[A study of secretory IgA antibody titers for Chlamydia trachomatis in prostatic secretion of chronic prostatitis]

In order to study the correlation between chronic prostatitis and C. trachomatis, IgA and IgG antibody titers for C. trachomatis were measured in serum and prostatic secretion of cases of chronic prostatitis. IgA antibody titers have higher tendency in prostatic secretion than in serum. The other side, IgG antibody titers have higher tendency in serum than in prostatic secretion. This result suggested IgA antigen was reacted in local immunological response in prostatic gland. Subsequently, in order to confirm that IgA antibody in prostatic secretion is formed from secretory IgA antibody mainly, IgA antibody titers were compared with secretory IgA antibody titers. That results was considered that many cases with high IgA titers had high secretory IgA titers. The fact suggested in cases of C. trachomatis prostatitis, IgA antibody was mainly formed from secretory IgA antibody in prostatic secretion.

Both IgA subclasses are reduced in parotid saliva from patients with AIDS

Secretory IgA (SIgA), the isotypes IgA1 and IgA2, and IgM were measured by ELISA in stimulated parotid saliva from patients with AIDS (n = 16), subjects with asymptomatic HIV infection (n = 28), and HIV-seronegative healthy controls (n = 19). SIgA was significantly reduced in the AIDS group (10.4 micrograms/ml) compared with the asymptomatic HIV-infected subjects (17.1 micrograms/ml) and the controls (23.0 micrograms/ml). This decrease comprised both IgA1 and IgA2 to a similar extent on a relative basis. The SIgA decrease in AIDS patients was in striking contrast to their serum IgA level, which was significantly increased (6.9 g/l) compared with the asymptomatic HIV-infected subjects (2.9 g/l) as well as the controls (2.8 g/l). Low parotid output of SIgA in patients with HIV infection was associated with low numbers of CD4+ lymphocytes in peripheral blood as well as the presence of oral infections. The parotid output of IgM was similar in all groups. A low level of SIgA in the external secretions of patients with AIDS may well contribute to their frequent mucosal infections of opportunistic microorganisms.

[A radioimmunological method for determining IgA-class antimeningococcal secretory antibodies in human saliva]

The data on the content of secretory IgA antibodies to group A Neisseria meningitidis protein antigen in the saliva of persons, both having had contact with N. meningitidis culture and having had no such contact, are presented. The results were obtained by the method of radioimmunoassay, developed specially for the determination of N. meningitidis protein antigen.

Breast feeding modifies production of SIgA cow's milk-antibodies in infants

One hundred and fifty-eight healthy mature newborns were divided into 3 groups according to their risk of allergy: Group A, no risk (n = 62), group B, low risk (n = 30) and Group C, high risk (n = 66). Saliva was collected at birth and after 3 and 6 months. SIgA anti-casein and anti-beta-lactoglobulin were determined by a direct ELISA technique. The highest concentrations of secretory antibodies were measured after birth. After 3 months, breast fed infants had lower salivary SIgA anti-casein concentrations than the group receiving cow's milk (p less than 0.01). The effect of breast-feeding was seen even after a nursing period of only 3 weeks. Infants without risk of allergy fed cow's milk exclusively had higher SIgA anti-casein (p less than 0.03) and anti-beta-lactoglobulin concentrations than low risk infants at the age of 6 months. These data show a modifying effect of breast feeding on salivary SIgA production against cow's milk protein.

Reduced concentration of secretory IgA indicates changes of local immunity in children with adenoid hyperplasia and secretory otitis media

Children with adenoid hyperplasia and secretory otitis media show significantly lower immunoglobulin A (sIgA) concentrations in their saliva compared to matched controls. Salivary albumin and cortisol levels do not differ in both groups. Changes in local immunity, dilution or stress as possible factors for the reduction of sIgA concentrations are discussed.

The role of secretory immunity in hepatitis A virus infection

Because the role of intestinal immunity remains uncertain in hepatitis A, samples of feces and saliva from infected primates and humans were tested for virus neutralizing activity. Only two of eight owl monkeys infected by the intragastric route developed neutralizing antibody detectable in extracts of feces collected up to 88 days after viral challenge, although serum neutralizing antibody was present in all monkeys by day 33. Similarly, neutralizing antibody was detected in fecal extracts from none of three experimentally infected human volunteers and only 1 of 15 naturally infected humans. The single positive human specimen contained occult blood. Only 2 of 19 saliva samples from naturally infected humans had significant viral neutralizing activity. In contrast, neutralizing antibody to type 2 poliovirus was present in most human fecal or saliva specimens tested. These data suggest that intestinal immunity does not play a significant role in protection against hepatitis A.

Differences in level and avidity of secretory IgA antibodies in breast milk of Swedish, Indian and Japanese mothers to soybean protein

Colostrum was collected from Swedish, Indian and Japanese mothers. The samples were as a mean, collected 4.00-4.25 days after delivery of term infants. The level of specific IgA antibody to 2S, 7S and crude soybean antigen were measured by the enzyme-linked immunosorbent assay (ELISA). The avidity of the IgA antibodies to 7S soybean antigen was also measured with an ELISA system using different molarities of potassium thiocyanate for elution of the specific IgA antibody from solid phase-bound antigen. The level of specific IgA antibody to 7S and crude soybean antigen in the milk of the Indian mothers was significantly higher than in the milk of the Japanese mothers (p less than or equal to 0.01). In contrast, the avidity expressed as the molarity of KSCN for 50% elution of IgA antibody to 7S soybean antigen in the milk of the Japanese mothers was significantly higher than in the milk of the Indian mothers (p less than 0.01).

[Determination of 11S IgA in nasal secretions in the monitoring of local immunomodulating therapy]

Twenty pediatric patients with recurrent infectious diseases of the upper respiratory tract (tonsillitis, adenotonsillitis with or without involvement of the ear and/or lower respiratory tract) were studied. An immunological assay of the nasal secretum was performed at time of diagnosis and following treatment with a local immunomodulator drug, administered by spray. The 7S, 11S IgA and albumin rates were evaluated. The authors emphasize the importance of SIgA in mucose defense mechanisms as well as the need for a selective method for determining the 11S IgA level. An original method for immuno-isoelectrofocusing (IIEF) determination was employed in the present study. After treatment a significant increase in 11S IgA level was observed, especially in those patients with a significant basal SIGA deficit. The authors describe details of the technique for determination and discuss the results.

Serum levels of secretory IgA in ankylosing spondylitis

An ELISA test was performed in order to measure the serum levels of secretory IgA (sIgA) in 51 patients with ankylosing spondylitis (AS) and 30 healthy controls. Raised values of sIgA were found in AS patients compared to controls. Patients with active disease, defined by clinical criteria, showed a significant elevation of serum sIgA compared to healthy controls (p = 0.03) or to patients with inactive disease (p = 0.02). A positive correlation between total serum IgA and sIgA was found (p = 0.001). Our findings further support the role of the mucosal stimulation in the pathogenesis of AS.

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.

Ragweed-specific IgA in nasal lavage fluid of ragweed-sensitive allergic rhinitis patients: increase during the pollen season

Because the secretions of asthma and rhinitis contain toxic eosinophil granule proteins and because secretory IgA is the most potent immunoglobulin stimulus for eosinophil degranulation, we measured eosinophil-derived neurotoxin and ragweed-specific IgA and IgE antibodies in nasal lavage before and during the ragweed pollen season in 44 hay fever patients. We found IgA antibody in nanogram/milliliter concentrations before the season and rising 20-fold by the end of the season. IgE antibody was present in picogram/milliliter concentrations and did not change. Eosinophils and eosinophil-derived neurotoxin also increased. We conclude that IgA is the predominant antibody in allergic nasal secretions and increases with allergen exposure. The hypothesis that secretory IgA antibody-allergen complexes contributes to allergic inflammation by stimulating eosinophil degranulation warrants further study.

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.

Diagnosis of intestinal amebiasis using salivary IgA antibody detection

This investigation sought to determine whether detection of salivary IgA antibodies to Entamoeba histolytica could identify intestinal amebic infections among 223 school children. Four groups of children were identified through coproparasitoscopic examination: E. histolytica as other parasites only (20%); and parasite-free (25%). The diagnostic accuracy of salivary IgA antibodies to an E. histolytica membrane extract was 91.5% (sensitivity, 85%; specificity, 98%), maintaining high predictive value at different prevalences. Also, a positive correlation (r = .753, P less than .001) was observed between fecal E. histolytica membrane antigen levels and salivary IgA antibody activity. Measurement of IgA antibodies in saliva may be useful in diagnosing intestinal infections with E. histolytica within a wide range of prevalences. Moreover, sampling of saliva may be a useful non invasive test for immunoepidemiologic surveys.

[Basic investigation of saliva SIgA]

Saliva, which contributes to maintaining health in the oral environment, is affected by the physiological functions of the organism and their condition. Dental caries and periodontosis, both of which are oral diseases with frequent occurrence, require the presence of bacteria to occur. SIgA (secretory IgA), an immune globulin that is found in large quantities in substances secreted during salivation, has an antibacterial action. Thus, in conducting a basic investigation on the relationship between these factors, the author investigated what effect the speed of saliva secretion, a physiological factor of the saliva component, has on the SIgA value. Results showed that, regarding the relationship between the salivary SIgA value and the speed of salivary secretion, a negative correlation exists although this is weak in terms of relevance. The fact that the correlation displayed a tendency toward scattering indicates a need to pay attention when measuring the elements in the saliva to those factors that evidently have an effect on the composition of the saliva.

Dental caries in congenitally athymic rats

The importance of the immune response in dental infection was evaluated in heterozygous (rnu/+) normal and homozygous (rnu/rnu) congenitally athymic "nude" Rowett rats. Animals of both types were infected, or immunized and infected, with mutans streptococci (Streptococcus sobrinus strain 6715). The mean numbers of S. sobrinus cells recovered from the nude rats were higher than those from comparable (immune/nonimmune) normal rats in 10 of 12 possible comparisons. Also, S. sobrinus constituted a greater percentage of the total streptococci in the nude rats compared with normal animals (6 of 6 possible comparisons). Antibody to S. sobrinus whole cells or to S. sobrinus glucosyltransferase from nude rats in serum or in saliva was significantly lower (or absent) than that of comparable normal rats. This was seen after infection, but was most pronounced after immunization (and infection). Dental caries was also significantly elevated in the congenitally athymic animals. Immunologic deficiency of congenitally athymic rats can lead to a greater infection level with mutans streptococci and increased dental caries.

Appraisal of gut lavage in the study of intestinal humoral immunity

Direct investigation of intestinal humoral immunity requires collection of intestinal secretions or mucosal biopsy specimens, or both. A non-invasive technique of gut lavage, with a polyethyleneglycol electrolyte lavage solution as a means of collecting intestinal secretions for immunoglobulin and antibody studies, was evaluated. Fifty patients were studied--25 immunologically normal patients or volunteers, 15 patients with untreated coeliac disease, and 10 patients with active Crohn's disease. Protease inhibitors were added promptly to samples to prevent proteolysis of immunoglobulin content. Treated lavage samples were assayed by enzyme linked immunosorbent assay for immunoglobulin and antibody content. Studies of serial lavage specimens showed that early, faecally contaminated specimens contained negligible quantities of immunoglobulin, but once the specimens became clear a steady state was reached, with little variation in immunoglobulin content between serial specimens and with a uniform dilution (around 20%) of the ingested polyethyleneglycol. Gut lavage fluid IgA was predominantly secretory, comprising 92%, 81.6%, and 76.7% respectively of the total IgA gut lavage fluid content in the control, coeliac, and Crohn's groups. High values of total IgM and IgA and IgM antigliadin antibodies were detected in the coeliac group, and high values of IgG in the Crohn's disease group. This method of gut lavage is not only an effective bowel cleanser, but also a noninvasive means of obtaining intestinal secretions for the study of humoral immunity in gastrointestinal disease.

Influence of ocular surface antigen on the postnatal accumulation of immunoglobulin-containing cells in the rat lacrimal gland

The objective of the present study was to determine whether antigenic presence on the ocular surface might directly influence the development or expression of the lacrimal secretory immune system. Experiments were designed to: (i) analyse the temporal accumulation of IgA-, IgG- and IgM-containing cells in lacrimal tissue during postnatal development (6-27 days of age); (ii) examine whether prevention of antigenic exposure to the ocular surface by unilateral tarsorrhaphy might inhibit lymphocyte immigration into the ipsilateral gland during development; and (iii) assess whether a non-invasive antigen, after placement on the ocular surface of infant or adult rats, undergoes retrograde transfer to the lacrimal gland. Our results demonstrated that: (i) the accumulation of IgA-, IgG- and IgM-containing cells in lacrimal tissue was most pronounced during the 6-day period after eyelid opening (15 days of age). The pattern of appearance of these Ig-containing cells, which were predominantly IgA-positive, was identical in both left and right lacrimal glands. (ii) Closure of the left lid by tarsorrhaphy from 10 to 18 days of age had no effect on the accumulation of IgA-, IgG- and IgM-containing cells in the left lacrimal tissue compared to cell numbers in the right gland. (iii) Following placement of radiolabelled albumin on the ocular surface, antigen was almost completely cleared within 1-2 hr. Analysis of lacrimal glands showed no significant accumulation of radioactivity at any time-point, either in the presence or absence of ocular inflammation. In contrast, up to 17.8% of radioactivity was found in the stomach 1-2 hr following topical antigen application. Overall, our results show that a rapid development of the lacrimal secretory immune system occurs between 15 and 21 days of age. This process does not appear to be dependent upon local antigenic stimulation. In addition, our findings indicate that a non-invasive antigen, when applied to the ocular surface, does not undergo retrograde transfer to the lacrimal gland. Instead, antigen appears to be cleared primarily through the gastrointestinal tract.

Detection of secretory IgM in tears of IgA deficient individuals

Tears from normal (n = 5) and serum IgA deficient (n = 3) individuals were investigated for the presence of secretory Immunoglobulin A (sIgA), sIgM and free secretory component (SC) by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) using 10-15% gradient minigels (PhastSystem), followed by immunoblotting using various immunological probes. Tear samples were treated in denaturing (SDS) sample buffer under non-reducing as well as reducing conditions, prior to analysis. All normal tear samples contained sIgA as well as free SC (estimated MW: 82kD) but only traces of IgM. Tears from the three serum IgA deficient subjects lacked sIgA but did contain free SC. In two of them sIgM was clearly detected and after treatment of tears with reducing agent, IgM (mu) heavy chain fragments (estimated MW: 78kD) were identified and could be distinguished from other tear proteins after SDS-PAGE. These findings indicate lacrimal secretion of free secretory component, even in the absence of its ligand. On the ocular surface, sIgM may play a compensatory role in IgA deficiency.

The role of bacterial adherence in otitis media with effusion

Adherence of nontypable Haemophilus influenzae and Streptococcus pneumoniae to nasopharyngeal epithelial cells was investigated in vitro. Both strains had higher affinity to the epithelial cells of children than to those of adults. In children, the adherence was significantly greater in patients with otitis media with effusion than in normal subjects. Secretory IgA in nasopharyngeal secretions was found to have antibody activity against the bacteria. Adherence of both bacteria was significantly smaller in the group having secretory IgA antibody activity than in the group having no activity. These results suggest that bacterial adherence to the nasopharynx may play an important role in the pathogenesis of otitis media with effusion in children, and that secretory IgA in nasopharyngeal secretions may be related to the decrease of adherence.

Rapid recovery in mice after combined nasal/oral immunization with killed respiratory syncytial virus

Based on the concept of a common mucosal immune system, the murine gastrointestinal tract was inoculated (oral) with three doses (5, 20, and 40 micrograms) of UV-inactivated respiratory syncytial virus (RSV) in order to elicit a virus-specific immune response in the respiratory tract. Only the 40 micrograms dose induced significant (P less than 0.01) anti-RSV-IgG rises in serum and lung wash compared to controls. To improve the immune response, mice were immunized intranasally under light anesthesia with the same 40 micrograms dosage regimen of killed RSV so that each dose passed through the nose and was swallowed. This combined nasal/oral immunization stimulated anti-RSV-IgG in serum, lung wash and nasal wash (P less than 0.001) and anti-RSV-IgA in lung and nasal wash (P less than 0.001) that were comparable to levels after infection with live RSV. Three days after challenge with live RSV, mice given combined nasal/oral immunization showed suppressed nasal virus shedding (P = 0.025). Nasal virus shedding correlated inversely with concentrations of anti-RSV-Ig in nasal secretions but did not correlate with concentrations in serum.