Indicators of humoral immunity in smokers and nonsmokers working underground

A group of 215 underground shale miners (148 smokers and 67 nonsmokers) was examined for levels of immunoglobulins in sera (IgG, IgA, IgM) and saliva (sIgA), transferrin (TRF), alpha 2-macroglobulin (A 2M) and lysozyme levels in sera (LYS) and saliva (sLYS). The control group consisting of 95 healthy men was selected to match the age of the exposed miners. The mine environment was characterized by the presence of ionizing radiation, due to a geological configuration of the rock. The study revealed that the decline of IgG, IgA and sLYS levels in smokers was significantly deeper than in nonsmokers and controls. The levels of sIgA and serum LYS levels were increased both in smokers and nonsmokers. The change in the serum LYS and A 2M levels in miners did not depend on the smoking habits, except of A 2M levels in miners employed for more than 21 years. The differences were, as a rule, less pronounced in younger miners and tended to increase with the increasing length of work underground. The distribution analysis revealed some inter-miner differences in the susceptibility to these changes and the formation of smaller subgroups of miners with more or less subnormal test values, which supports the hypothesis on the heterogeneity of this population group. The tests showed that the statistical analysis of abnormal test values might play an important role in the assessment of the health risk in individuals. A simultaneous detection of subnormal values in some of pairs of tests may provide decisive data allowing a reliable differentiation between the afflicted miners and the healthy control subjects.     

Immunoglobulins and some serum proteins in children with altered resistance coming from areas with variously polluted atmosphere

In four areas with different types of atmospheric pollution 534 children of school age were examined for serum immunoglobulins (IgG, IgA, IgM and IgE), saliva IgA (sIgA), lysozymes (LYS) and acute phase reactants (alfa-l-antitrypsin - A1AT, alfa-2-macroglobulin -A2M, ceruloplasmin -CPL, transferrin - TRF). The children were divided into two groups: those with altered resistance (AR) comprising allergoses of all types and recurrent or persistent infections and those without the above health problems, i.e. healthy (H). There were more children with AR in areas with higher atmospheric pollution than in control areas. The frequency of AR was higher among boys than among girls. In the control area BN, a number of parameters in the AR group differed significantly from those in the H group. In areas with substantial atmospheric pollution these differences were generally less pronounced. Significant differences were found between the control and polluted areas in many indicators. In the area KO characterized by an intermediate degree of industrial pollution the means of the tested parameters were habitually elevated, whereas in the heavily polluted areas they were decreased. The most sensitive tests for evaluating differences between the areas were the levels of A1AT, LYS, and IgE, while the variations of sIgA, sLYS and CPL were less pronounced.     

Seasonal changes in the relationship of blood calcium levels to immunoglobulins and some of the blood proteins in schoolchildren

Blood and saliva were collected in the autumn and spring from a group of schoolchildren (39 girls, 35 boys) with a mean age of 11.4 years. Serum immunoglobulin IgG, IgA, IgM and IgE, alpha 1-antitrypsin (A 1-AT), alpha 2 macroglobulin (A 2M), transferrin (TRF), ceruloplasmin (CPL), lysozyme (LYS) and pertussis (PE) antibody levels were determined. Calcium (Ca2+) and total serum protein levels were also determined. Secretory IgA (sIgA) and secretory lysozyme (sLYS) levels were assessed in the saliva. A highly significant drop in Ca2+ levels was found in the spring in boys, while in girls there was only a greater scatter of the values. Mean IgG, IgA and IgM values fell significantly in the spring in both sexes, but IgE levels fell significantly only in boys. PE levels rose significantly in the spring in girls. Among the other proteins, all the values rose in boys, except for TRF, whose levels fell. In girls, LYS and TRF levels rose, but all the other values fell. The coefficients of correlation between Ca2+ and the tested proteins showed a significant relationship only for A 2M and PE in girls and only for the total protein level in boys; in boys, the determination coefficient for sIgA and IgM was over 10%. The results do not testify to the existence of a close relationship between blood Ca2+ levels and Ig and other blood protein levels.     

Immunological profiles in workers of a power plant burning coal rich in arsenic content

A group of 47 male adults working in a thermal power plant burning coal containing 900 to 1,500 g of arsenic per ton dry weight was examined on the blood serum immunoglobulins IgG, IgA and IgM content and levels of acute reactants alpha-1-antitrypsin (A1AT), alpha-2-macroglobulin (A2M), transferrin (TRF), orosomucoid (ORO) ceruloplasmin (CPL), and lysozyme (LYS). Investigations in the control group comprising 27 workers from another power plant in the same district where the coal content of arsenic was more than 10 times lower were analogous. The inter-group differences in means were evaluated by t-test, differences in the association of values by F-test, and the correlations with age and the length of exposure were assessed using the regression analysis method. The differences in mean IgG, IgA, IgM, LYS and A2M levels between the exposed and control groups of workers were insignificant or of borderline significance only. In contrast, differences in TRF, ORO and particularly CPL levels were statistically highly significant, in all instances P less than 0.001. In the control group, persons with abnormal values in at least two immunobiochemical tests used accounted for 3.7%, in the group of the exposed for 51% (P less than 0.002). All these findings, especially the rise in CPL concentration levels in the exposed group are discussed on the background of the rise in cancer mortality rates found previously in this group of power plant workers.     

Relationship between canine mucosal and serum immunoglobulin A (IgA) concentrations: serum IgA does not assess duodenal secretory IgA

A double-sandwich enzyme immunoassay method was developed for determination of serum immunoglobulin A (S-IgA) and mucosal secretory immunoglobulin A (sIgA) in duodenal brush samples obtained via endoscopy and the relationship between enteric mucosal sIgA, salivary sIgA and S-IgA in dogs was examined. Twenty healthy dogs underwent routine endoscopy. A brush sample from the duodenal mucosa was obtained and washed in PBS, with a serum sample being taken concurrently. A saliva sample was collected from twelve of these dogs. S-IgA and sIgA with total protein concentrations in the duodenal washings and saliva samples were determined. A significant negative correlation (r = -0.64, P = 0.0059) was found between duodenal sIgA/protein ratios and S-IgA concentrations. Saliva sIgA/protein ratios did not correlate with sIgA/protein ratios of duodenal samples. The method described here allows for direct assessment of duodenal IgA; therefore indirect measures based on serum IgA or salivary IgA can be avoided. In addition, these indirect measures appear to be poor indicators of duodenal sIgA competence in dogs.     

Lack of correlation between serum and salivary concentration levels of immunoglobulin A and lysozyme (muramidase)

The study was conducted in a group of 232 individuals comprising 114 males and 118 females 20 to 67 years old. As revealed by the linear regression analysis method, mean serum concentration levels of immunoglobulin A (IgA) and lysozyme (LYS) were unrelated to values found in the spontaneously secreted saliva specimens. Levels of serum IgA were clearly age-dependent, but no such correlation was recorded in the case of secretory IgA. These findings suggest that tests for salivary IgA can hardly be taken as an equivalent to IgA determinations in the human serum.     

Immunobiochemical profiles of workers differing in the degree of occupational exposure to vinyl chloride

The immunobiochemical studies were conducted in a group of 98 production workers engaged in polyvinyl chloride manufacture from ethylene (group A workers) and in a group of 59 vinyl chloride workers from a chemical plant employing classic production technology from acetylene (group B workers). Both groups of workers were matched by age (group A workers: 37.7 +/- 8.66 years; group B workers: 34.9 +/- 11.2 years) and average exposure length (group A workers: 8.6 +/- 3.0 years; group B workers: 10.7 +/- 8.4 years). All workers were examined for the serum concentrations of immunoglobulins IgG, IgA and IgM and acute reactants lysozyme (LYS), transferrin (TRF), ceruloplasmin (CPL), alpha-l-antitrypsin (AlAT), alpha-2-macroglobulin (A2M) and orosomucoid (ORO). The statistical analysis included calculations of means, standard deviations and 95% confidence intervals. Differences in means were evaluated by t-test, differences in the distribution pattern of values by F-test. Abnormality of values was assessed by comparisons to normal values valid in Czechoslovakia. Group A worked in conditions meeting the MAC 10 mg VC.m-3 comparing with group B workers had elevated levels of IgG (P less than 0.005), IgA and IgM (P less than 0.001 both). Group B workers differed from group A workers by exhibiting significantly elevated levels of AlAT, and CPL. (P less than 0.001). The differences in the frequency of abnormal values between group A and group B worked in substantially less favourable hygienic conditions were significant for immunoglobulins elevated in group A and for ORO (P less than 0.01) and CPL (P less than 0.001) elevated in group B. The possible relationship of these immunobiochemical findings with the degree of vinyl chloride exposure are critically analyzed.     

The class-specific immunoglobulin composition of fluids obtained from various levels of the canine respiratory tract.

Sensitive and specific radioimmunoassays capable of accurately measuring the three major classes of canine immunoglobulins in the 50 to 200 ng/ml range were developed. The concentrations of IgG, IgA, and IgM in samples of fluid obtained from various levels of the canine respiratory tract (stimulated saliva, tracheal washes, and bronchopulmonary lavage supernatants) and in serum were determined by using the radioimmunoassays. The composition of the immunoglobulin classes, expressed as per cent of the total immunoglobulin content of each sample, differed markedly among the respiratory tract-derived fluids and between respiratory fluids and serum. Pilocarpine-stimulated saliva contained predominantly IgA while bronchial washes contained predominantly IgG. The contents of IgA and IgG in tracheal washes were intermediate between those of stimulated saliva and bronchial washes. There appeared to be a progressive decrease in the content of IgA (83% to 19%) and a progressive increase in the content of the IgG (6.3% to 75%) as sampling proceeded from the upper to the lower respiratory tract. The mean IgG/IgA ratios were as follows: stimulated saliva, 0.1; tracheal washes, 2.1; bronchial washes, 4.1; and serum, 23.2. All respiratory tract-derived fluids contained small amounts of IgM. Local and systemic immunization with sheep erythrocytes failed to alter the per cent composition of immunoglobulins in bronchial washes during the primary immune response. The results demonstrate major differences in the composition of immunoglobulins derived from the upper as opposed to the lower respiratory tract. The findings suggest that functional differences may exist in the immunologic apparatus associated with various levels of the respiratory tract.     

Levels of secretory immunoglobulin A, lysozyme (muramidase) and albumin in healthy adults of different ages

The content of secretory IgA (sIgA,) lysozyme and albumin was studied in the saliva of 40 health-service employees of different ages without evident signs of disease. The levels of lysozyme decrease significantly with the advancing age whereas those of sIgA and albumin do not decrease up to the age of 55. The levels of lysozyme and sIgA show a significant mutual correlation.     

合生元益生菌冲剂对提高儿童消化道黏膜免疫的作用

目的探讨健康儿童口服法国合生元益生菌冲剂后的唾液中sIgA(分泌型IgA)含量的变化,从而判定其对提高消化道黏膜免疫的作用。方法选择正常健康儿童28例,根据年龄分为4组,其中从每组随机抽出1或者2例作为对照组,对照组共为7例,而试验组则为21例。收集口服合生元益生菌冲剂前后正常健康儿童唾液标本经放射免疫分析法检测sIgA的含量。结果对照组儿童之间唾液sIgA分泌量差异较大,个体的唾液sIgA水平会随着身体健康状况和饮食条件等呈不稳定情况,而试验组儿童的唾液sIgA分泌量在连续口服益生菌冲剂6天后有了一个新的提高,并在继续服用益生菌冲剂的7天内获得比较高而稳定的水平。结论口服法国合生元益生菌冲剂可有效诱导消化道黏膜免疫应答,提高并维持儿童的免疫力。     

Repeated Oronasal Exposure to Lipopolysaccharide Induced Mucosal IgA Responses in Periparturient Dairy Cows

This study investigated the effects of repeated oronasal treatment with lipopolysaccharide (LPS) on the humoral immune responses in saliva, vaginal mucus, and the plasma markers of the acute phase response in periparturient dairy cows. One hundred pregnant Holstein cows were administered either 3 increasing doses of LPS (n = 50) as follows: 1) 0.01 µg/kg body weight (BW) on d −28, 2) 0.05 µg/kg BW on d −25, and −21, and 3) 0.1 µg/kg BW on d −18, and −14, or sterile saline solution (controls; n = 50) oronasally for 3 consecutive wk starting at 28 d before parturition. Intensive sampling was conducted on thirty cows (n = 15/group). Multiple saliva, vaginal mucus and blood samples were collected around parturition and analyzed for total immunoglobulin-(Ig)A, plasma serum amyloid A (SAA), lipopolysaccharide-binding protein (LBP), anti-LPS IgA, IgG, IgM, tumour necrosis factor(TNF)-α, and interleukin(IL)-1. Results regarding total secretory IgA (sIgA) antibodies showed greater concentrations in the saliva and an overall tendency for higher total sIgA in the vaginal mucus of the LPS-treated cows. Treatment had no effect on plasma sIgA, IgG, IgM anti-LPS antibodies, haptoglobin, SAA, LBP, TNF-α, and IL-1. Treatments by time interactions were observed for SAA and IL-1 with lowered concentrations of both variables in the plasma of LPS-treated cows after parturition. Overall, repeated oronasal LPS treatment clearly enhanced total sIgA antibodies in the saliva, stimulated their production in vaginal mucus shortly before calving, and lowered plasma IL-1 around parturition, but showed limited effects on markers of the acute phase response in the plasma in dairy cows around parturition.     

Roles of salivary components in Streptococcus mutans colonization in a new animal model using NOD/SCID.e2f1-/- mice

Streptococcus mutans plays an important role in biofilm formation on the tooth surface and is the primary causative agent of dental caries. The binding of S. mutans to the salivary pellicle is of considerable etiologic significance and is important in biofilm development. Recently, we produced NOD/SCID.e2f1(-/-) mice that show hyposalivation, lower salivary antibody, and an extended life span compared to the parent strain: NOD.e2f1(-/-). In this study we used NOD/SCID.e2f1(-/-) 4 or 6 mice to determine the roles of several salivary components in S. mutans colonization in vivo. S. mutans colonization in NOD/SCID.e2f1(-/-) mice was significantly increased when mice were pre-treated with human saliva or commercial salivary components. Interestingly, pre-treatment with secretory IgA (sIgA) at physiological concentrations promoted significant colonization of S. mutans compared with sIgA at higher concentrations, or with human saliva or other components. Our data suggest the principal effects of specific sIgA on S. mutans occur during S. mutans colonization, where the appropriate concentration of specific sIgA may serve as an anti-microbial agent, agglutinin, or an adherence receptor to surface antigens. Further, specific sIgA supported biofilm formation when the mice were supplied 1% sucrose water and a non-sucrose diet. The data suggests that there are multiple effects exerted by sIgA in S. mutans colonization, with synergistic effects evident under the condition of sIgA and limited nutrients on colonization in NOD/SCID.e2f1(-/-) mice. This is a new animal model that can be used to assess prevention methods for dental biofilm-dependent diseases such as dental caries.     

One-year follow-up of anti-Leishmania antibody concentrations in serum and saliva from experimentally infected dogs

The quantification of anti-Leishmania antibodies in serum and saliva by a time-resolved immunofluorometric assay is useful for the diagnosis and treatment monitoring of dogs with clinical leishmaniasis. We compared the kinetics of anti-Leishmania IgG2 and IgA antibodies in serum and saliva from 11 Beagle dogs experimentally infected with Leishmania infantum. Most dogs showed detectable concentrations of anti-Leishmania IgG2 earlier in serum (between 3 and 4 months p.i.) than in saliva (between 4 and 6 months p.i.). Overall, a high correlation between concentrations of anti-Leishmania IgG2 in serum and saliva (r = 0.853; P < 0.0001) was observed. The quantification of anti-Leishmania IgA showed less diagnostic value than IgG2, since detectable amounts of IgA were not observed in the saliva of four dogs and in the serum of one dog. In addition, a very low correlation between anti-Leishmania IgA in serum and saliva (r = 0.289; P < 0.001) was observed. Our results indicate that the antibodies against L. infantum in saliva appear approximately 1 month later than in serum, and suggest that there is a threshold for the passing of immunoglobulins from serum to saliva in dogs. These facts should be taken into consideration for a proper interpretation of saliva assays for quantification of antibodies.     

Extraintestinal pathogenic isolates of Escherichia coli do not possess active IgA1, IgA2, sIgA or IgG proteases.

Infections outside of the intestinal tract due to pathogenic strains of Escherichia coli result in significant morbidity, mortality and increased healthcare costs. The ability of these strains to cause both mucosal and systemic infections, as well as recurrent infections due to the same (homologous) strain suggests the hypothesis that strains of E. coli that cause infection outside of the intestinal tract possess proteases that are capable of cleaving IgA1, IgA2, sIgA or IgG. To test this hypothesis the ability of eight E. coli strains, isolated from sites outside of the urinary tract and 14 homologous and 11 heterologous strains of E. coli that were isolated from women with recurrent UTI, to cleave IgA1, IgA2, sIgA or IgG was evaluated. Our experimental design allowed for detection of cell-associated and secreted immunoglobulin proteases in both log and stationary phase. Surprisingly, none of these 33 human clinical isolates when grown in iron depleted Luria-Bertani medium or human urine were able to degrade the immunoglobulins assessed. Despite previous studies suggesting otherwise, the findings from this study support the concept that strains of E. coli that cause infection outside of the intestinal tract do not possess proteases that cleave the human immunoglobulins IgA1, IgA2, sIgA or IgG.     

Nonclassical mucosal antibodies predominate in genital secretions of HIV-1 infected chimpanzees

To identify mucosal immunity in HIV-infected chimpanzees, IgG, IgA, and IgM from plasma, saliva, rectal swabs, vaginal washes, semen, and urethral washes were tested from four male and three female HIV-1_IIIB infected chimpanzees. The level of HIV infections in the seven chimpanzees were classified as high, intermediate and low depending on the number of HIV-1 infected cells per 10⁷ peripheral blood mononuclear cells (PBMC). One male chimpanzee had a relatively high viral load, two males and two females had moderate viral loads and one male and one female had low levels of infection. All seven animals had plasma antibody. The principal finding was that nonclassical mucosal antibodies of the IgG isotype were the predominant antibody in the saliva, rectal swabs, vaginal washes, semen, and urethral washes of infected animals. All plasma and mucosal samples were negative for IgM antibodies. The results show that HIV-1 specific IgG responses and not sIgA predominate at mucosal surfaces of HIV-1_IIIB infected chimpanzees. A trend was observed in which high viral loads correlated with high plasma IgG, IgA and sIgA titers. An overall correlation between relatively high virus loads and high amounts of mucosal IgG was also found.     

Serum concentrations of secretory IgA in pregnancies delivering at term or preterm.

Secretory component (SC) is a phospholipase A2 inhibitor possibly associated with pregnancy maintenance and in serum is bound either to IgA (sIgA) or IgM (sIgM). To determine if serum secretory component levels a) increase during pregnancy, b) fall as term approaches, c) are low in women who will deliver prematurely, serum sIgA was measured at "booking in" and related to weeks of gestation and length of gestation at subsequent noninduced delivery. Levels of sIgA increased during pregnancy; sIgA increased from a non-pregnant value of 1.6 nM +/- 0.2 (mean +/- SEM) to 2.8 nM +/- 0.3 at the end of the second trimester, then fell significantly between 31-34 weeks. Delivery before 37 weeks was associated with significantly reduced serum sIgA levels, particularly in women who delivered before 32 weeks and in whom sIgA concentrations were similar to those of nonpregnant women.     

Studies on Immunoglobulins and Trypsin Inhibitor in Colostrum and Milk from Sows and in Serum of Their Piglets

The concentrations of IgG, IgM, IgA and the specific sow colostrum trypsin inhibitor (SCTI) were measured by radial immunodiffusion in colostrum and milk samples from sows and in serum samples from their offspring during the suckling period. A clear time dependence was found for all the measured variates in both whey and serum. Statistically significant positive correlations were found between, on the one hand, concentrations of IgG and IgA, but not IgM, in sera from 39 suckling piglets 1 and 3 days old, and, on the other hand, concentrations of the same immunoglobulins and of the trypsin inhibitor in maternal colostrum (n = 7). Multiple regression analyses showed that at day 1 and day 3 the levels of both IgG and IgA in serum samples from the suckling piglets were positively influenced by both the SCTI and the IgG or IgA contents in maternal colostrum.     

Factors of humoral resistance in workers exposed to vinyl chloride with a view to smoking habits

Serum samples were assayed in 110 workers (59 smokers and 51 non-smokers) at PVC manufacturing factory, the results being compared with those obtained in a group of age-matched healthy controls. Non-smokers had significantly higher levels of immunoglobulins (IgG, IgA, IgM), while in smokers there was an increase in IgM only. Lysozyme levels (LYS) were elevated in all exposed subjects, but there was a highly significant decrease in the total protein (TP) content. Alfa-2-macroglobulin (A2M) and orosomucoid (ORO) were also elevated in exposed workers. A significant increase was found in ceruloplasmin (CPL), with smokers having higher levels than non-smokers. No difference was detected between the examined groups in transferrin (TRF) and alfa-1-antitrypsin (A1AT). Exposure duration did not correlate with any of the assayed parameters. The positive correlation of IgA levels and inverse correlation of CPL with age in the control group could not be confirmed in the exposed subjects where a significant inverse correlation between age and AlAT levels, which was found to be positive in exposed non-smokers, proved to be inverse in the subgroup of smokers. The authors discuss possible explanations of the reported findings.     

Subclass distribution of antigen-specific IgA antibodies in normal donors and individuals with homozygous C alpha 1 or C alpha 2 gene deletions

To analyze the subclass restriction of Ag-specific IgA, sera and saliva from healthy blood donors and from IgA class or subclass deficient individuals were studied. The latter included donors with or without C alpha 1 or C alpha 2 gene deletions. Monoclonal human IgA1 and a genetically engineered IgA2 antibody, normal human serum and colostrum IgA were used as standards to estimate serum and saliva levels of Ag-specific antibodies. In normal individuals, there was a strong IgA1 preference of naturally acquired antibodies in serum against both polysaccharide Ag (PPS 6A, PPS 23, pneumococcal C-polysaccharide, and LPS from Escherichia coli) and protein Ag (Staphylococcus aureus alpha-toxin and HSV). Specific IgA2 in serum against the tested Ag were frequently not measurable. In contrast, most of the individuals with homozygous C alpha 1 gene deletions displayed substantial amounts of specific IgA2 against protein as well as polysaccharide Ag. The median levels of specific IgA in serum against protein Ag were approximately one-third as compared to normal individuals and one-fifth, or less, against polysaccharide Ag. Normal serum levels of IgA against the tested Ag, restricted to the IgA1 subclass, were noted in two individuals with IgA2 deficiency, one of whom carried a homozygous C alpha 2 gene deletion. Median values of specific IgA, against the tested Ag S. aureus alpha-toxin, HSV, and pneumococcal C-poly-saccharide, from normal healthy donors were approximately four to eight times higher in serum as compared to saliva. Individuals with homozygous C alpha 1 gene deletions displayed increased levels of the various specific IgA2 antibodies in saliva. In conclusion, the individuals with homozygous C alpha 1 gene deletions displayed decreased median levels of specific IgA antibodies in serum despite normal levels of total IgA. Normal levels of both specific IgA and total IgA in saliva were found.