Salivary IgA Research Articles

Salivary Antibody Responses to Potentially Waterborne and Environmentally Transmitted Infections Among Two Tribal Nations in the Southwest United States.

Tribal Nations disproportionately lack access to safe drinking water and can be adversely affected by other water quality and environmental concerns. Such conditions could lead to an increase in the transmission of waterborne, environmental and hygiene related infections. We collected saliva samples from attendees at two Tribal Nation annual festivals and tested them for salivary immunoglobulin G (IgG) responses to selected common infections using an in-house multiplex immunoassay. Antibody responses were compared to responses from a previously conducted study in the midwestern United States. We collected and tested 531 samples from Tribal Nation sites and used data on 453 previously analyzed samples from the Midwest site. Logistic and linear regression models were used to model a binary classification of seropositivity and the intensity of the antibody response, respectively. Seroprevalence of chronic infections (Helicobacter pylori and Toxoplasma gondii) were generally consistent with estimates from population-based studies. Compared to the Midwest site, one of the Tribal Nation sites had consistently higher median antibody responses to several noroviruses. The Tribal Nation sites had a lower seroprevalence of hepatitis E virus antibodies. At the Tribal Nation sites, farm residents had higher antibody responses to Cryptosporidium spp., bottled water consumption was associated with lower responses to Cryptosporidium spp., animal contact was associated with T. gondii seropositivity, and recent diarrhea was associated with higher norovirus antibody responses. Helicobacter pylori seropositivity was associated with reduced odds of reporting allergies. This study demonstrated the application of a multiplex salivary immunoassay in Tribal Nations to provide insights regarding selected common pathogens which are transmitted through different transmission pathways including person-to-person contacts, contaminated food, soil and drinking water.

A Preliminary Study: Neurological, Immunological, and Endocrine Aspects of Healthcare Workers without Burnout Syndrome

Summary: Healthcare workers are vulnerable to stress and burnout, which can affect the Hypothalamus-Hypophysis Axis (HHA) pathway. This pathway can involve psychological, neurological, immunological, and endocrine aspects. These can be evaluated using the Maslach Burnout Inventory Human Services Survey (MBI-HSS), a heart rate variability tool, laboratory tests using salivary immunoglobulin-A (sIg-A), T-cell regulator (TC), endorphins, and salivary cortisol (SC) levels. Purpose: This study aimed to describe the neurological, immunological, and endocrine aspects of healthcare workers without burnout syndrome Methods: A quantitative descriptive study was conducted to describe the psychological, neurological, immunological, and endocrine aspects of healthcare workers. Purposive sampling was used. Findings: Sixty-two participants took the MBI-HSS, and 30 participants without burnout were selected. There were 28 nurses, with an average age of 28 years old. About 93,3% of the participants were female, 80% worked at the emergency department, and 60% had over three years of working experience. From HRV test results, 14 participants were within the normal range (50-100 ms). The average -endorphine serum level is 481,93 pg/ml. Around 60% of participants showed normal SC levels, and 40% showed low SC levels (mean 5,72 ng/ml). Around 90% showed normal sIg-A and 10% high sIg-A levels (mean 501,6 g/ml). The average TC was 23% CD4, with 8,1% CD25 and 6,4% CD127. Conclusion: This study found that average healthcare workers showed normal HRV, endorphins, SC, sIg-A, and T cell regulators, representing neurological, immunological, and endocrine aspects. Therefore, further study is needed to determine the impact of burnout syndrome on these aspects.

The Role of Biomarkers in Monitoring Chronic Fatigue Among Male Professional Team Athletes: A Systematic Review.

This systematic review synthesizes evidence on biomarker responses to physiological loads in professional male team sport athletes, providing insights into induced fatigue states. Structured searches across major databases yielded 28 studies examining various biomarkers in elite team sport players. Studies evaluated muscle damage markers, anabolic/catabolic hormones reflecting metabolic strain, inflammatory markers indicating immune activity and tissue damage, immunological markers tied to infection risk, and oxidative stress markers showing redox imbalances from excessive physiological load. Responses were examined in official matches and training across competitive seasons. The evidence shows that professional team sports induce significant alterations in all studied biomarkers, reflecting measurable physiological strain, muscle damage, oxidative stress, inflammation, and immunosuppression during intensive exercise. These effects tend to be larger and more prolonged after official matches compared to training. Reported recovery time courses range from 24-h to several days post-exercise. Monitoring biomarkers enables quantifying cumulative fatigue and physiological adaptations to training/competition loads, helping to optimize performance while mitigating injury and overtraining. Key biomarkers include creatine kinase, testosterone, cortisol, testosterone/cortisol ratio, salivary immunoglobulin-A, and markers of inflammation and oxidative stress. Further research should extend biomarker monitoring to cover psychological stress and affective states alongside physiological metrics for deeper insight into athlete wellness and readiness.

Supplementation with whey peptide rich in β-lactolin improves trait anxiety and subjective stress in healthy adults: a randomized, double-blind, placebo-controlled study.

Mental disorders have become one of the most burdensome health concerns. We have previously demonstrated that whey-derived β-lactolin (glycine-thereonine-tryptophan-tyrosine tetrapeptide) activates dopaminergic systems and improves psychiatric function in rodents. However, the effects of β-lactolin on human mood states have not been investigated. This randomized, double-blind, placebo-controlled study aimed to evaluate the effects of supplementation with β-lactolin-rich whey peptide on human mood states. Sixty healthy adults (aged 45-64 years) with relatively low psychological health were randomly allocated to receive either whey peptide (containing β-lactolin 1.6mg/day) or placebo for 6 weeks. Mood states (primary outcomes) were evaluated using self-reporting questionnaires. Health-related quality of life (QOL), salivary stress marker and lipid mediator levels were evaluated as secondary outcomes. Compared with placebo, supplementation with β-lactolin improved changes in trait anxiety (p = 0.046), as assessed using the state-trait anxiety inventory, and in subjective stress (p = 0.043), as assessed using the Perceived Stress Scale. In the assessment of QOL, changes in the vitality subscale and mental health summary score of the 36-Item Short-Form Health Survey were improved in the β-lactolin group. The levels of salivary immunoglobulin A were significantly higher in the β-lactolin group. In a subgroup analysis by median age (54.5 years), subjective stress and salivary prostaglandin levels were significantly decreased by β-lactolin supplementation in the 45-54 -year-old subgroup. In conclusion, supplementation with β-lactolin improves trait anxiety, subjective stress, and psychological QOL, which may be associated with immunologic responses detected via salivary analysis.

Is There a Role for Immunostimulant Bacterial Lysates in the Management of Respiratory Tract Infection?

Bacterial Lysates are immunostimulants clinically prescribed for the prevention of respiratory tract infections (RTIs). It has been shown that Bacterial Lysates upregulate the immune system, acting both on innate and adaptive reactions. In fact, there are demonstrations of their efficacy in restoring the integrity and immune function of epithelial barriers, activating ILC3 and dendritic cells with an enhanced Th1 response, and producing serum IgG and serum and salivary IgA specific to the administered bacterial antigens. The activated immune system also protects against other bacteria and viruses due to a trained immunity effect. Most studies show that the number of RTIs and their severity decrease in Bacterial Lysates-pretreated patients, without relevant side effects. The Bacterial Lysates treatment, in addition to reducing the number of RTIs, also prevents the deterioration of the underlying disease (i.e., COPD) induced by repeated infections. Despite these positive data, the most recent meta-analyses evidence the weakness of the studies performed, which are of low quality and have an inadequate number of patients, some of which were non-randomized while others were without a control group or were performed contemporarily in different clinical conditions or with different ages. The high heterogeneity of the studies does not allow us to state Bacterial Lysates' effectiveness in preventing RTIs with sufficient certainty. To completely define their indications, double-blind, placebo-controlled, multicenter, randomized clinical trials should be performed for each product and for each indication. The study population should be adequate for each indication. For this purpose, an adequate run-in phase will be necessary.

Salivary polyreactive antibodies and Haemophilus influenzae are associated with respiratory infection severity in young children with recurrent respiratory infections.

Recurrent respiratory tract infections (rRTIs) are a common reason for immunodiagnostic testing in children, which relies on serum antibody level measurements. However, because RTIs predominantly affect the respiratory mucosa, serum antibodies may inaccurately reflect local immune defences. We investigated antibody responses in saliva and their interplay with the respiratory microbiota in relation to RTI severity and burden in young children with rRTIs. We conducted a prospective cohort study including 100 children aged <10 years with rRTIs, their family members and healthy healthcare professionals. Total and polyreactive antibody concentrations were determined in serum and saliva (ELISA); respiratory microbiota composition (16S rRNA sequencing) and respiratory viruses (quantitative PCR) were characterised in nasopharyngeal swabs. Proteomic analysis (Olink) was performed on saliva and serum samples. RTI symptoms were monitored with a daily mobile phone application and assessed using latent class analysis and negative binomial mixed models. Serum antibody levels were not associated with RTI severity. Strikingly, 28% of salivary antibodies and only 2% of serum antibodies displayed polyreactivity (p<0.001). Salivary polyreactive IgA was negatively associated with recurrent lower RTIs (adjusted OR 0.80, 95% CI 0.67-0.94) and detection of multiple respiratory viruses (adjusted OR 0.76, 95% CI 0.61-0.96). Haemophilus influenzae abundance was positively associated with RTI symptom burden (regression coefficient 0.05, 95% CI 0.02-0.08). These results highlight the importance of mucosal immunity in RTI severity and burden, and suggest that the level of salivary polyreactive IgA and H. influenzae abundance may serve as indicators of infection severity and burden in young children with rRTIs.

PSV-10 Vaccination of beef cattle to reduce enteric methane emissions

Abstract Livestock methane (CH4) emissions total over 3 billion tonnes per year of carbon dioxide equivalents (CO2e) and are responsible for approximately 6% of total annual greenhouse gas emissions. The contribution of livestock CH4 emissions are only to be exacerbated as the global demand for meat and dairy products increases. Greater than 75% of livestock CH4 emissions are generated in dispersed production environments (e.g., cow-calf and stocker segments), which are not addressable by methane mitigation strategies requiring constant inputs. Thus, strategies that fit into standard agronomic practices, in particular dispersed production environments, are urgently needed to address the increasing carbon footprint associated with livestock production. Methane-reducing vaccines are a promising solution for addressing this need, due to their longevity of action, low cost, and ease of integration into standard agronomic practices, which could lower the barrier for adoption. Thus, this study aimed to assess the effects of a prototype vaccine on total and antigen-specific immune response, CH4 yield, and average daily gain (ADG) in cattle. Angus crossbred steers [n = 20; initial body weight (BW) = 537 ± 15 kg) fed on a high-forage diet were randomly assigned to either placebo- or vaccine-treated groups blocked by BW, breed, and feed intake. Steers were subcutaneously inoculated (2 mL dose) in the anterior region of the neck. Blood and saliva samples were collected, and total sera and salivary immunoglobulin (Ig) G and IgA were quantified using ELISA (Bethyl laboratories, Montgomery, TX). Antigen-specific sera IgG was measured using ELISA. Daily CH4 emissions and dry matter intake (DMI) were measured using GreenFeed systems (C-Lock Inc. Rapid City, SD) and GrowSafe feed bunks (Vytelle, Lenexa, KS), respectively. Body weights were recorded bi-weekly. Total sera IgA and IgG did not differ between the placebo-treated and vaccinated steers (P = 0.584 and P = 0.425, respectively), nor did total salivary IgA and IgG (P = 0.577 and P = 0.548, respectively). However, antigen-specific sera IgG did significantly increase following booster vaccination in the vaccinated steers, as compared with placebo-treated steers (d 0 vs. d 28; P &amp;lt; 0.001). CH4 yield was significantly reduced in vaccinated steers following booster vaccination despite significantly increasing in placebo-treated steers over the same period (P = 0.002). This reduction in CH4 yield was not associated with a reduction in DMI nor ADG (P = 0.181 and P = 0.314, respectively), suggesting that vaccination did not negatively affect treated animals. These findings underscore the potential of vaccine-based solutions to mitigate the environmental impact of livestock CH4 emissions, especially from dispersed production environments where current options for mitigation strategies are limited.

Salivary immune responses after COVID-19 vaccination.

mRNA-based COVID-19 vaccines have played a critical role in reducing severe outcomes of COVID-19. Humoral immune responses against SARS-CoV-2 after vaccination have been extensively studied in blood; however, limited information is available on the presence and duration of SARS-CoV-2 specific antibodies in saliva and other mucosal fluids. Saliva offers a non-invasive sampling method that may also provide a better understanding of mucosal immunity at sites where the virus enters the body. Our objective was to evaluate the salivary immune response after vaccination with the COVID-19 Moderna mRNA-1273 vaccine. Two hundred three staff members of the U.S. Centers for Disease Control and Prevention were enrolled prior to receiving their first dose of the mRNA-1273 vaccine. Participants were asked to self-collect 6 saliva specimens at days 0 (prior to first dose), 14, 28 (prior to second dose), 42, and 56 using a SalivaBio saliva collection device. Saliva specimens were tested for anti-spike protein SARS-CoV-2 specific IgA and IgG enzyme immunoassays. Overall, SARS-CoV-2-specific salivary IgA titers peaked 2 weeks after each vaccine dose, followed by a sharp decrease during the following weeks. In contrast to IgA titers, IgG antibody titers increased substantially 2 weeks after the first vaccine dose, peaked 2 weeks after the second dose and persisted at an elevated level until at least 8 weeks after the first vaccine dose. Additionally, no significant differences in IgA/IgG titers were observed based on age, sex, or race/ethnicity. All participants mounted salivary IgA and IgG immune responses against SARS-CoV-2 after receiving the mRNA-1273 COVID-19 vaccine. Because of the limited follow-up time for this study, more data are needed to assess the antibody levels beyond 2 months after the first dose. Our results confirm the potential utility of saliva in assessing immune responses elicited by immunization and possibly by infection.

Psychobiological responses to choir singing and creative arts activities in children and adolescents with mental disorders: results of apilot study.

Children and adolescents living with mental health problems often experience stress and poor mood states, which may influence their quality of life and well-being. Arts interventions may improve mood and well-being and reduce physiological stress in this vulnerable population. Acohort of patients in child and adolescent psychiatry (N = 42; age range: 12-18years) participated in one of four arts activities including choir singing (n = 11), textile design (n = 9), drama (n = 16), and clownery (n = 6). They were led by professional artists and delivered through five consecutive 90-min daily afternoon sessions over the course of 1week. Questionnaires of mood and saliva samples before and after each session served to assess short-term psychobiological changes. In addition, patients reported their quality of life and well-being at the beginning and at the end of the 1‑week program. Results showed that alertness was significantly enhanced after textile design (∆post-pre = 4.08, 95% CI [0.77, 7.39]) and after singing (∆post-pre = 2.20, 95% CI [-0.55, 4.94]). Moreover, mood tended to be positively affected by textile design (∆post-pre = 2.89, 95% CI [-0.39, 6.18]). Quality of life increased significantly after singing (∆post-pre = 5.49, 95% CI [1.05, 9.92]). Arts participation except singing was associated with significant reductions in salivary cortisol (sCort) (textile design ∆post-pre = -0.81 ng/mL, 95% CI [-1.48, -0.14]; drama ∆post-pre = -0.76 ng/mL, 95% CI [-1.28, -0.24]; clownery ∆post-pre = -0.74 ng/mL, 95% CI [-1.47, -0.01]). No significant changes were observed for well-being over the whole program and salivary immunoglobulinA (sIgA) after any of the arts activities. These results suggest that arts participation can improve mood state and reduce stress in young people with mental disorders, but there is aneed for further studies.

The impact of malnutrition on dental health of 12-year-old children: a study on permanent teeth caries, cariogenic bacteria and salivary IgA.

Malnutrition in children is epidemic in developing countries. Several health issues and consequences are believed to develop due to this phenomenon. Children's oral health is also affected by malnutrition. The main aspects of oral health status are caries experience, the existence of cariogenic bacteria, and salivary immunoglobulin A.

Comparison of Glucose and Immunoglobulin a Levels in Serum and Saliva of Patients with Type 1 and Type 2 Diabetes

Introduction: The monitoring and management of blood glucose levels are of significant importance in individuals diagnosed with diabetes mellitus. Accordingly, the objective of this study was to examine the potential of a non-invasive approach for the diagnosis and management of diabetes, through the measurement of glucose concentration and salivary IgA, and a comparison with fasting glucose and serum IgA levels in individuals with type 1 and 2 diabetes, in relation to a control group of healthy individuals. Methods: This case-control study was conducted on 76 individuals with diabetes (31 with type 1 diabetes and 45 with type 2 diabetes) and 24 healthy individuals. After obtaining the code of ethics and informed consent, serum and salivary IgA levels as well as fasting glucose, were measured for each participant. The data were analyzed using SPSS version 16 statistical software and the Spearman, Kruskal-Wallis, and Mann-Whitney tests. Results: The results showed a significant difference among the three groups (type 1 diabetes, type 2 diabetes, and healthy group) based on Fasting Blood Glucose, Hemoglobin A1c, Immunoglobulin A, salivary sugar, and salivary IgA (p&lt;0.001). Additionally, in the case group, parameters such as FBS, HbA1c, and salivary IgA showed a significant correlation with salivary sugar. Conversely, in the control group, only the salivary sugar level demonstrated a significant relationship with serum glucose level. The study's findings indicated that serum and salivary IgA levels were lower and higher, respectively, in the control subjects compared to the diabetic group (p&lt;0.001). Conclusion: In healthy individuals, salivary sugar can serve as an indicator to determine fasting blood sugar levels. In diabetic patients, salivary sugar can predict of FBS, HbA1c, and salivary IgA levels.

B cell senescence promotes age-related changes in oral microbiota.

In recent years, there has been increasing attention towards understanding the relationship between age-related alterations in the oral microbiota and age-associated diseases, with reports emphasizing the significance of maintaining a balanced oral microbiota for host health. However, the precise mechanisms underlying age-related changes in the oral microbiota remain elusive. We recently reported that cellular senescence of ileal germinal center (GC) B cells, triggered by the persistent presence of commensal bacteria, results in diminished IgA production with aging and subsequent alterations in the gut microbiota. Consequently, we hypothesize that a similar phenomenon may occur in the oral cavity, potentially contributing to age-related changes in the oral microbiota. Examination of p16-luc mice, wherein the expression of the senescent cell marker p16INK4a can be visualized, raised under specific pathogen-free (SPF) or germ-free (GF) conditions, indicated that, unlike ileal GC B cells, the accumulation of senescent cells in GC B cells of cervical lymph nodes increases with age regardless of the presence of commensal bacteria. Furthermore, longitudinal studies utilizing the same individual mice throughout their lifespan revealed concurrent age-related alterations in the composition of the oral microbiota and a decline in salivary IgA secretion. Further investigation involving Rag1-/- mice transplanted with B cells from wild-type or p16INK4a and p21Waf1/Cip1 -double knockout mice unveiled that B cell senescence leads to reduced IgA secretion and alteration of the oral microbiota. These findings advance our understanding of the mechanism of age-associated changes in the oral microbiota and open up possibilities of their control.

Exploring the impact of bubble type on sensory stimulation in drinks

This study explores the impact of various types of carbonation on sensory stimulation in the mouth, salivary secretion and the neurotransmitter substance P (SP), as well as body responses such as heart rate (HR) and Galvanic Skin Response (GSR). Three types of carbonation (one made using a soda machine, another carbonated with a gasifier, and the last commercial sparkling water) were used to produce different bubbles resulting in distinct sensory characteristics assessed by a trained panel. The impact of carbonation was measured by recording changes in salivary flow rate, SP levels, salivary secretory immunoglobulin A (SIgA), HR, and GSR in fifteen healthy participants. The results showed that the bubble type only affected the sensory perception of carbonation. Regardless of bubble type, carbonation increased salivary flow rate and SP values, SigA and HR. These characteristics are being sought to improve treatments for dysphagia or dry mouth. Therefore, these findings highlight the potential therapeutic application of carbonation in these situations.

Low Salivary IgA Levels Against PAc (361-386) as a Risk Factor for Root Caries in Older Adults.

This study aimed to assess the intricate relationship between salivary IgA antibody levels to PAc (361-386) (PPA), mutans streptococci colonization, and root caries development in older adults. This study included 307 participants aged 76 years residing in Niigata city, Japan. Clinical oral examinations were performed at baseline in 2004 and 1 year later, during which the total number of untreated and treated root caries was assessed using the root decayed, filled tooth (DFT) index. The stimulated saliva samples were collected using the spitting method during the baseline survey. Salivary IgA antibody levels to amino acid residues 361-386 of Streptococcus mutans PAc were quantified using an enzyme-linked immunosorbent assay. Statistical analyses, including the χ2 test, Mann-Whitney U test, and logistic regressions, were performed to examine the association of increased root DFT with the independent variables. Among the 307 participants (53.1% men), the mean root DFT at baseline was 3.77 ± 3.66, and 36.5% of the study sample exhibited increased root DFT after 1 year with a mean increment of 0.36 ± 0.48. Participants with increase in root DFT after 1 year had significantly higher rates of low PPA levels (≤ 25th percentile) than those without increased root DFT (p = 0.020). Low PPA levels (≤ 25th percentile) were significantly more likely to have an increased risk of root caries development compared with PPA levels > 25th percentile (adjusted OR: 1.88, 95% CI: 1.09-3.25). Low PPA levels and root caries incidence correlated significantly, suggesting that low levels of salivary IgA antibody to PAc (361-386) may serve as a risk factor for increased root caries in older adults.

Study on the relationship between EEG and salivary IgE under step-change temperature environments

The salivary immunoglobulin E (IgE) level that usually acts as an indicator of human immunity could change significantly with the air temperature. Electroencephalography (EEG) is a commonly used technique to assess the thermal responses of the human body to the environment. However, the relations between them under step-change temperatures would still need more evidence. Experiments were conducted in this study to explore the EEG–IgE relation. Three step-changed temperature conditions in the controlled environment by a climate chamber were selected in this study, under which the air temperature was suddenly transitioned from a low temperature of 15°C to higher temperatures of 18°C, 24°C and 30°C, respectively, before returning to the initial low-temperature condition. The subjective questionnaires, the EEG signals and the salivary samples from 14 subjects in these three step-changed temperature conditions were collected. Results showed that the thermal comfort voting was significantly correlated with the EEG spectral power and the IgE concentration. In addition, a significant negative correlation between the frontal lobe spectral power and the salivary IgE changes was observed. The spectral power of the frontal lobe could be used as an objective indicator to evaluate the salivary IgE levels under step-change temperature environments. This study has provided some guidance for future studies of the human immunity responses to the indoor environment in different seasons.

The impact of vaccine type and booster dose on the magnitude and breadth of SARS-CoV-2-specific systemic and mucosal antibodies among COVID-19 vaccine recipients

The COVID-19 pandemic has had a major impact on global health and economy, which was significantly mitigated by the availability of COVID-19 vaccines. The levels of systemic and mucosal antibodies against SARS-CoV-2 correlated with protection. However, there is limited data on how vaccine type and booster doses affect mucosal antibody response, and how the breadth of mucosal and systemic antibodies compares. In this cross-sectional study, we compared the magnitude and breadth of mucosal and systemic antibodies in 108 individuals who received either the BNT162b2 (Pfizer) or CoronaVac (SinoVac) vaccine. We found that BNT162b2 (vs CoronaVac) or booster doses (vs two doses) were significantly associated with higher serum IgG levels, but were not significantly associated with salivary IgA levels, regardless of prior infection status. Among non-infected individuals, serum IgG, serum IgA and salivary IgG levels were significantly higher against the ancestral strain than the Omicron BA.2 sublineage, but salivary IgA levels did not differ between the strains. Salivary IgA had the weakest correlation with serum IgG (r = 0.34) compared with salivary IgG (r = 0.63) and serum IgA (r = 0.60). Our findings suggest that intramuscular COVID-19 vaccines elicit a distinct mucosal IgA response that differs from the systemic IgG response. As mucosal IgA independently correlates with protection, vaccine trials should include mucosal IgA as an outcome measure.

Heyndrickxia coagulans strain SANK70258 suppresses symptoms of upper respiratory tract infection via immune modulation: a randomized, double-blind, placebo-controlled, parallel-group, comparative study.

Probiotic consumption strongly influences local intestinal immunity and systemic immune status. Heyndrickxia coagulans strain SANK70258 (HC) is a spore-forming lactic acid bacterium that has immunostimulatory properties on peripheral tissues. However, few reports have examined the detailed effectiveness of HC on human immune function and its mechanism of action. Therefore, we conducted a randomized, double-blind, placebo-controlled, parallel-group study to comprehensively evaluate the effects of HC on immunostimulatory capacity, upper respiratory tract infection (URTI) symptoms, and changes in intestinal organic-acid composition. Results of a questionnaire survey of URTI symptoms showed that runny nose, nasal congestion, sneezing, and sore throat scores as well as the cumulative number of days of these symptoms were significantly lower in the HC group than in the placebo group during the study period. Furthermore, the salivary secretory immunoglobulin A (sIgA) concentration was significantly higher, and the natural killer (NK) cell activity tended to be higher in the HC group than in the placebo group. In addition, we performed an exposure culture assay of inactivated influenza virus on peripheral blood mononuclear cells (PBMCs) isolated from the blood of participants in the HC and placebo groups. Gene-expression analysis in PBMCs after culture completion showed that IFNα and TLR7 expression levels were significantly higher in the HC group than in the placebo group. In addition, the expression levels of CD304 tended to be higher in the HC group than in the placebo group. On the other hand, the HC group showed a significantly higher increase in the intestinal butyrate concentration than the placebo group. HC intake also significantly suppressed levels of IL-6 and TNFα produced by PBMCs after exposure to inactivated influenza virus. Collectively, these results suggest that HC activated plasmacytoid dendritic cells expressing TLR7 and CD304 and strongly induced IFNα production, subsequently activating NK cells and increasing sIgA levels, and induced anti-inflammatory effects via increased intestinal butyrate levels. These changes may contribute to the acquisition of host resistance to viral infection and URTI prevention.

Effect of aromatic massage on brain waves and physiological indices of older adults.

Massage and aromatherapy are frequently used by older adults as alternative interventions to enhance immunity and induce relaxation. This pilot study evaluated the effect of massage therapy with oil and aromatherapy alone and in combination using objective biological indices. Twenty-eight participants recruited by convenience sampling included adults aged between 25 and 65 years (Group 1), elderly individuals over 65 years without nursing care (Group 2), and older adults over 65 needing long-term nursing support (Group 3). A multiple-group pretest-post-test design was employed, and the effect among the three groups was compared. Interventions included: (i) oil massage therapy; (ii) aromatherapy; and (iii) aroma oil massage therapy. Each therapy session lasted 5 min, with 3 min of observation before and after the session and 10 min interval between sessions. Group 3 omitted one therapy (2: aromatherapy) to reduce their physical burden. An electroencephalogram (EEG) was recorded for α, β, and θ activities of brain waves. EEG data were collected at three points: before, during, and after each treatment. Salivary secretory immunoglobulin A (s-IgA) concentration, oxygen saturation (SPO2), and pulse rate were measured before and after each session. Across all therapy modalities, there was a noticeable increase in the α wave, indicative of relaxation, during the treatment. Significant differences were observed before and during the oil massage in both Group 1 and Group 2. Aromatherapy demonstrated a significant difference before and during treatment in Group 1. Among the biological parameters, s-IgA levels indicated no significant changes. The pulse rate decreased with oil massage. Significant differences were noted before and after therapy in all cases for SPO2 and in Group 2 for pulse rate. Three therapies induced EEG and physiological changes in the adult group and older adults without nursing care. However, these effects are limited in older adults requiring nursing care.

Lower Humoral and Cellular Immunity Following Asymptomatic SARS-CoV-2 Infection Compared to Symptomatic Infection in Education (The ACE Cohort)

PurposeAsymptomatic SARS-CoV-2 infections were widely reported during the COVID-19 pandemic, acting as a hidden source of infection. Many existing studies investigating asymptomatic immunity failed to recruit true asymptomatic individuals. Thus, we conducted a longitudinal cohort study to evaluate humoral- and cell-mediated responses to infection and vaccination in well-defined asymptomatic young adults (the Asymptomatic COVID-19 in Education [ACE] cohort).MethodsAsymptomatic testing services located at three UK universities identified asymptomatic young adults who were subsequently recruited with age- and sex-matched symptomatic and uninfected controls. Blood and saliva samples were collected after SARS-CoV-2 Wuhan infection, and again after vaccination. 51 participant’s anti-spike antibody titres, neutralizing antibodies, and spike-specific T-cell responses were measured, against both Wuhan and Omicron B.1.1.529.1.ResultsAsymptomatic participants exhibited reduced Wuhan-specific neutralization antibodies pre- and post-vaccination, as well as fewer Omicron-specific neutralization antibodies post-vaccination, compared to symptomatic participants. Lower Wuhan and Omicron-specific IgG titres in asymptomatic individuals were also observed pre- and post-vaccination, compared to symptomatic participants. There were no differences in salivary IgA levels. Conventional flow cytometry analysis and multi-dimensional clustering analysis indicated unvaccinated asymptomatic participants had significantly fewer Wuhan-specific IL-2 secreting CD4+ CD45RA+ T cells and activated CD8+ T cells than symptomatic participants, though these differences dissipated after vaccination.ConclusionsAsymptomatic infection results in decreased antibody and T cell responses to further exposure to SARS-CoV-2 variants, compared to symptomatic infection. Post-vaccination, antibody responses are still inferior, but T cell immunity increases to match symptomatic subjects, emphasising the importance of vaccination to help protect asymptomatic individuals against future variants.

Salivary IgG and IgA in newborn calves and the possible role in the assessment of passive immunity transfer.

The transfer of immunoglobulins from the mother to newborns is widely recognized as a critical event for safeguarding offspring against potentially life-threatening infectious diseases. Mainly for this reason, this study aimed to assess the concentrations of immunoglobulin G (IgG) and immunoglobulin A (IgA) in the saliva of newborn calves and explore its potential use for monitoring passive immunity transfer from cows to calves, as also to evaluate how colostrum intake affects serum and saliva IgG and IgA concentrations. The quality of colostrum samples was evaluated using an optical refractometer before administration to the calves. Saliva and blood samples from 24 calves were obtained at the day of birth (T0) and 2 days after (T2) for determination of serum concentrations of total protein by refractometer, IgG and IgA (both on serum and saliva) by ELISA test. Positive correlations were observed between salivary IgA at T2 and salivary IgG at T2. A significant increase in both IgG and IgA levels in calf serum and saliva was noted. Salivary IgA levels can reflect salivary IgG levels. These findings suggest the potential utility of IgA in monitoring passive immunity transfer, and do not exclude saliva as an alternative, practical, and non-invasive matrix for assessing passive immunity transfer.