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2.
Nat Immunol ; 24(6): 966-978, 2023 06.
Article in English | MEDLINE | ID: covidwho-20245297

ABSTRACT

High-risk groups, including Indigenous people, are at risk of severe COVID-19. Here we found that Australian First Nations peoples elicit effective immune responses to COVID-19 BNT162b2 vaccination, including neutralizing antibodies, receptor-binding domain (RBD) antibodies, SARS-CoV-2 spike-specific B cells, and CD4+ and CD8+ T cells. In First Nations participants, RBD IgG antibody titers were correlated with body mass index and negatively correlated with age. Reduced RBD antibodies, spike-specific B cells and follicular helper T cells were found in vaccinated participants with chronic conditions (diabetes, renal disease) and were strongly associated with altered glycosylation of IgG and increased interleukin-18 levels in the plasma. These immune perturbations were also found in non-Indigenous people with comorbidities, indicating that they were related to comorbidities rather than ethnicity. However, our study is of a great importance to First Nations peoples who have disproportionate rates of chronic comorbidities and provides evidence of robust immune responses after COVID-19 vaccination in Indigenous people.


Subject(s)
COVID-19 Vaccines , COVID-19 , Humans , BNT162 Vaccine , COVID-19/prevention & control , CD8-Positive T-Lymphocytes , Australia/epidemiology , SARS-CoV-2 , Immunoglobulin G , Antibodies, Neutralizing , Immunity , Antibodies, Viral , Vaccination
3.
Nat Rev Immunol ; 23(6): 381-396, 2023 06.
Article in English | MEDLINE | ID: covidwho-20245248

ABSTRACT

Neutralizing antibodies are known to have a crucial role in protecting against SARS-CoV-2 infection and have been suggested to be a useful correlate of protection for vaccine clinical trials and for population-level surveys. In addition to neutralizing virus directly, antibodies can also engage immune effectors through their Fc domains, including Fc receptor-expressing immune cells and complement. The outcome of these interactions depends on a range of factors, including antibody isotype-Fc receptor combinations, Fc receptor-bearing cell types and antibody post-translational modifications. A growing body of evidence has shown roles for these Fc-dependent antibody effector functions in determining the outcome of SARS-CoV-2 infection. However, measuring these functions is more complicated than assays that measure antibody binding and virus neutralization. Here, we examine recent data illuminating the roles of Fc-dependent antibody effector functions in the context of SARS-CoV-2 infection, and we discuss the implications of these data for the development of next-generation SARS-CoV-2 vaccines and therapeutics.


Subject(s)
COVID-19 , Humans , COVID-19 Vaccines , Antibodies, Viral , SARS-CoV-2 , Antibodies, Neutralizing , Immunoglobulin Fc Fragments , Receptors, Fc
4.
Sci Rep ; 13(1): 9264, 2023 06 07.
Article in English | MEDLINE | ID: covidwho-20245092

ABSTRACT

The objective of this study was to clarify the impact of adverse reactions on immune dynamics. We investigated the pattern of systemic adverse reactions after the second and third coronavirus disease 2019 (COVID-19) vaccinations and their relationship with immunoglobulin G against severe acute respiratory syndrome coronavirus 2 spike 1 protein titers, neutralizing antibody levels, peak cellular responses, and the rate of decrease after the third vaccination in a large-scale community-based cohort in Japan. Participants who received a third vaccination with BNT162b2 (Pfizer/BioNTech) or mRNA-1273 (Moderna), had two blood samples, had not had COVID-19, and had information on adverse reactions after the second and third vaccinations (n = 2198) were enrolled. We collected data on sex, age, adverse reactions, comorbidities, and daily medicine using a questionnaire survey. Participants with many systemic adverse reactions after the second and third vaccinations had significantly higher humoral and cellular immunity in the peak phase. Participants with multiple systemic adverse reactions after the third vaccination had small changes in the geometric values of humoral immunity and had the largest geometric mean of cellar immunity in the decay phase. Systemic adverse reactions after the third vaccination helped achieve high peak values and maintain humoral and cellular immunity. This information may help promote uptake of a third vaccination, even among those who hesitate due to adverse reactions.


Subject(s)
BNT162 Vaccine , COVID-19 , Humans , Antibodies, Viral , BNT162 Vaccine/adverse effects , Complementary Therapies , COVID-19/prevention & control , Immunity, Cellular , Immunity, Humoral , Vaccination/adverse effects
5.
Medicine (Baltimore) ; 102(20): e33824, 2023 May 19.
Article in English | MEDLINE | ID: covidwho-20245062

ABSTRACT

To search whether or not the severe acute respiratory syndrome corona virus-2 (SARS-CoV-2) messenger ribonucleic acid (mRNA) vaccine affects the fertility of women at the 6th months by using AMH, which is an ovarian reserve test. Our study, designed as a prospective case-control study, included 104 women who presented to the GOP EAH obstetrics and gynecology outpatient clinic in January and February 2022. The study group included 74 women who presented to the outpatient clinic and planned to be vaccinated and 30 women who refused to be vaccinated as the control group. Anti-COVID-19 antibody levels in all participants were checked before participation in the study, and participants who were positive were excluded from the study. Blood was taken from the participants in both control and study groups to evaluate their AMH levels before the 2 doses of vaccination. After 2 doses of the vaccine, they were called for follow-up, and serological tests were performed to check whether they were positive for anti-COVID-19 antibodies. Participants in both groups were referred for follow-up after 6 months, samples were taken again for AMH, and the data were recorded. The mean age of the study group was 27.6 ±â€…5.3 years, and the mean age of the control group was 28.65 ±â€…5.25 years (P = .298). There was no statistically significant difference between the vaccinated and nonvaccinated groups in terms of AMH levels measured at the 6th month (P = .970). When the vaccinated group was compared in terms of AMH values at the first visit before vaccination and at the 6th month after vaccination, no statistically significant difference was found between them (p:0.127) mRNA vaccination to protect against SARS-CoV-2 does not adversely affect ovarian reserve, which is an indirect indicator of fertility. mRNA vaccines continue to be the most important method of protection against epidemics. Carefully and accurately informing women who are hesitant to get vaccinated is of great importance for the success of the fight against the epidemic.


Subject(s)
COVID-19 , Ovarian Reserve , Pregnancy , Female , Humans , Young Adult , Adult , COVID-19 Vaccines/adverse effects , SARS-CoV-2 , COVID-19/prevention & control , Case-Control Studies , Vaccination , RNA, Messenger , mRNA Vaccines , Antibodies, Viral
6.
Nat Immunol ; 24(1): 186-199, 2023 01.
Article in English | MEDLINE | ID: covidwho-20244916

ABSTRACT

Most studies of adaptive immunity to SARS-CoV-2 infection focus on peripheral blood, which may not fully reflect immune responses at the site of infection. Using samples from 110 children undergoing tonsillectomy and adenoidectomy during the COVID-19 pandemic, we identified 24 samples with evidence of previous SARS-CoV-2 infection, including neutralizing antibodies in serum and SARS-CoV-2-specific germinal center and memory B cells in the tonsils and adenoids. Single-cell B cell receptor (BCR) sequencing indicated virus-specific BCRs were class-switched and somatically hypermutated, with overlapping clones in the two tissues. Expanded T cell clonotypes were found in tonsils, adenoids and blood post-COVID-19, some with CDR3 sequences identical to previously reported SARS-CoV-2-reactive T cell receptors (TCRs). Pharyngeal tissues from COVID-19-convalescent children showed persistent expansion of germinal center and antiviral lymphocyte populations associated with interferon (IFN)-γ-type responses, particularly in the adenoids, and viral RNA in both tissues. Our results provide evidence for persistent tissue-specific immunity to SARS-CoV-2 in the upper respiratory tract of children after infection.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Child , Pandemics , Adaptive Immunity , Palatine Tonsil , Antibodies, Viral
7.
Poult Sci ; 102(6): 102661, 2023 Jun.
Article in English | MEDLINE | ID: covidwho-20244886

ABSTRACT

Avian infectious bronchitis (IB) is a highly contagious disease caused by infectious bronchitis virus (IBV). Vaccination is an effective approach for controlling IBV. Therefore, reliable immune monitoring for IB is critical for poultry. In this study, a novel peptide derived from S2 protein was used to develop an enzyme-linked immunosorbent assay (ELISA) for the detection of broadly cross-reactive antibodies against IBV. The peptide-based ELISA (pELISA) showed good specificity and sensitivity in detecting IBV antibodies against different serotypes. A semilogarithmic regression method for determining IBV antibody titers was also established. Antibody titers detected by pELISA and calculated with this equation were statistically similar to those evaluated by indirect fluorescence assay (IFA). Moreover, the comparison analysis showed a 96.07% compatibility between the pELISA and IDEXX ELISA. All these data demonstrate that the pELISA generated here can be as a rapid and reliable serological surveillance tool for monitoring IBV infection or vaccination.


Subject(s)
Coronavirus Infections , Infectious bronchitis virus , Poultry Diseases , Animals , Chickens , Antibodies, Viral/analysis , Enzyme-Linked Immunosorbent Assay/veterinary , Enzyme-Linked Immunosorbent Assay/methods , Coronavirus Infections/diagnosis , Coronavirus Infections/prevention & control , Coronavirus Infections/veterinary , Peptides , Poultry Diseases/diagnosis , Poultry Diseases/prevention & control
8.
Sci Adv ; 9(23): eadg0330, 2023 06 09.
Article in English | MEDLINE | ID: covidwho-20244693

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern challenge the efficacy of approved vaccines, emphasizing the need for updated spike antigens. Here, we use an evolutionary-based design aimed at boosting protein expression levels of S-2P and improving immunogenic outcomes in mice. Thirty-six prototype antigens were generated in silico and 15 were produced for biochemical analysis. S2D14, which contains 20 computationally designed mutations within the S2 domain and a rationally engineered D614G mutation in the SD2 domain, has an ~11-fold increase in protein yield and retains RBD antigenicity. Cryo-electron microscopy structures reveal a mixture of populations in various RBD conformational states. Vaccination of mice with adjuvanted S2D14 elicited higher cross-neutralizing antibody titers than adjuvanted S-2P against the SARS-CoV-2 Wuhan strain and four variants of concern. S2D14 may be a useful scaffold or tool for the design of future coronavirus vaccines, and the approaches used for the design of S2D14 may be broadly applicable to streamline vaccine discovery.


Subject(s)
COVID-19 , SARS-CoV-2 , Animals , Mice , Antibodies, Viral , Neutralization Tests , Cryoelectron Microscopy
9.
BMJ Open ; 13(6): e071228, 2023 06 12.
Article in English | MEDLINE | ID: covidwho-20244540

ABSTRACT

OBJECTIVE: To determine the SARS-CoV-2 seroprevalence among school workers within the Greater Vancouver area, British Columbia, Canada, after the first Omicron wave. DESIGN: Cross-sectional study by online questionnaire, with blood serology testing. SETTING: Three main school districts (Vancouver, Richmond and Delta) in the Vancouver metropolitan area. PARTICIPANTS: Active school staff enrolled from January to April 2022, with serology testing between 27 January and 8 April 2022. Seroprevalence estimates were compared with data obtained from Canadian blood donors weighted over the same sampling period, age, sex and postal code distribution. PRIMARY AND SECONDARY OUTCOMES: SARS-CoV-2 nucleocapsid antibody testing results adjusted for test sensitivity and specificity, and regional variation across school districts using Bayesian models. RESULTS: Of 1850 school staff enrolled, 65.8% (1214/1845) reported close contact with a COVID-19 case outside the household. Of those close contacts, 51.5% (625/1214) were a student and 54.9% (666/1214) were a coworker. Cumulative incidence of COVID-19 positive testing by self-reported nucleic acid or rapid antigen testing since the beginning of the pandemic was 15.8% (291/1845). In a representative sample of 1620 school staff who completed serology testing (87.6%), the adjusted seroprevalence was 26.5% (95% CrI 23.9% to 29.3%), compared with 32.4% (95% CrI 30.6% to 34.5%) among 7164 blood donors. CONCLUSION: Despite frequent COVID-19 exposures reported, SARS-CoV-2 seroprevalence among school staff in this setting remained no greater than the community reference group. Results are consistent with the premise that many infections were acquired outside the school setting, even with Omicron.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , British Columbia , Cross-Sectional Studies , Bayes Theorem , Seroepidemiologic Studies , Antibodies, Viral
10.
Nat Commun ; 14(1): 3440, 2023 Jun 10.
Article in English | MEDLINE | ID: covidwho-20244495

ABSTRACT

The overall success of worldwide mass vaccination in limiting the negative effect of the COVID-19 pandemics is inevitable, however, recent SARS-CoV-2 variants of concern, especially Omicron and its sub-lineages, efficiently evade humoral immunity mounted upon vaccination or previous infection. Thus, it is an important question whether these variants, or vaccines against them, induce anti-viral cellular immunity. Here we show that the mRNA vaccine BNT162b2 induces robust protective immunity in K18-hACE2 transgenic B-cell deficient (µMT) mice. We further demonstrate that the protection is attributed to cellular immunity depending on robust IFN-γ production. Viral challenge with SARS-CoV-2 Omicron BA.1 and BA.5.2 sub-variants induce boosted cellular responses in vaccinated µMT mice, which highlights the significance of cellular immunity against the ever-emerging SARS-CoV-2 variants evading antibody-mediated immunity. Our work, by providing evidence that BNT162b2 can induce significant protective immunity in mice that are unable to produce antibodies, thus highlights the importance of cellular immunity in the protection against SARS-CoV-2.


Subject(s)
COVID-19 Vaccines , COVID-19 , Immunity, Cellular , Animals , Humans , Mice , Antibodies , Antibodies, Neutralizing , Antibodies, Viral , BNT162 Vaccine , COVID-19/prevention & control , Interferon-gamma , SARS-CoV-2 , COVID-19 Vaccines/immunology
11.
Emerg Microbes Infect ; 12(2): 2225640, 2023 Dec.
Article in English | MEDLINE | ID: covidwho-20244449

ABSTRACT

Although humoral responses elicited by infection or vaccine lost the ability to prevent transmission against Omicron, vaccine-induced antibodies may still contribute to disease attenuation through Fc-mediated effector functions. However, Fc effector function elicited by CoronaVac, as the most widely supplied inactivated vaccine globally, has not been characterized. For the first time, our study depicted Fc-mediated phagocytosis activity induced by CoronaVac, including antibody-dependent cellular phagocytosis (ADCP) and antibody-dependent neutrophil phagocytosis (ADNP) activities, and further compared with that from convalescent individuals and CoronaVac recipients with subsequent breakthrough infections. We showed that 2-dose of CoronaVac effectively induced both ADCP and ADNP, but was substantially lower compared to infection, whereas the booster dose further augmented ADCP and ADNP responses, and remained detectable for 52 weeks. Among CoronaVac recipients, ADCP and ADNP responses also demonstrated cross-reactivity against Omicron subvariants, and breakthrough infection could enhance the phagocytic response. Meanwhile, serum samples from vaccinees, convalescent individuals with wildtype infection, BA.2 and BA.5 breakthrough infection demonstrated differential cross-reactive ADCP and ADNP responses against Omicron subvariants, suggesting the different subvariants of spike antigen exposure might alter the cross-reactivity of Fc effector function. Further, ADCP and ADNP responses were strongly correlated with Spike-specific IgG responses and neutralizing activities, indicating coordinated neutralization activity, ADCP and ADNP responses triggered by CoronaVac. Of note, the ADCP and ADNP responses were more durable and cross-reactive than corresponding Spike-specific IgG titers and neutralizing activities. Our study has important implications for optimal boosting vaccine strategies that may induce potent and broad Fc-mediated phagocytic activities.


Subject(s)
Antibodies, Viral , Phagocytosis , Humans , Breakthrough Infections , Vaccines, Inactivated , Immunoglobulin G , Antibodies, Neutralizing
12.
Immunity ; 56(6): 1410-1428.e8, 2023 06 13.
Article in English | MEDLINE | ID: covidwho-20244437

ABSTRACT

Although host responses to the ancestral SARS-CoV-2 strain are well described, those to the new Omicron variants are less resolved. We profiled the clinical phenomes, transcriptomes, proteomes, metabolomes, and immune repertoires of >1,000 blood cell or plasma specimens from SARS-CoV-2 Omicron patients. Using in-depth integrated multi-omics, we dissected the host response dynamics during multiple disease phases to reveal the molecular and cellular landscapes in the blood. Specifically, we detected enhanced interferon-mediated antiviral signatures of platelets in Omicron-infected patients, and platelets preferentially formed widespread aggregates with leukocytes to modulate immune cell functions. In addition, patients who were re-tested positive for viral RNA showed marked reductions in B cell receptor clones, antibody generation, and neutralizing capacity against Omicron. Finally, we developed a machine learning model that accurately predicted the probability of re-positivity in Omicron patients. Our study may inspire a paradigm shift in studying systemic diseases and emerging public health concerns.


Subject(s)
Blood Platelets , COVID-19 , Humans , SARS-CoV-2 , Breakthrough Infections , Multiomics , Antibodies, Neutralizing , Antibodies, Viral
13.
Influenza Other Respir Viruses ; 17(6): e13144, 2023 06.
Article in English | MEDLINE | ID: covidwho-20244279

ABSTRACT

New immune evasive variants of SARS-CoV-2 continue to emerge, potentially causing new waves of covid-19 disease. Here, we evaluate levels of neutralizing antibodies against isolates of Omicron variants, including BQ.1.1 and XBB, in sera harvested 3-4 weeks after vaccination or breakthrough infections. In addition, we evaluate neutralizing antibodies in 32 sera from October 2022, to evaluate immunity in Norwegian donors prior to the winter season. Most serum samples harvested in October 2022 had low levels of neutralizing antibodies against BQ.1.1 and especially XBB, explaining why these variants and their descendants have dominated in Norway during the 2022 and 2023 winter season.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , SARS-CoV-2/genetics , COVID-19/epidemiology , Norway/epidemiology , Antibodies, Neutralizing , Antibodies, Viral
14.
Expert Rev Vaccines ; 22(1): 501-517, 2023.
Article in English | MEDLINE | ID: covidwho-20244063

ABSTRACT

INTRODUCTION: The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in significant morbidity and mortality worldwide. As SARS-CoV-2 moves into endemic status, vaccination remains a key element in protecting the health of individuals, societies, and economies worldwide. AREAS COVERED: NVX-CoV2373 (Novavax, Gaithersburg, MD) is a recombinant protein vaccine composed of SARS-CoV-2 spike trimer nanoparticles formulated with saponin-based Matrix-M™ adjuvant (Novavax, Gaithersburg, MD). NVX-CoV2373 is authorized for emergency use in adults and adolescents aged ≥12 years in the United States and numerous other countries. EXPERT OPINION: In clinical trials, NVX-CoV2373 showed tolerable reactogenicity and favorable safety profiles characterized by mostly mild-to-moderate adverse events of short duration and by low rates of severe and serious adverse events comparable to those seen with placebo. The two-dose primary vaccination series resulted in robust increases in anti-spike protein immunoglobulin G, neutralizing antibody titers, and cellular immune responses. NVX-CoV2373 vaccination was associated with complete protection against severe disease and a high (90%) rate of protection against symptomatic disease in adults, including symptomatic disease caused by SARS-CoV-2 variants. Additionally, the NVX-CoV2373 adjuvanted recombinant protein platform offers a means to address issues of COVID-19 vaccination hesitancy and global vaccine equity.


Subject(s)
COVID-19 , Vaccines , Adolescent , Adult , Humans , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , Immunogenicity, Vaccine , SARS-CoV-2 , Child
15.
Viruses ; 15(5)2023 04 29.
Article in English | MEDLINE | ID: covidwho-20243887

ABSTRACT

This study evaluated the impact of the coronavirus disease 2019 (COVID-19) pandemic on the occurrence of maternal primary cytomegalovirus (CMV) infection in Japan. We performed a nested case-control study using data from maternal CMV antibody screening under the Cytomegalovirus in Mother and infant-engaged Virus serology (CMieV) program in Mie, Japan. Pregnant women with negative IgG antibodies at ≤20 weeks of gestation who were retested at ≥28 weeks were enrolled. The study period was divided into 2015-2019 as the pre-pandemic and 2020-2022 as the pandemic period, and the study site included 26 institutions conducting the CMieV program. The incidence rate of maternal IgG seroconversion was compared between the pre-pandemic (7008 women enrolled) and pandemic (2020, 1283 women enrolled; 2021, 1100 women; and 2022, 398 women) periods. Sixty-one women in the pre-pandemic period and five, four, and five women during 2020, 2021, and 2022, respectively, showed IgG seroconversion. The incidence rates in 2020 and 2021 were lower (p < 0.05) than that in the pre-pandemic period. Our data suggest a transient decrease in the incidence of maternal primary CMV infection in Japan during the COVID-19 pandemic, which could be due to prevention and hygiene measures taken at the population level.


Subject(s)
COVID-19 , Cytomegalovirus Infections , Pregnancy Complications, Infectious , Pregnancy , Female , Humans , Cytomegalovirus , Incidence , Pandemics , Pregnancy Complications, Infectious/epidemiology , Pregnancy Complications, Infectious/prevention & control , Pregnancy Complications, Infectious/diagnosis , Case-Control Studies , Japan/epidemiology , Immunoglobulin G , COVID-19/epidemiology , Cytomegalovirus Infections/epidemiology , Cytomegalovirus Infections/prevention & control , Cytomegalovirus Infections/diagnosis , Antibodies, Viral
16.
Front Cell Infect Microbiol ; 13: 1197349, 2023.
Article in English | MEDLINE | ID: covidwho-20243868

ABSTRACT

Introduction: We examined the neutralizing antibody production efficiency of the second and third severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine doses (2nd- and 3rd-dose) and neutralizing activity on mutant strains, including, the Ancestral, Beta and Omicron strains using green fluorescent protein-carrying recombinant SARS-CoV-2, in living-donor liver transplantation (LDLT) recipients. Methods: The patients who were administered vaccines other than Pfizer- BioNTechBNT162b2 and who had coronavirus disease 2019 in this study period were excluded. We enrolled 154 LDLT recipients and 50 healthy controls. Result: The median time were 21 days (between 1st and 2nd vaccination) and 244 days (between 2nd and 3rd vaccination). The median neutralizing antibody titer after 2nd-dose was lower in LDLT recipients than in controls (0.46 vs 1.00, P<0.0001). All controls had SARS-CoV-2 neutralizing antibodies, whereas 39 LDLT recipients (25.3%) had no neutralizing antibodies after 2nd-dose; age at vaccination, presence of ascites, multiple immunosuppressive treatments, and mycophenolate mofetil treatment were significant risk factors for nonresponder. The neutralizing activities of recipient sera were approximately 3-fold and 5-fold lower than those of control sera against the Ancestral and Beta strains, respectively. The median antibody titer after 3rd-dose was not significantly different between recipients and controls (1.02 vs 1.22, p=0.0758); only 5% recipients was non-responder. The neutralizing activity after third dose to Omicron strains were enhanced and had no significant difference between two groups. Conclusion: Only the 2nd-dose was not sufficiently effective in recipients; however, 3rd-dose had sufficient neutralizing activity against the mutant strain and was as effective as that in healthy controls.


Subject(s)
COVID-19 , Liver Transplantation , Humans , SARS-CoV-2/genetics , BNT162 Vaccine , COVID-19/prevention & control , Living Donors , Antibodies, Neutralizing , Antibodies, Viral , Vaccination
17.
J Transl Med ; 21(1): 374, 2023 Jun 08.
Article in English | MEDLINE | ID: covidwho-20243655

ABSTRACT

BACKGROUND: Although mRNA vaccines have overall efficacy preventing morbidity/mortality from SARS-CoV-2 infection, immunocompromised persons remain at risk. Antibodies mostly prevent early symptomatic infection, but cellular immunity, particularly the virus-specific CD8+ T cell response, is protective against disease. Defects in T cell responses to vaccination have not been well characterized in immunocompromised hosts; persons with lung transplantation are particularly vulnerable to vaccine failure with severe illness. METHODS: Comparison groups included persons with lung transplantation and no history of COVID-19 (21 and 19 persons after initial mRNA vaccination and a third booster vaccination respectively), 8 lung transplantation participants recovered from COVID-19, and 22 non-immunocompromised healthy control individuals after initial mRNA vaccination (without history of COVID-19). Anti-spike T cell responses were assayed by stimulating peripheral blood mononuclear cells (PBMCs) with pooled small overlapping peptides spanning the SARS-CoV-2 spike protein, followed by intracellular cytokine staining (ICS) and flow cytometry for release of cytokines in response to stimulation, including negative controls (no peptide stimulation) and positive controls (phorbol myristate acetate [PMA] and ionomycin stimulation). To evaluate for low frequency memory responses, PBMCs were cultured in the presence of the mRNA-1273 vaccine for 14 days before this evaluation. RESULTS: Ionophore stimulation of PBMCs revealed a less inflammatory milieu in terms of interleukin (IL)-2, IL-4, and IL-10 profiling in lung transplantation individuals, reflecting the effect of immunosuppressive treatments. Similar to what we previously reported in healthy vaccinees, spike-specific responses in lung transplantation recipients were undetectable (< 0.01%) when tested 2 weeks after vaccination or later, but were detectable after in vitro culture of PBMCs with mRNA-1273 vaccine to enrich memory T cell responses. This was also seen in COVID-19-recovered lung transplantation recipients. Comparison of their enriched memory responses to controls revealed relatively similar CD4+ T cell memory, but markedly reduced CD8+ T cell memory both after primary vaccination or a booster dose. These responses were not correlated to age or time after transplantation. The vaccine-induced CD4+ and CD8+ responses correlated well in the healthy control group, but poorly in the transplantation groups. CONCLUSIONS: These results reveal a specific defect in CD8+ T cells, which have key roles both in transplanted organ rejection but also antiviral effector responses. Overcoming this defect will require strategies to enhance vaccine immunogenicity in immunocompromised persons.


Subject(s)
COVID-19 , Transplant Recipients , Humans , CD8-Positive T-Lymphocytes , 2019-nCoV Vaccine mRNA-1273 , SARS-CoV-2 , Leukocytes, Mononuclear , COVID-19/prevention & control , Vaccination , Antibodies , Cytokines , Lung , Antibodies, Viral
18.
ACS Appl Mater Interfaces ; 15(23): 27612-27623, 2023 Jun 14.
Article in English | MEDLINE | ID: covidwho-20243632

ABSTRACT

The extensive research into developing novel strategies for detecting respiratory syndrome coronavirus 2 (SARS-CoV-2) antigens in clinical specimens, especially the sensitive point-of-care testing method, is still urgently needed to reach rapid screening of viral infections. Herein, a new lateral flow immunoassay (LFIA) platform was reported for the detection of SARS-CoV-2 spike-S1 protein antigens, in which four sensitive and specific SARS-CoV-2 mouse monoclonal antibodies (MmAbs) were tailored by using quantum dot (QD)-loaded dendritic mesoporous silica nanoparticles modified further for achieving the -COOH group surface coating (named Q/S-COOH nanospheres). Importantly, compact QD adsorption was achieved in mesoporous channels of silica nanoparticles on account of highly accessible central-radial pores and electrostatic interactions, leading to significant signal amplification. As such, a limit of detection for SARS-CoV-2 spike-S1 testing was found to be 0.03 ng/mL, which is lower compared with those of AuNPs-LFIA (traditional colloidal gold nanoparticles, Au NPs) and enzyme-linked immunosorbent assay methods. These results show that optimizing the affinity of antibody and the intensity of fluorescent nanospheres simultaneously is of great significance to improve the sensitivity of LFIA.


Subject(s)
COVID-19 , Metal Nanoparticles , Nanospheres , Animals , Mice , SARS-CoV-2 , COVID-19/diagnosis , Gold , Silicon Dioxide , Immunoassay/methods , Antibodies, Viral , Sensitivity and Specificity
19.
Virol J ; 20(1): 106, 2023 05 29.
Article in English | MEDLINE | ID: covidwho-20243616

ABSTRACT

BACKGROUND: The pathogenicity and virulence of the Omicron strain have weakened significantly pathogenesis of Omicron variants. Accumulating data indicated accessory proteins play crucial roles in host immune evasion and virus pathogenesis of SARS-CoV-2. Therefore, the impact of simultaneous deletion of accessory protein ORF7a, ORF7b and ORF8 on the clinical characteristics and specific immunity in Omicron breakthrough infected patients (BIPs) need to be verified. METHODS: Herein, plasma cytokines were identified using a commercial Multi-cytokine detection kit. Enzyme-linked immunosorbent assay and pseudovirus neutralization assays were utilized to determine the titers of SARS-CoV-2 specific binding antibodies and neutralizing antibodies, respectively. In addition, an enzyme-linked immunospot assay was used to quantify SARS-CoV-2 specific T cells and memory B cells. RESULTS: A local COVID-19 outbreak was caused by the Omicron BA.2 variant, which featured a deletion of 871 base pairs (∆871 BA.2), resulting in the removal of ORF7a, ORF7b, and ORF8. We found that hospitalized patients with ∆871 BA.2 had significantly shorter hospital stays than those with wild-type (WT) BA.2. Plasma cytokine levels in both ∆871 BA.2 and WT BA.2 patients were within the normal range of reference, and there was no notable difference in the titers of SARS-CoV-2 ancestor or Omicron-specific binding IgG antibodies, neutralizing antibody titers, effector T cells, and memory B cells frequencies between ∆871 BA.2 and WT BA.2 infected adult patients. However, antibody titers in ∆871 BA.2 infected adolescents were higher than in adults. CONCLUSIONS: The simultaneous deletion of ORF7a, ORF7b, and ORF8 facilitates the rapid clearance of the BA.2 variant, without impacting cytokine levels or affecting SARS-CoV-2 specific humoral and cellular immunity in Omicron-infected individuals.


Subject(s)
COVID-19 , Adolescent , Adult , Humans , SARS-CoV-2/genetics , Antibodies, Neutralizing , Antibodies, Viral , Cytokines , Enzyme-Linked Immunospot Assay
20.
Cell Host Microbe ; 31(6): 902-916, 2023 Jun 14.
Article in English | MEDLINE | ID: covidwho-20243579

ABSTRACT

Although the development and clinical application of SARS-CoV-2 vaccines during the COVID-19 pandemic demonstrated unprecedented vaccine success in a short time frame, it also revealed a limitation of current vaccines in their inability to provide broad-spectrum or universal protection against emerging variants. Broad-spectrum vaccines, therefore, remain a dream and challenge for vaccinology. This review will focus on current and future efforts in developing universal vaccines targeting different viruses at the genus and/or family levels, with a special focus on henipaviruses, influenza viruses, and coronaviruses. It is evident that strategies for developing broad-spectrum vaccines will be virus-genus or family specific, and it is almost impossible to adopt a universal approach for different viruses. On the other hand, efforts in developing broad-spectrum neutralizing monoclonal antibodies have been more successful and it is worth considering broad-spectrum antibody-mediated immunization, or "universal antibody vaccine," as an alternative approach for early intervention for future disease X outbreaks.


Subject(s)
COVID-19 , Influenza Vaccines , Orthomyxoviridae Infections , Humans , COVID-19 Vaccines , Pandemics/prevention & control , Antibodies, Viral , COVID-19/prevention & control , SARS-CoV-2 , Antibodies, Neutralizing
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