Nasal and Salivary Mucosal Humoral Immune Response Elicited by mRNA BNT162b2 COVID-19 Vaccine Compared to SARS-CoV-2 Natural Infection

SARS-CoV-2 antibody assays are crucial in managing the COVID-19 pandemic. Approved mRNA COVID-19 vaccines are well known to induce a serum antibody responses against the spike protein and its RBD. Mucosal immunity plays a major role in the fight against COVID-19 directly at the site of virus entry; however, vaccine abilities to elicit mucosal immune responses have not been reported. We detected anti-SARS-CoV-2 IgA-S1 and IgG-RBD in three study populations (healthy controls, vaccinated subjects, and subjects recovered from COVID-19 infection) on serum, saliva, and nasal secretions using two commercial immunoassays (ELISA for IgA-S1 and chemiluminescent assay for IgG-RBD). Our results show that the mRNA BNT162b2 vaccine Comirnaty (Pfizer/BioNTech, New York, NY, USA) determines the production of nasal and salivary IgA-S1 and IgG-RBD against SARS-CoV-2. This mucosal humoral immune response is stronger after the injection of the second vaccine dose compared to subjects recovered from COVID-19. Since there is a lack of validated assays on saliva and nasal secretions, this study shows that our pre-analytical and analytical procedures are consistent with the data. Our findings indicate that the mRNA COVID-19 vaccine elicits antigen-specific nasal and salivary immune responses, and that mucosal antibody assays could be used as candidates for non-invasive monitoring of vaccine-induced protection against viral infection.

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Function Is More Reliable than Quantity to Follow Up the Humoral Response to the Receptor-Binding Domain of SARS-CoV-2-Spike Protein after Natural Infection or COVID-19 Vaccination

Viruses ◽

10.3390/v13101972 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1972

Author(s):

Carlos A. Sariol ◽

Petraleigh Pantoja ◽

Crisanta Serrano-Collazo ◽

Tiffany Rosa-Arocho ◽

Albersy Armina-Rodríguez ◽

...

Keyword(s):

Immune Response ◽

Natural Infection ◽

Vaccine Dose ◽

Humoral Response ◽

Neutralizing Antibody ◽

Viral Neutralization ◽

Neutralizing Activity ◽

Humoral Immune ◽

Antibody Assays ◽

Novel Coronavirus

Both the SARS-CoV-2 pandemic and emergence of variants of concern have highlighted the need for functional antibody assays to monitor the humoral response over time. Antibodies directed against the spike (S) protein of SARS-CoV-2 are an important component of the neutralizing antibody response. In this work, we report that in a subset of patients—despite a decline in total S-specific antibodies—neutralizing antibody titers remain at a similar level for an average of 98 days in longitudinal sampling of a cohort of 59 Hispanic/Latino patients exposed to SARS-CoV-2. Our data suggest that 100% of seroconverting patients make detectable neutralizing antibody responses which can be quantified by a surrogate viral neutralization test. Examination of sera from ten out of the 59 subjects which received mRNA-based vaccination revealed that both IgG titers and neutralizing activity of sera were higher after vaccination compared to a cohort of 21 SARS-CoV-2 naïve subjects. One dose was sufficient for the induction of a neutralizing antibody, but two doses were necessary to reach 100% surrogate virus neutralization in subjects irrespective of previous SARS-CoV-2 natural infection status. Like the pattern observed after natural infection, the total anti-S antibodies titers declined after the second vaccine dose; however, neutralizing activity remained relatively constant for more than 80 days after the first vaccine dose. Furthermore, our data indicates that—compared with mRNA vaccination—natural infection induces a more robust humoral immune response in unexposed subjects. This work is an important contribution to understanding the natural immune response to the novel coronavirus in a population severely impacted by SARS-CoV-2. Furthermore, by comparing the dynamics of the immune response after the natural infection vs. the vaccination, these findings suggest that functional neutralizing antibody tests are more relevant indicators than the presence or absence of binding antibodies.

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TLR4 regulates rabies virus-induced humoral immunity through recruitment of cDC2 to lymph organs

Journal of Virology ◽

10.1128/jvi.00829-21 ◽

2021 ◽

Author(s):

Chen Chen ◽

Chengguang Zhang ◽

Haoqi Li ◽

Zongmei Wang ◽

Yueming Yuan ◽

...

Keyword(s):

Immune Response ◽

Immune Responses ◽

Rabies Virus ◽

Humoral Immunity ◽

Humoral Immune Response ◽

Critical Role ◽

Wild Type ◽

Humoral Immune ◽

Specific Igg ◽

Molecular Patterns

Rabies, caused by rabies virus (RABV), is fatal to both humans and animals around the world. Effective clinical therapy for rabies has not been achieved, and vaccination is the most effective means of preventing and controlling rabies. Although different vaccines, such as live attenuated and inactivated vaccines, can induce different immune responses, different expression of pattern recognition receptors (PRRs) also causes diverse immune responses. Toll-like receptor 4 (TLR4) is a pivotal PRR that induces cytokine production and bridges innate and adaptive immunity. Importantly, TLR4 recognizes various virus-derived pathogen-associated molecular patterns (PAMPs) and virus-induced damage-associated molecular patterns (DAMPs), usually leading to the activation of immune cells. However, the role of TLR4 in the humoral immune response induced by RABV has not been revealed yet. Based on TLR4-deficient ( TLR4 -/- ) and wild-type (WT) mouse models, we report that TLR4-dependent recruitment of the conventional type-2 dendritic cells (CD8α - CD11b + cDC2) into secondary lymph organs (SLOs) is critical for antigen presentation. cDC2-initiated differentiation of Tfh cells promotes the proliferation of germinal centre (GC) B cells, the formation of GCs, and the production of plasma cells (PCs), all of which contribute to the production of RABV-specific IgG and virus-neutralizing antibodies (VNAs). Collectively, our work demonstrates that TLR4 is necessary for the recruitment of cDC2 and for the induction of RABV-induced humoral immunity, which is regulated by the cDC2-Tfh-GC B axis. IMPORTANCE Vaccination is the most efficient method to prevent rabies. TLR4, a well-known immune sensor, plays a critical role in initiating innate immune response. Here, we found that TLR4 deficiency ( TLR4 -/- ) mice suppressed the induction of humoral immune response after immunization with rabies virus (RABV), including reduced production of VNAs and RABV-specific IgG, compared with that occurred in wild-type (WT) mice. As a consequence, TLR4 -/- mice exhibited higher mortality than WT mice after challenge with virulent RABV. Importantly, further investigation found that TLR4 signaling promoted the recruitment of cDC2 (CD8α + CD11b - ), a subset of cDCs known to induce CD4 + T cell immunity through their MHC-II presentation machinery. Our results imply that TLR4 is indispensable for an efficient humoral response to rabies vaccine, which provides new insight into the development of novel rabies vaccines.

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The time course of the humoral immune response to rhinovirus infection

Epidemiology and Infection ◽

10.1017/s095026880003106x ◽

1989 ◽

Vol 103 (3) ◽

pp. 659-669 ◽

Cited By ~ 62

Author(s):

W. S. Barclay ◽

W. Al-Nakib ◽

P. G. Higgins ◽

D. A. J. Tyrrell

Keyword(s):

Immune Response ◽

Specific Antibody ◽

Humoral Immune Response ◽

Time Course ◽

Human Rhinovirus ◽

Specific Antibodies ◽

Humoral Immune ◽

Rhinovirus Infection ◽

Nasal Secretions

SUMMARYThe specific humoral immune response of 17 volunteers to infection with human rhinovirus type 2 (HRV-2) has been measured both by neutralization and by ELISA. Six volunteers who had HRV-2-specific antibodies in either serum or nasal secretions before HRV-2 inoculation were resistant to infection and illness. Of the remaining 11 volunteers who had little pre-existing HRV-2-specific antibody, one was immune but 10 became infected and displayed increases in HRV-2-specific antibodies. These antibodies first increased 1–2 weeks after infection and reached a maximum at 5 weeks. All six resistant volunteers who had high pre-existing antibody and eight of the volunteers who became infected maintained their HRV-2-specific antibody for at least 1 year. At this time they were protected against reinfection. Two volunteers showed decreases in HRV-2-specific antibodies from either serum or nasal secretions. They became infected but not ill after HRV-2 inoculation 1 year later.

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Should be a Third Dose of BNT162b2 mRNA COVID-19-Vaccine Administered in Patients with Myelofibrosis Under Ruxolitinib?

Blood ◽

10.1182/blood-2021-146381 ◽

2021 ◽

Vol 138 (Supplement 1) ◽

pp. 2573-2573

Author(s):

Giovanni Caocci ◽

Olga Mulas ◽

Daniela Mantovani ◽

Alessandro Costa ◽

Andrea Galizia ◽

...

Keyword(s):

Immune Response ◽

Humoral Immune Response ◽

Present Report ◽

Univariate Analysis ◽

Vaccine Dose ◽

Humoral Response ◽

The Other ◽

World Health ◽

International Prognostic Scoring System ◽

Humoral Immune

Abstract Introduction. Patients with Myelofibrosis (MF) are considered fragile and thus eligible in Italy for COVID-19 BNT162b2 mRNA vaccination. According to the International Prognostic Scoring System (IPSS), patients with intermediate and high MF, may receive clinical benefits from ruxolitinib, the first approved JAK1/JAK2 inhibitor. Given the potent anti-inflammatory properties of ruxolitinib against immunocompetent cells, we previously reported a lower but non-statistically absolute IgG anti-Spike humoral response in vaccinated MF patients treated with ruxolitinib. In the present report we extended the cohort of MF patients. Methods. All MF patients received 2 injections of 30 ug per dose of BNT162b2 mRNA COVID-19 vaccine 3 weeks apart, according to the standard protocol. After injection, mild pain at the injection site was frequently reported. No serious adverse events were registered. The serum level of IgG anti-Spike glycoprotein was tested after a median time of 45 days (range 40-60) from the second vaccine dose, using the approved anti-SARS-CoV-2 IgG CLIA (LIAISON® SARS-CoV-2 TrimericS IgG assay, Diasorin, Saluggia, Italy). An Arbitrary Units per milliliter (AU/mL) ratio of <12.0 was considered to be negative, 12.0-15.0 AU/mL to be borderline and >15 AU/mL to be positive. A conversion of AU/mL to binding antibody units (BAU/mL) as recommended by the World Health Organization (WHO) guidelines was achieved considering the following equation: BAU/mL = 2.6*AU/mL. Results. Overall, 30 MF patients (median age 65 years, range 48-83) were vaccinated. A diagnosis of primary MF was reported in 21 cases (70%), post essential thrombocythemia-MF in 6 (20%) patients and post polycythemia vera-MF in 3 (10%) patients; 23 out of 30 patients (76.6%) were positive for the JAK2V617F, 5 (16.6%) for CALR mutation, 1 (3.3%) for MPL mutation and 1 patient (3.3%) resulted triple negative. Splenomegaly was observed in 14 patients (46%) and 19 (63.3%) reported comorbidities. Nineteen patients (63.3%) were classified as DIPSS low or intermediate-1 risk, and 11 (36.6%) as intermediate-2 or high risk. Fifteen patients (50%) were receiving ruxolitinib, at a median total dose of 20 mg/die (range 20-40 mg) and the remaining 15 patients other treatments (8 patients hydroxyurea and 7 only supportive therapy). None of the patients reported COVID-19 infection neither previous nor subsequently to vaccination. Overall, a positive immune response against COVID-19 was observed in 8 out of 15 patients (53.3%) in the ruxolitinib group, in comparison with 13 out 15 patients (86.6%) in the other treatment group (p=0,046). The absolute IgG anti-Spike value was lower in the ruxolitinib group (median 35.2±49.81) in comparison with the other group (median 226.1±163.9; p=<0.001), Figure 1. In univariate analysis, only ruxolitinib treatment was found associated with a lower humoral immune response to the vaccine. Conclusions. MF patients under ruxolitinib achieved a lower humoral immune response in comparison with MF patients who underwent other treatments. No COVID-19 infection was observed in both groups after vaccination, after a median follow up of 3 months since the second dose. Whether patients with a potential insufficient humoral response to vaccine will benefit from a third dose of BNT162b2 mRNA COVID-19 vaccine is a matter of further investigation. Our preliminary data need to be confirmed in larger cohort of MF patients. Figure 1 Figure 1. Disclosures Murru: Abbvie: Consultancy, Honoraria, Other: travel and accommodation; Janssen: Consultancy, Honoraria.

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Recombinant Mycobacterium paragordonae Expressing SARS-CoV-2 Receptor-Binding Domain as a Vaccine Candidate Against SARS-CoV-2 Infections

Frontiers in Immunology ◽

10.3389/fimmu.2021.712274 ◽

2021 ◽

Vol 12 ◽

Author(s):

Byoung-Jun Kim ◽

Hyein Jeong ◽

Hyejun Seo ◽

Mi-Hyun Lee ◽

Hyun Mu Shin ◽

...

Keyword(s):

Immune Response ◽

Single Dose ◽

Immune Responses ◽

Receptor Binding ◽

Humoral Immune Response ◽

Vaccine Candidate ◽

Binding Domain ◽

Receptor Binding Domain ◽

Live Virus ◽

Humoral Immune

At present, concerns that the recent global emergence of SARS-CoV-2 variants could compromise the current vaccines have been raised, highlighting the urgent demand for new vaccines capable of eliciting T cell-mediated immune responses, as well as B cell-mediated neutralizing antibody production. In this study, we developed a novel recombinant Mycobacterium paragordonae expressing the SARS-CoV-2 receptor-binding domain (RBD) (rMpg-RBD-7) that is capable of eliciting RBD-specific immune responses in vaccinated mice. The potential use of rMpg-RBD-7 as a vaccine for SARS-CoV-2 infections was evaluated in in vivo using mouse models of two different modules, one for single-dose vaccination and the other for two-dose vaccination. In a single-dose vaccination model, we found that rMpg-RBD-7 versus a heat-killed strain could exert an enhanced cell-mediated immune (CMI) response, as well as a humoral immune response capable of neutralizing the RBD and ACE2 interaction. In a two-dose vaccination model, rMpg-RBD-7 in a two-dose vaccination could also exert a stronger CMI and humoral immune response to neutralize SARS-CoV-2 infections in pseudoviral or live virus infection systems, compared to single dose vaccinations of rMpg-RBD or two-dose RBD protein immunization. In conclusion, our data showed that rMpg-RBD-7 can lead to an enhanced CMI response and humoral immune responses in mice vaccinated with both single- or two-dose vaccination, highlighting its feasibility as a novel vaccine candidate for SARS-CoV-2. To the best of our knowledge, this study is the first in which mycobacteria is used as a delivery system for a SARS-CoV-2 vaccine.

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Association between Reactogenicity and Immunogenicity after Vaccination with BNT162b2

Vaccines ◽

10.3390/vaccines9101089 ◽

2021 ◽

Vol 9 (10) ◽

pp. 1089

Author(s):

Stilla Bauernfeind ◽

Bernd Salzberger ◽

Florian Hitzenbichler ◽

Karolina Scigala ◽

Sebastian Einhauser ◽

...

Keyword(s):

Immune Response ◽

T Cell ◽

Immune Responses ◽

Humoral Immune Response ◽

Adverse Reactions ◽

Medical Center ◽

Neutralization Activity ◽

Humoral Immune ◽

Cell Mediated Immune Response ◽

Severe Adverse Reactions

It is not clear whether there is an association between adverse reactions and immune response after vaccination. Seven hundred and thirty-five vaccinees from our University Medical Center vaccination clinic provided information about sex, age and adverse reactions after first and second vaccination with BNT162b2. Adverse reactions were categorized into three groups: no or minor on the injection side, moderate (not further classified) and severe—defined as any symptom(s) resulting in sick leave. We chose 38 vaccinees with the most severe adverse reactions and compared their humoral and T-cell-mediated immune responses after second vaccination with those of 38 sex and age matched controls without or only minor injection-side related adverse reactions. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) anti-receptor binding domain (RBD) IgG titers were detectable in all participants (median 5528; range 958–26,285). Men with severe adverse reactions had 1.5-fold higher median SARS-CoV-2 RBD IgG titers compared to men without adverse reactions (median 7406 versus 4793; p < 0.001). Similarly; neutralization activity was significantly higher in men with severe adverse reactions (half maximal inhibitory concentrations (IC50) median 769 versus 485; p < 0.001). Reactogenicity did not influence humoral immune response in women nor T-cell-mediated immune response in any sex. To conclude; adverse reactions after vaccination with BNT162b2 do influence humoral immune response yet only in men and are not a prerequisite for a robust antibody response.

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Typically asymptomatic but with robust antibody formation: Childrens unique humoral immune response to SARS-CoV-2

10.1101/2021.07.20.21260863 ◽

2021 ◽

Author(s):

Hanna Renk ◽

Alex Dulovic ◽

Matthias Becker ◽

Dorit Fabricius ◽

Maria Zernickel ◽

...

Keyword(s):

Immune Response ◽

Humoral Immune Response ◽

Age Groups ◽

Asymptomatic Infection ◽

Serological Response ◽

Vaccination Programs ◽

Humoral Immune ◽

Viral Spread ◽

Antibody Assays

Background: Long-term persistence of antibodies against SARS-CoV-2, particularly the SARS-CoV-2 Spike Trimer, determines individual protection against infection and potentially viral spread. The quality of children's natural humoral immune response following SARS-CoV-2 infection is yet incompletely understood but crucial to guide pediatric SARS-CoV-2 vaccination programs. Methods: In this prospective observational multi-center cohort study, we followed 328 households, consisting of 548 children and 717 adults, with at least one member with a previous laboratory-confirmed SARS-CoV-2 infection. The serological response was assessed at 3-4 months and 11-12 months after infection using a bead-based multiplex immunoassay for 23 human coronavirus antigens including SARS-CoV-2 and its Variants of Concern (VOC) and endemic human coronaviruses (HCoVs), and additionally by three commercial SARS-CoV-2 antibody assays. Results: Overall, 33.76% of SARS-CoV-2 exposed children and 57.88% adults were seropositive. Children were five times more likely to have seroconverted without symptoms compared to adults. Despite the frequently asymptomatic course of infection, children had higher specific antibody levels, and their antibodies persisted longer than in adults (96.22% versus 82.89% still seropositive 11-12 months post infection). Of note, symptomatic and asymptomatic infections induced similar humoral responses in all age groups. In symptomatic children, only dysgeusia was found as diagnostic indicator of COVID-19. SARS-CoV-2 infections occurred independent of HCoV serostatus. Antibody binding responses to VOCs were similar in children and adults, with reduced binding for the Beta variant in both groups. Conclusions: The long-term humoral immune response to SARS-CoV-2 infection in children is robust and may provide long-term protection even after asymptomatic infection. (Study ID at German Clinical Trials Register: 00021521)

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Robust and durable serological response following pediatric SARS-CoV-2 infection

Nature Communications ◽

10.1038/s41467-021-27595-9 ◽

2022 ◽

Vol 13 (1) ◽

Author(s):

Hanna Renk ◽

Alex Dulovic ◽

Alina Seidel ◽

Matthias Becker ◽

Dorit Fabricius ◽

...

Keyword(s):

Immune Response ◽

Humoral Immune Response ◽

Age Groups ◽

Asymptomatic Infection ◽

Pseudotyped Virus ◽

Serological Response ◽

Vaccination Programs ◽

Humoral Immune ◽

Antibody Assays ◽

Human Coronaviruses

AbstractThe quality and persistence of children’s humoral immune response following SARS-CoV-2 infection remains largely unknown but will be crucial to guide pediatric SARS-CoV-2 vaccination programs. Here, we examine 548 children and 717 adults within 328 households with at least one member with a previous laboratory-confirmed SARS-CoV-2 infection. We assess serological response at 3–4 months and 11–12 months after infection using a bead-based multiplex immunoassay for 23 human coronavirus antigens including SARS-CoV-2 and its Variants of Concern (VOC) and endemic human coronaviruses (HCoVs), and additionally by three commercial SARS-CoV-2 antibody assays. Neutralization against wild type SARS-CoV-2 and the Delta VOC are analysed in a pseudotyped virus assay. Children, compared to adults, are five times more likely to be asymptomatic, and have higher specific antibody levels which persist longer (96.2% versus 82.9% still seropositive 11–12 months post infection). Of note, symptomatic and asymptomatic infections induce similar humoral responses in all age groups. SARS-CoV-2 infection occurs independent of HCoV serostatus. Neutralization responses of children and adults are similar, although neutralization is reduced for both against the Delta VOC. Overall, the long-term humoral immune response to SARS-CoV-2 infection in children is of longer duration than in adults even after asymptomatic infection.

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Reduced schedule of human anti rabies immunization with Fuenzalida & Palacios vaccine

Revista do Instituto de Medicina Tropical de São Paulo ◽

10.1590/s0036-46651989000100005 ◽

1989 ◽

Vol 31 (1) ◽

pp. 23-27 ◽

Cited By ~ 4

Author(s):

Carlos Roberto Zanetti ◽

Silvana Regina Favoretto ◽

Milene Silva Tino ◽

Avelino Albas ◽

Elizabeth Juliana G. Valentini ◽

...

Keyword(s):

Immune Response ◽

Immune Responses ◽

Humoral Immune Response ◽

The Other ◽

Double Dose ◽

Humoral Immune ◽

Cellular Immune Responses ◽

Lymphoblastic Transformation ◽

Cellular Immune

The present study evaluates the humoral and cellular immune responses in 35 volunteers submited to short antirabies vaccination schedules with the Fuenzalida & Palacios vaccine based on the administration of doses on non consecutive days. The volunteers were divided into two groups. The first group received a total number of five doses given on days 0, 4, 7, 20 and 35. The other group received four doses, the first one being a double dose given on day 0 and than three other single doses on days 7, 20 and 35. The evaluation of humoral immune response was carried out by serum neutralization (SN) and indirect immunofluorescense (IIF) tests, while the cellular immune response was evaluated by lymphoblastic transformation assay (LTA) and skin test (ST). According to our results these reduced schedules elicited early and effective humoral and cellulafimmune responses to rabies antigen suggesting that new reduced schedules should be extensively studied in order to give the proper bases to the proposition of changes in the current long-term schedule.

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