IgA Levels In Saliva Research Articles

Serum and Salivary IgG and IgA Response After COVID-19 Messenger RNA Vaccination

There is still considerable controversy in the literature regarding the capacity of intramuscular messenger RNA (mRNA) vaccination to induce a mucosal immune response. To compare serum and salivary IgG and IgA levels among mRNA-vaccinated individuals with or without previous SARS-CoV-2 infection. In this cohort study, SARS-CoV-2-naive participants and those with previous infection were consecutively included in the CoviCompare P and CoviCompare M mRNA vaccination trials and followed up to day 180 after vaccination with either the BNT162b2 (Pfizer-BioNTech) vaccine or the mRNA-1273 (Moderna) vaccine at the beginning of the COVID-19 vaccination campaign (from February 19 to June 8, 2021) in France. Data were analyzed from October 25, 2022, to July 13, 2023. An ultrasensitive digital enzyme-linked immunosorbent assay was used for the comparison of SARS-CoV-2 spike-specific serum and salivary IgG and IgA levels. Spike-specific secretory IgA level was also quantified at selected times. A total of 427 individuals were included in 3 groups: participants with SARS-CoV-2 prior to vaccination who received 1 single dose of BNT162b2 (Pfizer-BioNTech) (n = 120) and SARS-CoV-2-naive individuals who received 2 doses of mRNA-1273 (Moderna) (n = 172) or 2 doses of BNT162b2 (Pfizer-BioNTech) (n = 135). The median age was 68 (IQR, 39-75) years, and 228 (53.4%) were men. SARS-CoV-2 spike-specific IgG saliva levels increased after 1 or 2 vaccine injections in individuals with previous infection and SARS-CoV-2-naive individuals. After vaccination, SARS-CoV-2-specific saliva IgA levels, normalized with respect to total IgA levels, were significantly higher in participants with previous infection, as compared with the most responsive mRNA-1273 (Moderna) recipients (median normalized levels, 155 × 10-5 vs 37 × 10-5 at day 29; 107 × 10-5 vs 54 × 10-5 at day 57; and 104 × 10-5 vs 70 × 10-5 at day 180 [P < .001]). In contrast, compared with day 1, spike-specific IgA levels in the BNT162b2-vaccinated SARS-CoV-2-naive group increased only at day 57 (36 × 10-5 vs 49 × 10-5 [P = .01]). Bona fide multimeric secretory IgA levels were significantly higher in individuals with previous infection compared with SARS-CoV-2-naive individuals after 2 antigenic stimulations (median optical density, 0.36 [IQR, 0.16-0.63] vs 0.16 [IQR, 0.10-0.22]; P < .001). The findings of this cohort study suggest that mRNA vaccination was associated with mucosal immunity in individuals without prior SARS-CoV-2 infection, but at much lower levels than in previously infected individuals. Further studies are needed to determine the association between specific saliva IgA levels and prevention of infection or transmission.

Detection of SARS-CoV-2-specific mucosal antibodies in saliva following concomitant COVID-19 and influenza vaccination in the ComFluCOV trial

The ComFluCOV trial randomized 679 participants to receive an age-appropriate influenza vaccine, or placebo, alongside their second COVID-19 vaccine. Concomitant administration was shown to be safe, and to preserve systemic immune responses to both vaccines. Here we report on a secondary outcome of the trial investigating SARS-CoV-2-specific mucosal antibody responses. Anti-spike IgG and IgA levels in saliva were measured with in-house ELISAs. Concomitant administration of an influenza vaccine did not affect salivary anti-spike IgG positivity rates to Pfizer/BioNTech BNT162b2 (99.1 cf. 95.6%), or AstraZeneca ChAdOx1 (67.8% cf. 64.9%), at 3-weeks post-vaccination relative to placebo. Furthermore, saliva IgG positively correlated with serum titres highlighting the potential utility of saliva for assessing differences in immunogenicity in future vaccine studies. Mucosal IgA was not detected in response to either COVID-19 vaccine, reinforcing the need for novel vaccines capable of inducing sterilising immunity or otherwise reducing transmission. The trial is registered as ISRCTN 14391248.

The Effect of Dental Implants on Secretory Iga Level in Saliva

Background and aims: The host immune response is altered by a series of physiological and pathological factors such as age, gender, inflammation, surgery, and medications. This study was conducted to evaluate differences in salivary IgA (S-IgA) levels in individuals who underwent dental implant surgery and compare them to individuals who were not exposed to dental treatments. S-IgA levels were determined at least 3 months after implant installation. Methods: A total of 60 healthy individuals were included in the study; 30 participants received implant treatment (Implant Group) and were compared with 30 participants with no implant treatment as controls (Control Group). 1.5 ml of unstimulated saliva was obtained for all participants. The quantitative enzyme-linked immunosorbent assay (ELISA) technique was used for the measurement of salivary IgA levels. Results: The age range of the participants in the implant group was 38-62 years, with a mean age of 47.9 years; 18 (60%) were males and 12 (40%) were females. The age range of the study's controls was 38-59 years, with a mean age ± SD of 45.2 ± 5.2 years for 18 (60%) males and 12 (40%) females. The mean number of implants was 2.7 ± 0.83, and the mean period after implant placement was 19.2 ± 8.2 months. A low sIgA level (&lt; 250 μg/mL) was present in 10% of implant patients, but not in any cases in the control group. In contrast, only 6.7% of implant patients had this amount at a level greater than 351 μg/mL, compared to 53.3% in the control group. The mean ± SD for cases was 302.7 ± 36.8 g/mL versus 370.8 ± 59.2 μg/mL for controls, indicating that all normal distribution values were significantly lower in the implant patient group compared to higher values in healthy controls. Males had higher normal values across the board in both groups (cases and controls). Male dental implant patients' mean and standard deviation (312.2 ± 38.3 vs. 408.2 ± 42.2 µg/ml) showed a statistically significant decrease. Female dental implant patients' mean and standard deviation (287.3 30.6 vs. 314.7 ± 27.6 µg/ml) showed a statistically significant decrease. Overall, there was a significant decrease in the mean ±SD of dental implant patients (302.7 ± 36.8 µg/ml) versus the rising level in the total healthy control group (370.8 ± 36.8 µg/ml). The observed averages of sIgA for the presence of peri-implant mucositis in the two independent samples (yes, no) differed significantly by 60.7, with a 95% confidence interval of 41.1-80.3, and this finding is very significant (p&lt;0.0001). Conclusion: Salivary immunoglobulin A level values were significantly lower statistically in implant patients compared to the control group. The results, however, showed that there is a connection between lower sIgA levels in saliva and the development of pre-implant mucositis, meaning that low sIgA levels are risk factors for peri-implant mucositis or that peri-implant mucositis causes lower sIgA levels to be produced in mouth saliva.

Salivary immunoglobulin levels and periodontal indices in Brazilian children with and without type 1 diabetes.

This cross-sectional study evaluated the association between salivary immunoglobulins, plaque index, and gingival index in Brazilian children with and without type 1 diabetes mellitus (DM1). The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist for the reporting of observational studies was followed. The DM1 group had 38 children, and an equal number of volunteers matched by sex and age were recruited as controls. Clinical examination was performed for plaque index and gingival index determination. Non-stimulated whole saliva was collected. Concentrations of IgA, IgG, and IgM were determined by ELISA test. Data were tested by the Kolmogorov-Smirnov, Mann-Whitney, and Spearman tests and a multiple linear regression model (p<0.05) was performed. Gingival index was higher in the Control (DM1: 0.16±0.17; Control: 0.24±0.23, p=0.040). In DM1, there was a correlation between IgA and age (rho=0.371, p=0.024), IgM and IgG (rho=0.459, p=0.007), and IgM and gingival index (rho=0.394, p=0.014). In DM1, multiple linear regression showed that age (p=0.041; β=0.363), gingival index (p=0.041; β=0.398), and plaque index (p=0.008; β=-0.506) were good predictors of IgA levels in saliva. Thus, IgA was the only researched immunoglobulin that was directly associated with plaque and gingival indices in Brazilian children with DM1, but not in control subjects.

Differential levels of anti-Mycobacterium tuberculosis-specific IgAs in saliva of household contacts with latent tuberculosis infection.

Mucosal immunity is strongly elicited in early stages of many respiratory and enteric infections; however, its role in tuberculosis pathogenesis has been scarcely explored. We aimed to investigate Mycobacterium tuberculosis (Mtb) specific IgA levels in saliva in different stages of latent Tuberculosis Infection (TBI). A multiplex bead-based Luminex immunoassay was developed to detect specific IgA against 12 highly immunogenic Mtb antigens. A prospective cohort of household contacts (>14 years) of pulmonary TB cases was established in Santiago, Chile. Contacts were classified as Mtb-infected or not depending on serial interferon-γ release assay results. Saliva samples were collected and tested at baseline and at a 12-week follow-up. Mtb-specific IgA was detectable at all visits in all participants (n = 168), including the "non-Mtb infected" (n = 64). Significantly higher median levels of IgA were found in the "Mtb infected" compared to the uninfected for anti-lipoarabinomannan (LAM) (110 vs. 84.8 arbitrary units (AU), p < 0.001), anti-PstS1 (117 vs. 83 AU, p < 0.001), anti-Cell Membrane Fraction (CMF) (140 vs. 103 AU, p < 0.001) and anti-Culture Filtrate Proteins (CFP) (median 125 vs. 96 AU, p < 0.001), respectively. Nonetheless, the discriminatory performance of these specific mucosal IgA for TBI diagnosis was low. Saliva holds Mtb-specific IgA against several antigens with increased levels for anti-LAM, anti-PstS1, anti-CMF and anti-CFP found in household contacts with an established TBI. The role of these mucosal antibodies in TB pathogenesis, and their kinetics in different stages of Mtb infection merits further exploring.

Psycho-emotional portrait of primary school-age children with recurrent respiratory infections

Respiratory infections occupy a leading place in the structure of the population’s morbidity, especially among children. At the same time, recurrent respiratory infections (RRIs) impose the main burden on society and families. Most of the factors contributing to the manifestation of the RRI phenomenon have already been well-studied. However, the influence of psychological and emotional aspects on a child’s health has remained largely overlooked. Aim. to study the psychological characteristics of children aged 5–7 years in comparison to episodically ill peers and their correlation with local immunity indicators. Materials and Methods. The study involved 80 children, with 60 in the main group (children with recurrent respiratory infections) and 20 in the control group (episodically ill children). For psychological testing (psychometrics), the following methods were used: Blob Tree test (P. Wilson) to determine motivation and adaptation of children in a group setting. The projective „Family Sociogram‟ test (E.G. Aidemiller) to determine the place of the subject in the system of interpersonal relationships and to assess the nature of communication within the family. A modified version of A. Etkind’s Color Relations Test was used to determine individual typological personality characteristics and attitudes towards significant people and the surrounding environment on both a conscious and partially unconscious level. Clinical laboratory examination included measuring levels of secretory IgA and lysozyme in unstimulated saliva. Results. When analyzing the data obtained, a statistically significant difference was found between the results of children in the main and control groups. Conclusions. During color selection, children with RRIs more often associated themselves with the color red (40.7 %), their mothers with purple (40.7 %), and kindergarten or school with yellow (29.7 %) compared to episodically ill peers (p &lt; 0.05). Children with RRIs in the „Family Sociogram‟ test more often than episodically ill peers demonstrated reduced self-esteem (73 % vs. 30 %, p = 0.038). In the Blob Tree test, children with RRIs differ in their first choice (current position in the group) from episodically ill peers (p &lt; 0.0001). The level of sIgA and lysozyme in saliva in the group of children with RRIs correlates with the sensory choice of color for the mother (p &lt; 0.0001).

Immunoglobulin A response to SARS-CoV-2-N-protein potentially persists in oral fluids of patients with periodontitis six months after mRNA vaccine administration

Few studies have investigated the mucosal immune response after BNT162b2-booster vaccination in individuals with periodontitis. In this study, we evaluated the persistence of IgA anti-SARS-CoV-2-N-protein in saliva and gingival crevicular fluid (GCF) of patients with periodontitis for at least six months post BNT162b2 vaccine booster. We included patients with moderate (n = 7) and severe (n = 7) periodontitis and participants without periodontitis (n = 7) as controls. The Bradford method measured the protein concentrations in the samples, and an enzyme-linked immunosorbent assay of the SARS-CoV-2 N protein was performed to analyze the targeted IgA level. For the tested SARS-CoV-2 antigen (N-protein), IgA levels in saliva and GCF showed a strong and significant correlation. Therefore, in patients with moderate or severe periodontitis, saliva and GCF can provide information regarding the IgA response against SARS-CoV-2-N-protein. The neutralizing activity of IgA against SARS-CoV-2 was not investigated in this study, necessitating further research.

CATION COMPOSITION OF ORAL SECRETION IN PRIMARY SCHOOL-AGED CHILDREN

SUMMARY. Recurrent respiratory infections (RRIs) currently have the greatest medical and social burden among infectious diseases worldwide, with the highest prevalence and incidence rates of acute respiratory infections in children. Recent studies indicate the role of inadequate immune response and the development of recurrent acute respiratory infections (ARI) in children due to deficiencies in essential trace elements in the body, which are crucial for the proper functioning of physical barriers and the immune system. The hypothesis of our study assumed that, considering the recurrence of at least 6 episodes of ARI per year, children with RRIs may have changes in salivary ion levels, which could serve as a basis for local immune suppression of the upper respiratory mucosa. The aim – to investigate the levels of metals in the saliva of children of primary school age with recurrent respiratory infections in comparison with episodically ill peers and establish the relationship of these changes with the state of local immunity. Material and Methods. In the actual study, 40 children participated, with 30 of them (the main group) being children with recurrent respiratory infections and 10 other children who had episodic illnesses were assigned to the control group. The levels of metal cations in the saliva were examined using inductively coupled plasma atomic emission spectrometry, including essential metals such as copper, manganese, zinc, calcium, cobalt, potassium, magnesium, sodium, phosphorus, selenium, iron, chromium, and sulfur. Additionally, levels of conditionally essential metals like lithium, nickel, and boron were measured. The levels of secretory IgA and lysozyme in saliva were determined using the enzyme-linked immunosorbent assay method. Results. The main group was not homogeneous; therefore, we divided it into two clusters. Respondents in one cluster had significantly lower relative levels of essential ion content in saliva. Specifically, calcium was lower in 64 % (p=0.003), copper in 76.5 % (p=0.001), manganese in 41.1 % (p=0.008), magnesium in 64 % (p=0.02), and zinc in 58.8 % (p=0.027). This fact can be explained by their increased losses due to frequent inflammatory processes in the upper respiratory tract, resulting in higher daily replenishment needs compared to their peers. Correlation analysis revealed a connection between illness incidence and the levels of copper (p=0.008), sodium (p=0.00005), and phosphorus (p=0.028), indicating potential associations between saliva metal profiles and the frequency of ARI in children with RRIs. The presence of dental caries correlated with lithium (p=0.02), copper (p=0.032), and nickel levels (p=0.037). Integral indicators of local immunity, such as lysozyme and secretory IgA, exhibited correlations with metal levels in saliva (Li, Cu, Ni, Na, Co, P, Zn), confirming the hypothesis of their role in regulating immune reactions in the oral cavity. Conclusions. Cluster analysis of the metal profiles of the group of children with RRI shows its heterogeneity, 43 % of representatives of this cohort had significantly lower levels of calcium (p=0.003), copper (p=0.001), manganese (p=0.008), magnesium (p=0.02) and zinc (p=0.027) than the control group. Which may indicate the presence of deficient conditions in some children with PRI as a result of the increased need for their recovery. The presence of caries, the level of SIgA, lysozyme (clinical indicators of local immunity of the oral cavity) have certain relationships with the levels of essential and conditionally essential levels of salivary metals (Li, Cu, Ni, Na, Co, P, Zn), which indicates the benefit of the connection between the metal profile of saliva and the state of local immunity.

Correlation between salivary immunoglobulin A and interleukin-1beta in smokers with dental caries.

Introduction. Dental caries is one of the most common infectious diseases of the oral cavity, and is an inflammatory disease caused by several factors. Interleukin-1β (IL-1β) is a major mediator of acute inflammation and essential for the development of specific immune responses. The objective of this study was to assess the levels of secretory IgA (s-IgA) and IL-1β in the saliva of smokers with dental caries, and to discover the correlation between these parameters and dental caries. Methods. Saliva samples were collected from 30 smokers, age range 21-70 years, with dental caries, in addition to 18 healthy non-smoker volunteers, age range 21-65 years. s-IgA and IL-1β levels in the saliva samples were estimated by enzyme-linked immunosorbent assay (ELISA). Results. The mean saliva IgA levels between smokers with dental caries group and healthy subjects were not significantly different (p=0.077), while the saliva levels of IL-1β were higher in the smokers in dental caries group, with a significant difference of p<0.05. No significant associations were found between s-IgA and IL-1β levels, and other parameters such as age, sex, body mass index (BMI) and C-reactive protein (CRP) (p>0.05). There were highly positive associations and significant differences between IL-1β and CRP levels in the two groups under the study (p=0.006). Conclusions. Our study revealed a significant increase in IL-1β levels in saliva of smokers with dental caries, and a positive association between IL-1β levels and caries disease. There is no significant relationship between elevated IL-1β levels and s-IgA in smokers with dental caries.

Correlation between salivary immunoglobulin A and interleukin-1beta in smokers with dental caries

Introduction. Dental caries is one of the most common infectious diseases of the oral cavity, and is an inflammatory disease caused by several factors. Interleukin-1β (IL-1β) is a major mediator of acute inflammation and essential for the development of specific immune responses. The objective of this study was to assess the levels of secretory IgA (s-IgA) and IL-1β in the saliva of smokers with dental caries, and to discover the correlation between these parameters and dental caries. Methods. Saliva samples were collected from 30 smokers, age range 21–70 years, with dental caries, in addition to 18 healthy non-smoker volunteers, age range 21–65 years. s-IgA and IL-1β levels in the saliva samples were estimated by enzyme-linked immunosorbent assay (ELISA). Results. The mean saliva IgA levels between smokers with dental caries group and healthy subjects were not significantly different (p=0.077), while the saliva levels of IL-1β were higher in the smokers with dental caries group, with a significant difference of p&lt;0.05. No significant associations were found between s-IgA and IL-1β levels, and other parameters such as age, sex, body mass index (BMI) and C-reactive protein (CRP) (p&gt;0.05). There were highly positive associations and significant differences between IL-1β and CRP levels in the two groups under the study (p=0.006). Conclusions. Our study revealed a significant increase in IL-1β levels in saliva of smokers with dental caries, and a positive association between IL-1β levels and caries disease. There is no significant relationship between elevated IL-1β levels and s-IgA in smokers with dental caries.

Immunological and Bacteriological Monitoring of Periodontal Tissue in Pregnancy

We determine periodontal pathogens in periodontal pockets from pregnant women with periodontitis and associate it to the C reactive protein (CRP), nitrates, immunoglobulin A and G (Ig A and G), and myeloperoxidase (MPO) levels in saliva to identify some biomarkers as tools to predict the periodontal status from pregnant. The samples were obtained from periodontal pockets and saliva from 100 pregnant women (PW) and 50 non-pregnant women (NPW). Every patient was evaluated by: 1) probing depth (PD) and loss of clinical attachment level (CAL); 2) in saliva; CRP, MPO, Ig A and G) and nitrite concentrations, 3) in periodontal pockets: P.gingivalis, T.forsythia, T.denticola, P.intermedia, A.actinomycetemcomitans. InfoStat/P 2008 software was used with a p-value &lt;0.05. Clinical parameters showed stages I and II of PD in both groups. P.intermedia and A.actinomycetemcomitans were observed only in periodontal pockets from PW. The CAL was higher in pregnant of the 3rd trimester than in the other stages and was associated with low levels of IgA and the presence of P.intermedia and T. forsythia in the same trimester. The levels of IgA in saliva would reflect the immunological situation in pregnant women. This could be used to monitor the immune status of the gingival tissues during pregnancy.

Longevity and neutralisation activity of secretory IgA following SARS-CoV-2 infection

The mucosal barrier is a primary defence against inhaled pathogens, comprising secretory antibodies which have the potential to block viral entry and neutralise infection. There is an ongoing need for greater understanding of the mucosal immunity to SARS-CoV-2 infection. In this study, we investigated mucosal IgA through non-invasive saliva sampling of healthcare workers. A total of 551 saliva samples were collected from staff at Great Ormond Street Children’s Hospital who previously tested positive for COVID-19. Participant metadata included age, gender, ethnicity and symptoms. IgA titres were measured by ELISA against viral antigens spike protein, nucleocapsid protein, and spike receptor-binding domain. SARS-CoV-2 neutralisation was measured using a VERO E6 cell culture infection assay. We found that approximately 30% of saliva samples contained detectable IgA specific for at least one of the SARS-CoV-2 antigens. IgA levels in saliva decreased with the time post-infection, and were largely undetectable after six months. IgA titres specific to SARS-CoV-2 were lowest in participants over 60 years old. Specific saliva samples were identified which effectively neutralised SARS-CoV-2 virus infection of epithelial cells. Our results suggest secretory IgA specific to SARS-CoV-2 can be detected in saliva following infection, an accessible sample type for testing, although titres decreased over time. Some saliva samples were able to neutralise SARS-CoV-2 infectivity against cultured epithelial cells. This data could be used to assess the risk of re-infection with SARS-CoV-2, as well as accelerate efforts to develop effective mucosal vaccination with longer lasting protection.

Analysis of Saliva and Gingival Crevicular Fluid Immunoglobulin A in Adults Having Different Caries Status

Objective: The aim of the study was to compare the salivary IgA and gingival crevicular fluid IgA levels in caries active and caries free subjects. Methods: The study was carried out on 40 subjects divided into two groups, Group I caries free, (DMFT =0) and Group II caries active, (DMFT &amp;gt;10). Saliva and gingival crevicular fluid samples were obtained and plaque index, gingival index, gingival crevicular fluid volume and salivary flow rate were determined. The levels of S. mutans and lactobacillus were determined by culture. IgA concentrations of saliva and gingival crevicular fluid samples were determined using the ELISA. Data were analyzed using the Mann-Whitney U and χ2 tests (α = 0.05). Results: Gingival crevicular fluid volume, plaque index and gingival index values of group II were significantly higher than group I (p&amp;lt; 0.05). Although lactobacillus counts of group II were higher than group I, no statistically significant differences were observed for microorganism counts (p&amp;gt;0.05). Salivary flow rate, gingival crevicular fluid-IgA and saliva-IgA levels were no statistically significant between the groups (p&amp;gt;0.05). Conclusion: The present study showed that microorganism counts in the saliva did not by themselves influence the DMFT index. There is no dependence between secretory immunity and dental caries in subjects.

Human Physiological Responses to a Single Deep Helium-Oxygen Diving.

Objective: The objective of this study was to explore whether a single deep helium-oxygen (heliox) dive affects physiological function.Methods: A total of 40 male divers performed an open-water heliox dive to 80 m of seawater (msw). The total diving time was 280 min, and the breathing helium-oxygen time was 20 min. Before and after the dive, blood and saliva samples were collected, and blood cell counts, cardiac damage, oxidative stress, vascular endothelial activation, and hormonal biomarkers were assayed.Results: An 80 msw heliox dive induced a significant increase in the percentage of granulocytes (GR %), whereas the percentage of lymphocytes (LYM %), percentage of intermediate cells (MID %), red blood cell number (RBC), hematocrit (hCT), and platelets (PLT) decreased. During the dive, concentrations of creatine kinase (CK), a myocardial-specific isoenzyme of creatine kinase (CK-MB) in serum and amylase alpha 1 (AMY1), and testosterone levels in saliva increased, in contrast, IgA levels in saliva decreased. Diving caused a significant increase in serum glutathione (GSH) levels and reduced vascular cell adhesion molecule-1 (VCAM-1) levels but had no effect on malondialdehyde (MDA) and endothelin-1 (ET-1) levels.Conclusion: A single 80 msw heliox dive activates the endothelium, causes skeletal-muscle damage, and induces oxidative stress and physiological stress responses, as reflected in changes in biomarker concentrations.

Kinetics of humoral deficiency in CART19-treated children and young adults with acute lymphoblastic leukaemia

CD19-CAR T-cell therapy (CART19) causes B-cell aplasia (BCA) and dysgammaglobulinemia but there is a lack of information about the degree of its secondary immunodeficiency. We conducted a prospective study in children and young adults with acute lymphoblastic leukaemia treated with CART19, analysing the kinetics of BCA and dysgammaglobulinemia during therapy, as well as the B-cell reconstitution in those with CART19 loss. Thirty-four patients were included (14 female) with a median age at CART19 infusion of 8.7 years (2.9–24.9). Median follow-up after infusion was 7.1 months (0.5–42). BCA was observed 7 days after infusion (3–8), with persistence at 24 months in 60% of patients. All patients developed a progressive decrease in IgM and IgA: 71% had undetectable IgM levels at 71 days (41–99) and 13% undetectable IgA levels at 185 days (11–308). Three of 12 patients had protective levels of IgA in saliva. In two of three patients who lost CART19, persistent B-cell dysfunction was observed. No severe infections occurred. In conclusion, BCA occurs soon after CART19 infusion, with a progressive decrease in IgM and IgA, and with less impairment of IgA, suggesting the possibility of an immune reservoir. A persistent B-cell dysfunction might persist after CART19 loss in this population.

Evaluation of the immune response in conventionally weaned pigs infected with porcine deltacoronavirus.

Although porcine deltacoronavirus (PDCoV) is a significant pandemic threat in the swine population and has caused significant economic losses, information regarding the immune response in conventionally weaned pigs infected with PDCoV is scarce. Hence, the immune response in conventionally weaned pigs infected with PDCoV was assessed after challenge and rechallenge. After the first challenge, obvious diarrhea and viral shedding developed successively in all pigs in the four inoculation dose groups from 3 to 14 days postinfection (dpi), and all pigs recovered (no clinical symptoms or viral shedding) by 21 dpi. All pigs in the four groups exhibited significantly increased PDCoV-specific IgG, IgA and virus-neutralizing (VN) antibody (Ab) titers and IFN-γ levels in the serum after the first challenge. All pigs were completely protected against rechallenge at 21 dpi. The serum levels of PDCoV-specific IgG, IgA, and VN Abs increased further after rechallenge. Notably, the IFN-γ level declined continuously after 7 dpi. In addition, the levels of PDCoV-specific IgG, IgA and VN Abs in saliva increased significantly after rechallenge and correlated well with the serum Ab titers. Furthermore, the appearance of clinical symptoms of PDCoV infection in conventionally weaned pigs was delayed with reduced inoculation doses. In summary, the data presented here offer important reference information for future PDCoV animal infection and vaccine-induced immunoprotection experiments.

Effect of salivary secretion with mouthguard use on seasonal allergic rhinitis symptom improvement

ObjectivesIt was shown that mucosal immunity via salivary IgA may be related to the improvement of seasonal allergic rhinitis (SAR) symptoms, and improvement of SAR symptoms through saliva flow increase has been reported in patients using mouthguard (MG) in dental treatment. The purpose of this study was to analyze the effect of MG use on SAR symptom improvement and to clarify the role of saliva on SAR symptom development. MethodsWe recruited patients from the Kanagawa Dental University Hospital including 38 and 8 patients with SAR and non-SAR symptoms during two seasons from March 2017 to April 2018. We analyzed the saliva flow rate pre- and post-MG use and measured the amount of IgA and IgG4 in the saliva. We assessed the correlation between SAR symptoms and MG use. SAR symptoms were examined according to a specific clinical score. ResultsIt was revealed that salivary IgA concentration was significantly lower in SAR patients than in controls. SAR symptoms significantly improved with MG use. The saliva flow rate and IgA levels significantly increased with MG use, although the IgG4 levels did not change. ConclusionsMG use may be beneficial for improving the symptoms of SAR patients by increasing the IgA levels. Trial registrationUniversity Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR: UMIN000026428) on 6thMarch 2017.

Norovirus-specific mucosal antibodies correlate to systemic antibodies and block norovirus virus-like particles binding to histo-blood group antigens

The best acknowledged correlate of protection from norovirus (NoV) infection is the ability of serum antibodies to block binding of NoV virus-like particles (VLPs) to histo-blood group antigens (HBGAs). We investigated mucosal NoV-specific antibody levels in adult volunteers and used saliva from a single donor to determine whether purified saliva antibodies confer blocking. NoV-specific IgG and IgA levels in saliva and plasma samples were measured against four NoV genotype VLPs. NoV-specific IgG and IgA titers in saliva and plasma samples correlated significantly. Antibodies were detected against all VLPs with the highest level of antibodies directed against ancestral GII.4 99 genotype. Affinity chromatography purified salivary IgA and IgG blocked binding of GII.4 99 VLPs to HBGAs. Saliva sampling is a non-invasive alternative to blood drawing and an excellent biological fluid to study NoV-specific immune responses. Mucosal anti-NoV antibodies block binding of NoV VLPs to HBGAs, and may therefore be protective.

Influence of the physiological stage of Blackbelly sheep on immunological behaviour against gastrointestinal nematodes

The influence of the physiological stage of a Blackbelly flock against natural infection by gastrointestinal parasitic nematodes (GIN) was investigated. Data on serum and saliva IgA levels and peripheral cellular immune response were recorded in 51 sheep for 6 months. The flock was divided based on their physiological stage as follows: a) pregnant ewes, b) lactating ewes, c) non-pregnant ewes, d) pre-weaning lambs, e) growing lambs and f) replacement sheep. Additionally, sheep were classified based on the parasite infection as stabled or grazing management system as follows: g) non-infected stabled sheep, h) infected and stabled sheep and i) infected grazing sheep. Faeces and blood samples were collected every fifteen days. The percentage of packed cell volume (PCV), plasma protein, (PP) and leucocyte differential counts (LDC) were recorded. Likewise, serum and saliva IgA levels were measured by the indirect ELISA technique. The number of GIN eggs excreted per g of faeces (EPG) was also determined using the McMaster technique. Data were analysed using the SAS program to identify fixed effect of physiological stages, infection time and interactions. Results showed high EPG values in stabled lactating ewes (2764) and in growing lambs (2950–4550 EPG). Pregnant ewes had higher PCV values (27%) than lactating ewes (23.5%). Infected lambs showed low PCV values (28.5%) and high PP values (5.9 g/dL) compared with non-infected lambs (31% PCV and 5.6 g/dL PP). The two most abundant GIN species identified were Haemonchus contortus (91%) and Trichostrongylus colubriformis (81%). Pregnant and non-pregnant ewes showed 29% and <20% of IgA values, respectively. High EPG, low IgA and eosinophils counts were observed until 180 days of age in infected lambs. In conclusion, the group of infected lactating ewes and lambs showed susceptibility to GIN than the other groups, including the pregnant ewes.

A Comparative Evaluation of Serum and Salivary Total Proteins and Immunoglobulins in Patients with Hepatitis A and Healthy Subjects

Assessment of changes in total proteins level, serum and saliva IgG and IgA levels, serum IgM level, serum and saliva IgA/IgG ratio. The study was conducted on a group of 40 subjects, divided into 2 lots: the first lot consisting of 20 healthy individuals and the second consisting of 20 patients with hepatitis with hepatitis A virus (HAV). The levels of total proteins, serum and saliva IgG and IgA, serum IgM and serum and saliva IgA/IgG ratio have higher values in patients with hepatitis A, in comparison to healthy subjects, without necessarily exceeding the maximum admitted value. The results are significant from a statistical point of view. Due to the sensitivity and specificity of salivary anti-HAV IgM and IgG in patients with acute hepatitis A, compared with healthy subjects, there is a possibility of using salivary immunological tests instead of serum tests for the diagnosis and epidemiological study of HAV infection.