KDP, a Lactobacilli Product from Kimchi, Enhances Mucosal Immunity by Increasing Secretory IgA in Mice and Exhibits Antimicrobial Activity.

The potential of KDP, a lactic acid bacterial strain of Lactobacillus sakei, to enhance the production of mucosal specific immunoglobulin A (IgA) in mice and thereby enhance gut mucosal immunity was examined. KDP is composed of dead cells isolated from the Korean traditional food kimchi. Female BALB/c mice orally received 0.25 mg KDP once daily for 5 weeks and were co-administrated ovalbumin (OVA) for negative control and cholera toxin for positive control. Mice administered KDP exhibited increased secretory IgA (sIgA) contents in the small intestine, Peyer's patches, serum, colon, and lungs as examined by ELISA. KDP also significantly increased the gene expression of Bcl-6, IL-10, IL-12p40, IL-21, and STAT4. In addition, KDP acted as a potent antioxidant, as indicated by its significant inhibitory effects in the range of 16.5-59.4% for DPPH, nitric oxide, maximum total antioxidant capacity, and maximum reducing power. Finally, KDP exhibited potent antimicrobial activity as evidenced by a significant decrease in the growth of 7 samples of gram-negative and gram-positive bacteria and Candida albicans. KDP's adjuvant effect is shown to be comparable to that of cholera toxin. We conclude that KDP can significantly enhance the intestine's secretory immunity to OVA, as well as act as a potent antioxidant and antimicrobial agent. These results suggest that orally administered KDP should be studied in clinical trials for antigen-specific IgA production.

Changes in anti-citrullinated protein antibody isotype levels in relation to disease activity and response to treatment in early rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic inflammatory disease where serum analysis of anti-citrullinated peptide/protein antibodies (ACPA) is an important diagnostic/prognostic tool. Levels and changes of ACPA in RA patients have been studied previously in relation to disease course and therapy response, but less is known regarding ACPA isotype changes in early RA. Hence, recent-onset RA patients (n = 231) were subjected to a 3-year clinical and radiological follow-up. Serum samples were serially collected and ACPA isotypes were analysed using the second-generation cyclic citrullinated peptide (CCP) as capture antigen. Changes in ACPA isotype levels and status were related to disease course and pharmacotherapy. At inclusion, 74% of the patients tested positive for ACPA IgG; 55% for immunoglobulin (Ig)A, 37% for secretory IgA (SIgA) and 35% for IgM. The proportion of positive patients decreased significantly at follow-up regarding ACPA SIgA, IgM and IgA. During the initial 3 months, reduction of the 28-joint disease activity score (DAS28) correlated with reduced levels of ACPA IgG (Rho = 0·242, P = 0·003), IgA (Rho = 0·260, P = 0·008), IgM (Rho = 0·457, P < 0·001) and SIgA (Rho = 0·402, P < 0·001). Levels of ACPA SIgA (P = 0·008) and IgM (P = 0·021) decreased significantly among patients with good response to treatment, which was not seen regarding ACPA IgA or IgG. Changes in ACPA isotype levels were not associated with radiographic damage. In conclusion, ACPA SIgA and IgM declined rapidly upon anti-rheumatic therapy and correlated with decreased disease activity in recent-onset RA. This may indicate that down-regulation of mucosal immunity to citrullinated proteins/peptides and recruitment of new B cells are key features of therapy responses in early RA.

Effect of fluoride on salivary immunoglobulins and sialic acid.

OBJECTIVE:: The aim of our study was to evaluate the effect of fluoride on salivary immunoglobulin and sialic acid levels in children with dental fluorosis and healthy teeth who live in places with high fluoride concentration in drinking water. METHOD:: Fifty-one (51) healthy children between 6 and 12 years old with no caries were randomly selected from primary schools enrolled in the dental-care program operated by the Department of Pediatric Dentistry. The children were divided into two groups: group I comprised 26 children with dental fluorosis [Thylstrup-Fejerskov Dental Fluorosis Index (TFI) = 4] who lived in Isparta (2.7-2.8 ppm), and group II consisted of 25 children without dental fluorosis who were born in low-fluoride areas and had lived in Isparta for only the previous two years. Stimulated and unstimulated saliva were collected and analyzed for fluoride, salivary immunoglobulins and sialic acid levels. RESULTS:: Sialic acid level was correlated negatively with age. Levels of secretory immunoglobulin A (sIgA) and secretory immunoglobulin G (sIgG) were higher in children with dental fluorosis compared with those in group II, although these differences were not significant. CONCLUSION:: Increased sIgA and sIgG levels may arrest the progression of caries in subjects with dental fluorosis. Given the risks of dental fluorosis, further studies of the effects of different fluoride levels in drinking water on salivary composition of children with mixed dentition are needed to confirm the results of our study and to provide data for comparison.

Effect of fluoride on salivary immunoglobulins and sialic acid

Summary Objective: The aim of our study was to evaluate the effect of fluoride on salivary immunoglobulin and sialic acid levels in children with dental fluorosis and healthy teeth who live in places with high fluoride concentration in drinking water. Method: Fifty-one (51) healthy children between 6 and 12 years old with no caries were randomly selected from primary schools enrolled in the dental-care program operated by the Department of Pediatric Dentistry. The children were divided into two groups: group I comprised 26 children with dental fluorosis [Thylstrup-Fejerskov Dental Fluorosis Index (TFI) = 4] who lived in Isparta (2.7-2.8 ppm), and group II consisted of 25 children without dental fluorosis who were born in low-fluoride areas and had lived in Isparta for only the previous two years. Stimulated and unstimulated saliva were collected and analyzed for fluoride, salivary immunoglobulins and sialic acid levels. Results: Sialic acid level was correlated negatively with age. Levels of secretory immunoglobulin A (sIgA) and secretory immunoglobulin G (sIgG) were higher in children with dental fluorosis compared with those in group II, although these differences were not significant. Conclusion: Increased sIgA and sIgG levels may arrest the progression of caries in subjects with dental fluorosis. Given the risks of dental fluorosis, further studies of the effects of different fluoride levels in drinking water on salivary composition of children with mixed dentition are needed to confirm the results of our study and to provide data for comparison.

Effects of lipopolysaccharide on the histomorphology and expression of toll-like receptor 4 in the chicken trachea and lung.

Endotoxin or lipopolysaccharide (LPS) exposure can cause injury to the respiratory airways and in response, the respiratory epithelia express toll-like receptors (TLRs) in many species. However, its role in the innate immunity in the avian respiratory system is poorly understood. The aim of the present study was to evaluate the effects of LPS on the chicken trachea and lung. After intraperitoneal LPS or saline injection, the trachea and lungs were harvested at 0, 12, 36 and 72 h (n = 6 at each time point) and histopathologically analysed using haematoxylin and eosin and periodic acid-Schiff staining, while TLR4 expression was determined by immunohistochemistry and secretory Immunoglobulin A (SIgA) levels by enzyme-linked immunosorbent assay. After LPS stimulation, we observed a remarkable decrease in the number of goblet cells along with obvious disruption and desquamation of the ciliated epithelium in the trachea, blurring of the boundary between pulmonary lobules, narrowed or indistinguishable lumen of the pulmonary atria and leukostasis in the lungs. Following LPS stimulation, TLR4 protein expression was up-regulated in both the trachea and the lungs and was found on the ciliated columnar cells as well as in the submucosa of the trachea, and in the lungs on parenchymal and immune cells. However, SIgA levels were only up-regulated in the trachea at 12 h following LPS stimulation. Hence, this report provides novel information about the effects of LPS on the microstructure of the lower respiratory tract and it is concluded that its intra-peritoneal administration leads to TLR4-mediated destruction of the tracheal epithelium and pulmonary inflammation along with increased SIgA expression in the tracheal mucosa.

Levels of Salivary Immunoglobulin A (SIgA) in HIV Infected Children.

UNLABELLED: Secretory IgA is the main type of immunoglobulin in saliva and is considered to be the main secretion factor of adaptive immunity in the mouth. OBJECTIVE: To assess the effect of Anti Retroviral Therapy on SIgA levels in saliva of HIV infected children. STUDY DESIGN: A cross-sectional sample of 50 HIV infected children aged 6-8 years were divided into 2 groups ; Group 1: children prior to onset of anti-retroviral therapy and Group 2: children undergoing anti-retroviral therapy. Stimulated whole saliva samples were collected from each child following I hour of breakfast. The samples were placed on ice packs and immediately transferred to a laboratory, processed and total SIgA quantification was estimated using ELISA. Data obtained was statistically analyzed. RESULTS: Among HIV infected children, significantly low SIgA levels of 6.2 mg/dl was seen in children prior to ART. CONCLUSION: Salivary IgA levels were significantly low in HIV infected children, particularly in children prior to ART.

Transcutaneous immunization with phosphorylcholine induces antigen-specific mucosal and systemic immune responses in BALB/c mice.

OBJECTIVE: Transcutaneous immunization (TCI) is a novel route of vaccination through application of a topical vaccine antigen on the skin. Phosphorylcholine (PC) is a structural component of a variety of pathogens and anti-PC immune responses protect mice against invasive bacterial diseases. The purpose of the study was to examine the effect of TCI using PC in BALB/c mice. METHODS: TCI was performed in BALB/c mice using PC-keyhole limpet hemocyanin (KLH) plus cholera toxin (CT). Immunogenicity was evaluated by measuring PC-specific IgG and specific IgG1, IgG2a, IgM, IgA, and secretory IgA antibodies by ELISA. The concentrations of IL-4, IL-5, IL-10, IL-12, IL-13 and IFN-γ were also measured using ELISA for mouse. RESULTS: Six months after immunization, IgG after TCI using PC plus CT was significantly higher than in controls, but this was not found for IgA. In saliva, secretory IgA antibodies decreased with a peak level at 2-3 months. IgG1 was significantly higher than IgG2 after TCI. Production of IL-4 from CD4(+) cells was significantly higher after TCI than in controls, whereas production of IFN-γ, IL-5, IL-12 and IL-13 was not detected in either group. CONCLUSION: These results suggest that TCI using PC plus CT with BALB/c mice is a simple approach for induction of systemic and mucosal immune responses that are shifted in the Th-2 direction.

CO(2) pneumoperitoneum increases secretory IgA levels in the gut compared with laparotomy in an experimental animal model.

BACKGROUND: Secretory immunoglobulin A (s-IgA) plays an important role in both gut and systemic immunity. This study aimed to investigate the production of s-IgA resulting from a CO2 pneumoperitoneum compared with a laparotomy. METHODS: Using enzyme-linked immunosorbent assays, s-IgA in stool, malondialdehyde (MDA), and Toll-like receptor 4 (TLR4) in the ileal tissue were evaluated as markers for gut and systemic immune responses in an animal model. The rats were randomly divided into (i) anesthesia-only as the control group; (ii) laparotomy-only as the open group; and (iii) CO2 pneumoperitoneum-only as the pneumoperitoneum group. To evaluate the gut immune system in a time-dependent manner, each group was further divided into short- and long-time subgroups. RESULTS: s-IgA levels did not increase in the open group but significantly increased in the pneumoperitoneum group compared with the control group (p < 0.05). In addition, s-IgA levels in the long-time subgroup significantly increased compared with the short-time subgroup of the pneumoperitoneum group (p < 0.05). TLR4 levels steeply and gradually increased in the open and pneumoperitoneum groups, respectively. MDA levels in the pneumoperitoneum group increased during the early phase and were significantly higher than those in the open group at 24 h (p < 0.05). CONCLUSIONS: This study demonstrated that s-IgA levels in stool increased in the pneumoperitoneum group compared with the open group, suggesting that CO2 pneumoperitoneum may cause transitory damage to the intestinal mucosa.

Evaluation of Royal Sun Agaricus, Agaricus brasiliensis S. Wasser et al., aqueous extract in mice challenged with Salmonella enterica serovar Typhimurium.

This study investigated the effects of Agaricus brasiliensis S. Wasser et al. (=Agaricus blazei Murrill sensu Heinem.) aqueous extract on small intestinal sIgA levels, serum TNF-alpha, IFN-gamma and IL-10 levels, splenic index, bacterial translocation, and histology of small intestine, spleen, and liver from mice orally challenged with 10(6) CFU of Salmonella enterica serovar Typhimurium (SEST). Splenic index values as well as sIgA, TNF-alpha, IFN-gamma, and IL-10 levels were not affected by either A. brasiliensis aqueous extract treatment or by pathogenic challenge. Typical colonies of SEST were recovered from liver, spleen, and mesenteric lymph nodes of challenged animals, but there was no significant difference in this translocation between groups treated or not with A. brasiliensis aqueous extract. Translocation was confirmed by histopathological analysis in mice challenged with SEST, which showed small and diffuse foci of mixed inflammatory infiltrate in hepatic parenchyma. In conclusion, A. brasiliensis aqueous extract as tested in the present study did not influence any of the variables selected to evaluate in vivo its immunomodulatory effect suggested in the literature.

Effect of yoghurt containing Bifidobacterium lactis Bb12® on faecal excretion of secretory immunoglobulin A and human beta-defensin 2 in healthy adult volunteers.

BACKGROUND: Probiotics are used to provide health benefits. The present study tested the effect of a probiotic yoghurt on faecal output of beta-defensin and immunoglobulin A in a group of young healthy women eating a defined diet. FINDINGS: 26 women aged 18-21 (median 19) years residing in a hostel were given 200 ml normal yoghurt every day for a week, followed by probiotic yoghurt containing Bifidobacterium lactis Bb12® (109 in 200 ml) for three weeks, followed again by normal yoghurt for four weeks. Stool samples were collected at 0, 4 and 8 weeks and assayed for immunoglobulin A and human beta-defensin-2 by ELISA. All participants tolerated both normal and probiotic yoghurt well. Human beta-defensin-2 levels in faeces were not altered during the course of the study. On the other hand, compared to the basal sample, faecal IgA increased during probiotic feeding (P = 0.0184) and returned to normal after cessation of probiotic yoghurt intake. CONCLUSIONS: Bifidobacterium lactis Bb12® increased secretory IgA output in faeces. This property may explain the ability of probiotics to prevent gastrointestinal and lower respiratory tract infections.

Influences of long-term antibiotic administration on Peyer's patch lymphocytes and mucosal immunoglobulin A levels in a mouse model.

BACKGROUND: Long-term antibiotic administration is sometimes necessary to control bacterial infections during the perioperative period. However, antibiotic administration may alter gut bacterial flora, possibly impairing gut mucosal immunity. We hypothesized that 1 week of subcutaneous (SC) antibiotic injections would affect Peyer's patch (PP) lymphocyte numbers and phenotypes, as well as mucosal immunoglobulin A (IgA) levels. METHODS: Sixty-one male Institute of Cancer Research mice were randomized to CMZ (cefmetazole 100 mg/kg, administered SC twice a day), IPM (imipenem/cilastatin 50 mg/kg x 2), and control (saline 0.1 mL x 2) groups. After 7 days of treatment, the mice were killed and their small intestines removed. Bacterial numbers in the small intestine were determined using sheep blood agar plates under aerobic conditions (n = 21). PP lymphocytes were isolated to determine cell numbers and phenotypes (CD4, CD8, alphabetaTCR, gammadeltaTCR, B220; n = 40). IgA levels in the small intestinal and bronchoalveolar washings were also measured with ELISA. RESULTS: Antibiotic administration decreased both bacterial number and the PP cell yield compared with the control group. There were no significant differences in either phenotype percentages or IgA levels at any mucosal sites among the 3 groups. CONCLUSIONS: Long-term antibiotic treatment reduces PP cell numbers while decreasing bacterial numbers in the small intestine. It may be important to recognize changes in gut mucosal immunity during long-term antibiotic administration.

[Mucosal immunity in children with HIV infection and the possibility of correcting this immunity].

The influence of bacterial lysate [see text]PC-19 on the mucosal immunity of children with HIV infection was evaluated. The action of this topical immunomodulator was found to increase the synthesis of sIgA, which was indirectly reflected in a rise of the local immunity of the upper respiratory ways, preventing the aggravation of the chronic focal infection and the main disease. It should be pointed out that in a group of HIV-infected children and adolescents with an initially high level of salivary IgG the prescription of preparation [see text]PC-19 led to its considerable decrease. A decrease in the level of IgG and a rise in the content of sIgA in saliva under the action of the preparation correlated with a decrease in inflammatory changes in the nasopharyngeal mucosa. On the basis of results obtained in this study additions to the algorithm of the prophylactic medical observation of children and adolescents with HIV infection have been developed.

The effect of bovine colostrum supplementation on salivary IgA in distance runners.

Secretory IgA in saliva (s-IgA) is a potential mucosal immune correlate of upper respiratory tract infection (URTI) status. Nutritional supplements may improve mucosal immunity, and could be beneficial to athletes who are at increased risk of URTI. In this study, 35 distance runners (15 female, 20 male, age 35 to 58 y) consumed a supplement of either bovine colostrum or placebo for 12 wk. Saliva samples were taken prior to training at baseline, monthly during supplementation, and 2 wk post supplementation. Median levels of s-IgA increased by 79% in the colostrum group after 12 wk intervention, and the time-dependent change from baseline value was significant (P = 0.0291). This significance was still apparent after adjusting for training volume and self-reporting of upper respiratory symptoms. This study has demonstrated increased s-IgA levels among a cohort of athletes following colostrum supplementation. While this result is statistically significant, its physiological interpretation must be viewed with caution due to the small numbers in this study and the large variability in s-IgA levels.

Acute reduction in secretory immunoglobulin A following smoking cessation.

Smokers report an increase in upper respiratory infections in the early phase of stopping smoking. One possible cause is a depletion in secretory immunoglobulin A (S-IgA) which has been observed in one study. The present study sought to establish this finding in smokers using nicotine patches. Ninety-two smokers, trying to stop smoking, were assessed whilst smoking and for up to six weeks of abstinence. All smokers were prescribed 15 mg 16-h nicotine patches. Among abstinent smokers, changes in S-IgA and saliva volume were assessed. During the preliminary analyses, we observed that for the pre-smoking cessation measure a longer time since the last cigarette was significantly related to lower S-IgA levels (P = 0.006). Consequently, the main analysis, of changes in S-IgA from pre-cessation to post-cessation, was confined to those who had smoked within 0.5-1.5 h of the pre-cessation measure (n = 51). There was a significant decline in S-IgA, relative to pre-smoking abstinence levels, following abstinence of one day (P = 0.027), but levels returned to pre-abstinence values after one week. There was no evidence of any significant changes in saliva volume following smoking cessation, relative to pre-cessation levels. Users of 15 mg patches are likely to experience a decline in S-IgA levels on the first day of smoking cessation, independent of saliva volumes, and this decline in S-IgA is likely to occur acutely, within the first few hours of smoking abstinence. This acute drop in S-IgA appears to stem from a factor other than depletion of nicotine from the body. The observed decrease in S-IgA may help to explain the increased susceptibility of smokers to upper respiratory tract infections in the immediate post-cessation period.

Effect of glutamine supplementation on diarrhea, interleukin-8 and secretory immunoglobulin A in children with acute diarrhea.

OBJECTIVE: Glutamine is an important fuel for rapidly dividing cells such as enterocytes and lymphocytes. Exogenous glutamine supplementation in catabolic states preserves intestinal mucosal structure and function, decreases bacterial translocation, and supports normal immunologic responses. This study was planned to assess the effect of glutamine supplementation on duration and severity of diarrhea and to assess its immunomodulatory effect by measuring serum interleukin-8 (IL-8) and salivary immunoglobulin A (sIgA) in children with acute diarrhea. METHODS: In this placebo-controlled, double-blind and randomized trial, 6- to 24-month-old otherwise healthy children admitted to the Diarrheal Diseases Training and Treatment Center with acute diarrhea received either 0.3 g/kg/day of glutamine (n = 63) or placebo (n = 65) for 7 days. Serum IL-8 and sIgA levels were determined on admission and 7 days later. All cases were followed until the diarrheal episode ended. Anthropometric measurements and history of subsequent infectious diseases were monitored monthly for 3 months after treatment. RESULTS: Mean duration of diarrhea in the glutamine treated group was significantly shorter than that of the placebo group (3.40 +/- 1.96 days, 4.57 +/- 2.48 days, respectively; P = 0.004). No differences in serum IL-8 and sIgA were found between groups on admission or 1 week later. During 3 month follow-up, mean weight gain and incidence of infectious diseases were similar in both groups. CONCLUSION: Duration of diarrhea was shorter in children supplemented with glutamine. The beneficial impact of glutamine supplementation seems to be through effects on gastrointestinal mucosa rather than the host immune response.

Immunomodulating effects of peptidic fractions issued from milk fermented with Lactobacillus helveticus.

The effect of peptides released during the fermentation of milk on the humoral immune system and on fibrosarcoma growth was studied. Lactobacillus helveticus was able to release peptidic compounds during milk fermentation due to its high proteolytic activity, as was shown by the degree of proteolysis and size-exclusion HPLC elution profiles. Three fractions of these compounds were separated and fed to mice during different periods (2, 5, and 7 d). The humoral immune response was assessed by following the number of IgA-secreting cells, and the antitumor activity was monitored by studying the regression of subcutaneously implanted fibrosarcomas. Feeding during 2 and 7 d with the medium-sized fraction (Fraction II) significantly increased the IgA-producing cells in the intestines, whereas feeding with the large compound fraction (Fraction I) during 5 d and the small compound fraction (Fraction III) during all three feeding periods provided similar increases. A double dose of Fraction II showed the highest IgA-producing cell count. The increase by Fraction III was shown to be caused by the presence of L-Tryptophan. Fraction II significantly decreased the size of fibrosarcoma when previously fed during 7 d, and feeding with Fraction I during 5 d decreased significantly its size after 35 d of growth. Although the mechanisms by which lactic acid bacteria enhance the immune system are not clear, this study clearly shows that bioactive compounds released in fermented milks contribute to the immunoenhancing and antitumor properties of these products. The release of bioactive peptides by lactic acid bacteria can have important implications on the modulation of the cellular immune response.

Normal Breast Milk Limits the Development of Colitis in IL-10-Deficient Mice.

BACKGROUND AND AIMS: This study examined the role of breast milk in neonatal bacterial colonization of the colon and disease progression in IL-10-deficient mice. METHODS: IL-10-deficient mice were cross-fostered at birth and raised until weaning with a normal mother. Results were compared with normal pups cross-fostered to an IL-10-deficient mother. Mice were examined at various ages for histologic disease, levels of colonic bacteria, and proinflammatory cytokine secretion. RESULTS: IL-10-deficient mice that had been cross-fostered to a normal mother demonstrated normal levels of colonic adherent bacteria and reduced TNFalpha and IFN gamma secretion at 2 to 12 weeks of age. Histologic disease was significantly reduced up to 12 weeks of age. Normal mice cross-fostered to an IL-10-deficient mother had increased levels of adherent bacteria at 2 and 4 weeks and increased IFN gamma secretion. This group also demonstrated slight inflammation up until 12 weeks of age. CONCLUSION: Breast milk has a role in neonatal bacterial colonization. Changing the luminal environment of IL-10-deficient mice during the neonatal period alters the natural disease course.

Actin mediates secretory immunoglobulin A transport: effect of ethanol.

Secretory immunoglobulin A (IgA) is the principle antibody protecting against pathogens at mucosal sites. Ethanol (EtOH) exposure is related to adverse effects on the enterocyte cytoskeleton. The aim of this study was to assess the role of normal cytoskeletal function on IgA transcytosis and its modulation by EtOH by studying Madin-Darby canine kidney (MDCK) cells transfected with the polyimmunoglobulin receptor. MDCK cells were grown as confluent monolayers and treated with 5 per cent EtOH, cytochalasin D (Cyto-D, a cytoskeletal destabilizer), or pretreatment with prostaglandin E2 (a cytoskeletal stabilizer) followed by EtOH. Media alone served as control. IgA was then added to the basolateral side of the chambers, and apical samples were taken for enzyme-linked immunosorbent assay analysis at 0, 3, and 12 hours. Dimeric IgA transcytosis increased in all groups and was significantly depressed by 5 per cent EtOH and Cyto-D. Morphological slides revealed aggregation of actin after Cyto-D treatment. Prostaglandin E2 prevented the decrease in IgA transcytosis seen otherwise with 5 per cent EtOH treatment. We conclude that IgA transcytosis is dependent on actin microfilaments of the cytoskeleton. Decreased IgA transport may lead to mucosal immunodeficiency and infectious complications after EtOH exposure.

Overcoming immune tolerance during oral vaccination against Actinobacillus pleuropneumoniae.

In the preliminary study mice were vaccinated orally with Actinobacillus pleuropneumoniae microsphere oral vaccine. The lung and eye mucous membranes of these mice did not contain increased immunoglobulin A (IgA) following the initial oral vaccination, possibly through antibody persistence and the phenomenon of immune exclusion. A similar tendency was found for serum IgG. However, after the second vaccination, IgA still did not increase significantly, which could be attributed to immune suppression due to the possibility of the intestine inducing immune tolerance. Only the third vaccination overcame this effect and increased the level of IgA. In order to achieve a high systemic and local immune response this study attempted to overcome the initial tolerance to oral vaccination by using temporary immunosuppression, increasing antigen dose, and prolonging vaccine influence. Triamcinolone, used in the later productive phase of the immune response after the first and second vaccinations, but restricted in the inductive phase of the second and third vaccinations, could disable immune tolerance. Suppression of antibody production before the next induction of the immune response by an oral vaccine combined with suppression of cell-suppressor activity led to the creation of systemic immunity with the possibility of high levels of A. pleuropneumoniae growth inhibition. Increased antigen doses or durable consumption of antigen could overcome immune exclusion of antigen by primary antibodies. Even very low doses of vaccine (4.5 mg) could induce a primary immune response, and a dose increased by 10-fold for the second vaccination could overcome tolerance and maintain high systemic immunity. Chronic consumption of oral vaccine led to benefits in the quantity of local (not systemic) antibodies. The outcomes of the study can be adapted for practical oral immunization of pigs.

The effect of pilocarpine on salivary constituents in patients with chronic graft-versus-host disease.

Chronic graft-versus-host disease (cGVHD) is a complex clinical entity with various target organs, including the salivary glands. Oral pilocarpine (Salagen(R)), 30 mg/day, can ameliorate cGVHD-induced xerostomia and improve the flow rate from the major salivary glands. The purpose here was to evaluate the effect of this drug at 30 mg/day on salivary biochemical and immunological composition in cGVHD patients. Significantly higher concentrations of salivary sodium (Na), magnesium (Mg), total protein, albumin, epidermal growth factor (EGF) and total IgG, accompanied by a concomitant increase in total IgA which did not reach significance, were observed in cGVHD patients in comparison with controls, in both resting and stimulated conditions (p < 0.05), while salivary potassium, calcium and phosphate were not altered. Two weeks of oral pilocarpine, at 30 mg/day, resulted in normalization of the altered salivary biochemical and immunological composition in the cGVHD patients. Oral pilocarpine was able to reduce and normalise the elevated Na, Mg, total protein, albumin, EGF, IgG and IgA concentrations in both resting and stimulated conditions. The ability of oral pilocarpine to normalise and reverse the salivary biochemical and immunological alterations induced by cGVHD parallels its known stimulatory effect on salivary flow rates. As the biochemical and immunological composition of saliva provides its protective antimicrobial characteristics, the ability of pilocarpine to abrogate cGVHD salivary gland abnormalities may be of clinical significance.