scholarly journals Surviving older patients show preserved cellular and humoral immunological memory several months after SARS-CoV-2 infection

2021 ◽  
Author(s):  
Alejandra García-Torre ◽  
Eva Bueno-García ◽  
Rocío López-Martínez ◽  
Beatriz Rioseras ◽  
Marco Antonio Moro-García ◽  
...  
Keyword(s):  
T Lymphocytes ◽  
Immune Responses ◽  
B Lymphocyte ◽  
Immunological Memory ◽  
Specific Memory ◽  
Great Heterogeneity ◽  
Ifn Γ ◽  
Humoral Responses ◽  
Lymphocyte Responses ◽  
Memory T Lymphocytes

Abstract Understanding how older people respond to SARS-CoV-2 is critical if we are to confront the COVID-19 pandemic and establish effective vaccination strategies. Immunosenescence reduces the ability to respond to neoantigens and may compromise the life of infected individuals. Here, we analysed the immunological memory to SARS-CoV-2 in 102 recovered patients aged over 60 years several months after the infection had been resolved. Specific memory T lymphocytes against the virus were measured by IFN-γ and granzyme B release by ELISpot; memory B lymphocyte responses were quantified by detection of anti-S IgG1 producer cells by ELISpot and anti-S and anti-N antibodies were determined by ELISA. Memory T lymphocytes were found in peripheral blood of most of the studied donors, more than seven months after the infection in some of them. Fewer patients maintained memory B lymphocytes, but antibodies, mainly anti-S, were highly durable and positively correlated with T responses. More robust humoral responses were found in patients who had more severe symptoms and had been admitted to hospital. We concluded that specific immunity against SARS-CoV-2 is effectively preserved regardless of age, despite the great heterogeneity of their immune responses, and that memory T lymphocytes and anti-S IgG might be more durable than memory B cells and anti-N IgG.

scholarly journals CD4+ T Lymphocytes from Calves Immunized withAnaplasma marginale Major Surface Protein 1 (MSP1), a Heteromeric Complex of MSP1a and MSP1b, Preferentially Recognize the MSP1a Carboxyl Terminus That Is Conserved among Strains

2001 ◽  
Vol 69 (11) ◽  
pp. 6853-6862 ◽  
Author(s):  
Wendy C. Brown ◽  
Guy H. Palmer ◽  
Harris A. Lewin ◽  
Travis C. McGuire
Keyword(s):  
T Lymphocytes ◽  
T Lymphocyte ◽  
Protective Immunity ◽  
B Lymphocyte ◽  
Surface Protein ◽  
Specific Response ◽  
Major Surface Protein ◽  
Ifn Γ ◽  
Major Surface ◽  
Lymphocyte Responses

ABSTRACT Native major surface protein 1 (MSP1) of the ehrlichial pathogenAnaplasma marginale induces protective immunity in calves challenged with homologous and heterologous strains. MSP1 is a heteromeric complex of a single MSP1a protein covalently associated with MSP1b polypeptides, of which at least two (designated MSP1F1 and MSP1F3) in the Florida strain are expressed. Immunization with recombinant MSP1a and MSP1b alone or in combination fails to provide protection. The protective immunity in calves immunized with native MSP1 is associated with the development of opsonizing and neutralizing antibodies, but CD4+ T-lymphocyte responses have not been evaluated. CD4+ T lymphocytes participate in protective immunity to ehrlichial pathogens through production of gamma interferon (IFN-γ), which promotes switching to high-affinity immunoglobulin G (IgG) and activation of phagocytic cells to produce nitric oxide. Thus, an effective vaccine for A. marginaleand related organisms should contain both T- and B-lymphocyte epitopes that induce a strong memory response that can be recalled upon challenge with homologous and heterologous strains. This study was designed to determine the relative contributions of MSP1a and MSP1b proteins, which contain both variant and conserved amino acid sequences, in stimulating memory CD4+ T-lymphocyte responses in calves immunized with native MSP1. Peripheral blood mononuclear cells and CD4+ T-cell lines from MSP1-immunized calves proliferated vigorously in response to the immunizing strain (Florida) and heterologous strains of A. marginale. The conserved MSP1-specific response was preferentially directed to the carboxyl-terminal region of MSP1a, which stimulated high levels of IFN-γ production by CD4+ T cells. In contrast, there was either weak or no recognition of MSP1b proteins. Paradoxically, all calves developed high titers of IgG antibodies to both MSP1a and MSP1b polypeptides. These findings suggest that in calves immunized with MSP1 heteromeric complex, MSP1a-specific T lymphocytes may provide help to MSP1b-specific B lymphocytes. The data provide a basis for determining whether selected MSP1a CD4+ T-lymphocyte epitopes and selected MSP1a and MSP1b B-lymphocyte epitopes presented on the same molecule can stimulate a protective immune response.

scholarly journals NK T Cells Contribute to Expansion of CD8+ T Cells and Amplification of Antiviral Immune Responses to Respiratory Syncytial Virus

2002 ◽  
Vol 76 (9) ◽  
pp. 4294-4303 ◽  
Author(s):  
Teresa R. Johnson ◽  
Seokmann Hong ◽  
Luc Van Kaer ◽  
Yasuhiko Koezuka ◽  
Barney S. Graham
Keyword(s):  
T Cells ◽  
Respiratory Syncytial Virus ◽  
T Lymphocytes ◽  
Immune Responses ◽  
Natural Killer ◽  
Viral Clearance ◽  
Normal Numbers ◽  
Nk T Cells ◽  
Ifn Γ ◽  
Syncytial Virus

ABSTRACT CD1d-deficient mice have normal numbers of T lymphocytes and natural killer cells but lack Vα14+ natural killer T cells. Respiratory syncytial virus (RSV) immunopathogenesis was evaluated in 129×C57BL/6, C57BL/6, and BALB/c CD1d−/− mice. CD8+ T lymphocytes were reduced in CD1d−/− mice of all strains, as shown by cell surface staining and major histocompatibility complex class I tetramer analysis, and resulted in strain-specific alterations in illness, viral clearance, and gamma interferon (IFN-γ) production. Transient activation of NK T cells in CD1d+/+ mice by α-GalCer resulted in reduced illness and delayed viral clearance. These data suggest that early IFN-γ production and efficient induction of CD8+-T-cell responses during primary RSV infection require CD1d-dependent events. We also tested the ability of α-GalCer as an adjuvant to modulate the type 2 immune responses induced by RSV glycoprotein G or formalin-inactivated RSV immunization. However, immunized CD1-deficient or α-GalCer-treated wild-type mice did not exhibit diminished disease following RSV challenge. Rather, some disease parameters, including cytokine production, eosinophilia, and viral clearance, were increased. These findings indicate that CD1d-dependent NK T cells play a role in expansion of CD8+ T cells and amplification of antiviral responses to RSV.

scholarly journals P16-53. Distinct subsets of memory T lymphocytes from HIV-1-infected subjects secrete IFN-γ and IL-2 in response to novel CD4+ T-cell HIV-1 epitopes

Retrovirology ◽  
2009 ◽  
Vol 6 (S3) ◽  
Author(s):  
S Fonseca ◽  
A Coutinho-Silva ◽  
D Rodrigues ◽  
L Marti ◽  
C Moreira-Filho ◽  
...  
Keyword(s):  
T Cell ◽  
T Lymphocytes ◽  
Cd4 T Cell ◽  
Ifn Γ ◽  
Memory T Lymphocytes ◽  
Hiv 1

scholarly journals Magnitude and Phenotype of Cellular Immune Responses Elicited by Recombinant Adenovirus Vectors and Heterologous Prime-Boost Regimens in Rhesus Monkeys

2008 ◽  
Vol 82 (10) ◽  
pp. 4844-4852 ◽  
Author(s):  
Jinyan Liu ◽  
Bonnie A. Ewald ◽  
Diana M. Lynch ◽  
Matthew Denholtz ◽  
Peter Abbink ◽  
...  
Keyword(s):  
Immune Responses ◽  
T Lymphocyte ◽  
Rhesus Monkeys ◽  
Recombinant Adenovirus ◽  
Interleukin 2 ◽  
Cellular Immune Responses ◽  
Tnf Α ◽  
Ifn Γ ◽  
Cellular Immune ◽  
Lymphocyte Responses

ABSTRACT Recombinant adenovirus serotype 5 (rAd5) vaccine vectors for human immunodeficiency virus type 1 (HIV-1) and other pathogens have been shown to elicit antigen-specific cellular immune responses. Rare serotype rAd vectors have also been constructed to circumvent preexisting anti-Ad5 immunity and to facilitate the development of novel heterologous rAd prime-boost regimens. Here we show that rAd5, rAd26, and rAd48 vectors elicit qualitatively distinct phenotypes of cellular immune responses in rhesus monkeys and can be combined as potent heterologous prime-boost vaccine regimens. While rAd5-Gag induced primarily gamma interferon-positive (IFN-γ+) and IFN-γ+/tumor necrosis factor alpha+ (TNF-α+) T-lymphocyte responses, rAd26-Gag and rAd48-Gag induced higher proportions of interleukin-2+ (IL-2+) and polyfunctional IFN-γ+/TNF-α+/IL-2+ T-lymphocyte responses. Priming with the rare serotype rAd vectors proved remarkably effective for subsequent boosting with rAd5 vectors. These data demonstrate that the rare serotype rAd vectors elicited T-lymphocyte responses that were phenotypically distinct from those elicited by rAd5 vectors and suggest the functional relevance of polyfunctional CD8+ and CD4+ T-lymphocyte responses. Moreover, qualitative differences in cellular immune responses may prove critical in determining the overall potency of heterologous rAd prime-boost regimens.

scholarly journals Th-1-Type Cytotoxic CD8+ T-Lymphocyte Responses to Simian Immunodeficiency Virus (SIV) Are a Consistent Feature of Natural SIV Infection in Sooty Mangabeys

2006 ◽  
Vol 80 (6) ◽  
pp. 2771-2783 ◽  
Author(s):  
Zichun Wang ◽  
Benjamin Metcalf ◽  
Ruy M. Ribeiro ◽  
Harold McClure ◽  
Amitinder Kaur
Keyword(s):  
T Lymphocytes ◽  
Immune Responses ◽  
Rhesus Macaques ◽  
Elispot Response ◽  
Cellular Immune Responses ◽  
Immunodeficiency Virus ◽  
Sooty Mangabeys ◽  
Siv Infection ◽  
Ifn Γ ◽  
Cellular Immune

ABSTRACT Sooty mangabeys are a natural host of simian immunodeficiency virus (SIV) that remain asymptomatic and do not exhibit increased immune activation or increased T-lymphocyte turnover despite sustained high levels of SIV viremia. In this study we asked whether an altered immune response to SIV contributes to the lack of immunopathology in sooty mangabeys as opposed to species with pathogenic lentivirus infection. SIV-specific cellular immune responses were investigated in a cohort of 25 sooty mangabeys with natural SIV infection. Gamma interferon (IFN-γ) enzyme-linked immunospot (ELISPOT) assay responses targeting a median of four SIV proteins were detected in all 25 mangabeys and were comparable in magnitude to those of 13 rhesus macaques infected with SIVmac251 for more than 6 months. As with rhesus macaques, Th2 ELISPOT responses to SIV were absent or >10-fold lower than the IFN-γ ELISPOT response to the same SIV protein. The SIV-specific ELISPOT response was predominantly mediated by CD8+ T lymphocytes; the frequency of circulating SIV-specific CD8+ T lymphocytes ranged between 0.11% and 3.26% in 13 mangabeys. Functionally, the SIV-specific CD8+ T lymphocytes were cytotoxic; secreted IFN-γ, tumor necrosis factor alpha, and macrophage inflammatory protein 1β; and had an activated effector phenotype. Although there was a trend toward higher frequencies of SIV-specific CD8+ T lymphocytes in mangabeys with lower viral loads, a significant inverse correlation between SIV viremia and SIV-specific cellular immunity was not detected. The consistent detection of Th1-type SIV-specific cellular immune responses in naturally infected sooty mangabeys suggests that immune attenuation is neither a feature of nor a requirement for maintenance of nonpathogenic SIV infection in its natural host.

scholarly journals Mobilization of tissue-resident memory CD4+ T lymphocytes and their contribution to a systemic secondary immune reaction

2020 ◽  
Author(s):  
Carla Cendón ◽  
Weijie Du ◽  
Pawel Durek ◽  
Tobias Alexander ◽  
Lindsay Serene ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Lymphocytes ◽  
Immune Responses ◽  
Immune Reaction ◽  
Memory T Cells ◽  
Time Window ◽  
Immune Memory ◽  
Resident Memory T Cells ◽  
Memory T Lymphocytes

AbstractWhile it is generally accepted that tissue-resident memory T lymphocytes protect host tissues from secondary immune challenges, it is unclear whether, and if so, how they contribute to systemic secondary immune responses. Here we show that in human individuals with an established immune memory to measles, mumps and rubella viruses, when challenged with the measles-mumps-rubella (MMR) vaccine again, tissue-resident memory CD4+ T cells are mobilized into the blood within 16 to 48 hours after vaccination. These cells then leave the blood again, and apparently contribute to the systemic secondary immune reaction, as is evident from the representation of mobilized T cell receptor Vβ clonotypes among newly generated circulating memory T lymphocytes, from day 7 onwards. Mobilization of the tissue-resident memory T cells is cognate, in that memory T lymphocytes recognizing other antigens, e.g. tetanus toxin, are not mobilized, unless they cross-react with the vaccine. These data originally demonstrate the essential contribution of tissue-resident memory T cells to secondary systemic immune responses, confirming that immunological memories to systemic pathogens are maintained (also) by tissue-resident memory T cells. In practical terms, the present work defines day 1 to 2 after antigenic challenge as a time window to assess the entire immunological T cell memory for a certain pathogen, including mobilized tissue-resident memory T cells, and its correlates of effectivity.Capsule summaryThe study demonstrates the rapid and cognate mobilization of tissue-resident memory CD4+ T cells into the blood upon antigenic rechallenge, and their contribution to secondary systemic immune responses.

scholarly journals The Effect of Antigen Dose and Antigen Presenting Process on T Cell Stimulation: A Method for Enrichment of TB10.4 Antigen-specific T-cell Clones

2021 ◽  
Author(s):  
Mahdieh Motiee ◽  
Ahmad Zavaran Hosseini ◽  
Sara Soudi ◽  
Seyed Mehdi Hassanzadeh
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Lymphocytes ◽  
Immune Responses ◽  
Interleukin 2 ◽  
Adoptive Cell Transfer ◽  
Adoptive T Cell Therapy ◽  
T Cell Therapy ◽  
Average Cell ◽  
Ifn Γ

T-lymphocytes have critical functions in the immune responses against viral and intracellular bacterial infections as well as cancers. Antigen (Ag)-specific T-lymphocyte clones enriched and expanded in vitro are valuable tools in the study of immune responses in animal models and adoptive T-cell therapy of patients with cancer or infection. We described a method for inducing, enriching, and replicating Ag-specific poly-clonal T-cells from BALB/c mice infected with live Bacillus Calmette Guérin (BCG) bacterium. During a 7-8 days procedure, T-lymphocytes were purified from immune cells of lymph nodes stimulated with immunodominant Ag of BCG, TB10.4, and expanded by interleukin -2 cytokine. We evaluated the effect of Ag doses (1, 10, and 100 µg/mL) and exposure method of Ag presenting cells (APCs) to T-cells, on T-cells’ proliferation, viability, and Interferon-gamma (IFN-γ) secretion at 2, 5, and 7 days after Ag stimulation. Increasing Ag concentration increased the average cell division, but at the highest dose of Ag (100 µg/mL), T-cell viability is decreased. Only clones induced by 10 µg/mL Ag produced a desirable amount of IFN-γ. Incubation of Ag and APCs, 24 h before T-lymphocytes addition, increased the proliferation and viability of cells. T cells are in a more favorable condition around day 5 of Ag stimulation in terms of proliferation and survival, and it is the desired time for T cell restimulation. For optimal preparation of specific T-cells for adoptive cell transfer, optimization of Ag dose, the order of APCs and T-cells exposure with Ag, and the duration of initial Ag stimulation, as well as the time for restimulation, is essential.

scholarly journals Thymic Independence of Adaptive Immunity to the Intracellular Pathogen Shigella flexneri Serotype 2a

1999 ◽  
Vol 67 (8) ◽  
pp. 3970-3979 ◽  
Author(s):  
Sing Sing Way ◽  
Alain C. Borczuk ◽  
Marcia B. Goldberg
Keyword(s):  
T Lymphocytes ◽  
Adaptive Immunity ◽  
Adoptive Transfer ◽  
B Lymphocyte ◽  
Shigella Flexneri ◽  
Intracellular Pathogen ◽  
Partial Protection ◽  
Cellular Immune Responses ◽  
Ifn Γ ◽  
Cellular Immune

ABSTRACT Shigella flexneri is a facultative intracellular pathogen. While immunity to several intracellular pathogens is mediated by T lymphocytes, it is unknown whether cellular immune responses are important to adaptive immunity to S. flexneri. We show that vaccination with S. flexneri serotype 2a confers protection to mice that lack T lymphocytes or gamma interferon (IFN-γ), specific depletion of T lymphocytes does not alter the protection, and adoptive transfer of splenocytes from vaccinated mice does not confer protection to naive mice. In contrast, vaccination conferred no protection to mice that lack B lymphocytes and adoptive transfer of immune sera conferred partial protection to naive mice. These data demonstrate that in the mouse bronchopulmonary model, adaptive immunity to S. flexneri 2a is an antibody-mediated, B-lymphocyte-dependent process and can be generated in the absence of T lymphocytes or IFN-γ.

scholarly journals Identification of Surrogates and Correlates of Protection in Protective Immunity againstMycobacterium bovisInfection Induced in Neonatal Calves by Vaccination withM. bovisBCG Pasteur andM. bovisBCG Danish

2011 ◽  
Vol 18 (3) ◽  
pp. 373-379 ◽  
Author(s):  
J. C. Hope ◽  
M. L. Thom ◽  
M. McAulay ◽  
E. Mead ◽  
H. M. Vordermeier ◽  
...  
Keyword(s):  
T Lymphocytes ◽  
Immune Responses ◽  
Protective Immunity ◽  
Protective Efficacy ◽  
Significant Degree ◽  
Degree Of Protection ◽  
Correlates Of Protection ◽  
Ifn Γ ◽  
Neonatal Calves ◽  
Protection Against Infection

ABSTRACTVaccination of neonatal calves withMycobacterium bovisbacillus Calmette-Guérin (BCG) induces a significant degree of protection against infection with virulentM. bovis, the causative agent of bovine tuberculosis (bTB). We compared two strains of BCG, Pasteur and Danish, in order to confirm that the current European human vaccine strain (BCG Danish) induced protective immunity in calves, and we assessed immune responses to determine correlates of protection that could assist future vaccine evaluation in cattle. Both vaccine strains induced antigen (purified protein derivate [PPD])-specific gamma interferon (IFN-γ) in whole-blood cultures. These responses were not significantly different for BCG Pasteur and BCG Danish and peaked at week 2 to 4 postvaccination. Vaccination with either BCG Danish or BCG Pasteur induced significant protection against bTB, with reductions in both lesion score and bacteriological burden evident in both groups of vaccinated calves compared with nonvaccinated control calves. Measurement of IFN-γ-expressing T lymphocytes postvaccination and postchallenge revealed both correlates and surrogates of protective efficacy. The frequency of central memory T lymphocytes present at 12 weeks postvaccination (at the time ofM. bovischallenge) correlated significantly with protection. Conversely, the number of IFN-γ-expressing effector T cells present afterM. bovischallenge was correlated with disease. These results demonstrate that vaccination of neonatal calves with either BCG Pasteur or BCG Danish induces protective immune responses against TB. In addition, we show that measurement of antigen-specific T lymphocyte populations may provide a reliable means for identifying protective vaccine candidates.

scholarly journals Cross-Protection against Challenge with Puumala Virus after Immunization with Nucleocapsid Proteins from Different Hantaviruses

2002 ◽  
Vol 76 (13) ◽  
pp. 6669-6677 ◽  
Author(s):  
Cristina de Carvalho Nicacio ◽  
Marcelo Gonzalez Della Valle ◽  
Paula Padula ◽  
Ewa Björling ◽  
Alexander Plyusnin ◽  
...  
Keyword(s):  
T Lymphocytes ◽  
Immune Responses ◽  
Hemorrhagic Fever ◽  
Cross Reactivity ◽  
Cross Protection ◽  
Laboratory Animals ◽  
Homologous Protein ◽  
Humoral Responses ◽  
Cellular Immune

ABSTRACT Hantaviruses are rodent-borne agents that cause hemorrhagic fever with renal syndrome or hantavirus pulmonary syndrome in humans. The nucleocapsid protein (N) is relatively conserved among hantaviruses and highly immunogenic in both laboratory animals and humans, and it has been shown to induce efficient protective immunity in animal models. To investigate the ability of recombinant N (rN) from different hantaviruses to elicit cross-protection, we immunized bank voles with rN from Puumala (PUUV), Topografov (TOPV), Andes (ANDV), and Dobrava (DOBV) viruses and subsequently challenged them with PUUV. All animals immunized with PUUV and TOPV rN were completely protected. In the group immunized with DOBV rN, 7 of 10 animals were protected, while only 3 of 8 animals were protected in the group immunized with ANDV rN, which is more closely related to PUUV rN than DOBV rN. Humoral and cellular immune responses after rN immunization were also investigated. The highest cross-reactive humoral responses against PUUV antigen were detected in sera from ANDV rN-immunized animals, followed by those from TOPV rN-immunized animals, and only very low antibody cross-reactivity was observed in sera from DOBV rN-immunized animals. In proliferation assays, T lymphocytes from animals immunized with all heterologous rNs were as efficiently recalled in vitro by PUUV rN as were T lymphocytes from animals immunized with homologous protein. In summary, this study has shown that hantavirus N can elicit cross-protective immune responses against PUUV, and the results suggest a more important role for the cellular arm of the immune response than for the humoral arm in cross-protection elicited by rN.

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