institute for Biological Sciences, National Research Council, Ottawa, Ontario, Canada
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157
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Drobyski WR, Komorowski R, Logan B, Gendelman M. Role of the passive apoptotic pathway in graft-versus-host disease. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 169:1626-33. [PMID: 12133993 DOI: 10.4049/jimmunol.169.3.1626] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Donor T cells have been shown to undergo apoptosis during graft-vs-host disease (GVHD). Although active apoptosis mediated through Fas/Fas ligand interactions has been implicated in GVHD, little is known about the role of the passive apoptotic pathway. To examine this question, we compared the ability of normal donor T cells and T cells overexpressing the antiapoptotic protein, Bcl-x(L), to mediate alloreactive responses in vitro and lethal GVHD in vivo. In standard MLCs, T cells that overexpressed Bcl-x(L) had significantly higher proliferative responses but no difference in cytokine phenotype. Overexpression of Bcl-x(L) prolonged survival of both resting and alloactivated CD4(+) and CD8(+) T cells as assessed by quantitative flow cytometry, accounting for the higher proliferative responses. Analysis of engraftment in murine transplantation experiments demonstrated an increase in donor T cell chimerism in animals transplanted with Bcl-x(L) T cells, suggesting that overexpression of Bcl-x(L) prolonged T cell survival in vivo as well. Notably, transplantation of Bcl-x(L) T cells into nonirradiated F(1) recipients also significantly exacerbated GVHD as assessed by mortality and pathological damage in the gastrointestinal tract. However, when mice were irradiated no difference in GVHD mortality was observed between animals transplanted with wild-type and Bcl-x(L) T cells. These data demonstrate that the passive apoptotic pathway plays a role in the homeostatic survival of transplanted donor T cells. Moreover, the susceptibility of donor T cells to undergo passive apoptosis is a significant factor in determining GVHD severity under noninflammatory but not inflammatory conditions.
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Affiliation(s)
- William R Drobyski
- Department of Medicine and Bone Marrow Transplant Program, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
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158
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Affiliation(s)
- J M McNally
- Department of Pathology, Program in Immunology and Virology, University of Massachusetts Medical Center, Worcester, MA 01655, USA
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159
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Kim SK, Brehm MA, Welsh RM, Selin LK. Dynamics of memory T cell proliferation under conditions of heterologous immunity and bystander stimulation. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 169:90-8. [PMID: 12077233 DOI: 10.4049/jimmunol.169.1.90] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
By examining adoptively transferred CSFE-labeled lymphocytic choriomeningitis virus (LCMV)-immune donor T cells in Thy-1 congenic hosts inoculated with viruses or with the cytokine inducer poly(I:C), strikingly different responses of bona fide memory T cells were found in response to different stimuli. Poly(I:C) (cytokine) stimulation caused a limited synchronized division of memory CD8 T cells specific to each of five LCMV epitopes, with no increase and sometimes a loss in number, and no change in their epitope hierarchy. Homologous LCMV infection caused more than seven divisions of T cells specific for each epitope, with dramatic increases in number and minor changes in hierarchy. Infections with the heterologous viruses Pichinde and vaccinia (VV) caused more than seven divisions and increases in number of T cells specific to some putatively cross-reactive but not other epitopes and resulted in substantial changes in the hierarchy of the LCMV-specific T cells. Hence, there can be memory T cell division without proliferation (i.e., increase in cell number) in the absence of Ag and division with proliferation in the presence of Ag from homologous or heterologous viruses. Heterologous protective immunity between viruses is not necessarily reciprocal, given that LCMV protects against VV but VV does not protect against LCMV. VV elicited proliferation of LCMV-induced CD8 and CD4 T cells, whereas LCMV did not elicit proliferation of VV-induced T cells. Thus, depending on the pathogen and the sequence of infection, a heterologous agent may selectively stimulate the memory pool in patterns consistent with heterologous immunity.
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Affiliation(s)
- Sung-Kwon Kim
- Department of Pathology, University of Massachusetts, Worcester, MA 01655, USA
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160
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Murakami M, Sakamoto A, Bender J, Kappler J, Marrack P. CD25+CD4+ T cells contribute to the control of memory CD8+ T cells. Proc Natl Acad Sci U S A 2002; 99:8832-7. [PMID: 12084927 PMCID: PMC124384 DOI: 10.1073/pnas.132254399] [Citation(s) in RCA: 182] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Previously we demonstrated that IL-15 and IL-2 control the number of memory CD8+ T cells in mice. IL-15 induces, and IL-2 suppresses the division of these cells. Here we show that CD25+CD4+ regulatory T cells play an important role in the IL-2-mediated control of memory phenotype CD8+ T cell number. In animals, the numbers of CD25+CD4+ T cells were inversely correlated with the numbers of memory phenotype CD8+ T cells with age. Treatment with anti-IL-2 caused CD25+CD4+ T cells to disappear and, concurrently, increased the numbers of memory phenotype CD8+ T cells. This increase in the numbers of CD8+ memory phenotype T cells was not manifest in animals lacking CD4+ cells. Importantly, adoptive transfer of CD25+CD4+ T cells significantly reduced division of memory phenotype CD8+ T cells. Thus, we conclude that CD25+CD4+ T cells are involved in the IL-2-mediated inhibition of memory CD8+ T cell division and that IL-2 controls memory phenotype CD8+ T cell numbers at least in part through maintenance of the CD25+CD4+ T cell population.
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Affiliation(s)
- Masaaki Murakami
- Howard Hughes Medical Institute, Integrated Department of Immunology, National Jewish Medical and University of Colorado Health Sciences Center, Denver, CO 80206, USA
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161
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Abstract
Memory T cells that are specific for one virus can become activated during infection with an unrelated heterologous virus, and might have roles in protective immunity and immunopathology. The course of each infection is influenced by the T-cell memory pool that has been laid down by a host's history of previous infections, and with each successive infection, T-cell memory to previously encountered agents is modified. Here, we discuss evidence from studies in mice and humans that shows the importance of this phenomenon in determining the outcome of infection.
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Affiliation(s)
- Raymond M Welsh
- Department of Pathology, University of Massachusetts Medical School, Worcester 01655, USA
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162
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Abstract
Homeostatic control of CD8 T cell populations is essential for defense against infectious pathogens. Our understanding of the mechanisms that control naïve, effector and memory T cell populations in the intact animal has increased significantly over the last several years. There have been some surprises. For example, peripheral tissues have been found to harbor unexpectedly large numbers of effector memory T cells. Also unexpected was the finding of programmed T cell proliferation following very brief exposure to antigen. These and other recent advances are summarized in the following review.
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Affiliation(s)
- Roman A Tuma
- Infectious Disease Service, Department of Medicine, Immunology Program, Sloan-Kettering Institute, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA.
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163
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Kasaian MT, Whitters MJ, Carter LL, Lowe LD, Jussif JM, Deng B, Johnson KA, Witek JS, Senices M, Konz RF, Wurster AL, Donaldson DD, Collins M, Young DA, Grusby MJ. IL-21 limits NK cell responses and promotes antigen-specific T cell activation: a mediator of the transition from innate to adaptive immunity. Immunity 2002; 16:559-69. [PMID: 11970879 DOI: 10.1016/s1074-7613(02)00295-9] [Citation(s) in RCA: 379] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
IFNalpha/beta, IL-12, and IL-15 regulate NK cell activation and expansion, but signals triggering resolution of the NK response upon induction of adaptive immunity remain to be defined. We now report that IL-21, a product of activated T cells, may serve this function. Mice lacking IL-21R (IL-21R(-/-)) had normal NK cell development but no detectable responses to IL-21. IL-21 enhanced cytotoxic activity and IFNgamma production by activated murine NK cells but did not support their viability, thus limiting their duration of activation. Furthermore, IL-21 blocked IL-15-induced expansion of resting NK cells, thus preventing the initiation of further innate responses. In contrast, IL-21 enhanced the proliferation, IFNgamma production, and cytotoxic function of CD8(+) effector T cells in an allogeneic MLR. These observations suggest that IL-21 promotes the transition between innate and adaptive immunity.
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MESH Headings
- Animals
- Apoptosis/immunology
- CD8-Positive T-Lymphocytes/immunology
- Cytotoxicity, Immunologic
- Female
- Hyaluronan Receptors/immunology
- Immunity, Active
- Immunity, Innate
- Interleukin-15/immunology
- Interleukin-21 Receptor alpha Subunit
- Interleukins/immunology
- Interleukins/pharmacology
- Isoantigens/immunology
- Killer Cells, Natural/cytology
- Killer Cells, Natural/immunology
- Lymphocyte Activation/immunology
- Lymphocyte Count
- Male
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Knockout
- Receptors, Interleukin/genetics
- Receptors, Interleukin/immunology
- Receptors, Interleukin-2/biosynthesis
- Receptors, Interleukin-21
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164
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Holtappels R, Grzimek NKA, Thomas D, Reddehase MJ. Early gene m18, a novel player in the immune response to murine cytomegalovirus. J Gen Virol 2002; 83:311-316. [PMID: 11807223 DOI: 10.1099/0022-1317-83-2-311] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The identification of all antigenic peptides encoded by a pathogen, its T cell 'immunome', is a research aim for rational vaccine design. Screening of proteome-spanning peptide libraries or computational prediction is used to identify antigenic peptides recognized by CD8 T cells. Based on their high coding capacity, cytomegaloviruses (CMVs) could specify numerous antigenic peptides. Yet, current evidence indicates that the memory CD8 T cell response in a given haplotype is actually focused on a few viral proteins. CMVs actively interfere with antigen processing and presentation by the expression of immune evasion proteins. In the case of murine CMV (mCMV), these proteins are effectual in the early (E) phase of the virus replication cycle and should thus preclude the presentation of peptides derived from E proteins. Notably, the m18 gene is here added to a growing list of mCMV E genes that encode antigenic peptides in spite of the E phase immune evasion strategies of the virus.
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Affiliation(s)
- Rafaela Holtappels
- Institute for Virology, Johannes Gutenberg University, Hochhaus am Augustusplatz, 55101 Mainz, Germany1
| | - Natascha K A Grzimek
- Institute for Virology, Johannes Gutenberg University, Hochhaus am Augustusplatz, 55101 Mainz, Germany1
| | - Doris Thomas
- Institute for Virology, Johannes Gutenberg University, Hochhaus am Augustusplatz, 55101 Mainz, Germany1
| | - Matthias J Reddehase
- Institute for Virology, Johannes Gutenberg University, Hochhaus am Augustusplatz, 55101 Mainz, Germany1
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165
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Holtappels R, Thomas D, Podlech J, Reddehase MJ. Two antigenic peptides from genes m123 and m164 of murine cytomegalovirus quantitatively dominate CD8 T-cell memory in the H-2d haplotype. J Virol 2002; 76:151-64. [PMID: 11739681 PMCID: PMC135724 DOI: 10.1128/jvi.76.1.151-164.2002] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The importance of CD8 T cells for the control of cytomegalovirus (CMV) infection has raised interest in the identification of immunogenic viral proteins as candidates for vaccination and cytoimmunotherapy. The final aim is to determine the viral "immunome" for any major histocompatibility complex class I molecule by antigenicity screening of proteome-derived peptides. For human CMV, there is a limitation to this approach: the T cells used as responder cells for peptide screening are usually memory cells that have undergone in vivo selection. On this basis, pUL83 (pp65) and pUL123 (IE1 or pp68 to -72) were classified as immunodominant proteins. It is an open question whether this limited "memory immunome" really reflects the immunogenic potential of the human CMV proteome. Here we document an analogous focus of the memory repertoire on two proteins of murine CMV. Specifically, ca. 80% of all memory CD8 T cells in the spleen as well as in persisting pulmonary infiltrates were found to be specific for the known IE1 peptide 168YPHFMPTNL176 and for the peptide 257AGPPRYSRI265, newly defined here, derived from open reading frame m164. Notably, CD8 T-cell lines of both specificities protected against acute infection upon adoptive transfer. In contrast, the natural immune response to acute infection in draining lymph nodes and in the lungs indicated a somewhat broader specificity repertoire. We conclude that the low number of antigenic peptides identified so far for CMVs reflects a focused memory repertoire, and we predict that more antigenic peptides will be disclosed by analysis of the acute immune response.
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Affiliation(s)
- Rafaela Holtappels
- Institute for Virology, Johannes Gutenberg University, 55101 Mainz, Germany
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