Humoral immunity in root caries in an elderly population. I.

IgA, IgG and IgM antibody activity (ELISA Units/ml) to Streptococcus mutans, Actinomyces viscous and Escherichia coli CF8 in serum, parotid saliva and whole saliva was measured using the amplified ELISA (a-ELISA) while the concentration (microgram/ml) of each isotype of immunoglobulin as well as albumin and lactoferrin, was determined using sandwich ELISAs. Selection of suitable reagents from those commercially available was based on specificity tests using purified human immunoglobulin; most polyclonal reagents required further absorption to attain class specificity. Cross-absorption studies indicated the absence of patient antibodies that were cross-reactive among the bacteria studied, except for IgM in some cases. Expression of response in ELISA Units (E.U.) per microgram of immunoglobulin, i.e. specific activity, revealed that IgG specific activity was significantly higher in parotid saliva than in either whole saliva or serum for all bacteria studied; serum and whole saliva did not differ except for the higher specific activity in whole saliva to E. coli. The value of one E.U. was determined using the Comparative Antibody-immunoglobulin Capture Assay (CACA). Using this novel method, we estimated that about 0.05 percent of serum IgA was specific for Streptococcus mutans, 0.008 for Actinomyces viscosus and 0.004 for Escherichia coli CF8. The percentage of specific IgM antibodies was higher than for IgA and IgG. The concentration of IgA anti-Streptococcus mutans, Actinomyces viscosus and Escherichia coli levels are approximately 92 ng/ml, 25 ng/ml and 16 ng/ml in whole saliva and 46 ng/ml, 9.4 ng/ml and 6.3 ng/ml in parotid saliva.(ABSTRACT TRUNCATED AT 250 WORDS)     

Salivary IgA responses to Porphyromonas gingivalis in the cynomolgus monkey. I. Total IgA and IgA antibody levels to P. gingivalis

Porphyromonas gingivalis has been associated with the subgingival plaque of advancing disease lesions in various types of periodontitis. Additionally, this species of oral microorganism has been found to increase dramatically in ligature-induced periodontitis in nonhuman primates (Macaca fascicularis) and has recently been shown to induce progressing disease when implanted into the subgingival plaque in this animal model. Although systemic antibody responses have been demonstrated to P. gingivalis in both human and nonhuman primate with periodontitis, no information is available on the oral secretory IgA antibody response to this bacteria. This report describes the methods for reproducible collection of salivary secretions from cynomolgus monkeys and the development of methods for analyzing salivary IgA levels and specific IgA antibody in the saliva reactive with P. gingivalis. Purification of monkey salivary IgA allowed quantification of IgA using an enzyme-linked immunosorbent assay (ELISA). Estimation of total IgA levels in saliva showed approximately a 20% greater level of IgA in whole versus parotid saliva from a group of 13 monkeys, with a 2-3 fold variation in levels among this group of animals. Naturally occurring salivary IgA antibody to P. gingivalis, as measured by ELISA, were routinely detectable but low in whole saliva; however, many of the parotid saliva specimens collected exhibited negligible levels of antibody to this microorganism. The IgA antibody in whole saliva showed nearly an 18-fold variation among the samples from the monkeys. Correlational analyses indicated that, although there was a positive relationship between antibody levels in whole and parotid saliva, the majority of natural IgA antibody in whole saliva appears to be derived from other sources.(ABSTRACT TRUNCATED AT 250 WORDS)     

Indicators of salivary gland inflammation in primary Sjögren's syndrome

The aim of this study was to establish additional indicators in saliva and plasma which are associated with salivary gland inflammation in patients with primary Sjögren's syndrome (SS). ELISA assays were used to determine the concentrations of sICAM-1, sVCAM-1, sIL-2Rz, IgA, IgG, calprotectin and albumin in parotid saliva, whole saliva and plasma samples. Soluble ICAM-1 was present in whole and parotid saliva samples from primary SS patients. Soluble VCAM-1 and sIL-IRx could not be detected in salivary samples from either primary SS or control subjects. IgA, IgG, calprotectin and albumin concentrations were higher in both whole and parotid saliva in the patient group compared with the control group. The results showed increased levels of calprotectin in all saliva samples compared to plasma, suggesting that calprotectin may be locally produced. Increased plasma values of sICAM-1. sVCAM-1, SIL-2Rα, IgA, IgG and calprotectin were detected in primary SS patients when compared to controls. The output/min of IgA. IgG, calprotectin and albumin was decreased in SS patients. Plasma levels of various proteins could offer information concerning glandular and extraglandular inflammatory processes. However, salivary levels of these proteins (particularly sICAM-1) tend to reflect more the local inflammatory activity, providing a convenient and non-invasive tool for diagnosis.     

Cytomegalovirus presence and salivary composition in acquired immunodeficiency syndrome

Parotid and whole saliva was collected from nine patients with acquired immunodeficiency syndrome (AIDS) and nine controls. Cytomegalovirus (CMV) was cultured from both salivary samples in six of the AIDS patients but was not present in any of the controls. In the AIDS samples parotid sodium (p less than 0.05), IgG (p less than 0.01), and albumin (p less than 0.05) were higher than in control samples. Parotid potassium (p less than 0.05) and total protein (p less than 0.05) were lower than control values, whereas flow rate, lactoferrin, lysozyme, IgA, and IgM levels were similar in both sets of samples. AIDS does not appear to affect secretory IgA levels. Sodium (p less than 0.01) and IgA (p less than 0.05) were higher in the whole saliva of AIDS patients. Serum IgG, IgM (p less than 0.01), and IgA (p less than 0.05) were also elevated when compared with the controls. The prevalence of CMV in parotid and whole saliva of AIDS patients is consistent with the known susceptibility of this group to adventitious infection and the predilection of this virus for the salivary glands. The changes in salivary composition suggest a low level of inflammation, which occurs independently of the virus.     

Age-related changes in salivary antibodies to commensal oral and gut biota

The prevalence of mucosally derived infections appears to increase with age, suggesting dysfunction at the mucosal surfaces. The present investigation was undertaken to examine any age-related changes in secretion rates and concentrations of secretory antibodies in whole and parotid saliva in a healthy adult population. A total of 116 subjects were subdivided into the following age groups: 20–39 years, 40–59 years, 60–79 years and 80 years and over. Specific immunoglobulin A (IgA), IgG and IgM antibodies in whole and parotid saliva to Streptococcus mutans (serotype c), Actinomyces viscosus NCTC 10951, and Escherichia coli NCTC 10418 were quantified by enzyme-linked immunosorbent assay. IgA antibodies to all three organisms examined increased with age in both whole and parotid saliva, whereas IgG antibody levels to S. mutans in whole saliva were significantly decreased with age. IgG antibodies to E. coli in parotid saliva were reduced in older age groups. IgM antibody levels to S. mutans were reduced with age in both secretions, whereas IgM antibodies to A. viscosus were greatest in the oldest age groups. No significant changes with age were observed in salivary IgM antibody levels to E. coli. No significant reduction in the secretion rates of IgA antibodies were observed in parotid or whole saliva, whereas IgG and IgM antibody secretion rates to all three microorganisms were reduced in most age groups in both whole and parotid saliva. The results of this investigation have demonstrated age-related changes with salivary antibodies, but, whereas salivary IgG and IgM antibodies showed decreases, salivary IgA levels generally increased with age. This suggests that the ability to form IgA antibody responses is not impaired with increased age, and that secretion rates and functional properties of antibodies may be as important as concentrations in protection against mucosal infective diseases.     

Salivary defense mechanisms in juvenile periodontitis.

The local, saliva-associated defense mechanisms of 28 juvenile periodontitis (JP) patients and their age- and sex-matched controls were studied. Lysozyme, lactoferrin, salivary peroxidase, myeloperoxidase, and thiocyanate concentrations were determined from both whole saliva and parotid saliva. The total concentrations of salivary IgA, IgG, and IgM were assayed. The periodontal condition and the salivary flow rates were registered. Among the JP patients, a significantly elevated concentration of IgG was found in parotid saliva but not in whole saliva. Salivary peroxidase activities were significantly low both in the whole and in the parotid saliva samples of the JP patients, and leukocyte-derived myeloperoxidase was present in significantly low amounts in whole saliva of these patients. Because both glandular (salivary peroxidase) and polymorphonuclear-cell-derived (myeloperoxidase) enzyme activities were low among the JP patients, suppressed peroxidase-mediated host defense mechanisms could be characteristic of JP.     

Antimicrobial proteins in human unstimulated whole saliva in relation to each other, and to measures of health status, dental plaque accumulation and composition.

Saliva antimicrobial proteins may interact in a common system to influence the oral ecology. Clinical studies of antimicrobial protein action thus may require a multiple-protein approach. Multivariate statistical methods have been used to describe possible patterns of interaction for lysozyme, lactoferrin, salivary peroxidase and secretory IgA in stimulated parotid saliva. However, oral microbes are most likely to encounter antimicrobial proteins in mixed resting saliva. Relationships among levels of lysozyme, lactoferrin, salivary peroxidase, and secretory IgA therefore were investigated in whole saliva from 216 subjects, and an attempt made to relate interperson variation in those proteins to differences in health and status, and dental plaque accumulation and composition. All proteins were significantly (alpha = 0.05) correlated with each other (r = 0.38-0.52, p less than 0.001). There was only one axis of common variation among proteins, and that axis was significantly correlated (p less than 0.001) with total protein (r = 0.84) and flow rate (r = -0.56). That pattern deviated from the previous finding that proteins of acinar origin tended to vary independently from proteins of ductal origin in stimulated parotid saliva. The difference between parotid and whole saliva may reflect constitutive secretion of all proteins at low levels of stimulation. Common variation of unstimulated saliva proteins suggests that antimicrobial actions can be compared in subjects at population extremes. There were no significant associations between antimicrobial proteins in whole saliva and measures of health status or plaque accumulation. However, the proportions of Streptococcus sanguis were significantly correlated with lysozyme (r = -0.26), lactoferrin (r = -0.34), peroxidase (r = -0.30), total protein (r = -0.37), flow rate (r = 0.24) and principal-components scores (r = -0.33) in a subset of subjects (n = 85) where commercial biochemical tests were used to supplement species identification by colony morphology. Those findings may indicate that saliva antimicrobial proteins can affect the composition of dental plaque.     

Electrophoretic and immunoelectrophoretic studies of proteins in the aqueous phase of human dental plaque

The presence and amount of some anionic proteins in human plaque fluid were investigated by polyacrylamide gel electrophoresis and quantitative immunoelectrophoresis. Both methods showed albumin to be the major protein component. Of the 8–17 protein bands detected by gel electrophoresis, albumin, amylase, IgG, lactoferrin and IgA were consistently present. Quantitative immunoelectrophoretic studies detected IgA at a concentration similar to that in unstimulated submandibular saliva; IgG, albumin and lactoferrin were present in higher concentrations. IgA was detected at higher concentration by antiserum with specificity for secretory component than by antiserum with specificity for heavy chain only. The mean ratios of some plaque fluid constituents were: IgA:albumin (1:25); IgG:IgA (3.8:1); IgG:albumin (1:7); lactoferrin:IgA (3.6:1); lactoferrin:albumin (1:7). The concentrations of the plaque fluid proteins studied suggest that crevicular fluid greatly influences the protein composition of plaque fluid. The biological activity of IgA or IgG cannot be inferred because of the proteolytic activity in plaque fluid.     

Minor gland saliva flow rate and proteins in subjects with hyposalivation due to Sjogren's syndrome and radiation therapy

In this study, the secretion rate and IgA, albumin and lactoferrin concentrations in minor labial and buccal gland saliva were investigated in individuals with hyposalivation due to primary Sjogren's syndrome (pSS; 10 subjects) or head and neck radiation therapy (RT; 10 subjects) and in their matched controls. Whole saliva was similarly examined. The minor gland saliva flow was measured using the Periotron method. IgA, albumin and lactoferrin concentrations were analysed by ELISA techniques. A general finding was that the flow rate and protein concentrations were lower in labial than in buccal gland saliva. In both hyposalivation groups, the labial minor gland saliva secretion rate was lowered compared to their respective controls. The buccal gland saliva flow rate was significantly reduced in the RT group only. IgA and albumin concentrations were not different from the controls in the labial secretions. The concentration of lactoferrin was increased in the RT group. In buccal saliva, the concentrations of all proteins examined but pSS IgA, were increased compared to the controls. Reduced flow rate and increased protein concentrations were seen for whole saliva where the lactoferrin concentration was higher in RT than in pSS subjects. Thus, our findings suggested that minor gland saliva flow rate and protein concentrations are affected in RT and pSS subjects and to highest extent in the former.     

Protein composition of whole and parotid saliva in healthy and periodontitis subjects

Cystatins are physiological inhibitors of cysteine proteinases and they are widely distributed in human tissues and body fluids including saliva. We previously reported an increased cystatin activity in whole saliva of gingivitis and periodontitis subjects. Based on this result we decided to investigate the type and origin of cystatins involved in this increased cystatin activity by collecting both whole and parotid saliva of 25 healthy and 30 periodontitis subjects. Saliva samples were quantified for cystatins S and C by enzyme-linked immunosorbent assay and cystatin activities were measured toward papain. Besides, three other salivary proteins were determined: the plasma protein albumin, the typical parotid derived amylase and the salivary immunoglobulin IgA. The present investigation shows that levels of total protein and cystatin activity as well as the levels of glandular derived proteins amylase and cystatin C were significantly higher in whole and parotid saliva of subjects with periodontitis than in healthy controls. Cystatin S, the major salivary cystatin. however was higher in the whole saliva of the healthy group. Whole saliva concentrations of albumin and IgA, originating from sources other than the glandular cells, were not different between healthy and periodontitis subjects and were also not correlated with the typical salivary gland proteins. In conclusion, this study provides additional evidence that the human salivary glands may respond to an inflammatory disease of the oral cavity, periodontitis, by enhanced synthesis of some acinar proteins.     

Specific IgA subclass responses in serum and saliva: a 12-month follow-up study after parenteral booster immunization with tetanus toxoid

Specific IgA subclass antibodies against tetanus toxoid in serum, parotid saliva, and whole saliva were quantified after booster immunization. Samples from 14 healthy individuals were collected before and 1, 6, and 12 months after subcutaneous injection with Duplex ® (0.25 ml tetanus toxoid 30 Lf/mL and diphtheria 7.5 Lf/mL). Samples of whole saliva were also collected after 2 weeks. Specific IgA1 and IgA2 subclass antibodies to tetanus toxoid were quantified by enzyme-linked immunosorbent assay (ELISA). In this quantitative method, chimeric IgA1 and IgA2 antibodies directed against NP (4-hydroxy-3-nitrophenacetyl) were used as standards. Total levels of IgA1 and IgA2 were measured using a nephalometer or ELISA. Immunization with tetanus toxoid resulted in raised mean values of specific IgA1 and IgA2 antibodies against tetanus toxoid in serum after 1 month. Compared with the baseline, the mean value of specific IgA1 antibodies showed a 2.6-fold increase (mean value 10.47 µg/mL) in serum, and that of specific IgA2 antibodies a 2.7-fold increase (mean value 0.93 µg/mL). Specific IgA subclass antibody levels in parotid and whole saliva were unchanged after 1 month. The ratio of specific IgA subclass antibodies to total IgA subclass antibodies was 3 to 10 times higher in parotid saliva compared with whole saliva. In conclusion, subcutaneous booster immunization with tetanus toxoid induced immune responses of both antigen-specific IgA1 and IgA2 subclass antibodies in serum with the same increase, whereas the levels of specific IgA subclass antibodies in secretory fluids were unchanged. The ratio of specific IgA subclass antibodies to immunoglobulins was higher in parotid saliva compared with whole saliva.     

Specific IgA subclass responses in serum and saliva: a 12-month follow-up study after parenteral booster immunization with tetanus toxoid

Specific IgA subclass antibodies against tetanus toxoid in serum, parotid saliva, and whole saliva were quantified after booster immunization. Samples from 14 healthy individuals were collected before and 1, 6, and 12 months after subcutaneous injection with Duplex (0.23 ml tetanus toxoid 30 Lf/mL and diphtheria 7.3 Lf/mL). Samples of whole saliva were also collected after 2 weeks. Specific IgA1 and IgA2 subclass antibodies to tetanus toxoid were quantified by enzyme-linked immunosorbent assay (ELISA). In this quantitative method, chimeric IgA1 and IgA2 antibodies directed against NP (4-hydroxy-3-nitrophenacetyl) were used as standards. Total levels of IgA1 and IgA2 were measured using a nephalometer or ELISA. Immunization with tetanus toxoid resulted in raised mean values of specific IgA1 and IgA2 antibodies against tetanus toxoid in serum after 1 month. Compared with the baseline, the mean value of specific IgA1 antibodies showed a 2.6-fold increase (mean value 10.47 microgram/mL) in serum, and that of specific IgA2 antibodies a 2.7-fold increase (mean value 0.93 microgram/mL). Specific IgA subclass antibody levels in parotid and whole saliva were unchanged after 1 month. The ratio of specific IgA subclass antibodies to total IgA subclass antibodies was 3 to 10 times higher in parotid saliva compared with whole saliva. In conclusion, subcutaneous booster immunization with tetanus toxoid induced immune responses of both antigen-specific IgA1 and IgA2 subclass antibodies in serum with the same increase, whereas the levels of specific IgA subclass antibodies in secretory fluids were unchanged. The ratio of specific IgA subclass antibodies to immunoglobulins was higher in parotid saliva compared with whole saliva.     

Human salivary immunoglobulin and antigen‐specific antibody activity after tonsillectomy

The importance of the lymphoid tissue collectively known as Waldeyer’s ring, which includes the palatine, lingual and nasopharyngeal tonsils, in the induction and contribution of specific antibody responses in human saliva is not clear. The purpose of this study was to determine whether salivary immunoglobulin A (IgA) levels differ in quantity and quality between subjects who have had a tonsillectomy and age, sex and race‐matched controls. Parotid saliva, whole saliva, and blood serum samples were collected from 25 volunteer children who had undergone tonsillectomy (T?) within 6–14 months of sampling and from 25 age, sex and race‐matched controls. The levels of total IgA (and subclasses) in saliva, and of antigen‐specific salivary IgA and serum IgA and IgG antibodies to 4–9 relevant antigens were analyzed by ELISA. No significant difference was observed in the mean total IgA and IgA subclass levels in parotid and whole saliva, although the mean levels for children with a T? were slightly lower. Children with a T? had significantly higher parotid salivary IgA and IgA1 specific/total activity than controls. The total and specific whole saliva IgA and the specific serum IgA or IgG activities were not significantly different from controls. These results indicate an association between the removal of tonsils and increased levels of specific IgA activity in parotid saliva within the first year after a T?.     

Human salivary immunoglobulin and antigen-specific antibody activity after tonsillectomy

The importance of the lymphoid tissue collectively known as Waldeyer's ring, which includes the palatine, lingual and nasopharyngeal tonsils, in the induction and contribution of specific antibody responses in human saliva is not clear. The purpose of this study was to determine whether salivary immunoglobulin A (IgA) levels differ in quantity and quality between subjects who have had a tonsillectomy and age, sex and race-matched controls. Parotid saliva, whole saliva, and blood serum samples were collected from 25 volunteer children who had undergone tonsillectomy (T-) within 6-14 months of sampling and from 25 age, sex and race-matched controls. The levels of total IgA (and subclasses) in saliva, and of antigen-specific salivary IgA and serum IgA and IgG antibodies to 4-9 relevant antigens were analyzed by ELISA. No significant difference was observed in the mean total IgA and IgA subclass levels in parotid and whole saliva, although the mean levels for children with a T- were slightly lower. Children with a T- had significantly higher parotid salivary IgA and IgA1 specific/total activity than controls. The total and specific whole saliva IgA and the specific serum IgA or IgG activities were not significantly different from controls. These results indicate an association between the removal of tonsils and increased levels of specific IgA activity in parotid saliva within the first year after a T-.     

Effects of the antihypertensive drug captopril on human salivary secretion rate and composition

The effects of the antihypertensive drug captopril on salivary secretion rate and composition was evaluated in 24 healthy adults (18–46 yr) according to a double-blind, cross-over design. Unstimulated and paraffin-chewing stimulated whole saliva and 3% citric acid stimulated parotid and submandibtilar-sublingual (SM-SL) secretion were collected at 10.30 a.m. (about 2h after intake of breakfast) on day 0 (baseline values), day 1 (experimental acute values) and day 7 (experimental chronic values) in each treatment period. In 8 of the subjects, also morning samples were collected at 7.30 a.m., with the test subjects in a fasting condition. Whole saliva was assessed for flow rate and for concentrations of sodium, potassium, chloride, calcium and phosphate. In addition, parotid and SM-SL secretion were assessed for concentrations of total protein, hexosamine. sialic acid, lactoferrin and salivary IgA and for activities of amylase. lysozyme and salivary peroxidase. During treatment with the angiotensin converting enzyme inhibitor captopril, the secretion rates tended to increase for unstimulated and paraffin-chewing stimulated whole saliva and for parotid secretion. For salivary composition, no alterations were observed in any of the collected secretions.     

The relationship between IgA antibodies to Streptococcus mutans antigens in human saliva and breast milk and the numbers of indigenous oral Streptococcus mutans

The influence of indigenous Streptococcus mutans on naturally-occurring levels of IgA antibodies was studied in 42 lactating females. Breast milk, parotid and whole-saliva samples were collected and analysed by the ELISA method for IgA antibodies, reacting with antigens from Strep. mutans. All salivas and breast milk showed IgA antibody activity to five antigenic preparations from Strep. mutans and to a pool of Escherichia coli antigens. No correlation was observed between the IgA antibody level in breast milk and that in saliva. The total IgA in breast milk was, however, considerably higher than in the salivas. In subjects with active caries and subjects with high DMFS scores, there was a tendency toward lower levels of IgA antibodies in whole saliva than in subjects with low caries experience. The levels of specific IgA antibodies in saliva did not reflect the amount of indigenous Strep. mutans present in the mouth at the time of sampling.     

Effects of a beta-blocking agent, timolol maleate, on saliva in healthy volunteers

The effects of timolol maleate on the secretion and composition of human saliva were studied in vivo. Eight healthy volunteers received orally 10 mg timolol maleate. Stimulated parotid saliva samples, resting whole saliva samples, and blood samples were collected immediately before and four times after the drug intake at intervals of 1 h. The levels of total protein, lysozyme, IgA, IgG and IgM, salivary peroxidase, myeloperoxidase, lactoferrin, amylase, thiocyanate (SCN-), and hypothiocyanite (OSCN-) were analyzed from saliva samples. Drug levels were measured both from parotid saliva and blood samples. Results were compared to the analyses of the samples collected in a similar way but without administration of any drugs. Decreased levels of total protein, lactoferrin, amylase, and salivary peroxidase were observed in parotid saliva after a single oral dose of timolol maleate. No such decrease was found in lysozyme, myeloperoxidase, SCN-, OSCN-, or immunoglobulins. Salivary flow rate was not significantly changed after drug intake. The results suggest that the beta-blocking drug may cause qualitative changes in the composition of saliva by inhibiting the synthesis and/or release of acinar proteins.     

Effects of a β-blocking agent, timolol maleate, on saliva in healthy volunteers

Abstract — The effects of timolol maleate on the secretion and composition of human saliva were studied in vivo. Eight healthy volunteers received orally 10 mg timolol maleate. Stimulated parotid saliva samples, resting whole saliva samples, and blood samples were collected immediately before and four times after the drug intake at intervals of 1 h. The levels of total protein, lysozyme, IgA, IgG and IgM, salivary peroxidase, myeloperoxidase, lactoferrin, amylase, thiocyanate (SCN^-), and hypothiocyanite (OSCN^-) were analyzed from saliva samples. Drug levels were measured both from parotid saliva and blood samples. Results were compared to the analyses of the samples collected in a similar way but without administration of any drugs. Decreased levels of total protein, lactoferrin, amylase, and salivary peroxidase were observed in parotid saliva after a single oral dose of timolol maleate. No such decrease was found in lysozyme, myeloperoxidase, SCN-, OSCN-, or immunoglobulins. Salivary flow rate was not significantly changed after drug intake. The results suggest that the β-blocking drug may cause qualitative changes in the composition of saliva by inhibiting the synthesis and/or release of acinar proteins.     

Change from mixed diet to lactovegetarian diet: influence on IgA levels in blood and saliva

IgA concentrations in human plasma, and whole and parotid saliva were measured before and 3 months after a shift to a lactovegetarian diet in 20 volunteers (four men and 16 women, mean age 44 yr, range 27–61). The major dietary trends observed were an increased intake of berries and other fruits, vegetables, and dairy products, and a decreased intake of fish, eggs, and meat; biscuits and buns; sweets; alcoholic beverages; coffee; and tea. The consumption of meat, fish, and eggs decreased to zero, showing that the participants had adopted a lactovegetarian diet. There was a decrease in fat, protein, sucrose, and alcohol intake and an increase in total carbohydrate and fiber intake. There was no significant change in energy, retinol equivalent, or zinc intake. Despite this change in diet, no significant changes were observed between the mixed diet period and the vegetarian diet period in IgA in plasma, 253±52 and 264±55; whole saliva, 2.5±0.4 and 2.4±0.4; or parotid saliva, 0.88±0.22 and 0.90±0.20 (mg/100 ml, mean values, 95% confidence interval). Moreover, the diet change did not after the secretion rate in whole and parotid saliva, the secretion rate of IgA in whole and parotid saliva, or the protein content of whole saliva. However, the protein content of parotid saliva increased significantly. Thus, this major diet change was apparently not drastic enough or sustained long enough to cause a change in IgA levels.     

Assessing the levels of immunoglobulins in the saliva of diabetic individuals with periodontitis using checkerboard immunodetection

BACKGROUND: Current methods for determining salivary antibodies are cumbersome for large-scale screenings. OBJECTIVES: To test checkerboard immunodetection for monitoring salivary antibodies and to profile them in diabetic individuals with periodontitis. METHODS: Salivary anti-Porphyromonas gingivalis, anti-Actinobacillus actinomycetemcomitans and total IgA levels of 10 individuals were compared using checkerboard immunoblotting and enzyme-linked immunosorbent assay (ELISA). RESULTS: Close correlation between both methods was found in anti-P. gingivalis IgA and total IgA, but not in anti-A. actinomycetemcomitans IgA, because of high background levels in ELISA. Thereafter, checkerboard immunodetection was used to compare salivary antibodies of 20 adult type II diabetic with 32 non-diabetic individuals with (n=22) or without (n=10) periodontitis. Patients with periodontitis (regardless of their diabetic condition) expressed increased levels of total IgA in both whole and parotid saliva, but reduced levels of anti-A. actinomycetemcomitans IgA in whole saliva. Consequently, the proportion of anti-A. actinomycetemcomitans IgA in the total IgA was lower in saliva of patients with periodontitis compared with healthy controls. CONCLUSIONS: Checkerboard immunodetection was reliable and economical for screening saliva samples for multiple antibody reactions. Our results support previous reports which suggested that patients with periodontitis are able to secrete high levels of salivary Ig, but are hampered in targeting their salivary response toward A. actinomycetemcomitans.