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1.
Int J Mol Sci ; 24(11)2023 Jun 05.
Article in English | MEDLINE | ID: covidwho-20242666

ABSTRACT

Waning vaccine-induced immunity, coupled with the emergence of SARS-CoV-2 variants, has inspired the widespread implementation of COVID-19 booster vaccinations. Here, we evaluated the potential of the GX-19N DNA vaccine as a heterologous booster to enhance the protective immune response to SARS-CoV-2 in mice primed with either an inactivated virus particle (VP) or an mRNA vaccine. We found that in the VP-primed condition, GX-19N enhanced the response of both vaccine-specific antibodies and cross-reactive T Cells to the SARS-CoV-2 variant of concern (VOC), compared to the homologous VP vaccine prime-boost. Under the mRNA-primed condition, GX-19N induced higher vaccine-induced T Cell responses but lower antibody responses than the homologous mRNA vaccine prime-boost. Furthermore, the heterologous GX-19N boost induced higher S-specific polyfunctional CD4+ and CD8+ T cell responses than the homologous VP or mRNA prime-boost vaccinations. Our results provide new insights into booster vaccination strategies for the management of novel COVID-19 variants.


Subject(s)
COVID-19 Vaccines , COVID-19 , T-Lymphocytes , Animals , Humans , Mice , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , DNA , RNA, Messenger/genetics , SARS-CoV-2 , Vaccination , Vaccines, Inactivated , Interferon-gamma/immunology , Interferon-gamma/metabolism
2.
Cytotherapy ; 25(3): 330-340, 2023 03.
Article in English | MEDLINE | ID: covidwho-2180302

ABSTRACT

BACKGROUND AIMS: We have previously demonstrated the safety and feasibility of adoptive cell therapy with CD45RA- memory T cells containing severe acute respiratory syndrome coronavirus 2-specific T cells for patients with coronavirus disease 2019 from an unvaccinated donor who was chosen based on human leukocyte antigen compatibility and cellular response. In this study, we examined the durability of cellular and humoral immunity within CD45RA- memory T cells and the effect of dexamethasone, the current standard of care treatment, and interleukin-15, a cytokine critically involved in T-cell maintenance and survival. METHODS: We performed a longitudinal analysis from previously severe acute respiratory syndrome coronavirus 2-infected and infection-naïve individuals covering 21 months from infection and 10 months after full vaccination with the BNT162b2 Pfizer/BioNTech vaccine. RESULTS: We observed that cellular responses are maintained over time. Humoral responses increased after vaccination but were gradually lost. In addition, dexamethasone did not alter cell functionality or proliferation of CD45RA- T cells, and interleukin-15 increased the memory T-cell activation state, regulatory T cell expression, and interferon gamma release. CONCLUSIONS: Our results suggest that the best donors for adoptive cell therapy would be recovered individuals and 2 months after vaccination, although further studies with larger cohorts would be needed to confirm this finding. Dexamethasone did not affect the characteristics of the memory T cells at a concentration used in the clinical practice and IL-15 showed a positive effect on SARS-CoV-2-specific CD45RA- T cells.


Subject(s)
COVID-19 , Interferon-gamma , Humans , Interferon-gamma/metabolism , Interleukin-15 , Memory T Cells , Donor Selection , BNT162 Vaccine , COVID-19/therapy , SARS-CoV-2 , COVID-19 Drug Treatment , Leukocyte Common Antigens/metabolism , Phenotype , Dexamethasone/pharmacology , Dexamethasone/therapeutic use , Cell Proliferation , Antibodies, Viral , Vaccination
3.
Front Immunol ; 13: 1031248, 2022.
Article in English | MEDLINE | ID: covidwho-2198876

ABSTRACT

Background: Limited data are available regarding the differences between immunological, biochemical, and cellular contents of human colostrum following maternal infection during pregnancy with coronavirus 2 disease (COVID-19). Objective: To investigate whether maternal COVID-19 infection may affect immunological, biochemical, and cellular contents of human colostrum. Methods: Using a case-control study design, we collected colostrum from 14 lactating women with a previous diagnosis of COVID-19 during pregnancy and 12 without a clear diagnosis during September 2020 to May 2021. Colostrum samples were analysed for some enzymes and non-enzymatic oxidative stress markers (SOD, CAT, GPx, MDA, GSH, GSSG, H2O2, MPO) and for IL-1ß, IL-6, tumour necrosis factor (TNF)-α, protein induced by interferon gamma (IP)-10, IL-8, IFN-λ1, IL12p70, IFN-α2, IFN-λ2/3, granulocyte macrophage colony stimulating factor (GM-CSF), IFN-ß, IL-10 and IFN-γ, along with IgA and IgG for the SARS-CoV-2 S protein. We perform immunophenotyping to assess the frequency of different cell types in the colostrum. Results: Colostrum from the COVID-19 symptomatic group in pregnancy contained reduced levels of H2O2, IFN-α2, and GM-CSF. This group had higher levels of GSH, and both NK cell subtypes CD3-CD56brightCD16-CD27+IFN-γ+ and CD3-CD56dimCD16+CD27- were also increased. Conclusion: The present results reinforce the protective role of colostrum even in the case of mild SARS-Cov-2 infection, in addition to demonstrating how adaptive the composition of colostrum is after infections. It also supports the recommendation to encourage lactating women to continue breastfeeding after COVID-19 illness.


Subject(s)
COVID-19 , Pregnancy Complications, Infectious , Pregnancy , Female , Humans , Cytokines/metabolism , Granulocyte-Macrophage Colony-Stimulating Factor/metabolism , Colostrum/metabolism , COVID-19/metabolism , Case-Control Studies , Hydrogen Peroxide/metabolism , Lactation , SARS-CoV-2 , Interferon-gamma/metabolism , Pregnancy Complications, Infectious/metabolism
4.
Emerg Microbes Infect ; 11(1): 2474-2484, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-2051171

ABSTRACT

BBIBP-CorV exerts efficient protection against SARS-CoV-2 infection. However, waning vaccine-induced humoral immune responses after two-dose vaccination have significantly undermined durable immuno-protection. In this study, we have demonstrated that although anti-spike (S) antibody responses in BBIBP-CorV vaccinees exhibited three serotypes after 6 months, including de novo sero-negative, sero-positive, and sero-decay features, S-specific interferon-γ release as well as Th1 cytokine production in CD4+ and CD8+ T cells were comparable, especially in vaccinees without detectable neutralizing antibodies. Notably, regardless of dramatic increases in humoral immunity after booster vaccination, T cell responses targeting S protein from either wild type or Omicron remained stable before and after booster vaccination in all three serotype vaccinees. No severe cases were observed even in the sero-decay group during the Omicron epidemic in Shanghai. Our results thus illustrate that unlike fluctuating humoral responses, viral-specific T cell responses are extremely stable after booster vaccination. Sustained T cell responses might be dedicated to the rapid restoration of antibody responses after booster vaccination.


Subject(s)
COVID-19 , Immunity, Humoral , Humans , Antibodies, Neutralizing/metabolism , Antibodies, Viral , CD8-Positive T-Lymphocytes , COVID-19/prevention & control , Interferon-gamma/metabolism , SARS-CoV-2 , Vaccination
5.
Emerg Microbes Infect ; 11(1): 2698-2710, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-2028964

ABSTRACT

The modulatory effect of C-Vx, a novel therapeutic agent, on the immune system of COVID-19 patients was investigated. The functions of T and NK cells of COVID-19 patients with different disease severity were evaluated by flow cytometry in response to C-Vx stimulation. The levels of pro- and anti-inflammatory cytokines were detected by multiplex assay in supernatants after cell culture with C-Vx. Bradykinin, IRF3, and IFN-α levels were also measured by ELISA in the presence or absence of C-Vx stimulation. As a result, increased CD107a expression was observed on NK cells in response to C-Vx addition. The proliferation of T cell subsets was increased by C-Vx, decreasing by disease severity. IL-4 and IL-10 levels were elevated while IFN-γ and IL-17 levels were reduced in T cells following C-Vx stimulation. However, the levels of pro-inflammatory IL-1ß, IL-6, IL-8, IFN-γ and GM-CSF were significantly increased upon C-Vx stimulation. IFN-α levels tended to increase after incubation with C-Vx. These findings support an immunomodulatory action of C-Vx on the immune system of patients with a mild and moderate phase of COVID-19.


Subject(s)
COVID-19 , Humans , Cytokines , Interferon-gamma/metabolism , T-Lymphocytes , Killer Cells, Natural
6.
J Exp Med ; 219(2)2022 02 07.
Article in English | MEDLINE | ID: covidwho-1984990

ABSTRACT

In rare instances, pediatric SARS-CoV-2 infection results in a novel immunodysregulation syndrome termed multisystem inflammatory syndrome in children (MIS-C). We compared MIS-C immunopathology with severe COVID-19 in adults. MIS-C does not result in pneumocyte damage but is associated with vascular endotheliitis and gastrointestinal epithelial injury. In MIS-C, the cytokine release syndrome is characterized by IFNγ and not type I interferon. Persistence of patrolling monocytes differentiates MIS-C from severe COVID-19, which is dominated by HLA-DRlo classical monocytes. IFNγ levels correlate with granzyme B production in CD16+ NK cells and TIM3 expression on CD38+/HLA-DR+ T cells. Single-cell TCR profiling reveals a skewed TCRß repertoire enriched for TRBV11-2 and a superantigenic signature in TIM3+/CD38+/HLA-DR+ T cells. Using NicheNet, we confirm IFNγ as a central cytokine in the communication between TIM3+/CD38+/HLA-DR+ T cells, CD16+ NK cells, and patrolling monocytes. Normalization of IFNγ, loss of TIM3, quiescence of CD16+ NK cells, and contraction of patrolling monocytes upon clinical resolution highlight their potential role in MIS-C immunopathogenesis.


Subject(s)
COVID-19/complications , Hepatitis A Virus Cellular Receptor 2/metabolism , Interferon-gamma/metabolism , Killer Cells, Natural/immunology , Monocytes/metabolism , Receptors, IgG/metabolism , Systemic Inflammatory Response Syndrome/immunology , T-Lymphocytes/immunology , Adolescent , Alveolar Epithelial Cells/pathology , B-Lymphocytes/immunology , Blood Vessels/pathology , COVID-19/immunology , COVID-19/pathology , Cell Proliferation , Child , Cohort Studies , Complement Activation , Cytokines/metabolism , Enterocytes/pathology , Female , Humans , Immunity, Humoral , Inflammation/pathology , Interferon Type I/metabolism , Interleukin-15/metabolism , Lymphocyte Activation/immunology , Male , Receptors, Antigen, T-Cell/metabolism , SARS-CoV-2/immunology , Superantigens/metabolism , Systemic Inflammatory Response Syndrome/pathology
7.
Int J Mol Sci ; 23(14)2022 Jul 20.
Article in English | MEDLINE | ID: covidwho-1938841

ABSTRACT

Specific T cells are crucial to control SARS-CoV-2 infection, avoid reinfection and confer protection after vaccination. We have studied patients with severe or moderate COVID-19 pneumonia, compared to patients who recovered from a severe or moderate infection that had occurred about 4 months before the analyses. In all these subjects, we assessed the polyfunctionality of virus-specific CD4+ and CD8+ T cells by quantifying cytokine production after in vitro stimulation with different SARS-CoV-2 peptide pools covering different proteins (M, N and S). In particular, we quantified the percentage of CD4+ and CD8+ T cells simultaneously producing interferon-γ, tumor necrosis factor, interleukin (IL)-2, IL-17, granzyme B, and expressing CD107a. Recovered patients who experienced a severe disease display high proportions of antigen-specific CD4+ T cells producing Th1 and Th17 cytokines and are characterized by polyfunctional SARS-CoV-2-specific CD4+ T cells. A similar profile was found in patients experiencing a moderate form of COVID-19 pneumonia. No main differences in polyfunctionality were observed among the CD8+ T cell compartments, even if the proportion of responding cells was higher during the infection. The identification of those functional cell subsets that might influence protection can thus help in better understanding the complexity of immune response to SARS-CoV-2.


Subject(s)
COVID-19 , CD4-Positive T-Lymphocytes , CD8-Positive T-Lymphocytes , Humans , Interferon-gamma/metabolism , SARS-CoV-2
8.
J Endocrinol Invest ; 45(11): 2157-2163, 2022 Nov.
Article in English | MEDLINE | ID: covidwho-1930622

ABSTRACT

BACKGROUND: A more severe course of COVID-19 was associated with low levels of Vitamin D (VitD). Moreover in vitro data showed that VitD up-regulates the mRNA of the Angiotensin Converting Enzyme 2 (ACE-2), the SARS-COV-2 receptor in different type of cells. ACE-2 is expressed in several type of tissues including thyroid cells, on which its mRNA was shown to be up-regulated by interferon-gamma (IFN-γ). The aim of the present study was to investigate if treatment with VitD alone or in combination with IFN-γ would increase ACE-2 both at mRNA and protein levels in primary cultures of human thyrocytes. MATERIALS AND METHODS: Primary thyroid cell cultures were treated with VitD and IFN-γ alone or in combination for 24 h. ACE-2 mRNA levels were measured by Real-time Polymerase Chain Reaction (RT-PCR). The presence of ACE-2 on thyroid cell membrane was assessed by immunocytochemistry basally and after the previous mentioned treatments. RESULTS: ACE-2 mRNA levels increased after treatment with VitD and IFN-γ alone. The combination treatment (VitD + IFN-γ) showed an additive increase of ACE-2-mRNA. Immunocytochemistry experiments showed ACE-2 protein on thyroid cells membrane. ACE-2 expression increased after treatment with VitD and IFN-γ alone and further increased by the combination treatment with VitD + IFN-γ. CONCLUSIONS: VitD would defend the body by SARS-COV2 both by regulating the host immune defense and by up-regulating of the expression of the ACE-2 receptor. The existence of a co-operation between VitD and IFN-γ demonstrated in other systems is supported also for ACE-2 up-regulation. These observations lead to an increased interest for the potential therapeutic benefits of VitD supplementation in COVID-19.


Subject(s)
Angiotensin-Converting Enzyme 2 , COVID-19 Drug Treatment , Humans , Interferon-gamma/metabolism , Interferon-gamma/pharmacology , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Viral , SARS-CoV-2 , Thyroid Gland/metabolism , Vitamin D/metabolism , Vitamin D/pharmacology , Vitamins/metabolism
9.
Int J Mol Sci ; 23(12)2022 Jun 13.
Article in English | MEDLINE | ID: covidwho-1896884

ABSTRACT

NK degranulation plays an important role in the cytotoxic activity of innate immunity in the clearance of intracellular infections and is an important factor in the outcome of the disease. This work has studied NK degranulation and innate immunological profiles and functionalities in COVID-19 patients and its association with the severity of the disease. A prospective observational study with 99 COVID-19 patients was conducted. Patients were grouped according to hospital requirements and severity. Innate immune cell subpopulations and functionalities were analyzed. The profile and functionality of innate immune cells differ between healthy controls and severe patients; CD56dim NK cells increased and MAIT cells and NK degranulation rates decreased in the COVID-19 subjects. Higher degranulation rates were observed in the non-severe patients and in the healthy controls compared to the severe patients. Benign forms of the disease had a higher granzymeA/granzymeB ratio than complex forms. In a multivariate analysis, the degranulation capacity resulted in a protective factor against severe forms of the disease (OR: 0.86), whereas the permanent expression of NKG2D in NKT cells was an independent risk factor (OR: 3.81; AUC: 0.84). In conclusion, a prompt and efficient degranulation functionality in the early stages of infection could be used as a tool to identify patients who will have a better evolution.


Subject(s)
COVID-19 , Natural Killer T-Cells , Cell Degranulation , Humans , Interferon-gamma/metabolism , Killer Cells, Natural , Lymphocyte Activation
10.
J Med Chem ; 65(3): 2558-2570, 2022 02 10.
Article in English | MEDLINE | ID: covidwho-1895561

ABSTRACT

Safe and effective vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its variants are the best approach to successfully combat the COVID-19 pandemic. The receptor-binding domain (RBD) of the viral spike protein is a major target to develop candidate vaccines. α-Galactosylceramide (αGalCer), a potent invariant natural killer T cell (iNKT) agonist, was site-specifically conjugated to the N-terminus of the RBD to form an adjuvant-protein conjugate, which was anchored on the liposome surface. This is the first time that an iNKT cell agonist was conjugated to the protein antigen. Compared to the unconjugated RBD/αGalCer mixture, the αGalCer-RBD conjugate induced significantly stronger humoral and cellular responses. The conjugate vaccine also showed effective cross-neutralization to all variants of concern (B.1.1.7/alpha, B.1.351/beta, P.1/gamma, B.1.617.2/delta, and B.1.1.529/omicron). These results suggest that the self-adjuvanting αGalCer-RBD has great potential to be an effective COVID-19 vaccine candidate, and this strategy might be useful for designing various subunit vaccines.


Subject(s)
COVID-19 Vaccines/therapeutic use , COVID-19/therapy , Galactosylceramides/therapeutic use , Peptide Fragments/therapeutic use , SARS-CoV-2/immunology , Vaccines, Conjugate/therapeutic use , Adjuvants, Immunologic/chemistry , Adjuvants, Immunologic/therapeutic use , Animals , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19 Vaccines/chemistry , COVID-19 Vaccines/immunology , Female , Galactosylceramides/chemistry , Galactosylceramides/immunology , Immunity, Humoral/drug effects , Immunity, Innate/drug effects , Interferon-gamma/metabolism , Liposomes/chemistry , Liposomes/immunology , Liposomes/therapeutic use , Mice, Inbred BALB C , Peptide Fragments/chemistry , Peptide Fragments/immunology , Protein Domains , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/therapeutic use , Vaccines, Conjugate/chemistry , Vaccines, Conjugate/immunology
11.
J Virol ; 96(13): e0050922, 2022 07 13.
Article in English | MEDLINE | ID: covidwho-1891737

ABSTRACT

Cell-mediated immunity is critical for long-term protection against most viral infections, including coronaviruses. We studied 23 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected survivors over a 1-year post-symptom onset (PSO) interval by ex vivo cytokine enzyme-linked immunosorbent spot assay (ELISpot) assay. All subjects demonstrated SARS-CoV-2-specific gamma interferon (IFN-γ), interleukin 2 (IL-2), and granzyme B (GzmB) T cell responses at presentation, with greater frequencies in severe disease. Cytokines, mainly produced by CD4+ T cells, targeted all structural proteins (nucleocapsid, membrane, and spike) except envelope, with GzmB and IL-2 greater than IFN-γ. Mathematical modeling predicted that (i) cytokine responses peaked at 6 days for IFN-γ, 36 days for IL-2, and 7 days for GzmB, (ii) severe illness was associated with reduced IFN-γ and GzmB but increased IL-2 production rates, and (iii) males displayed greater production of IFN-γ, whereas females produced more GzmB. Ex vivo responses declined over time, with persistence of IL-2 in 86% and of IFN-γ and GzmB in 70% of subjects at a median of 336 days PSO. The average half-life of SARS-CoV-2-specific cytokine-producing cells was modeled to be 139 days (~4.6 months). Potent T cell proliferative responses persisted throughout observation, were CD4 dominant, and were capable of producing all 3 cytokines. Several immunodominant CD4 and CD8 epitopes identified in this study were shared by seasonal coronaviruses or SARS-CoV-1 in the nucleocapsid and membrane regions. Both SARS-CoV-2-specific CD4+ and CD8+ T cell clones were able to kill target cells, though CD8 tended to be more potent. IMPORTANCE Our findings highlight the relative importance of SARS-CoV-2-specific GzmB-producing T cell responses in SARS-CoV-2 control and shared CD4 and CD8 immunodominant epitopes in seasonal coronaviruses or SARS-CoV-1, and they indicate robust persistence of T cell memory at least 1 year after infection. Our findings should inform future strategies to induce T cell vaccines against SARS-CoV-2 and other coronaviruses.


Subject(s)
COVID-19 , Cytokines , Immunity , SARS-CoV-2 , CD4-Positive T-Lymphocytes , CD8-Positive T-Lymphocytes , COVID-19/immunology , COVID-19 Vaccines , Cytokines/immunology , Female , Humans , Immunologic Memory , Interferon-gamma/metabolism , Interleukin-2/immunology , Male , Severity of Illness Index , Time Factors
12.
Arch Virol ; 166(8): 2285-2289, 2021 Aug.
Article in English | MEDLINE | ID: covidwho-1826502

ABSTRACT

Mesenchymal stromal cells (MSCs) are considered multipotent progenitors with the capacity to differentiate into mesoderm-like cells in many species. The immunosuppressive properties of MSCs are important for downregulating inflammatory responses. Turkey coronavirus (TCoV) is the etiological agent of a poult mortality syndrome that affects intestinal epithelial cells. In this study, poult MSCs were isolated, characterized, and infected with TCoV after in vitro culture. The poult-derived MSCs showed fibroblast-like morphology and the ability to undergo differentiation into mesodermal-derived cells and to support virus replication. Infection with TCoV resulted in cytopathic effects and the loss of cell viability. TCoV antigens and new viral progeny were detected at high levels, as were transcripts of the pro-inflammatory factors INFγ, IL-6, and IL-8. These findings suggest that the cytokine storm phenomenon is not restricted to one genus of the family Coronaviridae and that MSCs cannot always balance the process.


Subject(s)
Coronavirus, Turkey/physiology , Cytokines/metabolism , Virus Replication , Animals , Cell Differentiation , Cell Survival , Cytopathogenic Effect, Viral , Interferon-gamma/metabolism , Interleukin-6/metabolism , Interleukin-8/metabolism , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/metabolism , Mesenchymal Stem Cells/virology , Turkeys , Up-Regulation
13.
Immunity ; 55(3): 382-384, 2022 03 08.
Article in English | MEDLINE | ID: covidwho-1747889

ABSTRACT

Macrophage activation is essential for effective immunity to infection but can also contribute to disease through incompletely understood mechanisms. In this issue of Immunity, Simpson et al. reveal that death of activated macrophages integrates extrinsic and intrinsic pathways of apoptosis that contribute to damaging host responses.


Subject(s)
Interferon-gamma , Macrophage Activation , Apoptosis , Caspase 8/metabolism , Cell Death , Interferon-gamma/metabolism , Ligands , Macrophages/immunology
14.
Cells ; 11(3)2022 02 06.
Article in English | MEDLINE | ID: covidwho-1686620

ABSTRACT

Necroptosis, a form of programmed lytic cell death, has emerged as a driving factor in the pathogenesis of acute lung injury (ALI). As ALI is often associated with a cytokine storm, we determined whether pro-inflammatory cytokines modulate the susceptibility of lung cells to necroptosis and which mediators dominate to control necroptosis. In this study, we pretreated/primed mouse primary lung epithelial and endothelial cells with various inflammatory mediators and assessed cell type-dependent responses to different necroptosis inducers and their underlying mechanisms. We found that interferon-γ (IFNγ) as low as 1 ng/mL preferentially promoted necroptosis and accelerated the release of damage-associated molecular patterns from primary alveolar and airway epithelial cells but not lung microvascular endothelial cells. Type-I IFNα was about fifty-fold less effective than IFNγ. Conversely, TNFα or agonists of Toll-like receptor-3 (TLR3), TLR4, TLR7 and TLR9 had a minor effect. The enhanced necroptosis in IFNγ-activated lung epithelial cells was dependent on IFNγ signaling and receptor-interacting protein kinase-3. We further showed that necroptosis effector mixed lineage kinase domain-like protein (MLKL) was predominantly induced by IFNγ, contributing to the enhanced necroptosis in lung epithelial cells. Collectively, our findings indicate that IFNγ is a potent enhancer of lung epithelial cell susceptibility to necroptosis.


Subject(s)
Interferon-gamma , Necroptosis , Animals , Endothelial Cells/metabolism , Epithelial Cells/metabolism , Interferon-gamma/metabolism , Interferon-gamma/pharmacology , Lung/pathology , Mice , Protein Kinases/metabolism
15.
Sci Rep ; 12(1): 1727, 2022 02 02.
Article in English | MEDLINE | ID: covidwho-1671625

ABSTRACT

As the first dose of Gam-COVID-Vac, is currently used as a single dose vaccine in some countries, we investigated the immunogenicity of this at 4 weeks (327 naïve individuals). 88.7% seroconverted, with significantly lower seroconversion rates in those over 60 years (p = 0.004) and significantly lower than previously seen with AZD1222 (p = 0.018). 82.6% developed ACE2 receptor blocking antibodies, although levels were significantly lower than following natural infection (p = 0.0009) and a single dose of AZD1222 (p < 0.0001). Similar titres of antibodies were observed to the receptor binding domain of WT, B.1.1.7 and B.1.617.2 compared to AZD1222, while the levels for B.1.351 were significantly higher (p = 0.006) for Gam-COVID-Vac. 30% developed ex vivo IFNγ ELISpot responses (significantly lower than AZD1222), and high frequency of CD107a expressing T cells along with memory B cell responses. Although single dose of Gam-COVID-Vac was highly immunogenic, administration of a second dose is likely to be beneficial.


Subject(s)
Antibodies, Neutralizing/blood , Antibodies, Viral/blood , COVID-19 Vaccines/administration & dosage , COVID-19/prevention & control , ChAdOx1 nCoV-19/administration & dosage , Immunization , Immunogenicity, Vaccine , SARS-CoV-2/immunology , Vaccines, Synthetic/administration & dosage , Adult , Aged , Aged, 80 and over , Angiotensin-Converting Enzyme 2/immunology , Biomarkers/blood , COVID-19/immunology , COVID-19/virology , COVID-19 Vaccines/immunology , ChAdOx1 nCoV-19/immunology , Female , Humans , Interferon-gamma/metabolism , Lymphocytes/immunology , Lymphocytes/metabolism , Lymphocytes/virology , Male , Middle Aged , Seroconversion , Time Factors , Treatment Outcome , Vaccines, Synthetic/immunology , Young Adult
16.
Nat Immunol ; 23(3): 380-385, 2022 03.
Article in English | MEDLINE | ID: covidwho-1671602

ABSTRACT

Delayed dosing intervals are a strategy to immunize a greater proportion of the population. In an observational study, we compared humoral and cellular responses in health care workers receiving two doses of BNT162b2 (Pfizer-BioNTech) vaccine at standard (3- to 6-week) and delayed (8- to 16-week) intervals. In the delayed-interval group, anti-receptor-binding domain antibody titers were significantly enhanced compared to the standard-interval group. The 50% plaque reduction neutralization test (PRNT50) and PRNT90 titers against wild-type (ancestral) severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and Alpha, Beta and Delta variants were higher in the delayed-interval group. Spike-specific polyfunctional CD4+ and CD8+ T cells expressing interferon-γ and interleukin-2 were comparable between the two groups. Here, we show that the strategy of delaying second doses of mRNA vaccination may lead to enhanced humoral immune responses, including improved virus neutralization against wild-type and variant SARS-CoV-2 viruses. This finding has potentially important implications as vaccine implementation continues across a greater proportion of the global population.


Subject(s)
BNT162 Vaccine/immunology , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , COVID-19/immunology , SARS-CoV-2/physiology , Adult , Cells, Cultured , Female , Humans , Immunity, Humoral , Immunization, Secondary , Interferon-gamma/metabolism , Interleukin-2/metabolism , Male , Middle Aged , Vaccination , Vaccination Hesitancy
17.
Viruses ; 14(1)2022 01 12.
Article in English | MEDLINE | ID: covidwho-1631201

ABSTRACT

γδ T cells are innate cells able to quickly eliminate pathogens or infected/tumoral cells by their antiviral and adjuvancy activities. The role of γδ T cells during Dengue Viral Infection (DENV) infection is not fully elucidated. Nevertheless, human primary γδ T cells have been shown to kill in vitro DENV-infected cells, thus highlighting their possible antiviral function. The aim of this work was to characterize the phenotype and function of Vδ2 T cells in DENV patients. Fifteen DENV patients were enrolled for this study and peripheral blood mononuclear cells (PBMC) were used to analyze Vδ2-T-cell frequency, differentiation profile, activation/exhaustion status, and functionality by multiparametric flow cytometry. Our data demonstrated that DENV infection was able to significantly reduce Vδ2-T-cell frequency and to increase their activation (CD38 and HLA-DR) and exhaustion markers (PD-1 and TIM-3). Furthermore, Vδ2 T cells showed a reduced capability to produce IFN-γ after phosphoantigenic stimulation that can be associated to TIM-3 expression. Several studies are needed to depict the possible clinical impact of γδ-T-cell impairment on disease severity and to define the antiviral and immunoregulatory activities of γδ T cells in the first phases of infection.


Subject(s)
Dengue/immunology , Hepatitis A Virus Cellular Receptor 2/metabolism , Interferon-gamma/metabolism , Intraepithelial Lymphocytes/immunology , Adaptation, Physiological , Adult , Flow Cytometry , Hepatitis A Virus Cellular Receptor 2/genetics , Humans , Immunity, Innate , Leukocytes, Mononuclear/immunology , Lymphocyte Activation/immunology , Male , Middle Aged , T-Lymphocyte Subsets/immunology
18.
Elife ; 112022 01 13.
Article in English | MEDLINE | ID: covidwho-1622818

ABSTRACT

Despite tremendous progress in the understanding of COVID-19, mechanistic insight into immunological, disease-driving factors remains limited. We generated maVie16, a mouse-adapted SARS-CoV-2, by serial passaging of a human isolate. In silico modeling revealed how only three Spike mutations of maVie16 enhanced interaction with murine ACE2. maVie16 induced profound pathology in BALB/c and C57BL/6 mice, and the resulting mouse COVID-19 (mCOVID-19) replicated critical aspects of human disease, including early lymphopenia, pulmonary immune cell infiltration, pneumonia, and specific adaptive immunity. Inhibition of the proinflammatory cytokines IFNγ and TNF substantially reduced immunopathology. Importantly, genetic ACE2-deficiency completely prevented mCOVID-19 development. Finally, inhalation therapy with recombinant ACE2 fully protected mice from mCOVID-19, revealing a novel and efficient treatment. Thus, we here present maVie16 as a new tool to model COVID-19 for the discovery of new therapies and show that disease severity is determined by cytokine-driven immunopathology and critically dependent on ACE2 in vivo.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , COVID-19/virology , Interferon-gamma/pharmacology , SARS-CoV-2/pathogenicity , Adaptive Immunity/immunology , Animals , Disease Models, Animal , Interferon-gamma/metabolism , Mice, Inbred BALB C , Mice, Inbred C57BL , Peptidyl-Dipeptidase A/genetics , Spike Glycoprotein, Coronavirus/genetics
19.
EBioMedicine ; 73: 103679, 2021 Nov.
Article in English | MEDLINE | ID: covidwho-1595805

ABSTRACT

BACKGROUND: The immunogenicity of a two-dose mRNA COVID-19 vaccine regimen is low in kidney transplant (KT) recipients. Here, we provide a thorough assessment of the immunogenicity of a three-dose COVID-19 vaccine regimen in this population. METHODS: We performed a prospective longitudinal study in sixty-one KT recipients given three doses of the BNT162b2 COVID-19 vaccine. We performed semi-structured pharmacovigilance interviews and monitored donor-specific antibodies and kidney function. We compared levels of anti-spike IgG, pseudo-neutralization activity against vaccine homologous and heterologous variants, frequency of spike-specific interferon (IFN)-γ-secreting cells, and antigen-induced cytokine production 28 days after the second and third doses. FINDINGS: Reactions to vaccine were mild. One patient developed donor-specific anti-HLA antibodies after the second dose which could be explained by non-adherence to immunosuppressive therapy. Spike-specific IgG seroconversion raised from 44·3% (n=27) after the second dose to 62·3% (n=38) after the third dose (p<0·05). The mean level of spike-specific IgG increased from 1620 (SD, 3460) to 8772 (SD, 16733) AU/ml (p<0·0001). Serum neutralizing activity increased after the third dose for all variants of concern tested including the Delta variant (p<0·0001). The frequency of spike-specific IFN-γ-secreting cells increased from 19·9 (SD, 56·0) to 64·0 (SD, 76·8) cells/million PBMCs after the third dose (p<0·0001). A significant increase in IFN-γ responses was also observed in patients who remained seronegative after three doses (p<0·0001). INTERPRETATION: A third dose of the BNT162b2 vaccine increases both cross-variant neutralizing antibody and cellular responses in KT recipients with an acceptable tolerability profile. FUNDING: Nice University Hospital, University Cote d'Azur.


Subject(s)
Antibodies, Neutralizing/immunology , BNT162 Vaccine/immunology , COVID-19/immunology , Kidney Transplantation , Aged , Antibodies, Neutralizing/blood , Autoantibodies/blood , BNT162 Vaccine/administration & dosage , BNT162 Vaccine/adverse effects , COVID-19/prevention & control , COVID-19/virology , Female , Graft Rejection/prevention & control , HLA Antigens/immunology , Humans , Immunoglobulin G/blood , Immunoglobulin G/immunology , Immunosuppressive Agents/therapeutic use , Interferon-gamma/metabolism , Leukocytes, Mononuclear/cytology , Leukocytes, Mononuclear/metabolism , Longitudinal Studies , Male , Middle Aged , Risk Factors , SARS-CoV-2/immunology , SARS-CoV-2/isolation & purification , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/immunology
20.
Lancet Oncol ; 22(12): 1681-1691, 2021 12.
Article in English | MEDLINE | ID: covidwho-1586209

ABSTRACT

BACKGROUND: Patients with cancer have an increased risk of complications from SARS-CoV-2 infection. Vaccination to prevent COVID-19 is recommended, but data on the immunogenicity and safety of COVID-19 vaccines for patients with solid tumours receiving systemic cancer treatment are scarce. Therefore, we aimed to assess the impact of immunotherapy, chemotherapy, and chemoimmunotherapy on the immunogenicity and safety of the mRNA-1273 (Moderna Biotech, Madrid, Spain) COVID-19 vaccine as part of the Vaccination Against COVID in Cancer (VOICE) trial. METHODS: This prospective, multicentre, non-inferiority trial was done across three centres in the Netherlands. Individuals aged 18 years or older with a life expectancy of more than 12 months were enrolled into four cohorts: individuals without cancer (cohort A [control cohort]), and patients with solid tumours, regardless of stage and histology, treated with immunotherapy (cohort B), chemotherapy (cohort C), or chemoimmunotherapy (cohort D). Participants received two mRNA-1273 vaccinations of 100 µg in 0·5 mL intramuscularly, 28 days apart. The primary endpoint, analysed per protocol (excluding patients with a positive baseline sample [>10 binding antibody units (BAU)/mL], indicating previous SARS-CoV-2 infection), was defined as the SARS-CoV-2 spike S1-specific IgG serum antibody response (ie, SARS-CoV-2-binding antibody concentration of >10 BAU/mL) 28 days after the second vaccination. For the primary endpoint analysis, a non-inferiority design with a margin of 10% was used. We also assessed adverse events in all patients who received at least one vaccination, and recorded solicited adverse events in participants who received at least one vaccination but excluding those who already had seroconversion (>10 BAU/mL) at baseline. This study is ongoing and is registered with ClinicalTrials.gov, NCT04715438. FINDINGS: Between Feb 17 and March 12, 2021, 791 participants were enrolled and followed up for a median of 122 days (IQR 118 to 128). A SARS-CoV-2-binding antibody response was found in 240 (100%; 95% CI 98 to 100) of 240 evaluable participants in cohort A, 130 (99%; 96 to >99) of 131 evaluable patients in cohort B, 223 (97%; 94 to 99) of 229 evaluable patients in cohort C, and 143 (100%; 97 to 100) of 143 evaluable patients in cohort D. The SARS-CoV-2-binding antibody response in each patient cohort was non-inferior compared with cohort A. No new safety signals were observed. Grade 3 or worse serious adverse events occurred in no participants in cohort A, three (2%) of 137 patients in cohort B, six (2%) of 244 patients in cohort C, and one (1%) of 163 patients in cohort D, with four events (two of fever, and one each of diarrhoea and febrile neutropenia) potentially related to the vaccination. There were no vaccine-related deaths. INTERPRETATION: Most patients with cancer develop, while receiving chemotherapy, immunotherapy, or both for a solid tumour, an adequate antibody response to vaccination with the mRNA-1273 COVID-19 vaccine. The vaccine is also safe in these patients. The minority of patients with an inadequate response after two vaccinations might benefit from a third vaccination. FUNDING: ZonMw, The Netherlands Organisation for Health Research and Development.


Subject(s)
2019-nCoV Vaccine mRNA-1273/adverse effects , 2019-nCoV Vaccine mRNA-1273/immunology , Antineoplastic Agents/immunology , Immunotherapy , Neoplasms/therapy , Vaccination/adverse effects , 2019-nCoV Vaccine mRNA-1273/administration & dosage , Aged , Antibodies, Viral/blood , Antineoplastic Agents/therapeutic use , COVID-19/prevention & control , Cohort Studies , Combined Modality Therapy , Female , Humans , Immunogenicity, Vaccine , Immunomodulation , Injections, Intramuscular , Interferon-gamma/metabolism , Male , Middle Aged , Neoplasms/immunology , Netherlands , Prospective Studies , SARS-CoV-2/immunology , Surveys and Questionnaires
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