Salivary Immunoglobulin G Research Articles

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.

Influence of Saliva Collection Method on the Detection of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and Immunoglobulin G (IgG) Antibodies in the Saliva: A Cross-Sectional Study

ABSTRACT Background: Although the nasopharyngeal swabs (NPS) are considered as the gold standard specimen for the clinical diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus in the coronavirus disease 2019 (COVID-19), they pose several limitations such as the high risk of exposure, discomfort to the patients, and requirement of trained healthcare professionals. Aim: This study aimed to investigate “saliva” as an alternate source and the influence of the method of saliva collection on the sensitivity of SARS-CoV-2 detection. Materials and Methods: In this cross-sectional study, patients were screened for the COVID-19 infection with NPS. Saliva was collected from the same patients by four different methods (expectoration, drooling, gargling, and using salivary swabs) and stored at 80°C. Saliva samples of the patients who were detected positive for SARS-CoV-2 were analyzed for viral load by RT-qPCR and immunoglobulin G (IgG) levels by ELISA. Results: Out of 350 patients screened, 43 patients were included in the study, which were found to be positive for COVID-19 as evidenced by RT-PCR in the NPS (positivity rate-12.2%). Expectorated saliva exhibited 78.5% sensitivity and drooling method showed 22.2% sensitivity, whereas the salivary swab and gargling method yielded 21.42% and 16.66% sensitivity, respectively. Furthermore, the sensitivity of SARS-CoV-2 detection was reduced to 18.1% and 0.0% in the saliva collected by salivary swab and gargling method above the cycle threshold value 25.0 (NPS). Conclusion: Interestingly, salivary IgG showed better concordance with the viral load as compared to the serum IgG (R20.23 vs 0.04, P = 0.044). Expectorated saliva is a better specimen as compared to the drooling, gargling, and salivary swabs for SARS-CoV-2 viral detection for the clinical diagnosis of COVID-19.

Storage stability and HILIC-UHPLC-FLR analysis of immunoglobulin G N-glycome from saliva.

Immunoglobulin G (IgG) is the most abundant antibody in the blood and plays a critical role in host immune defense against infectious agents. Glycosylation is known to modulate the effector functions of IgG and is involved in disease development and progression. It is no surprise that the N-glycome of IgG from plasma has already been proposed as a biomarker for various physiological and pathological conditions. However, because saliva is easy to collect, it could be useful for exploring the functional role of salivary IgG N-glycosylation and its potential as a diagnostic biomarker. Therefore, in this study, we described a method for N-glycome analysis of IgG from saliva samples. Salivary IgG N-glycans were analyzed by ultra-high-performance liquid chromatography based onhydrophilic interactions with fluorescence detection (HILIC-UHPLC-FLR). In addition, we compared IgG N-glycan profiles from saliva with those from plasma, assessed the stability of salivary IgG N-glycan profiles under different storage conditions, and evaluated the effects of using a saliva preservation medium. This study provides an ultrasensitive UHPLC method for the analysis of total IgG N-glycosylation from saliva, gives insight into storage stability of salivary IgG, and highlights its (dis)advantages for further biomarker-related research.

Salivary Antibody Responses to Two COVID-19 Vaccines following Different Vaccination Regimens.

Background: To date, little is known about the salivary mucosal immune response following different COVID-19 vaccine types or after a booster (3rd) dose of the BNT162b2 (BNT) vaccine. Methods: A total of 301 saliva samples were collected from vaccinated individuals and arranged into two cohorts: cohort 1 (n = 145), samples from individuals who had received two doses against SARS-CoV-2; cohort 2 (n = 156), samples from individuals who had received a booster of BNT vaccine. Cohorts 1 and 2 were sub-stratified into three groups based on the types of first and second doses (homologous BNT/BNT, homologous ChAdOx1/ChAdOx1, or heterologous BNT/ChAdOx1vaccinations). Salivary immunoglobulin G (IgG) response to SARS-CoV-2 spike glycoprotein was measured by ELISA, and clinical demographic data were collected from hospital records or questionnaires. Results: Salivary IgG antibody responses against different vaccines, whether homologous or heterogeneous vaccination regimens, showed similar levels in cohorts 1 and 2. Compiling all groups in cohort 1 and 2 showed significant, albeit weak, negative correlations between salivary IgG levels and time (r = -0.2, p = 0.03; r = -0.27, p = 0.003, respectively). In cohort 2, the durability of salivary IgG after a booster dose of BNT162b2 significantly dropped after 3 months compared to the <1 month and 1-3 months groups. Conclusions: Different COVID-19 vaccine types and regimens elicit similar salivary anti-SARS-CoV-2 IgG with modest waning over time. Boosting with BNT162b2 vaccine did not produce an evident increase in mucosal IgG response whereby COVID-19 recovered subjects show higher salivary IgG than naive, post-vaccination subjects. The ChAdOx1/ChAdOx1 regimen showed better correlation between salivary IgG levels and durability. These findings highlight the importance of developing oral or intra-nasal vaccines to induce stronger mucosal immunity.

Salivary IgG to SARS-CoV-2 indicates seroconversion and correlates to serum neutralization in mRNA-vaccinated immunocompromised individuals

BackgroundImmunocompromised individuals are highly susceptible to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Whether vaccine-induced immunity in these individuals involves oral cavity, a primary site of infection, is presently unknown.MethodsImmunocompromised patients (n = 404) and healthy controls (n = 82) participated in a prospective clinical trial (NCT04780659) encompassing two doses of the mRNA BNT162b2 vaccine. Primary immunodeficiency (PID), secondary immunodeficiencies caused by human immunodeficiency virus (HIV) infection, allogeneic hematopoietic stem cell transplantation (HSCT)/chimeric antigen receptor T cell therapy (CAR-T), solid organ transplantation (SOT), and chronic lymphocytic leukemia (CLL) patients were included. Salivary and serum immunoglobulin G (IgG) reactivities to SARS-CoV-2 spike were measured by multiplex bead-based assays and Elecsys anti-SARS-CoV-2 S assay.FindingsIgG responses to SARS-CoV-2 spike antigens in saliva in HIV and HSCT/CAR-T groups were comparable to those of healthy controls after vaccination. The PID, SOT, and CLL patients had weaker responses, influenced mainly by disease parameters or immunosuppressants. Salivary responses correlated remarkably well with specific IgG titers and the neutralizing capacity in serum. Receiver operating characteristic curve analysis for the predictive power of salivary IgG yielded area under the curve (AUC) = 0.95 and positive predictive value (PPV) = 90.7% for the entire cohort after vaccination.ConclusionsSaliva conveys vaccine responses induced by mRNA BNT162b2. The predictive power of salivary spike IgG makes it highly suitable for screening vulnerable groups for revaccination.FundingKnut and Alice Wallenberg Foundation, Erling Perssons family foundation, Region Stockholm, Swedish Research Council, Karolinska Institutet, Swedish Blood Cancer Foundation, PID patient organization of Sweden, Nordstjernan AB, Center for Medical Innovation (CIMED), Swedish Medical Research Council, and Stockholm County Council (ALF).

Changes in immunoglobulin A and immunoglobulin G concentrations in the saliva of Japanese Black beef cows during calving: A pilot study.

Immunoglobulin A (IgA) in saliva, mostly consisting of secretory IgA, plays an important role in the mucosal immune mechanism. This study evaluated changes in salivary IgA and Immunoglobulin G (IgG) concentrations in Japanese Black cows (n = 16) during calving. Individual saliva samples were collected -2, 0, and 2weeks postpartum. Immunoglobulin concentrations differed significantly among weeks (P < 0.05), but the effect of parity and week × parity was insignificant. Salivary IgA concentrations decreased drastically (P < 0.05) after calving compared with those at -2weeks postpartum and remained low until 2weeks postpartum. The salivary IgG concentrations decreased gradually during peripartum and differed at -2 and 2weeks postpartum (P < 0.05). Considering the immunoglobulin concentrations at -2weeks postpartum as the reference standard for 100%, the rates of decrease in IgA concentrations (36.7 ± 6.9%) were significantly lower (P < 0.05) than those of IgG (70.3 ± 10.1%) at calving day. To our knowledge, this is the first report indicating that salivary IgA concentrations decreased drastically after calving in Japanese Black cows. Further studies monitoring the secretory functions of IgA in the salivary gland are essential for understanding maternal immunity in cattle.

Appearance of IgG to SARS-CoV-2 in Saliva Effectively Indicates Seroconversion in mRNA Vaccinated Immunocompromised Individuals

Background: mmunocompromised individuals are highly susceptible to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. Whether vaccine-induced immunity in these individuals involves the oral cavity, a primary site of infection, is presently unknown.Methods: Immunocompromised individuals (n=404) and healthy controls (n=82) participated in a prospective clinical trial encompassing two doses of the mRNA BNT162b2 vaccine. Immunocompromised individuals included primary immunodeficiencies (PID) and secondary immunodeficiencies caused by human immunodeficiency virus (HIV) infection, allogeneic hematopoietic stem cell transplantation (HSCT)/chimeric antigen receptor T cell therapy (CAR-T), solid organ transplantation (SOT), and chronic lymphocytic leukemia (CLL). Saliva and serum samples were collected at four time points from the first vaccine dose until 2 weeks after second dose. SARS-CoV-2 spike specific immunoglobulin G (IgG) responses were quantified by a multiplex bead-based assay in saliva and correlated to paired serum IgG titers determined by Elecsys Anti-SARS-CoV-2 S assay.Results: IgG responses to the SARS-CoV-2 spike full-length tr­imeric glycoprotein (Spike-f) and S1 subunit in saliva in the HIV and HSCT/CAR-T groups were comparable to healthy controls. In contrast, PID, SOT, and CLL patients all displayed weaker responses which were mainly influenced by disease parameters or immunosuppressants. Salivary IgG levels strongly correlated with serum IgG titers on days 21 and 35 (rho=0.8079 and 0.7768, p=Conclusions: Saliva conveys humoral responses induced by BNT162b2 vaccination. The predictive power makes it highly suitable for screening low responding/vulnerable groups for revaccination.Funding: Knut and Alice Wallenberg Foundation, Erling Perssons family foundation, Region Stockholm, Swedish Research Council, Karolinska Institutet, The Swedish Blood Cancer Foundation and the organization for PID patient group in Sweden, and Nordstjernan AB. Center for Medical Innovation (CIMED), the Swedish Medical Research Council and the Stockholm County Council (ALF).Declaration of Interests: The authors have declared that no conflict of interest exists.Ethics Approval Statement: The study was approved by the Swedish Medical Product Agency (ID 5.1-2021-5881) and the Swedish Ethical Review Authority (ID 2021-00451 and 2020-06381). All participants provided written informed consent. Trial Registration: This trial was registered at EudraCT (no. 2021-000175-37), and clinicaltrials.gov (no. 2021-000175-37).

Salivary total Immunoglobulin G as a surrogate marker of oral immune activity in salivary bioscience research

The integration of salivary biomeasures in biobehavioral, psychophysiological, and clinical research has greatly expanded our ability to study the biopsychosocial processes underlying health. Much of this research, however, has failed to adequately assess and adjust for the impact of oral immune activity on salivary biomeasure concentrations and associations with serum levels. Aiming to improve the validity and reliability of salivary biomeasure data, we examine salivary total Immunoglobulin G (IgG) as a potential surrogate marker of oral inflammation and immune activity. During a single study visit in Baltimore, Maryland, healthy young adult participants provided matched blood and saliva samples (N=99; age 18–37 years, 42% female) and completed an oral health questionnaire. Biospecimens were assayed for total IgG and immune markers related to inflammation (cytokines), blood in saliva (transferrin), and tissue remodeling (matrix metalloproteinase-8). Total IgG (μg/mL) concentrations were higher in serum than saliva. Salivary total IgG was associated with some self-reported oral health measures, and strongly positively associated with all salivary immune markers. Controlling for salivary total IgG may be a feasible, affordable approach to adjusting salivary biomeasure findings for the influence of the oral immune environment when it is not possible or practical to obtain clinical oral health data.

Salivary IgG levels in neonatal calves and its association to serum IgG: an observational pilot study.

The diagnosis of inadequate transfer of colostrum immunoglobulin G (IgG) to calf serum, often known as failure of passive transfer (<10 g/L IgG1 at 24 to 48 h), necessitates blood sampling from the calf and in some instances the presence of a veterinarian. Sampling saliva is both less invasive and easy for the producer. Previous research has shown that quantification of saliva IgG is possible in juvenile and adult cattle. The objectives of this observational pilot study were to investigate whether IgG can be quantified in neonatal calf saliva, if it is correlated to serum IgG concentrations, and if the indirect quantification of saliva IgG is achievable by use of a digital refractometer. Paired blood and saliva samples were collected from 20 healthy dairy calves aged 1 to 3 d. In these samples, IgG was quantified directly with single radial immunodiffusion and indirectly by use of a digital refractometer indicating Brix % (a subsample of n = 12 saliva samples). A strong positive correlation (r = 0.7, P < 0.001) between saliva IgG (mean ± SD; 0.2 ± 0.11 g/L) and serum IgG (32.1 ± 11.94 g/L) was found. Saliva IgG ranged from the lowest detectable value, 0.1 g/L (n = 6 samples) to 0.6 g/L. Saliva Brix (1.2 ± 0.69%) was not significantly correlated to serum IgG (n = 12, r = 0.43, P = 0.155); however, it was significantly correlated to saliva IgG (n = 12, r = 0.7, P = 0.018) and Brix in serum (n = 12, r = 0.7, P = 0.013). We conclude that IgG was quantifiable in most of the saliva samples. For saliva IgG to be of any value with regards to detecting failure of passive transfer, future studies should investigate methods that can detect IgG <0.1 g/L. The results indicate that saliva IgG can be used to predict serum IgG at levels above 10 g/L, which may warrant further exploration of the use of saliva in the surveillance of failure of passive transfer. The results of the current pilot study did not support the potential usage of a Brix % refractometer to quantify saliva IgG.

Minimally Invasive Saliva Testing to Monitor Norovirus Infection in Community Settings

BackgroundNorovirus is a leading cause of acute gastroenteritis worldwide. Routine norovirus diagnosis requires stool collection. The goal of this study was to develop and validate a noninvasive method to diagnose norovirus to complement stool diagnostics and to facilitate studies on transmission.MethodsA multiplex immunoassay to measure salivary immunoglobulin G (IgG) responses to 5 common norovirus genotypes (GI.1, GII.2, GII.4, GII.6, and GII.17) was developed. The assay was validated using acute and convalescent saliva samples collected from Peruvian children <5 years of age with polymerase chain reaction (PCR)–diagnosed norovirus infections (n = 175) and controls (n = 32). The assay sensitivity and specificity were calculated to determine infection status based on fold rise of salivary norovirus genotype-specific IgG using norovirus genotype from stool as reference.ResultsThe salivary assay detected recent norovirus infections and correctly assigned the infecting genotype. Sensitivity was 71% and specificity was 96% across the evaluated genotypes compared to PCR-diagnosed norovirus infection.ConclusionsThis saliva-based assay will be a useful tool to monitor norovirus transmission in high-risk settings such as daycare centers or hospitals. Cross-reactivity is limited between the tested genotypes, which represent the most commonly circulating genotypes.

Influence of occupational stress on salivary immunoglobulin G concentration in employees

To investigate the possibility of salivary immunoglobulin G(IgG) as an objective assessment index for occupational stress. In September 2014, a total of 186 employees in a solar photovoltaic company were selected as research subjects, and a questionnaire survey was performed. Enzyme-linked immunosorbent assay was used to measure salivary IgG concentration. The salivary IgG concentration showed a significant difference between employees with different working years and shifts(P<0.05). The employees with ≤15 working years had a lower salivary IgG concentration than those with >20 working years (49.93±7.97 μg/ml vs 53.80±8.22 μg/ml), and the employees with long-day shifts had a higher salivary IgG concentration than those with day-night shifts(54.98±7.62 μg/ml vs 51.85±7.94 μg/ml). The employees with low levels of job demands and job danger had a significantly higher salivary IgG concentration than those with high levels(54.09±6.68 μg/ml vs 50.65±8.81 μg/ml, P<0.05; 53.73±7.35 μg/ml vs 50.73±8.73 μg/ml, P<0.05). The employees with a high score of mental health had a significantly higher salivary IgG concentration than those with a low score(54.39±5.28 μg/ml vs 50.73±9.36 μg/ml, P<0.05). The salivary IgG concentration was positively correlated with the score of mental health(r=0.314, P<0.05), but negatively correlated with job demands, job routinization, job danger, job prospects, physical complaints, and daily stress(r=-0.249, -0.159, -0.157, -0.030, -0.035, and -0.176, all P<0.05). The multivariate linear regression analysis showed that the salivary IgG concentration was mainly influenced by job demands and mental health. Salivary IgG concentration can be applied as an objective assessment index for occupational stress.

Correlation between job burnout and salivary immunoglobulin G in employees

To investigate the influence of job burnout on salivary immunoglobulin G(IgG) concentration in employees. In September 2014, evaluation of job burnout was performed for 186 employees in a solar photovoltaic company, and enzyme-linked immunosorbent assay was used to measure salivary IgG concentration. The employees with over 20 working years had a significantly higher salivary IgG concentration than those with ≤15 working years(53.80±8.22 μg/ml vs 49.93±7.97 μg/ml, P<0.05). The employees with long-day shifts had a significantly higher salivary IgG concentration than those with day-night shifts (54.98±7.62 μg/ml vs 51.85±7.94 μg/ml, P<0.05). The employees with depersonalization had a significantly lower salivary IgG concentration than those without depersonalization(50.69±9.89 vs 53.19±6.54, P<0.05). The salivary IgG concentration was negatively correlated with the scores of emotional exhaustion, depersonalization, and job burnout (r=-0.194, -0.152, and -0.210, all P<0.05). Job burnout is negatively correlated with salivary IgG concentration, which tends to decrease with the increasing severity of job burnout. Therefore, salivary IgG can be used as a biomarker for the identification and evaluation of job burnout.

Self-perceived oral health and whole salivary immunoglobulin G levels in habitual gutka-chewers and nonchewers.

To assess self-perceived oral health and whole salivary immunoglobulin G (IgG) levels among habitual gutka-chewers and nonchewers (controls). Fifty gutka-chewers and fifty controls were included. Demographic data and self-perceived oral health status (pain in teeth, pain on chewing, bleeding gums (BG), bad breath, loose teeth and daily oral hygiene protocols) were collected using a questionnaire. Unstimulated whole saliva (UWS) was collected and unstimulated whole salivary flow rate (UWSFR) was determined. Whole salivary IgG levels were determined using standard techniques. Odds ratios were calculated for oral symptoms and group differences in protein levels were compared using one-way analysis of variance (α± <5%). BG was more often reported by gutka-chewers than controls (P < 0.05). There was no significant difference in UWSFR and self-perceived pain in teeth, pain on chewing, bad breath and loose teeth among gutka-chewers and controls. IgG levels were significantly higher among gutka-chewers than controls (P < 0.01). Among gutka-chewers, whole salivary IgG levels were comparable individuals with and without self-perceived oral symptoms. Among controls, IgG levels in UWS were significantly higher among individuals who had BG than those who did not (P < 0.05). Self-perceived oral health is worse and whole salivary IgG levels are higher in gutka-chewers compared to controls.

Impact of scaling and root planing with adjunct essential-oil-based mouthwash usage on whole salivary IgG levels in patients with periodontal inflammation.

The aim was to assess the effect of scaling and root planing (SRP) with and without adjunct use of an essential-oil-based-mouthwash (EOBM) on whole salivary immunoglobulin G (IgG) levels in patients with periodontal inflammation. Fifty patients with periodontal inflammation were included. Treatment wise, these patients were randomly divided into two groups. In group1, patients underwent SRP and were instructed to rinse with 10 mL of an EOBM twice daily for 30 days, whereas those in group2 underwent SRP and were instructed to rinse with 10 mL of water twice daily for 30 days. Whole saliva samples were collected at baseline and after 40 days of treatment. P-values < 0.05 were considered statistically significant. At baseline, whole salivary IgG levels were comparable among patients in groups 1 (60.5 ±5.5 mg/dL) and 2 (57.3 ±2.4 mg/dL). After 40 days of follow-up, there is a significant decrease in whole salivary IgG levels among patients in group1 (7.2 ±2.4 mg/dL) as compared to those in group2 (26.6 ±4.6 mg/dL) (P < 0.001). SRP, when performed with adjunct use of an EOBM, is more effective in reducing whole salivary IgG levels as compared to when SRP is performed without adjunct use of an EOBM.

Estimation of serum and salivary immunoglobulin G and immunoglobulin A in oral pre-cancer: A study in oral submucous fibrosis and oral lichen planus

Aim:Oral submucous fibrosis (OSMF) and oral lichen planus (OLP) are two frequently reported, potentially malignant disorders with multifactorial etiologies and ambiguous pathogenesis. An immunological pathogenesis has been hypothesized as a causative factor for both. The present study aims to evaluate the role of serum and salivary immunoglobulin G (IgG) and immunoglobulin A (IgA) in both these conditions, by their quantitative estimation.Materials and Methods:Saliva and serum samples were collected from 30 patients, clinically diagnosed and histopathologically confirmed with OSMF, 30 with OLP and 30 age and sex matched controls. The levels of IgG and IgA were estimated by nephelometry.Results:The mean values of serum IgG were marginally higher in both OSMF and OLP groups compared to the controls but this difference was not significant and the mean values of serum immunoglobulin A were marginally decreased in both the study groups compared to the controls but this difference was also not significant. Inconclusively low levels of salivary IgG and IgA were obtained in the three groups.Conclusion:The present study suggests an insignificant association of these immunoglobulins in the pathogenesis of both these diseases.

Scent Recognition of Infected Status in Humans

There is a body of experimental evidence that mice and rats use chemical signals to avoid sexual contact with infected conspecifics. In contrast to animals, body scent of sick humans is employed only in medical diagnostics. A modification of human body odor, due to an infection, has not been studied as a potential signal for choice of a sexual partner. It might, however, be especially important for sexually transmitted infections (STI) because many such infections have no obvious external manifestations. In this study, we have investigated odor pleasantness of young men infected with gonorrhea, Neisseria gonorrhoeae. We collected armpit sweat and saliva from young men (17-25 years old) belonging to three groups: healthy persons (N = 16), young men infected with gonorrhea, Neisseria gonorrhoeae (N = 13), and persons recovered due to specific therapy (N = 5). The sweat samples odor was then assessed by healthy young women (17-20 years old). Concentrations of cortisol, testosterone, immunoglobulin A (IgA), and immunoglobulin G (IgG) were measured in saliva by means of enzyme-linked immunosorbent assay. Subjective rates of odor pleasantness, association of scent of armpit sweat with odor descriptors, stepwise regression of odor pleasantness and salivary cortisol, testosterone, IgA, and IgG. The odor from infected individuals was reported as less pleasant in comparison with the odor of healthy and recovered young men. The scent of infected men was more frequently associated by raters with the descriptor "putrid." Odor pleasantness of the male sweat correlated negatively with concentration of the nonspecific salivary IgA and IgG, which was measured as an indicator of current immunoenhancement. Perhaps, the immune-dependent reduction of the scent pleasantness in the acute phase of STI is part of an evolutionary mechanism ensuring, unconsciously, avoidance of a risky romantic partner.

Correlation of salivary and serum IgG, IgA levels with total protein in oral submucous fibrosis

Oral submucous fibrosis (OSMF) is a disabling, potentially malignant condition of the oral cavity. The aetiology of OSMF is multifactorial but remains obscure. Although arecanut is considered to be the most important causative agent, responses observed in individuals using arecanut vary in relation to quantity and duration. It is considered that an immunological process is responsible for the pathogenesis of disease. We correlated salivary immunoglobulin A (IgA), salivary immunoglobulin G (IgG) and serum immunoglobulin A (IgA), serum immunoglobulin G (IgG), levels by turbidometric immunoassay. We estimated the levels of total serum protein (TSP) and haemoglobin (Hb) to determine the role of nutritional deficiency. The study population comprised 30 cases of OSMF and 10 controls. Five milliliters of blood and 2 ml of saliva were collected. Quantitative analysis of serum and salivary IgG, IgA was done by turbidometric immunoassay. TSP and Hb were estimated by Biuret and cyanmethaemoglobin methods, respectively. All patients showed significant (P < 0.01) increase in serum and salivary IgG, IgA levels as compared to controls. TSP patients showed significant (P < 0.01) decrease as compared to controls. Results of Hb in patients were not significant. The estimation of immunoglobulin levels is important to support the concept of autoimmune basis. Estimation of TSP and Hb suggests that nutrition has a definite role in OSMF.

Tracking of plasma antibodies against Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis during 15 years

Background: Plasma antibody measurements of antibody levels to periodontal pathogens may be used to support diagnosis, disease activity, classification, and prognosis of periodontitis.Objective: The aim of this study was to investigate the long-term stability of plasma antibody levels against Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis.Design: Plasma immunoglobulin G (IgG) antibody levels against the pathogens were analyzed annually during 15 years from 21 voluntary subjects, whose periodontal status was not known at the point of selection. The total number of plasma samples was 315. In connection of the last sampling, the clinical and radiographic periodontal status was examined. Pooled bacterial samples from periodontal pockets, as well as salivary samples were collected for A. actinomycetemcomitans and P. gingivalis detection, and antibody determinations, respectively. According to the clinical status, six subjects had periodontitis, whereas 15 did not.Results: Plasma IgG-class antibody levels to periodontal pathogens remained extremely stable during the 15-year period and no significant (p>0.05) intra-individual variations were observed. Retrospectively, the average plasma IgG antibody levels against A. actinomycetemcomitans and P. gingivalis were 1.6–2.3 (p<0.05) and 1.4–1.7 (p<0.05) fold higher in the subjects with periodontitis than those without, respectively, during the whole 15-year tracking. As expected, at the time of the periodontal examination the plasma and salivary IgG antibody levels were associated both with periodontitis and bacterium-positivity.Conclusions: Plasma IgG levels against A. actinomycetemcomitans and P. gingivalis are extremely stable during 15 years both in subjects with and without periodontitis.

Transcutaneous immunization with an outer membrane protein of Porphyromonas gingivalis without adjuvant elicits marked antibody responses

We have previously reported that specific immunoglobulin G (IgG) antibodies induced by transcutaneous immunization (TCI) with a 40-kDa outer membrane protein (40k-OMP) of Porphyromonas gingivalis, with cholera toxin (CT) as adjuvant, inhibited coaggregation by P. gingivalis. In this study, we further pursue the potential of the 40k-OMP as a transcutaneous vaccine. TCI of rats administered 40k-OMP elicited significant 40k-OMP-specific serum IgG and IgA, as well as salivary IgG antibody titers. Importantly, these antibody responses were induced without adjuvant. Thus, both serum and saliva antibody titers induced by TCI with the 40k-OMP alone were identical to those of 40k-OMP plus cholera toxin as adjuvant. The serum antibody responses induced by 40k-OMP persisted for more than 140 days. On the other hand, salivary IgG anti-40k-OMP antibodies were gradually decreased. Analysis of antibody-forming cells (AFCs) confirmed the antibody titers by detecting high numbers of 40k-OMP-specific IgG AFCs in spleen and cervical lymph node. Since 40k-OMP-specific IgG inhibited the coaggregation of P. gingivalis with Streptococcus gordonii, and the hemagglutinin activity of P. gingivalis, TCI with the 40k-OMP may be important as an adjuvant-free immunogen for the prevention of chronic periodontitis.

Detection of anti-protective antigen salivary IgG antibodies in recipients of the US licensed anthrax vaccine

The immune response of anthrax vaccine recipients is not routinely monitored. For field use, a noninvasive test would be beneficial to evaluate the antibody response of anthrax-vaccinated individuals working within a high-risk area of possible exposure. The aim of this cross-sectional study was to determine whether whole saliva can be used as a surrogate matrix for the detection of 83 kDa protective antigen (PA)-specific immunoglobulin G (IgG). An enzyme-linked immunosorbent assay was used for the detection of PA-specific IgG in matched samples (serum and saliva) that were collected from vaccinated and unvaccinated participants. Specimens from 180 individuals revealed a positive correlation (r=0.73; P<0.0001) between the level of PA-specific antibody detected in the saliva and serum. The number of vaccinations influenced both the saliva and serum antibody response. On average, the concentration of serological PA-specific antibodies in the vaccinated group was nearly 1600-fold greater than that in saliva. The magnitude of the salivary anti-PA antibody response was not significantly affected by the consumption of food, beverage, or tobacco products or other factors, which could potentially affect oral fluid properties. These results suggest that an oral fluid-based immunoassay may be a feasible alternative to monitoring the serological antibody response of individuals that have been vaccinated against anthrax.