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PubMed1992

Comparison of the intestinal and serum antibody response in patients with dermatitis herpetiformis.

Dermatitis herpetiformis (DH) is an intensely pruritic, blistering skin disease characterized by cutaneous IgA deposits and an associated, most often asymptomatic, gluten-sensitive enteropathy. When patients with DH are placed on a gluten-free diet both the intestinal abnormality and the cutaneous manifestations of the disease are controlled, suggesting that a mucosal immune response is important in the pathogenesis of DH. Although patients with DH continue to ingest gluten only 40-50% have evidence of an ongoing mucosal immune response in their serum. In order to investigate directly the mucosal immune response in patients with DH the antibody response to dietary antigens was analyzed in intestinal secretions and compared to that found in the serum. Intestinal secretions from six patients with DH and five normal subjects were collected using an intestinal lavage solution and analyzed for total IgA, IgG, IgM, and IgA subclasses, and for IgG, IgA, and IgM antibodies against the dietary antigens bovine beta-lactoglobulin and gliadin. Intestinal secretions from patients with DH contained more IgA than those from normal subjects (mean total IgA: DH = 2.3 mg/ml; normal subjects (NL) = 0.143 mg/ml, P = 0.017). This increase in IgA in intestinal secretions from patients with DH was composed primarily of IgA1 (intestinal IgA: 86% IgA1, 14% IgA2; NL gut secretions: IgA1 = 54%; IgA2 = 46%). Increased IgA antibodies directed against beta-lactoglobulin and gliadin were detected in gut secretions of two of six patients with DH and in none of the normal subjects. Serum IgA antibodies against beta-lactoglobulin and gliadin were detected only in the two subjects who had detectable IgA antibodies in their intestinal secretions. Serum and intestinal IgA anti-beta-lactoglobulin antibodies had similar isoelectric spectrotypes (pI 5.0-6.5), IgA subclass composition, and antigenic reactivity by immunoblot analysis, demonstrating the close relationship between the serum and intestinal IgA antibodies. These data demonstrate that in patients with DH an ongoing mucosal immune response is present in the gut as evidenced by a significantly increased concentration of IgA, predominately IgA1. The strong correlation between detectable serum and intestinal IgA antibodies against dietary antigens demonstrates that the lack of serum IgA antibodies against dietary antigens in some patients with DH is not due to the presence of "blocking" IgA anti-dietary antigen antibodies in intestinal secretions.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed2005

Mucosal response in African catfish after administration of Vibrio anguillarum O2 antigens via different routes.

The aim of this study was to investigate the possibility of mucosal vaccination in African catfish (Clarias gariepinus) with Vibrio anguillarum O2 bacterins. The antigen was administered via different routes: anal intubation, oral administration, intraperitoneal injection and immersion. To monitor the antigen uptake, a competitive ELISA was used. The antibody response was measured using an indirect ELISA. Increased antibody levels were found in bile and mucus upon anal intubation, which was not the case after intraperitoneal injection. The data indicate that oral vaccination of fish may be possible when antigens can reach the second gut segment in sufficient quantities and in the right form as confirmed by the recorded substantial induction of systemic and mucosal immunity. The results obtained are a strong indication for mucosal immune response and the two compartmental models for immune response in fish.

Animals↗
PubMed2002

Route of administration of chimeric BPV1 VLP determines the character of the induced immune responses.

To examine the mucosal immune response to papillomavirus virus-like particles (PV-VLP), mice were immunized with VLP intrarectally (i.r.), intravaginally (i.va.) or intramuscularly (i.m.) without adjuvant. PV-VLP were assembled with chimeric BPV-1 L1 proteins incorporating sequence from HIV-1 gp120, either the V3 loop or a shorter peptide incorporating a known CTL epitope (HIVP18I10). Antibody specific for BPV-1 VLP and P18 peptide was detected in serum following i.m., but not i.r. or i.va. immunization. Denatured VLP induced a much reduced immune response when compared with native VLP. Immune responses following mucosal administration of VLP were generally weaker than following systemic administration. VLP specific IgA was higher in intestine washes following i.r. than i.va. immunization, and higher in vaginal washes following i.m. than i.r. or i.va. immunization. No differences in specific antibody responses were seen between animals immunized with BPV-1 P18 VLP or with BPV-1 V3 VLP. Cytotoxic T lymphocyte precursors specific for the P18 CTL epitope were recovered from the spleen following i.m., i.va. or i.r. immunization with P18 VLP, and were similarly detected in Peyer's patches following i.m. or i.r. immunization. Thus, mucosal or systemic immunization with PV VLP induces mucosal CTL responses and this may be important for vaccines for mucosal infection with human papillomaviruses and for other viruses.

Animals↗
PubMed1991

The adjuvant action of cholera toxin is associated with an increased intestinal permeability for luminal antigens.

This study addresses the question of whether cholera toxin (CT) increases gut permeability for molecules greater than 3000 Da and whether such an effect is associated with an adjuvant function by CT on the gut immune response. We found that CT after oral administration gives rise to strikingly increased gut permeability for Dextran (Mw 3000) concomitantly with a strong enhancing effect on the anti-keyhole limpet hemocyanin (KLH) specific immune response in the lamina propria after oral immunization with KLH plus Dextran and CT. In contrast, the B-subunit of the holotoxin, which lacks the adenylate cyclase/cAMP-activating property of CT, failed to increase gut permeability as well as local anti-KLH immune responses. These results might suggest a causal linkage between the ability of CT to increase gut permeability and its adjuvant property on gut mucosal immune responses. In addition this finding supports the notion that the adenylate cyclase/cAMP system plays a regulatory role in gut permeability and is important in enhancing mucosal immune responses. Based on previous studies and the present data we propose that the mechanism for CT's adjuvant function on mucosal immune responses is by affecting antigen-presenting cells, T and B cells in the gut to give a net enhancing effect on the stimulation of local immunity, and that the CT-induced increase in gut permeability might be part of the adjuvant mechanism by facilitating luminal antigens to access the gut mucosal immune system.

Adenylyl Cyclases↗
PubMed1995

Effect of human immunodeficiency virus on local immunity in children with diarrhoea.

The purpose of this study was to determine the relationship between intestinal mucosal immunity and diarrhoea. Stools were tested for total IgA by radial immunodiffusion, cultured for bacteria and examined for ova/cysts by microscopy. Peripheral blood was screened for HIV-1 antibody by ELISA, CD4 and CD8 enumerated by flow cytometry and phagocytic activity by C. albicans engulfment. A total of 271 children were enrolled with a mean age of 20.3 m (range 0.3-60.0 m). HIV exposed (born to HIV seropositive mothers) had more episodes of diarrhoea than HIV unexposed (born to HIV seronegative mothers) children in the first six months of life (26.0% versus 5.5%, p = 0.002). Exposed children had severe (16/44 versus 6/29, p = 0.02) and prolonged diarrhoea lasting more than nine days (11.0% versus 1.4%, p = 0.03) than unexposed. CD8 counts were significantly higher in exposed than unexposed children (1837.0 versus 1373.0 cells/mm3, p = p.01). Among children aged 15 months and over, HIV seropositive children had severe diarrhoea (4/6 versus 11/32, p<0.01), reduced phagocytic activity (phagocytic index 15.4 versus 28.9, p<0.01), total intestinal IgA (0.2 versus 0.7 mg/ml, p = 0.04) and CD4 counts (624.2 versus 1345.1 cells/mm3, p = 0.01) than seronegative. Reduction of CD4 was more significant in HIV seropositive children with severe diarrhoea (298.7 versus 1318.5 cells/mm3, p = 0.01). Isolation of enteric pathogens was independent of either maternal or child's HIV serostatus although E. coli was more frequent in children with low CD4 counts. These results highlight the importance of mucosal immunity in the intestinal infections. Exposure to HIV, reduced CD4 counts and IgA were associated with diarrhoea probably due to impaired intestinal mucosal immunity.

CD4 Lymphocyte Count↗
PubMed2001

Understanding mucosal responsiveness: lessons from enteric bacterial pathogens.

Mucosal immune responses must discriminate between commensal flora within the lumen and potential pathogens. These responses are highly adapted to induce protection without excessive inflammation. The balances that regulate mucosal immune and inflammatory responses have to be understood if effective mucosal immunity is to be induced through local immunization. This review will summarize some of the lessons learnt from studies of antigens derived from enteric bacterial pathogens and discuss how the gastrointestinal epithelia can 'fight back' when it encounters pathogens.

Animals↗
PubMedDate not supplied

Intestinal mucosal immunosenescence in rats.

The elderly are characterized by systemic immunosenescence and high rates of morbidity and mortality associated with infectious diseases of the intestinal tract. Despite the consensus that the mucosal immune compartment is largely unaffected by aging, there are marked deficits in the intestinal mucosal immune responses of old animals and elderly humans. However, little is known about the mechanism(s) whereby aging disrupts intestinal immunity. Events in the generation of an intestinal immune response may be susceptible to the insults of aging. The first step involves the uptake of antigens by specialized follicular epithelial cells (M cells). There have been no studies on the efficacy of antigen uptake by M cells as a function of age. Little is known about the next step, i.e. antigen presentation by dendritic cells and subsequent isotype switching. The third event is the differentiation of putative immunolobulin A (IgA) plasma cells and their homing from the Peyer's patches (inductive site) to the lamina propria of the small intestine (effector site). Quantitative immunohistochemical and flow cytometry analyses suggest that the homing of IgA immunoblasts may be compromised in old rats and monkeys. Local antibody production/secretion by mature IgA plasma cells in the intestinal wall constitutes the fourth step. In vitro anti-cholera toxin IgA antibody secretion by intestinal lamina propria lymphocytes is equivalent in cells isolated from young adult and senescent rats. The final event in the mucosal immune response is the transport of IgA antibodies across the mucosal epithelial cells and their secretion onto the mucosal surface, i.e. receptor-mediated vesicular translocation of IgA by the intestinal epithelial cells. Binding assays did not detect age-associated declines in either the number or binding affinity of the polymeric immunoglobulin receptor expressed on rodent and monkey intestinal epithelial cells.

Aging↗
PubMed1997

Immune responses in mice after gastric and subcutaneous immunization with BCG.

Mucosal immunization can induce immune responses different from those induced by systemic immunization. In this study, murine immune responses were analysed after immunization through gastric and subcutaneous routes with Mycobacterium bovis BCG. The number of circulating cells secreting antigen-specific immunoglobulins (Ig), and the number of gamma interferon (IFN-gamma) secreting cells in spleen-cell cultures after in vitro stimulation with mycobacterial antigens were analysed at the single cell level by the ELISPOT method. Levels of antigen-specific antibodies in sera were determined by ELISA. In the subcutaneously immunized mice the authors found approximately 100 times more splenic cells secreting antigen-specific IgG than in gastrically immunized mice or control mice. Their levels of antigen-specific IgG in sera were 66-6700 times higher than in sera from gastrically immunized mice or control mice. In contrast, the numbers of IFN-gamma producing cells in spleen-cell cultures after in vitro activation with BCG were equally high in the immunized groups of mice, and for both groups higher than in non-immunized controls. Furthermore, IFN-gamma producing cells could be demonstrated in gastrically immunized animals even without in vitro activation. The results demonstrate that gastric immunization with the BCG vaccine can induce a systemic T cell-mediated immune response against mycobacterial antigens.

Animals↗
PubMed1995

Features of oral immunization.

In this review, we focus on some key areas concerning the unique properties of the mucosal immune system. They are: (1) the fact that the common mucosal immune system consists of different compartments; (2) the advantages of oral vaccination, which can be exploited to antigen-specific sIgA-mediated local immune responses as well as systemic immunity; (3) efficacious oral immunization against respiratory infections; (4) oral tolerance with respect to activation of T cells which, after declining, can be repeatedly reinduced without changes in profile or magnitude, and (5) the use of transgenic plants as a new vaccine source for a new vaccination strategy, i.e. employing edible dietary vaccines.

Administration, Oral↗
PubMed2005

Pulmonary DNA vaccination: concepts, possibilities and perspectives.

Mucosal immunity establishes the first line of defence against pathogens entering the body via mucosal surfaces. Besides eliciting both local and systemic immunity, mucosal vaccination strategies that are non-invasive in nature may increase patient compliance and reduce the need for vaccine application by trained personnel. A relatively new concept is mucosal immunization using DNA vaccines. The advantages of DNA vaccines, such as the opportunity to combine the genetic information of various antigen epitopes and stimulatory cytokines, the enhanced stability and ease of production make this class of vaccines attractive and suitable for mucosal application. In contrast to the area of intranasal vaccination, only a few recent studies have focused on pulmonary immunization and the involvement of the pulmonary immune system in eliciting protective immune responses against inhaled pathogens. This review focuses on DNA vaccine delivery to the lung as a promising approach to prevent pulmonary-associated diseases caused by inhaled pathogens. Attractive immunological features of the lung as a site for immunization, the mechanisms of action of DNA vaccines and the pulmonary application of such vaccines using novel delivery systems will be discussed. We also examine pulmonary diseases prone to prevention or therapeutical intervention by application of DNA vaccines.

Humans↗
PubMed2006

Nasal immunization studies using liposomes loaded with tetanus toxoid and CpG-ODN.

To increase the systemic and mucosal immune responses against the nasally administered tetanus toxoid, liposomes as a drug delivery system and CpG-ODN as an adjuvant were evaluated. Rabbits were nasally immunized with entrapped tetanus toxoid (TT) and CpG-ODN in neutral liposomes and systemic and mucosal immune responses were determined. Liposomes containing TT and CpG-ODN were prepared by dehydration-rehydration method. The volume mean diameter of liposomes was 2.3+/-0.6 microm. Encapsulation efficiency of TT and CpG-ODN was determined as 54.0+/-8.8 and 60.1+/-7.4, respectively. The leakage of the encapsulated TT from liposomes reached 7.38% after 3 months. Encapsulated TT kept its intact structure, and its immunoreactivity was also completely preserved, as shown by SDS-PAGE and ELISA methods. The highest serum IgG and antitoxin titers were observed in groups immunized with solution formulations (P < 0.001). However the highest mucosal sIgA titers were achieved by liposomes encapsulated with TT. CpG-ODN as an adjuvant was able to increase the serum IgG and antitoxin titers when co-administered with TT solution (P < 0.05) or co-encapsulated with TT in liposomes (P < 0.01), but failed to increase the sIgA titers in nasal lavages. No hemolysis occurred on incubation of liposomes and human RBCs. Also after nasal administration of plain liposomes to human volunteers, no local irritation was seen. Intranasal administration of liposomes encapsulated with vaccines showed to be an effective way for inducing the mucosal immune responses.

Administration, Intranasal↗
PubMed2001

Aging impairs intestinal immunity.

The elderly are characterized by immunosenescence accompanied by high rates of morbidity and mortality associated with infectious diseases. Despite suggestions that the mucosal immune compartment is relatively unaffected by aging, there are marked deficits in the intestinal mucosal immune responses of old animals and elderly humans. Little is known about the mechanism(s) whereby aging disrupts intestinal immunity. However, several events in the genesis of the intestinal immune response may be perturbed during aging. The first step is the uptake of antigens by specialized epithelial cells (M cells) that overlie the domes of Peyer's patches. We are unaware of any studies on the efficacy of antigen uptake in the intestine as a function of age. The effects of aging on the next step, antigen presentation by dendritic cells and lymphocyte isotype switching, have not been resolved. The third event is the maturation of immunoglobulin A (IgA) immunoblasts and their migration from the Peyer's patches to the intestinal mucosa. Quantitative immunohistochemical analyses suggest that the migration of these putative plasma cells to the intestinal effector site is compromised in old animals. Local antibody production by mature IgA plasma cells in the intestinal mucosa constitutes the fourth step. We recently reported that in vitro IgA antibody secretion by intestinal lamina propria lymphocytes from young and senescent rats is equivalent. The last event is the transport of IgA antibodies across the epithelial cells via receptor-mediated vesicular translocation onto the mucosal surface of the intestine. Receptor-binding assays did not detect age-associated declines in receptor number or binding affinity in either rodent or primate enterocytes as a function of donor age. Efforts to identify the mechanism(s) responsible for the age-related decline in intestinal mucosal immune responsiveness may benefit by focusing on the homing of IgA immunoblasts to the effector site.

Aging↗
PubMed2005

Chitosan-DNA microparticles as mucosal delivery system: synthesis, characterization and release in vitro.

BACKGROUND: Mucosal immunity is important to defense against dental caries. To enhance mucosal immunity, a DNA vaccine mucosal delivery system was prepared by encapsulating anticaries DNA vaccine (plasmid pGJA-P/VAX) in chitosan under optimal conditions and the characteristics of the microparticles was investigated. Furthermore, the release properties and protective action of microparticles for plasmid were studied in vitro. METHODS: Plasmid loaded chitosan microparticles were prepared by complex coacervation. Three factors, concentration of DNA, sodium sulfate, and the chitosan/DNA ratios in complexes [better expressed as N/P ratio: the number of poly nitrogen (N) per DNA phosphate (P)] influencing preparation were optimized by orthogonal test. The characteristics of microparticles were evaluated by scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). DNA release rate of microparticles in similar gastro fluid (SGF) or similar intestinal fluid (SIF) at 37 degrees C was determined by ultraviolet spectrophotometry. RESULTS: High encapsulation efficiency (96.8%) was obtained with chitosan microparticles made under optimal conditions of 50 mmol/L Na2SO4, 200 microg/ml DNA and N/P ratio of 4. The size of particles was about 4 to 6 microm. The encapsulation process did not destroy the integrity of DNA. When incubated with SIL, after a release of about 10% in the first 60 minutes, no further DNA was released during the following 180 minutes. When incubated with SGL, the microparticles released a small burst (about 11%) in the first 60 minutes, and then slowly released at a constant, but different rate. CONCLUSIONS: These chitosan microparticles showed suitable characteristics in vitro for mucosal vaccination and are therefore a promising carrier system for DNA vaccine mucosal delivery.

Animals↗
PubMed2005

Effectiveness of the B subunit of cholera toxin in potentiating immune responses to the recombinant hemagglutinin/adhesin domain of the gingipain Kgp from Porphyromonas gingivalis.

The hemagglutinin/adhesin HArep domain is present in the gingipains HRgpA and Kgp and in the hemagglutinin HagA of Porphyromonas gingivalis and is felt to be important in the virulence of this bacterium. In the present study, we determined the immunogenicity of recombinant HArep from the gingipain Kgp (termed Kgp-rHArep) and the effectiveness of the B subunit of cholera toxin (CTB), compared to other adjuvants in potentiating a specific response to Kgp-rHArep following intranasal (i.n.) immunization of mice. Furthermore, we determined the effectiveness of anti-Kgp-rHArep antibodies in protection against P. gingivalis invasion of epithelial cells. Evidence is provided that Kgp-rHArep was effective in inducing immune responses following systemic or mucosal immunization. Kgp-rHArep induced both a Th1- and Th2-type response following i.n. immunization. Immunization of mice with Kgp-rHArep and CTB, either admixed or chemically conjugated to the antigen, via the i.n. route, resulted in a significant augmentation of the systemic and mucosal immune response to Kgp-rHArep, which was similar to or higher than the responses seen in mice immunized with antigen and the other adjuvants tested. CTB and the heat-labile toxin of Escherichia coli potentiated a Th1- and Th2-type response to Kgp-rHArep, whereas the adjuvant monophosphoryl lipid A preferentially promoted a Th1-type response to the antigen. Furthermore, anti-Kgp-rHArep antibodies were shown to protect against P. gingivalis invasion of epithelial cells in an in vitro system. These results demonstrate the effectiveness of certain mucosal adjuvants in potentiating and in altering the nature of the immune response to Kgp-rHArep following i.n. immunization, and provide evidence for the potential usefulness of Kgp-rHArep for the development of a vaccine against periodontal disease.

Adhesins, Bacterial↗
PubMed2005

Mucosal vaccination against diphtheria using starch microparticles as adjuvant for cross-reacting material (CRM197) of diphtheria toxin.

Mucosal vaccination has the advantage of eliciting a local mucosal immune response as well as a systemic response. In this investigation, polyacryl starch microparticles were conjugated to diphtheria toxin cross-reacting material (CRM197) as a mucosal adjuvant for oral or intranasal immunisation of mice. Various methods of stabilising CRM197 with formaldehyde were investigated. A good systemic and local mucosal immune response was attained with oral immunisation when CRM197 was treated with a relatively low formaldehyde concentration prior to conjugation to the microparticles. No immune response was seen after intranasal immunisation.

Administration, Oral↗
PubMed2005

Two secretory immune systems (mucosal and barrier) in human intrauterine development, normal and pathological (Review).

The role of protein components of the secretory immune system (SIS), such as the polymeric immunoglobulin receptor/secretory component (pIgR/SC), immunoglobulins (Igs) and joining (J) chain, in human intrauterine development was reviewed. These components are already present in 3.5- to 4-week-old embryos, and found in all tissues and organs of epithelial origin. The SIS is made up of two parts: the SIS of mucous membranes and their derivatives (mucosal or secretory immune system), and the SIS of barrier structures (barrier immune system). During organogenesis, SC disappears from the cells of organs that lose their exocrine Ig-secretion function, such as the hypophysis, pancreatic islands and adrenal glands. In cells and tissues of mesenchymal origin, SC is absent from the start, i.e. during their initial development. As examples of the barrier immune system, blood-tissue and tissue-tissue barriers, such as the chorion of the placenta, the epithelium of the choroid plexuses in the brain, as well as other barrier structures to Ig transfer were considered. Besides the SC and J chain, Fc receptors, cellular and tissue structures participate in this process. Three stages were described in Ig transfer: i) passing from the maternal blood into intervillous spaces and the trophoblast, ii) shifting in the intravillous stroma and its cells, and iii) excretion into embryonic (fetal) blood through the endothelium of the trophoblastic villous capillaries. Igs of maternal origin, mainly IgG and least abundant IgA, pass through the placental barrier in healthy embryos. Following a massive antigenic attack, the increased exocrine secretion of IgG, IgA, and IgM to a lesser extent, are already seen in embryos, reflecting increased functional activity of the SIS. Thus, in human intrauterine development, the SIS is a very early immune defensive system, which presents and acts before the appearance of the common lymphoid system.

Embryo, Mammalian↗
PubMed1997

Cholecystokinin modulates mucosal immunoglobulin A function.

BACKGROUND: We have established that mucosal immunoglobulin A (IgA) production is highly dependent on cholecystokinin release and is markedly suppressed by glucocorticoids. The purpose of the present study was to examine the role of cholecystokinin on the functional responsiveness of the mucosal IgA system in glucocorticoid treated rats. METHODS: A total of 24 Fischer rats were assigned to three groups of 8 animals each. Animals were injected with vehicle (CON), dexamethasone (DEX) (0.08 mg/150 g), or DEX (0.08 mg/150 gm) and ARL1294KF (500 ng twice daily), a novel and potent long-acting cholecystokinin agonist (DEX+CCK). Animals were treated for 48 hours and killed. Duodenum was harvested, and the total mucosal concentration of cholecystokinin was measured by radioimmunoassay. Mucosal IgA was assayed by quantitation of immunoreactive cells in the ileum. Bacterial adherence was evaluated by quantitative culture of vigorously washed stripped cecal mucosa. Transepithelial electrical resistance, a measure of tight junction permeability, was assessed by mounting strips of adjacent cecal mucosa in Ussing chambers. RESULTS: Glucocorticoid administration resulted in a statistically significant (p < 0.001) decrease in duodenal cholecystokinin, decreased IgA, and impaired mucosal immunity (increased bacterial adherence and decreased tissue resistance). Cholecystokinin administration preserved mucosal immune function in DEX-treated rats. CONCLUSIONS: Cholecystokinin may play an important role in maintaining the functional responsiveness of mucosal immunity during catabolic stress.

Animals↗
PubMed2000

Catalase immunization from Pseudomonas aeruginosa enhances bacterial clearance in the rat lung.

Pseudomonas aeruginosa is a common cause of infection in immunocompromised patients and is the major contributor to morbidity in individuals with cystic fibrosis (CF). The antibiotic resistance shown by this pathogen and morbidity in patients with chronic infection has encouraged investigations into the development of a vaccine. This study reports the purification of a 60 kDa protein, isolated from a mucoid strain of P. aeruginosa, identified by amino acid sequence analysis as the catalase protein (KatA). A rat model of acute P. aeruginosa respiratory infection was used to investigate the immunogenicity of KatA and determine the potential of mucosal immunization with KatA to protect against infection. Immunization regimens compared a single intra-Peyer's patch (IPP) immunization with an IPP primary inoculation followed by an intratracheal boost to the lungs. Mucosal immunization with KatA resulted in significant pulmonary clearance of both homologous (p<0.001) and heterologous (p<0.05) strains of P. aeruginosa. Both immunization regimens enhanced bacterial clearance, increased the rate of recruitment of phagocytes to the bronchoalveoli and induced KatA-specific antibody. However, the regimen that included a boost induced a more effective immune response that also resulted in better clearance of P. aeruginosa from the lungs. Mucosal immunization induced KatA- specific antibodies in the serum and the bronchoalveolar lavage, and KatA-specific lymphocyte proliferation in vitro in cells isolated from the mesenteric lymph nodes of immunized rats. The data presented suggests that KatA has the potential to afford a protective immune response against pulmonary infection by P. aeruginosa

Animals↗