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-.     

Salivary and serum antibodies to gliadin in the diagnosis of celiac disease

Salivary IgA and serum IgA and IgG antibodies to crude gliadin and alpha-gliadin were measured in adult patients with untreated celiac disease, ulcerative colitis, Crohn's disease and normal controls. Antibody levels in saliva and serum in untreated celiac disease were significantly higher than in other groups. Alpha-gliadin antibodies appeared to be a better discriminator for serum but not for saliva. The assay of salivary IgA antibodies to gliadin offers a non-invasive test which would be particularly useful in the investigation of celiac disease and for monitoring compliance with a gluten-free diet.     

Saliva increases serum IgG retention on Streptococcus mutans

The purpose of this investigation was to determine if saliva would affect the retention of serum antibodies to S. mutans. A quantitative enzyme-linked immunosorbent assay (ELISA) was used to estimate total IgM, IgG and IgA after applications of whole saliva and absorbed serum to equal but separate aliquots of S. mutans. Total antibodies were also estimated after the sequential application of saliva and adsorbed serum to the same aliquot of S. mutans. Significantly more IgG, but not IgM or IgA, was retained on saliva-treated cells than on untreated cells. IgG retention was greatly diminished when saliva was pre-ab-sorbed with S. mutans but Streptococcus sanguis was less effective. Most subjects, regardless of caries experience, had IgG that would be retained by saliva-treated cells but saliva from caries-resistant subjects promoted IgG retention significantly more than saliva from susceptible subjects.     

Fluctuations in crevicular and salivary anti-A viscosus antibody levels in response to treatment of gingivitis

Abstract Experimental gingivitis studies support a pathogenic rôle for Actinomyces viscosus because of its numerical predominance in disease-associated plaques. The aims of the present investigation were to quantify specific crevicular IgG against A. viscosus before and after conventional gingivitis treatment and to determine whether salivary IgA and IgG against A. viscosus and A. noeslundii would be affected concomitantly. 6 subjects with generalized gingivitis were selected. Examinations were made before and after treatment and included collection of unstimulated saliva, paraffin-stimulated saliva and crevicular material as well as measurements of clinical parameters. The immunoglobulins were estimated by an ELISA assay using whole bacterial cells as antigen. Crevicular IgG against A. viscosus WVU 627 was demonstrated in pre- and post-treatment samples with a tendency towards increased values in the post-treatment samples. Salivary IgA and IgG against A. viscosus were also demonstrated in pre- and post-treatment samples. There were tendencies towards increased IgA values for paraffin-stimulated saliva and increased IgG values for unstimulated saliva in the post-treatment samples. Salivary IgA and IgG values against A. naeslundii ATCC 12104 were either not detected or barely detectable in both pre- and post-treatment samples. A. naeslundii B 74 IgG values were also rather low. As for A. viscosus WVU 627. anti-B 74 IgA values demonstrated a post-treatment increase for most subjects, especially for unstimulated saliva for which all post-treatment values were elevated. It is interesting to note that saliva samples showed changes similar to crevicular material, considering that salivary IgA is most likely derived from a different source. Together, elevated crevicular and salivary antibody concentrations might account for some of the beneficial effects of periodontal therapy by scaling.     

Salivary and serum antibody response to Streptococcus mutans antigens in humans

Humoral immunity against Streptococcus mutans infection was analyzed in caries-active and caries-free young adults by immunoblotting. All volunteers from both groups had detectable salivary immunoglobulin A (IgA) and serum IgG antibodies, with similar profiles. They could be classified on the basis of relative intensity of the immunoblot bands into categories of high or low responders. Common protein antigens with molecular weight ranging from approximately 45 to 190 kDa could be found either extracellularly or associated with the cell wall of S. mutans cultured in vitro. The predominant reactive antigens recognized by both IgA and IgG were of proteins around 63 and 60 kDa. Detection of IgA antibodies to the various antigens of S. mutans in individual saliva samples did not always correlate with serum IgG antibody profiles. In addition, distinct bands, which reacted preferentially with either IgA or IgG, could be detected by antibodies from specific subjects. Differential reactivities of salivary IgA and serum IgG antibodies to two, cell-wall associated protein antigens around 33 and 36 kDa were found in caries-active and caries-free young adults; 30.8% of caries-free subjects and 12% of caries-active subjects (P < 0.01) exhibited detectable antibody response to these antigens. This difference was not attributable to variations in antibody levels, since antibody response to these proteins were still detectable in some caries-free but not caries-active individuals whose levels of antibodies to other antigens were low. Thus, a new antibody profile which correlates with dental caries disease activity has been identified in a selected population. Differences in mucosal and systemic immune responses to S. mutans seem to be both antigen and host dependent.     

Serum and salivary antibodies to a mycobacterial 65-kDa stress protein are elevated in HIV-positive patients and modified by oral candidiasis

Serum immunoglobulin G (IgG) and IgA, and salivary IgA antibodies to a mycobacterial stress protein (mSP65) were determined in human immunodeficiency virus (HIV)-positive patients, acquired immunodeficiency syndrome (AIDS) patients and HIV-negative controls with or without oral candidiasis. Serum IgG antibodies were elevated in patients with HIV infection and AIDS and especially in subjects with candidiasis compared with controls (P < 0.02, P < 0.005). This was not apparent with serum IgA. In the absence of candidiasis, salivary IgA antibodies were elevated in HIV-positive patients compared with AIDS (P < 0.005) patients and healthy controls (P = 0.001). The relative avidity of serum IgG antibodies to mSP65 in controls with candidiasis was lower than healthy controls (P < 0.0001). In saliva there was a decrease in the relative avidity of IgA antibodies in AIDS patients with candidiasis compared with HIV patients (P < 0.03). In patients without candidiasis, the relative avidity was higher in HIV patients than healthy controls (P = 0.02). The results suggest that HIV infection leads to raised serum and salivary antibodies to heat shock proteins. Concurrent Candida infection may modify both the titer and relative avidity differently for serum and saliva.     

Specific antibodies against Actinobacillus actinomycetemcomitans in serum and saliva of patients with advanced periodontitis

The aim of the present study was to discover any possible correlation between specific antibodies against Actinobacillus actinomycetemcomitans (A.a.) in serum and saliva. The test group consisted of 38 patients aged 31–68 yr (mean 49) with advanced periodontitis. Twenty-nine subjects aged 23–67 yr, without periodontal destruction, formed a control group with a reference level of specific salivary antibodies against A.a. A subgingival plaque sample for culturing A.a. , a specimen of stimulated whole saliva, and a sample of venous blood were taken from each subject of the test group. Specific IgG and IgA antibodies against A.a. were determined from serum and stimulated whole saliva by means of the ELISA test. Fifteen of the patients (39%) had cultivable A.a. Six of the 15 A.a. culture-positive patients and one of the 29 reference subjects exhibited very high antibody titers against A.a. in saliva. Specific IgG and IgA antibodies in saliva correlated highly significantly with the corresponding antibody values in serum among the patients in the test group. It was concluded that among patients with severe adult periodontitis, the less invasive saliva sample has a diagnostic value equal to that of the serum sample concerning specific antibodies against A.a.     

Function of anti-Strepfococcus mutans antibodies: inhibition of virulence factors and enzyme neutralization

The levels of parotid salivary IgA and serum IgG antibodies from dental caries-resistant (CR) and caries-susceptible (CS) individuals to Streptococcus mutans antigens were determined. In general, the levels of salivary IgA and serum IgG antibodies to S. mutans antigens were significantly higher in CR subjects than in CS individuals. There were significantly higher levels of IgA2, but not IgA1, salivary antibodies to S. mutans whole cells in CR subjects than in CS individuals. These results led us to investigate the functional effects parotid saliva and sera containing these antibodies had on several factors associated with S. mutans virulence. Parotid saliva and sera from CR subjects significantly inhibited S. mutans growth, adherence, acid production, glucosyltransferase and glucose-phosphotransferase activities to a greater extent than saliva and sera from CS individuals. The data suggest that neutralization of S. mutans enzymes and inhibition of S. mutans virulence factors by saliva and serum may be responsible for the lower numbers of carious lesions in CR subjects.     

Serum and salivary antibodies to Streptococcus mutans in relation to the development and treatment of human dental caries

Antibodies to Streptococcus mutans and Streptococcus sanguis were examined in samples of serum and parotid saliva from 96 subjects, aged 18–24. Subjects were divided into groups based on the concept that any natural immunity would be best revealed by comparing subjects of low caries experience with subjects of high caries experience, and analysing separately subjects with carious lesions at the time of examination. Low caries experience was associated with significantly greater serum IgG and IgM antibodies but lower salivary IgA antibodies to Strep. mutans than high caries experience. In subjects with carious lesions serum IgG antibodies to Strep. mutans were significantly greater than in the matched high caries experience group, but salivary antibodies were lower. No differences in the antibody levels to Strep. sanguis were detected in the three groups. Sequential studies revealed that the development of caries was associated with a rise in serum IgG and IgM antibodies to Strep. mutans, but not to Strep. sanguis. Treatment of caries was associated with a fall in serum antibodies to Strep. mutans but a rise in salivary antibodies. The results suggest that Strep. mutans is closely associated with caries in man, but that Strep. sanguis is not. It is suggested that, in man, naturally induced serum IgG antibodies are associated with protection against caries, but that antibodies of the IgA class in serum or parotid saliva are not associated with protection. Serum IgG antibodies to Strep. mutans or Strep. sanguis showed an inverse relationship with salivary IgA antibodies, and changes in the salivary antibody titre were negatively correlated with changes in the serum IgG antibody titre.     

Salivary IgG,a parameter of periodontal disease activity?

The concentration of salivary IgG and IgA and the levels of salivary IgG and IgA antibodies to Actinobacillus actinomycetemcomitans Y4 were measured by ELISA in 205 persons including patients with juvenile and adult periodontitis as well as healthy subjects. Compared to the concentration observed in subjects with a healthy periodontium, a significantly increased concentration of salivary IgG was found in 34% of the patients with moderate adult periodontitis and in 57% of the patients with severe adult periodontitis. The level of salivary IgA was less influenced by the periodontal condition. The level of salivary IgG antibody to A. actinomycetemcomitans was significantly elevated in 55% of the patients with untreated juvenile periodontitis and in 28% of the patients treated for JP. 28% of the patients with adult periodontitis had a significantly elevated level of IgG antibody to A. actinomycetemcomitans Y4. Significantly elevated levels of IgA antibody to this bacteria was found less frequently, 27% in untreated JP, 20% in treated JP and 17% in adult periodontitis.     

Salivary immunoglobulin A antibodies to gp41 in human immunodeficiency virus-seropositive patients: lack of correlation with disease progression

Mucous membranes are the main route of transmission of human immunodeficiency virus (HIV). Interestingly, some viral inhibitory activities have been found in saliva. The purpose of this study was to determine the level of salivary immunoglobulin A (IgA) antibodies to gp41 in HIV+ patients at various disease stages to identify whether gp41 was able to induce vigorous humoral responses. Unstimulated saliva samples were obtained from three groups of subjects (n=37): group A (HIV-), group B (HIV+, CD4+ <200/mm3), and group C (HIV+, CD4+ >200/mm3). IgA antibody levels to purified gp41 were determined by enzyme-linked immunosorbent assay (ELISA). Western blot analyses were performed using HIV+ saliva to confirm IgA reactivity to gp41. ELISA demonstrated that HIV+ subjects had higher IgA antibody to gp41 than HIV- individuals. No significant differences were noted between HIV+, CD4+ <200/mm3 and CD4+ >200/mm3 subjects. High (81.25%) IgA reactivity to gp41 was demonstrated by Western blotting of saliva from all HIV+ individuals. In conclusion, gp41 responses are important in the HIV disease process, as indicated by the high IgA levels and gp41 reactivity in saliva of HIV+ patients.     

Detection of salivary antibodies to crude antigens of <Emphasis Type="Italic">Opisthorchis viverrini</Emphasis> in opisthorchiasis and cholangiocarcinoma patients

Opisthorchis viverrini (O. viverrini; known as human liver fluke) is a major health problem in the northeastern region of Thailand. Infection with O. viverrini is the cause of hepatobiliary disease and cholangiocarcinoma (CCA). Previous studies demonstrated specific antibodies to crude O. viverrini antigens in serum from O. viverrini-infected patients. However, no studies have measured specific antibodies to O. viverrini antigens in saliva from patients with opisthorchiasis and CCA. The objective of the study was to detect specific antibodies to crude O. viverrini antigens in saliva from patients with opisthorchiasis and CCA, and to evaluate their use for diagnosis of O. viverrini infection. Saliva samples from 23 control subjects, 30 opisthorchiasis patients, and 38 CCA patients were collected. ELISA was established for detection of salivary IgA and IgG to crude O. viverrini antigens. ANOVA was used to compare salivary IgA and IgG levels among groups. Salivary IgA to crude O. viverrini antigens in CCA patients was significantly higher than controls (p = 0.007). Salivary IgG in CCA patients was significantly higher than opisthorchiasis patients and controls (p = 0.010 and p < 0.001, respectively). The cut-off value from salivary IgG test demonstrated higher accuracy for positivity of O. viverrini infection than salivary IgA. In conclusion, specific antibodies to crude O. viverrini antigens were detected in saliva of patients with opisthorchiasis and CCA. Salivary antibodies reflect serum immune response to O. viverrini infection, and salivary IgG tends to be a good candidate for diagnosis of O. viverrini infection.     

Serum and salivary antibodies to a mycobacterial 65‐kDa stress protein are elevated in HIV‐positive patients and modified by oral candidiasis

Serum immunoglobulin G (IgG) and IgA, and salivary IgA antibodies to a mycobacterial stress protein (mSP65) were determined in human immunodeficiency virus (HIV)–positive patients, acquired immunodeficiency syndrome (AIDS) patients and HIV‐negative controls with or without oral candidiasis. Serum IgG antibodies were elevated in patients with HIV infection and AIDS and especially in subjects with candidiasis compared with controls (P<0.02, P<0.005). This was not apparent with serum IgA. In the absence of candidiasis, salivary IgA antibodies were elevated in HIV‐positive patients compared with AIDS (P<0.005) patients and healthy controls (P=0.001). The relative avidity of serum IgG antibodies to mSP65 in controls with candidiasis was lower than healthy controls (P<0.0001). In saliva there was a decrease in the relative avidity of IgA antibodies in AIDS patients with candidiasis compared with HIV patients (P< 0.03). In patients without candidiasis, the relative avidity was higher in HIV patients than healthy controls (P=0.02). The results suggest that HIV infection leads to raised serum and salivary antibodies to heat shock proteins. Concurrent Candida infection may modify both the titer and relative avidity differently for serum and saliva.     

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.     

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.     

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.     

Studies on the induction of the humoral immune responses to Bacteroides gingivalis fimbrial antigen in mice

Serum and salivary antibody responses to Bacteroides gingivalis fimbriae administered either orally or subcutaneously (s.c.) with or without an adjuvant in various strains of mice were examined in this study. Following results were obtained. 1) Oral administration of B. gingivalis fimbriae with GM-53 as an adjuvant in liposomes, but not in Tris-HCl buffer, definitely enhanced the fimbriae-specific IgG responses, mainly IgG1 followed by IgG2b, IgG2a and IgG3 in serum and IgA response in saliva of BALB/c mice. On the other hand, s.c. injection of fimbriae with GM-53 or MDP-Lys (L18) also raised the fimbriae-specific IgG followed by IgA and IgM responses in serum, and both IgA and IgG responses in saliva of BALB/c mice. Oral immunization was less effective than s.c. injection in terms of the production of serum antibody in the mice. However, the level of salivary antibody of mice injected s.c. was similar to that of mice immunized orally. 2) High anti-fimbriae antibodies in serum were maintained in BALB/c mice immunized orally with fimbriae and GM-53 in liposomes for approximately 7 months after the primary immunizations. Oral administration also induced and held the fimbriae-specific IgA response in saliva for at least 6 months after the primary immunizations. The levels of fimbriae-specific IgA in saliva after the second boosters on days 123 and 124 were higher than those after the primary ones on days 27 and 28. 3) Among various strains of mice immunized orally with fimbriae and GM-53 in liposomes, BALB/c and DBA/2 mice (H-2d) significantly produced high levels of both serum IgG and salivary IgA antibodies specific for fimbriae. Furthermore, B10.D2 mice (H-2d) were responders followed by B10.BR (H-2k), while C57BL/10 mice (B10, H-2b) were low responders to the fimbriae. These results show that the combined use of fimbriae together with an adjuvant results in a sharply increased IgA antibody response in saliva and a predominantly stimulated IgG antibody in serum, and it was suggested that these responses are restricted by H-2 haplotype.     

Secretory and serum antibodies against Streptococcus lactis, Streptococcus thermophilus, and Lactobacillus bulgaricus in relation to ingestion of fermented milk products

Serum, saliva, and urine were analyzed for the presence of IgA, IgG, and IgM antibodies reactive with the yoghurt bacteria Streptococcus thermophilus and Lactobacillus bulgaricus. A comparison was made between four subjects who frequently ate yoghurt and four subjects who never ate yoghurt. Salivary IgA and serum IgG activity against the milk-fermenting bacterium S. lactis was studied in five other subjects before, during, and after a period of ingestion of a fermented milk product, filmj?lk. All analyses were carried out by an enzyme-linked immunosorbent assay method. Antibody activity against the yoghurt bacteria was found in saliva, serum, and urine. No difference in antibody activity between yoghurt eaters and non-yoghurt eaters was measured for salivary IgA, but for serum IgG a lower activity against S. thermophilus was present among the yoghurt eaters. Antibody activity against S. lactis was present already before the ingestion of filmj?lk began, and the activity was not altered during the period of ingestion. It is concluded that in adult subjects, the ingestion of milk-fermenting bacteria does not result in a significant change in the antibody activity against these bacteria.     

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)