scholarly journals CD4 T Cell Epitope Specificity and Cytokine Potential Are Preserved as Cells Transition from the Lung Vasculature to Lung Tissue following Influenza Virus Infection

2018 ◽  
Vol 92 (13) ◽  
pp. e00377-18 ◽  
Author(s):  
Anthony DiPiazza ◽  
Nathan Laniewski ◽  
Ajitanuj Rattan ◽  
David J. Topham ◽  
Jim Miller ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Lung Tissue ◽  
Cd4 T Cells ◽  
Cell Epitope ◽  
Influenza Virus Infection ◽  
Cd4 T Cell ◽  
Pulmonary Vasculature ◽  
T Cell Epitope ◽  
Epitope Specificity

ABSTRACT Pulmonary CD4 T cells are critical in respiratory virus control, both by delivering direct effector function and through coordinating responses of other immune cells. Recent studies have shown that following influenza virus infection, virus-specific CD4 T cells are partitioned between pulmonary vasculature and lung tissue. However, very little is known about the peptide specificity or functional differences of CD4 T cells within these two compartments. Using a mouse model of influenza virus infection in conjunction with intravascular labeling in vivo, the cell surface phenotype, epitope specificity, and functional potential of the endogenous polyclonal CD4 T cell response was examined by tracking nine independent CD4 T cell epitope specificities. These studies revealed that tissue-localized CD4 cells were globally distinct from vascular cells in expression of markers associated with transendothelial migration, residency, and micropositioning. Despite these differences, there was little evidence for remodeling of the viral epitope specificity or cytokine potential as cells transition from vasculature to the highly inflamed lung tissue. Our studies also distinguished cells in the pulmonary vasculature from peripheral circulating CD4 T cells, providing support for the concept that the pulmonary vasculature does not simply reflect circulating cells that are trapped within the narrow confines of capillary vessels but rather is enriched in transitional cells primed in the draining lymph node that have specialized potential to enter the lung tissue. IMPORTANCE CD4 T cells convey a multitude of functions in immunity to influenza, including those delivered in the lymph node and others conveyed by CD4 T cells that leave the lymph node, enter the blood, and extravasate into the lung tissue. Here, we show that the transition of recently primed CD4 cells detected in the lung vasculature undergo profound changes in expression of markers associated with tissue localization as they establish residence in the lung. However, this transition does not edit CD4 T cell epitope specificity or the cytokine potential of the CD4 T cells. Thus, CD4 T cells that enter the infected lung can convey diverse functions and have a sufficiently broad viral antigen specificity to detect the complex array of infected cells within the infected tissue, offering the potential for more effective protective function.

Identification of T Cell Epitope of ADAMTS13 in Thrombotic Thrombocytopenic Purpura Patients

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 106-106 ◽  
Author(s):  
Laurent Gilardin ◽  
Sandrine Delignat ◽  
Bernard Maillere ◽  
Bagirath Gangadharan ◽  
Ivan Peyron ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Line ◽  
Cd4 T Cells ◽  
Binding Capacity ◽  
Cell Epitope ◽  
Interferon Γ ◽  
Cd4 T Cell ◽  
T Cell Epitope ◽  
T Cell Lines

Abstract Introduction: Thrombotic Thrombocytopenic Purpura (TTP) results from the development of auto-antibodies directed against A Disintegrin And Metalloproteinase with Thrombospondin type 1 repeats, 13th member (A13). The implication of CD4+ T-cells in the pathogenesis of the disease is suggested by the existence of a restriction to HLA DRB1*11 allele and by the isotype switch of the antibodies. However, T-cell autoimmune response to A13 and the properties of CD4+ T-cells from TTP patients have never been studied. Here, we determined the immunodominant T-cell epitope of A13 in TTP patients. Methods: Using the IEDB website, we predicted in silico the immunodominant peptides of A13 based on their binding capacity to HLA DR11 haplotype. Subsequently, these peptides were synthesized and validated in vitro for their binding capacity to purified HLA-DR11 molecules using an ELISA competitive assay. The peptides that bound with the best capacity to HLA-DRB1*11 molecule were then tested for their recognition by human CD4+ T-cells from HLA DRB1*11 healthy donors and patients, at diagnosis or in remission. To this end, CD4+ T-cells were repetitively stimulated with HLA-DRB1*11 monocyte-derived dendritic cells loaded with the peptides and T-cell line were generated after amplification of interferon-γ secreting cells selected upon stimulation. The effect of individual peptide on activation of the established CD4+ T-cell line was assessed by interferon-γ (IFNγ) ELISPOT. Next, we evaluated the promiscuous HLA-binding capacity of the DRB1*11 identified peptides using the same method in HLA DRB1*01 TTP patients. Finally, in order to validate the involvement of these peptides in an immune response toward A13 in vivo, we immunized a humanized HLA DRB1*01-transgenic H-2 class I-/class II-knockout mouse with full length recombinant human A13 (rhA13). We then generated A13-specific T-cell hybridomas restricted to human HLA DRB1*01 and investigated whether the peptides previously identified were recognized by the hybridomas. Results A first list of 48 peptides with reliable predicted binding scores was elaborated through IEDB analysis. Of these, twenty-one peptides demonstrated a high binding capacity to HLA DRB1*11 molecules on ELISA competitive assay. These were selected to stimulate human CD4+ T-cells and we generated CD4+ T-cell lines from HLA DRB1*11 healthy donors and patients (n=5). Six A13 derived peptides were able to activate CD4+ T-cell lines, as revealed by IFNγ secretion by ELISPOT. The peptides were identified to be located within different domains of the protein but more particularly in the spacer and CUB2 domains. Interestingly, two of the identified peptides demonstrated promiscuity based on their ability to activate a CD4+ T-cell line we generated from a HLA DRB1*01 TTP patient. In parallel studies, using HLA DRB1*01 transgenic mice immunized with rhA13, we generated A13-specific T-cell hybridomas. The screening of their specificity allowed us to identify only one A13 derived peptide. The sequence of the peptide, located within the CUB2 domain, was precisely determined, it is promiscuous between DRB1*01 and DRB1*11 haplotype and represents the immunodominant CD4+ T-cell epitope of ADAMTS13. Conclusion: We identified several undescribed CD4+T-cell epitopes of A13 in HLA DRB1*1101 patients. They are located in different domains of the protein, particularly in the spacer and CUB2 domains. One of them, located in the CUB2 domain, is promiscuous to HLA DRB1*0101 and responsible for the immunodominant response to A13. The results we obtained, lead us to generate the tools to study the specific cells involved in the origin of the physiopathological process of the disease. Disclosures Coppo: Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees.

scholarly journals Transgenic expression of a T cell epitope in Strongyloides ratti reveals that helminth-specific CD4+ T cells constitute both Th2 and Treg populations

2021 ◽  
Vol 17 (7) ◽  
pp. e1009709
Author(s):  
Bonnie Douglas ◽  
Yun Wei ◽  
Xinshe Li ◽  
Annabel Ferguson ◽  
Li-Yin Hung ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd4 T Cells ◽  
Transgenic Line ◽  
Fluorescent Protein ◽  
Cell Epitope ◽  
Cd4 T Cell ◽  
Cell Phenotype ◽  
T Cell Epitope ◽  
Antigen Specificity

Helminths are distinct from microbial pathogens in both size and complexity, and are the likely evolutionary driving force for type 2 immunity. CD4+ helper T cells can both coordinate worm clearance and prevent immunopathology, but issues of T cell antigen specificity in the context of helminth-induced Th2 and T regulatory cell (Treg) responses have not been addressed. Herein, we generated a novel transgenic line of the gastrointestinal nematode Strongyloides ratti expressing the immunodominant CD4+ T cell epitope 2W1S as a fusion protein with green fluorescent protein (GFP) and FLAG peptide in order to track and study helminth-specific CD4+ T cells. C57BL/6 mice infected with this stable transgenic line (termed Hulk) underwent a dose-dependent expansion of activated CD44hiCD11ahi 2W1S-specific CD4+ T cells, preferentially in the lung parenchyma. Transcriptional profiling of 2W1S-specific CD4+ T cells isolated from mice infected with either Hulk or the enteric bacterial pathogen Salmonella expressing 2W1S revealed that pathogen context exerted a dominant influence over CD4+ T cell phenotype. Interestingly, Hulk-elicited 2W1S-specific CD4+ T cells exhibited both Th2 and Treg phenotypes and expressed high levels of the EGFR ligand amphiregulin, which differed greatly from the phenotype of 2W1S-specific CD4+ T cells elicited by 2W1S-expressing Salmonella. While immunization with 2W1S peptide did not enhance clearance of Hulk infection, immunization did increase total amphiregulin production as well as the number of amphiregulin-expressing CD3+ cells in the lung following Hulk infection. Altogether, this new model system elucidates effector as well as immunosuppressive and wound reparative roles of helminth-specific CD4+ T cells. This report establishes a new resource for studying the nature and function of helminth-specific T cells.

scholarly journals CD4 T Cell Responses in Lung Tissue and Their Role in Th2 Protective Immunity

2021 ◽  
Author(s):  
◽  
Marina Catherine Goudie Harvie
Keyword(s):  
T Cells ◽  
Lymph Node ◽  
T Cell ◽  
Lung Tissue ◽  
Cd4 T Cells ◽  
Lymphoid Tissue ◽  
Protective Immunity ◽  
Cd4 T Cell ◽  
Cell Responses ◽  
Memory Cd4 T Cells

<p>The acquisition of protective immunity is a critical feature of the immune system. It is the unique ability of the adaptive immune response to generate and maintain long-lived antigen specific memory cells, which is the key to preventing reinfection and achieving the goal of protective immunity. The importance of secondary lymphoid tissue (such as lymph nodes) as a site of effector CD4 T cell responses and the generation, dissemination and maintenance of memory CD4 T cells is well accepted. However, a key research area needing investigation is the basic biology of the CD4 T cell, particularly the recirculation, distribution and maintenance of CD4 T cells at sites throughout the body. To address these issues we used Nippostrongylus brasiliensis as a model of CD4 mediated protective immunity, combined with G4/IL-4 reporter mice. We show that the lung environment is critical for the priming of CD4 T cells and conferring protective immunity. In contrast to others we find no protective role for the CD4 T cell population of the skin and only a minor role for the population within the gut. In a separate study we used the drug fingolimod (FTY720) to block the cellular trafficking between lymph node and lung tissue during immune responses. Interestingly, our findings show that protection against N. brasiliensis infection is maintained when CD4 T cell recirculation between the lung and lymph node is blocked. Furthermore, we reveal that peripheral lung residing CD4 T cells are sufficient for conferring protective immunity in the N. brasiliensis model, generating support for the model of effector lymphoid tissue. When N. brasiliensis experienced CD4 T cells were localised to the lung by intranasal adoptive transfer they were able to confer protection against infection in otherwise naive animals, as early as 48 hours post infection. The most striking finding of this work is the discovery that memory CD4 T cells residing in the lung that are sufficient to confer protection against reinfection. Identifying the factors in the lung and lymph node that induce and support this CD4 T cell subset will be an important area of future research given its high relevance to the design of vaccines against parasite infections.</p>

scholarly journals Memory CD4 T Cells Direct Protective Responses to Influenza Virus in the Lungs through Helper-Independent Mechanisms

2010 ◽  
Vol 84 (18) ◽  
pp. 9217-9226 ◽  
Author(s):  
John R. Teijaro ◽  
David Verhoeven ◽  
Carly A. Page ◽  
Damian Turner ◽  
Donna L. Farber
Keyword(s):  
T Cells ◽  
Influenza Virus ◽  
T Cell ◽  
Cd4 T Cells ◽  
Natural Infection ◽  
Influenza Virus Infection ◽  
Cd4 T Cell ◽  
Virus Challenge ◽  
Specific Memory ◽  
Memory Cd4 T Cells

ABSTRACT Memory CD4 T cells specific for influenza virus are generated from natural infection and vaccination, persist long-term, and recognize determinants in seasonal and pandemic influenza virus strains. However, the protective potential of these long-lived influenza virus-specific memory CD4 T cells is not clear, including whether CD4 T-cell helper or effector functions are important in secondary antiviral responses. Here we demonstrate that memory CD4 T cells specific for H1N1 influenza virus directed protective responses to influenza virus challenge through intrinsic effector mechanisms, resulting in enhanced viral clearance, recovery from sublethal infection, and full protection from lethal challenge. Mice with influenza virus hemagglutinin (HA)-specific memory CD4 T cells or polyclonal influenza virus-specific memory CD4 T cells exhibited protection from influenza virus challenge that occurred in the presence of CD8-depleting antibodies in B-cell-deficient mice and when CD4 T cells were transferred into lymphocyte-deficient RAG2−/− mice. Moreover, the presence of memory CD4 T cells mobilized enhanced T-cell recruitment and immune responses in the lung. Neutralization of gamma interferon (IFN-γ) production in vivo abrogated memory CD4 T-cell-mediated protection from influenza virus challenge by HA-specific memory T cells and heterosubtypic protection by polyclonal memory CD4 T cells. Our results indicate that memory CD4 T cells can direct enhanced protection from influenza virus infection through mobilization of immune effectors in the lung, independent of their helper functions. These findings have important implications for the generation of universal influenza vaccines by promoting long-lived protective CD4 T-cell responses.

scholarly journals Intranasal nanoparticle vaccination elicits a persistent, polyfunctional CD4 T cell response in the murine lung specific for a highly conserved influenza antigen that are sufficient to mediate protection from influenza virus challenge

2021 ◽  
Author(s):  
Sean A. Nelson ◽  
Thamotharampillai Dileepan ◽  
Amy Rasley ◽  
Marc K. Jenkins ◽  
Nicholas O. Fischer ◽  
...  
Keyword(s):  
T Cells ◽  
Influenza Virus ◽  
T Cell ◽  
Cd4 T Cells ◽  
Critical Role ◽  
Influenza Virus Infection ◽  
T Cell Response ◽  
Cd4 T Cell ◽  
Vaccine Platform

Lung-localized CD4 T cells play a critical role in the control of influenza virus infection and can provide broadly protective immunity. However, current influenza vaccination strategies primarily target influenza hemagglutinin (HA) and are administered peripherally to induce neutralizing antibodies. We have used an intranasal vaccination strategy targeting the highly conserved influenza nucleoprotein (NP) to elicit broadly protective lung localized CD4 T cell responses. The vaccine platform consists of a self-assembling nanolipoprotein particle (NLP) linked to NP with an adjuvant. We have evaluated the functionality, in vivo localization and persistence of T cells elicited. Our study revealed that intranasal vaccination elicits a polyfunctional subset of lung-localized CD4 T cells that persist long term. A subset of these lung CD4 T cells localize to the airway, where they can act as early responders following encounter with cognate antigen. Polyfunctional CD4 cells isolated from airway and lung tissue produce significantly more effector cytokines IFNγ and TNFα as well as cytotoxic functionality. When adoptively transferred to naïve recipients, CD4 T cells from NLP:NP immunized lung were sufficient to mediate 100% survival from lethal challenge with H1N1 influenza virus. Importance Exploiting new, more efficacious strategies to potentiate influenza-specific immune responses is important, particularly for at-risk populations. We have demonstrated the promise of direct intranasal protein vaccination to establish long-lived immunity in the lung with CD4 T cells that possess features and positioning in the lung that are associated with both immediate and long-term immunity, as well as demonstrating direct protective potential.

Sign in / Sign up

Export Citation Format

Share Document