RESUMEN
Research on innovative mucosal adjuvants is essential to develop new vaccines for safe mucosal application. In this work, we propose the development of a Lactococcus lactis that expresses a variant of flagellin on its surface (FliC131*), to increase the adjuvanticity of the living cell and cell wall-derived particles (CWDP). We optimized the expression of FliC131*, and confirmed its identity and localization by Western blot and flow cytometry. We also generated CWDP containing FliC131* (CDWP-FliC131*) and evaluated their storage stability. Lastly, we measured the human TLR5 stimulating activity in vitro and assessed the adjuvanticity in vivo using ovalbumin (OVA) as a model antigen. As a result, we generated L. lactis/pCWA-FliC131*, that expresses and displays FliC131* on its surface, obtained the corresponding CWDP-FliC131*, and showed that both activated hTLR5 in vitro in a dose-dependent manner. Furthermore, CWDP-FliC131* retained this biological activity after being lyophilized and stored for a year. Finally, intranasal immunization of mice with OVA plus live L. lactis/pCWA-FliC131* or CWDP-FliC131* induced OVA-specific IgG and IgA in serum, intestinal lavages, and bronchoalveolar lavages. Our work demonstrates the potential of this recombinant L. lactis with an enhanced adjuvant effect, prompting its further evaluation for the design of novel mucosal vaccines.
Asunto(s)
Adyuvantes Inmunológicos , Flagelina , Lactococcus lactis , Ratones Endogámicos BALB C , Ovalbúmina , Receptor Toll-Like 5 , Lactococcus lactis/inmunología , Animales , Flagelina/inmunología , Flagelina/administración & dosificación , Ratones , Humanos , Ovalbúmina/inmunología , Ovalbúmina/administración & dosificación , Receptor Toll-Like 5/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Femenino , Inmunidad Mucosa/efectos de los fármacos , Inmunidad Mucosa/inmunología , Inmunización/métodos , Administración IntranasalRESUMEN
We characterized two LysM domains of Limosilactobacillus fermentum, belonging to proteins Acglu (GenBank: KPH22907.1) and Pgb (GenBank: KPH22047.1) and bacterium like particles (BLP) derived from the immunomodulatory strain Lacticaseibacillus rhamnosus IBL027 (BLPs027) as an antigen display platform. The fluorescence protein Venus fused to the novel LysM domains could bind to the peptidoglycan shell of lactobacilli and resisted harsh conditions such as high NaCl and urea concentrations. Acglu with five LysM domains was a better anchor than Pgb baring only one domain. Six-week-old BALB/c mice were nasally immunized with the complex Venus-Acglu-BLPs027 at days 0, 14 and 28. The levels of specific serum IgG, IgG1 and IgG2a and the levels of total immunoglobulins (IgT) and IgA in broncho-alveolar lavage (BAL) were evaluated ten days after the last boosting. Venus-Acglu-BLPs027, nasally administered, significantly increased specific BAL IgT and IgA, and serum IgG levels. In addition, spleen cells of mice immunized with Venus-Acglu-BLPs027 secreted TNF-α, IFN-γ and IL-4 when stimulated ex vivo in a dose-dependent manner. We constructed a Gateway compatible destination vector to easily fuse the selected LysM domain to proteins of interest for antigen display to develop mucosal subunit vaccines.
Asunto(s)
Inmunidad Mucosa/inmunología , Limosilactobacillus fermentum/inmunología , Limosilactobacillus fermentum/metabolismo , Adyuvantes Inmunológicos , Administración Intranasal , Animales , Femenino , Inmunización/métodos , Inmunoglobulina A/inmunología , Lactobacillus/inmunología , Lactobacillus/metabolismo , Lacticaseibacillus rhamnosus/inmunología , Lacticaseibacillus rhamnosus/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Dominios Proteicos/inmunología , VacunaciónRESUMEN
Different body systems (epidermis, respiratory tract, cornea, oral cavity, and gastrointestinal tract) are in continuous direct contact with innocuous and/or potentially harmful external agents, exhibiting dynamic and highly selective interaction throughout the epithelia, which function as both a physical and chemical protective barrier. Resident immune cells in the epithelia are constantly challenged and must distinguish among antigens that must be either tolerated or those to which a response must be mounted for. When such a decision begins to take place in lymphoid foci and/or mucosa-associated lymphoid tissues, the epithelia network of immune surveillance actively dominates both oral and gastrointestinal compartments, which are thought to operate in the same immune continuum. However, anatomical variations clearly differentiate immune processes in both the mouth and gastrointestinal tract that demonstrate a wide array of independent immune responses. From single vs. multiple epithelia cell layers, widespread cell-to-cell junction types, microbial-associated recognition receptors, dendritic cell function as well as related signaling, the objective of this review is to specifically contrast the current knowledge of oral versus gut immune niches in the context of epithelia/lymphoid foci/MALT local immunity and systemic output. Related differences in 1) anatomy 2) cell-to-cell communication 3) antigen capture/processing/presentation 4) signaling in regulatory vs. proinflammatory responses and 5) systemic output consequences and its relations to disease pathogenesis are discussed.
Asunto(s)
Alostasis , Homeostasis , Inmunidad Mucosa/inmunología , Vigilancia Inmunológica/inmunología , Mucosa Intestinal/inmunología , Mucosa Bucal/inmunología , Inmunidad Adaptativa , Animales , Presentación de Antígeno , Traslocación Bacteriana/inmunología , Moléculas de Adhesión Celular/fisiología , Comunicación Celular , Células Dendríticas/inmunología , Disbiosis/inmunología , Células Epiteliales/inmunología , Humanos , Inflamación , Uniones Intercelulares/fisiología , Mucosa Intestinal/citología , Microbiota , Mucosa Bucal/citología , Moco/fisiología , Especificidad de Órganos , Saliva/inmunología , Transducción de SeñalRESUMEN
BACKGROUND: Overall, there are over 30 different sexually transmitted infections with Neisseria gonorrhoeae being the third most frequent with a reported 78 million cases per year. Gonococcal infection causes genital inflammation, which can be a risk factor for others sexually transmitted infections, particularly human immunodeficiency virus. Gonorrhea is a treatable disease, but recently an increase in antibiotic resistance has been of concern. There are currently no vaccines available. However, parenteral vaccination with anti N. meningitidis serogroup B vaccine has been reported to decrease the incidence of gonococcal burden in New Zealand and in Cuba despite the fact that parenteral vaccination is not deemed to induce mucosal IgA. Here we explore possible mechanisms of protection against gonococcal infection through parenteral meningococcal B vaccination. METHODS: Ninety-two serum, saliva and oropharyngeal swabs samples of young adults (healthy and Neisseria carriers) of the internal higher school were obtained. They have been vaccinated with VA-MENGOC-BC (MBV) during their infancy and boosted with a third dose during this study. Serum and saliva samples were analyzed by ELISA and Western blot to measured IgG and IgA antibodies against N. meningitidis and N. gonorrhoeae antigens. N. meningitidis carriers were determined by standard microbiologic test. In addition, we reviewed epidemiologic data for N. meningitidis and N. gonorrhoeae infections in Cuba. RESULTS: Epidemiologic data show the influence of MBV over gonorrhea incidence suggesting to be dependent of sexual arrival age of vaccines but not over syphilis. Laboratorial data permit the detection of 70 and 22 noncarriers and carriers of N. meningitidis, respectively. Serum anti-MBV antigens (PL) responses were boosted by a third dose and were independent of carriage stages, but saliva anti-PL IgA responses were only present and were significant induced in carriers subjects. Carriers boosted with a third dose of MBV induced similar antigonococcal and -PL saliva IgA and serum IgG responses; meanwhile, serum antigonococcal IgG was significantly lower. In saliva, at least 2 gonococcal antigens were identified by Western blot. Finally, gonococcal-specific mucosal IgA antibody responses, in addition to the serum IgG antibodies, might contributed to the reduction of the incidence of N. gonorrhoeae. We hypothesize that this might have contributed to the observed reductions of the incidence of N. gonorrhoeae. CONCLUSION: These results suggest a mechanism for the influence of a Proteoliposome-based meningococcal BC vaccine on gonococcal incidence.
Asunto(s)
Anticuerpos Antibacterianos/sangre , Gonorrea/prevención & control , Inmunidad Mucosa/inmunología , Vacunas Meningococicas/inmunología , Neisseria gonorrhoeae/inmunología , Neisseria meningitidis/inmunología , Vacunación/métodos , Adolescente , Reacciones Cruzadas , Cuba/epidemiología , Femenino , Gonorrea/epidemiología , Humanos , Incidencia , Inyecciones Intramusculares , Masculino , Vacunas Meningococicas/administración & dosificación , Proteolípidos/administración & dosificación , Proteolípidos/química , Proteolípidos/inmunología , Saliva/inmunología , Serogrupo , Adulto JovenRESUMEN
Brucellosis is one of the most prevalent bacterial zoonosis of worldwide distribution. The disease is caused by Brucella spp., facultative intracellular pathogens. Brucellosis in animals results in abortion of fetuses, while in humans, it frequently manifests flu-like symptoms and a typical undulant fever, being osteoarthritis a common complication of the chronic infection. The two most common ways to acquire the infection in humans are through the ingestion of contaminated dairy products or by inhalation of contaminated aerosols. Brucella spp. enter the body mainly through the gastrointestinal and respiratory mucosa; however, most studies of immune response to Brucella spp. are performed analyzing models of systemic immunity. It is necessary to better understand the mucosal immune response induced by Brucella infection since this is the main entry site for the bacterium. In this review, some virulence factors and the mechanisms needed for pathogen invasion and persistence are discussed. Furthermore, some aspects of local immune responses induced during Brucella infection will be reviewed. With this knowledge, better vaccines can be designed focused on inducing protective mucosal immune response.
Asunto(s)
Brucelosis/inmunología , Inmunidad Mucosa/inmunología , Mucosa Intestinal/inmunología , Mucosa Respiratoria/inmunología , Brucella/patogenicidad , Humanos , Virulencia/inmunologíaRESUMEN
Brucella enters their hosts mostly through mucosae from where it spreads systemically. Adhesion to extracellular matrix (ECM) components or to host cells is important for the infectious process, and is mediated by several adhesins, including the BtaF trimeric autotransporter. Although Th1 responses and gamma interferon (IFN-γ) are important for protection, antibodies able to block adhesions might also contribute to prevent Brucella infection. We evaluated the importance of BtaF for respiratory Brucella infection, and characterized the immune response and protection from mucosal challenge induced by nasal vaccination with recombinant BtaF. While lung CFU numbers did not differ at day 1 p.i. between mice intratracheally inoculated with B. suis M1330 (wild type) and those receiving a ΔbtaF mutant, they were reduced in the latter group at 7 and 30 days p.i. For vaccination studies the BtaF passenger domain was engineered and expressed as a soluble trimeric protein. Mice were immunized by the nasal route with BtaF or saline (control group) plus the mucosal adjuvant c-di-AMP. Specific anti-BtaF antibodies (IgG and IgA) were increased in serum, including a mixed IgG2a/IgG1 response. In vitro, these antibodies reduced bacterial adhesion to A549 alveolar epithelial cells. Specific IgA antibodies were also increased in several mucosae. Spleen cells from BtaF immunized mice significantly increased their IL-2, IL-5, IL-17, and IFN-γ secretion upon antigen stimulation. In cervical draining lymph nodes, antigen-experienced CD4+ T cells were maintained mainly as central memory cells. A BtaF-specific delayed-type hypersensitivity response was detected in BtaF immunized mice. Lung cells from the latter produced high levels of IFN-γ upon antigen stimulation. Although nasal immunization with BtaF did not protect mice against B. suis respiratory challenge, it conferred significant protection from intragastric challenge; the splenic load of B. suis was reduced by 3.28 log CFU in immunized mice. This study shows that nasal vaccination with BtaF+c-di-AMP protects against intragastric challenge with B. suis by inducing local and systemic antibody responses, central memory CD4+ T cells and strong Th1 responses. Therefore, although BtaF vaccination did not protect from B. suis respiratory infection, this adhesin constitutes a promising immunogen against mucosal B. suis infection.
Asunto(s)
Adhesinas Bacterianas/genética , Antígenos Bacterianos/inmunología , Brucella suis/fisiología , Brucelosis/inmunología , Brucelosis/microbiología , Inmunidad Adaptativa , Adhesinas Bacterianas/metabolismo , Administración Intranasal , Animales , Linfocitos T CD4-Positivos , Fosfatos de Dinucleósidos/metabolismo , Femenino , Humanos , Inmunidad Mucosa/inmunología , Inmunización/métodos , Ratones , VirulenciaRESUMEN
Introduction: Lower respiratory tract infections are the fourth cause of death worldwide and pneumococcus is the leading cause of pneumonia. Nonetheless, existing pneumococcal vaccines are less effective against pneumonia than invasive diseases and serotype replacement is a major concern. Protein antigens could induce serotype-independent protection, and mucosal immunization could offer local and systemic immune responses and induce protection against pneumococcal colonization and lung infection. Areas covered: Immunity induced in the experimental human pneumococcal carriage model, approaches to address the physiological barriers to mucosal immunization and improve delivery of the vaccine antigens, different strategies already tested for pneumococcal mucosal vaccination, including live recombinant bacteria, nanoparticles, bacterium-like particles, and nanogels as well as, nasal, pulmonary, sublingual and oral routes of vaccination. Expert opinion: The most promising delivery systems are based on nanoparticles, bacterial-like particles or nanogels, which possess greater immunogenicity than the antigen alone and are considered safer than approaches based on living cells or toxoids. These particles can protect the antigen from degradation, eliminating the refrigeration need during storage and allowing the manufacture of dry powder formulations. They can also increase antigen uptake, control release of antigen and trigger innate immune responses.
Asunto(s)
Inmunidad Mucosa/inmunología , Vacunas Neumococicas/administración & dosificación , Neumonía Neumocócica/prevención & control , Animales , Antígenos Bacterianos/inmunología , Humanos , Nanopartículas , Vacunas Neumococicas/inmunología , Neumonía Neumocócica/inmunología , Serogrupo , Streptococcus pneumoniae/inmunología , Streptococcus pneumoniae/aislamiento & purificación , Vacunación/métodosRESUMEN
OBJECTIVE: The posterior vagus nerve trunk innervates the entire small intestine, and elucidating its modulatory role in the IgA response was the aim of this study. METHODS: Two groups of six male BALB/c mice underwent sham or posterior subdiaphragmatic vagotomy and were euthanized on the 14th postoperative day; then, the small intestines were dissected. The intestinal fluid was harvested for antibody analysis by ELISA, and cell suspensions from Peyer's patches and lamina propria were prepared for cytofluorometric analysis of plasma cells and T lymphocytes. The CD4+ T cells were labeled for the intracellular IgA-producing interleukins (ILs)-4, -5, -6, and -10; transforming growth factor (TGF)-ß; and the inflammatory cytokines tumor necrosis factor (TNF)-α, interferon (IFN)-γ, and IL-12. In the intestinal tissue samples, myeloperoxidase (MPO) visualization and the enzymatic activity were assessed by immunohistochemistry and ELISA, respectively. The data were analyzed by Student's t test, and the differences were considered significant at p < 0.05. RESULTS: In the vagotomy group, the IgA levels and the CD4+ T cells labeled with mediators that promote IgA secretion, including IL-4 (only at lamina propria), TNF-α, and IFN-γ, were decreased, whereas the lamina propria IgA+ plasma cells and MPO presence/activity were increased; changes in the IgM levels, IgM+ plasma cells, and CD4+ T cells labeled with TGF-ß, which have a role in class switch recombination, were not observed. CONCLUSION: The downmodulating impact of vagotomy on IgA levels may result from defective IgA secretion without affecting class switch recombination, whereas vagotomy evoked a proinflammatory response regarding MPO. These findings may reflect the role of the vagus nerve on the control of the IgA response in the small intestine.
Asunto(s)
Inmunidad Mucosa/inmunología , Inmunoglobulina A/inmunología , Mucosa Intestinal/inmunología , Intestino Delgado/inmunología , Nervio Vago/fisiología , Animales , Linfocitos T CD4-Positivos/inmunología , Regulación hacia Abajo , Mucosa Intestinal/inervación , Intestino Delgado/inervación , Masculino , Ratones , Ratones Endogámicos BALB C , Células Plasmáticas/inmunología , VagotomíaRESUMEN
The main challenge for vaccine development or improvement is the lack of safe adjuvants or immunostimulants that induce protective immune responses and can be used for mucosal immunization, which is a highly desirable strategy for vaccination against infectious diseases acquired by oral or intranasal routes. One promising alternative is the use of biodegradable and biocompatible polymeric microparticles. Recently, we developed an immobilization and delivery system with starch microparticles (SMPs) and a starch-binding domain (SBDtag) suitable for the mucosal administration of antigens and the induction of antigen-specific immune responses. Here, we explore the immunostimulant and reinforcing potential of the system using BALB/c mice with progressive pulmonary tuberculosis (PPT). The heat shock protein alpha-crystallin from Mycobacterium tuberculosis immobilized on SMPs (µAcr-SBDtag) or SMPs alone were administered nasally as boosters to BCG-vaccinated mice without any extra adjuvant. The mice were challenged intratracheally with either moderately virulent or highly virulent M. tuberculosis strains. Our results showed that the administration of either the immobilized antigen or SMPs asa booster for the BCG vaccination induced a significant reduction of bacterial loads in the lungs of mice, even more than in mice that received the BCG vaccination alone. Since no difference was observed in pulmonary bacillary burdens between the two reinforced groups, the obtained effect was most likely primarily caused by the starch. As determined by histological study, the administration of boosters did not contribute to the progress of pneumonia, which diminishes the safety concerns related to the administration of SMPs intranasally. Taken together, our findings suggest that this system may be considered asa new carbohydrate-based adjuvant suitable for mucosal vaccines against tuberculosis and other infectious diseases, and more generally, they highlight the potential of particulate α-glucans as immune response modifiers.
Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Vacuna BCG/uso terapéutico , Mycobacterium tuberculosis/inmunología , Mycobacterium tuberculosis/patogenicidad , Almidón/química , Adyuvantes Inmunológicos/administración & dosificación , Administración Intranasal , Animales , Vacuna BCG/química , Vacuna BCG/inmunología , Inmunidad Mucosa/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Mycobacterium bovis/inmunología , Mycobacterium bovis/patogenicidad , Tuberculosis/inmunología , Tuberculosis/prevención & control , Vacunas contra la Tuberculosis/administración & dosificación , Vacunas contra la Tuberculosis/química , Vacunas contra la Tuberculosis/inmunología , Vacunas contra la Tuberculosis/uso terapéuticoRESUMEN
BACKGROUND: Replacement of the trivalent oral poliovirus vaccine (tOPV) with bivalent types 1 and 3 oral poliovirus vaccine (bOPV) and global introduction of inactivated poliovirus vaccine (IPV) are major steps in the polio endgame strategy. In this study, we assessed humoral and intestinal immunity in Latin American infants after three doses of bOPV combined with zero, one, or two doses of IPV. METHODS: This open-label randomised controlled multicentre trial was part of a larger study. 6-week-old full-term infants due for their first polio vaccinations, who were healthy on physical examination, with no obvious medical conditions and no known chronic medical disorders, were enrolled from four investigational sites in Colombia, Dominican Republic, Guatemala, and Panama. The infants were randomly assigned by permuted block randomisation (through the use of a computer-generated list, block size 36) to nine groups, of which five will be discussed in this report. These five groups were randomly assigned 1:1:1:1 to four permutations of schedule: groups 1 and 2 (control groups) received bOPV at 6, 10, and 14 weeks; group 3 (also a control group, which did not count as a permutation) received tOPV at 6, 10, and 14 weeks; group 4 received bOPV plus one dose of IPV at 14 weeks; and group 5 received bOPV plus two doses of IPV at 14 and 36 weeks. Infants in all groups were challenged with monovalent type 2 vaccine (mOPV2) at 18 weeks (groups 1, 3, and 4) or 40 weeks (groups 2 and 5). The primary objective was to assess the superiority of bOPV-IPV schedules over bOPV alone, as assessed by the primary endpoints of humoral immunity (neutralising antibodies-ie, seroconversion) to all three serotypes and intestinal immunity (faecal viral shedding post-challenge) to serotype 2, analysed in the per-protocol population. Serious and medically important adverse events were monitored for up to 6 months after the study vaccination. This study is registered with ClinicalTrials.gov, number NCT01831050, and has been completed. FINDINGS: Between May 20, 2013, and Aug 15, 2013, 940 eligible infants were enrolled and randomly assigned to the five treatment groups (210 to group 1, 210 to group 2, 100 to group 3, 210 to group 4, and 210 to group 5). One infant in group 1 was not vaccinated because their parents withdrew consent after enrolment and randomisation, so 939 infants actually received the vaccinations. Three doses of bOPV or tOPV elicited type 1 and 3 seroconversion rates of at least 97·7%. Type 2 seroconversion occurred in 19 of 198 infants (9·6%, 95% CI 6·2-14·5) in the bOPV-only groups, 86 of 88 (97·7%, 92·1-99·4) in the tOPV-only group (p<0·0001 vs bOPV-only), and 156 of 194 (80·4%, 74·3-85·4) infants in the bOPV-one dose of IPV group (p<0·0001 vs bOPV-only). A further 20 of 193 (10%) infants in the latter group seroconverted 1 week after mOPV2 challenge, resulting in around 98% of infants being seropositive against type 2. After a bOPV-two IPV schedule, all 193 infants (100%, 98·0-100; p<0·0001 vs bOPV-only) seroconverted to type 2. IPV induced small but significant decreases in a composite serotype 2 viral shedding index after mOPV2 challenge. 21 serious adverse events were reported in 20 patients during the study, including two that were judged to be possibly related to the vaccines. Most of the serious adverse events (18 [86%] of 21) and 24 (80%) of the 30 important medical events reported were infections and infestations. No deaths occurred during the study. INTERPRETATION: bOPV provided humoral protection similar to tOPV against polio serotypes 1 and 3. After one or two IPV doses in addition to bOPV, 80% and 100% of infants seroconverted, respectively, and the vaccination induced a degree of intestinal immunity against type 2 poliovirus. FUNDING: Bill & Melinda Gates Foundation.
Asunto(s)
Anticuerpos Neutralizantes/inmunología , Inmunidad Humoral/inmunología , Inmunidad Mucosa/inmunología , Mucosa Intestinal/inmunología , Poliomielitis/prevención & control , Vacuna Antipolio de Virus Inactivados/uso terapéutico , Vacuna Antipolio Oral/uso terapéutico , Esparcimiento de Virus/inmunología , Colombia , República Dominicana , Quimioterapia Combinada , Heces/virología , Femenino , Guatemala , Humanos , Esquemas de Inmunización , Lactante , América Latina , Masculino , Panamá , Poliomielitis/inmunología , Seroconversión , Método Simple CiegoRESUMEN
Salmonella Enteritidis is the main cause of foodborne salmonellosis worldwide. The limited effectiveness of current interventions against this pathogen has been the main incentive to develop new methods for the efficient control of this infection. To investigate the use of DNA vaccines against S. Enteritidis in humans, immune responses stimulated by two plasmids containing the genes designated SEN1002, located in the pathogenicity island SPI-19 and encoding a Hcp protein involved in transport mechanisms, and SEN1395, located in the genomic island ΦSE14 and encoding a protein of a new superfamily of lysozymes, were evaluated. Humoral and cellular responses following intranasal immunization of two groups of BALB/c mice with the plasmids pV1002 and pV1395 plus adjuvant were evaluated and it was observed that the IgG2a/IgG1 ratios were sixfold higher than control groups. Both plasmids stimulated specific secretory IgA production. Increased proliferation of lymphocytes and IFN-γ production were detected in both experimental groups. DNA-vaccinated mice developed protective immunity against a virulent strain of S. Enteritidis, with nearly 2 logs of protection level compared to the negative control values in the spleen. Therefore, DNA vaccines are efficient at stimulating cellular and humoral immune responses at systemic and mucosal levels.
Asunto(s)
Inmunidad Mucosa/inmunología , Salmonelosis Animal/inmunología , Vacunas contra la Salmonella/inmunología , Vacunación , Adyuvantes Inmunológicos/farmacología , Adyuvantes Inmunológicos/uso terapéutico , Animales , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/metabolismo , Femenino , Inmunidad Mucosa/efectos de los fármacos , Inmunoglobulina G/sangre , Ratones , Ratones Endogámicos BALB C , Sistemas de Lectura Abierta , Salmonelosis Animal/microbiología , Salmonella enteritidis , Vacunas de ADN/inmunologíaRESUMEN
Objetivou-se com o presente estudo comparar o efeito de diferentes sorovares de Salmonella na resposta imune local da mucosa do intestino de frangos de corte. Aos sete dias de idade, as aves foram desafiadas com os sorovares S. Enteritidis, S. Typhimurium, S. Senftenberg, S. Mbandaka e S. Minnesota. Foi observado que todos os sorovares testados foram capazes de colonizar o intestino das aves sendo possível o isolamento de Salmonella em suabes de cloaca, 48 h após inoculação. De maneira geral, as aves do grupo controle negativo, que não foram desafiados apresentaram quantidade significativamente menor de células imunológicas na mucosa intestinal do que as aves desafiadas. Porém, verificou-se que os sorovares de Salmonella, utilizados neste estudo, apresentaram diferentes efeitos sobre a dinâmica celular da mucosa do íleo e ceco e afetaram de modo diferente o ganho de peso e ganho médio diário das aves demonstrando distintos graus de patogenicidade. Os sorovares Enteritidis e Typhimurium apresentaram um efeito mais intenso tanto no desempenho quanto na mobilização de células imunológicas na mucosa intestinal de frangos de corte.(AU)
The study was designed to compare the effect of different Salmonella serovars in immune response across the count of CD8+ cells, CD4+ cells, goblet cells and macrophages in the gut mucosa of broilers. During the experimental inoculation at 7 day-old were used Salmonella enterica subspecies enterica sorovars Enteritidis, Typhimurium, Senftenberg, Mbandaka and Minnesota. It was observed that all serovars tested were capable of contaminating the poultry being possible counts of Salmonella in cloacal swabs, 48 h after inoculation and into the crop and cecum, at 14 and 20 day-old. Serovars tested had different effects on broiler performance assessed at 20 days. In the mucosa of the ileum and cecum of broilers, it was observed that some of the serotypes increased CD8 + cells, CD4 + cells, goblet cells and macrophages compared to the negative control group both at 14 and at 20 day-old. S. Enteritidis and S. Typhimurium are the serovars that showed the more intense effect in live performance and in the immune system of birds showing pathogenic characteristic; generally the broilers of the negative control showed significantly less immune cells on the intestinal mucosa than broilers inoculated experimentally. However, it was found that the Salmonella serovars used in this study had different effects on the cellular dynamics of the mucosa of the ileum and cecum and differently affect weight gain and average daily gain of poultry showing different levels of pathogenicity.(AU)
Asunto(s)
Animales , Pollos/inmunología , Salmonella/aislamiento & purificación , Serogrupo , Mucosa Intestinal/fisiopatología , Intestinos/patología , Inmunidad Mucosa/inmunologíaRESUMEN
Objetivou-se com o presente estudo comparar o efeito de diferentes sorovares de Salmonella na resposta imune local da mucosa do intestino de frangos de corte. Aos sete dias de idade, as aves foram desafiadas com os sorovares S. Enteritidis, S. Typhimurium, S. Senftenberg, S. Mbandaka e S. Minnesota. Foi observado que todos os sorovares testados foram capazes de colonizar o intestino das aves sendo possível o isolamento de Salmonella em suabes de cloaca, 48 h após inoculação. De maneira geral, as aves do grupo controle negativo, que não foram desafiados apresentaram quantidade significativamente menor de células imunológicas na mucosa intestinal do que as aves desafiadas. Porém, verificou-se que os sorovares de Salmonella, utilizados neste estudo, apresentaram diferentes efeitos sobre a dinâmica celular da mucosa do íleo e ceco e afetaram de modo diferente o ganho de peso e ganho médio diário das aves demonstrando distintos graus de patogenicidade. Os sorovares Enteritidis e Typhimurium apresentaram um efeito mais intenso tanto no desempenho quanto na mobilização de células imunológicas na mucosa intestinal de frangos de corte.
The study was designed to compare the effect of different Salmonella serovars in immune response across the count of CD8+ cells, CD4+ cells, goblet cells and macrophages in the gut mucosa of broilers. During the experimental inoculation at 7 day-old were used Salmonella enterica subspecies enterica sorovars Enteritidis, Typhimurium, Senftenberg, Mbandaka and Minnesota. It was observed that all serovars tested were capable of contaminating the poultry being possible counts of Salmonella in cloacal swabs, 48 h after inoculation and into the crop and cecum, at 14 and 20 day-old. Serovars tested had different effects on broiler performance assessed at 20 days. In the mucosa of the ileum and cecum of broilers, it was observed that some of the serotypes increased CD8 + cells, CD4 + cells, goblet cells and macrophages compared to the negative control group both at 14 and at 20 day-old. S. Enteritidis and S. Typhimurium are the serovars that showed the more intense effect in live performance and in the immune system of birds showing pathogenic characteristic; generally the broilers of the negative control showed significantly less immune cells on the intestinal mucosa than broilers inoculated experimentally. However, it was found that the Salmonella serovars used in this study had different effects on the cellular dynamics of the mucosa of the ileum and cecum and differently affect weight gain and average daily gain of poultry showing different levels of pathogenicity.
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Animales , Pollos/inmunología , Mucosa Intestinal/fisiopatología , Serogrupo , Salmonella/aislamiento & purificación , Inmunidad Mucosa/inmunología , Intestinos/patologíaRESUMEN
Mucosal immunity consists of innate and adaptive immune responses which can be influenced by systemic immunity. Despite having been the subject of intensive studies, it is not fully elucidated what exactly occurs after HIV contact with the female genital tract mucosa. The sexual route is the main route of HIV transmission, with an increased risk of infection in women compared to men. Several characteristics of the female genital tract make it suitable for inoculation, establishment of infection, and systemic spread of the virus, which causes local changes that may favor the development of infections by other pathogens, often called sexually transmitted diseases (STDs). The relationship of these STDs with HIV infection has been widely studied. Here we review the characteristics of mucosal immunity of the female genital tract, its alterations due to HIV/AIDS, and the characteristics of coinfections between HIV/AIDS and the most prevalent STDs.
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Síndrome de Inmunodeficiencia Adquirida/inmunología , Genitales Femeninos/inmunología , Inmunidad Mucosa/inmunología , Animales , Femenino , Genitales Femeninos/patología , Humanos , Leucocitos/patologíaRESUMEN
Microparticles have been used as promising carriers for in vivo vaccine delivery. However, the processes for immobilizing peptides or proteins on microparticles usually require the use of undesirable compounds and complex protocols. In this work, we propose a new immobilization and delivery system with raw starch microparticles and a starch binding domain (SBD) tag fusion protein. The heat shock protein alpha crystallin from Mycobacterium tuberculosis was used as model. The immunogenicity of the system was investigated in BALB/c mice inoculated with purified Acr-SBDtag protein (pAcr-SBDtag) and starch immobilized Acr-SBDtag protein (µAcr-SBDtag) by oral and intranasal routes. We demonstrated mucosal immunization with the µAcr-SBDtag protein induced systemic antibodies that were predominantly immunoglobulin G2a (IgG2a). An analysis of the cytokines from spleen cells and lung homogenates revealed that loaded microparticles induced the secretion of interferon-γ (INF-γ), suggesting an adjuvant effect from the immobilization. The immune responses induced by immobilized protein were primarily affected by the route of administration. These results demonstrate that the system exhibits the necessary characteristics to improve antigen release and presentation to antigen presenting cells (APCs) in the mucosae. Because no extra adjuvants were used, we posit that the system may be suitable for delivery and presentation to the field of subunit vaccine development.
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Antígenos Bacterianos/administración & dosificación , Antígenos Bacterianos/química , Antígenos/administración & dosificación , Proteínas Bacterianas/administración & dosificación , Proteínas Bacterianas/química , Portadores de Fármacos/química , Microesferas , Almidón/química , Administración Intranasal , Administración Oral , Animales , Antígenos/inmunología , Antígenos/metabolismo , Portadores de Fármacos/administración & dosificación , Femenino , Inmunidad Mucosa/inmunología , Interferón gamma/biosíntesis , Interferón gamma/inmunología , Ratones , Ratones Endogámicos BALB C , Tamaño de la Partícula , Almidón/administración & dosificación , Vacunación , Vacunas de Subunidad/administración & dosificación , Vacunas de Subunidad/inmunologíaRESUMEN
During oral infection, mucosal immunity assumes a predominant role. Here, we addressed the role of mast cells (MCs), which are mainly located in mucosa during oral infection with Toxoplasma gondii, using MC-deficient (W/W(v) ) mice. We show that in the absence of MCs the resistance of W/W(v) mice to oral infection was considerably reduced. W/W(v) mice uniformly succumbed within 15 days of infection after administration of cysts of the ME49 strain of T. gondii. The rapid lethality of T. gondii in W/W(v) mice correlated with a delayed Th1-cell response, since IFN-γ and IL-12 levels peaked in the later phase of the infection. In vitro, BM-derived MCs were able to recognize parasite lysate in a MyD88-dependent way, reaffirming the role of this TLR adapter in immune responses to T. gondii. The importance of MCs in vivo was confirmed when W/W(v) mice reconstituted with BM-derived MCs from control mice retrieved an early strong Th1-cell response and specially a significant IL-12 production. In conclusion, MCs play an important role for the development of a protective immune response during oral infection with T. gondii.
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Inmunidad Mucosa/inmunología , Mastocitos/inmunología , Toxoplasmosis Animal/inmunología , Animales , Técnica del Anticuerpo Fluorescente , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Células TH1/inmunología , Toxoplasma/inmunologíaRESUMEN
The disruption of host-microbe homeostasis at the site of periodontal disease is considered a key factor for disease initiation and progress. While the downstream mechanisms responsible for the tissue damage per se are relatively well-known (involving various patterns of immune response operating toward periodontal tissue destruction), we are only beginning to understand the complexity of host-microbe interactions in the periodontal environment. Unfortunately, most of the research has been focused on the disruption of host-microbe homeostasis instead of focusing on the factors responsible for maintaining homeostasis. In this context, regulatory T-cells (Tregs) comprise a CD4+FOXp3 +T-cell subset with a unique ability to regulate other leukocyte functions to avoid excessive immune activation and its pathological consequences. Tregs act as critical determinants of host-microbe homeostasis, as well as determinants of a balanced host response after the disruption of host-microbe homeostasis by pathogens. In periodontitis, Tregs play a protective role, with their natural recruitment being responsible for conversion of active into inactive lesions. With controlled-release technology, it is now possible to achieve a selective chemoattraction of Tregs to periodontal tissues, attenuating experimental periodontitis evolution due to the local control of inflammatory immune response and the generation of a pro-reparative environment.
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Quimiotaxis de Leucocito/inmunología , Homeostasis/inmunología , Interacciones Huésped-Patógeno/inmunología , Periodontitis/microbiología , Linfocitos T Reguladores/inmunología , Linfocitos T CD4-Positivos/inmunología , Factores de Transcripción Forkhead/inmunología , Humanos , Inmunidad Mucosa/inmunología , Periodontitis/inmunología , Cicatrización de Heridas/inmunologíaRESUMEN
Bacillus subtilis spores have been used as safe and heat-resistant antigen delivery vectors. Nonetheless, the oral administration of spores typically induces weak immune responses to the passenger antigens, which may be attributed to the fast transit through the gastrointestinal tract. To overcome this limitation, we have developed B. subtilis spores capable of binding to the gut epithelium by means of expressing bacterial adhesins on the spore surface. The resulting spores bound to in vitro intestinal cells, showed a longer transit through the mouse intestinal tract, and interacted with Peyer's patch cells. The adhesive spores increased the systemic and secreted antibody responses to the Streptococcus mutans P1 protein, used as a model antigen, following oral, intranasal, and sublingual administration. Additionally, P1-specific antibodies efficiently inhibited the adhesion of the oral pathogen Streptococcus mutans to abiotic surfaces. These results support the use of gut-colonizing B. subtilis spores as a new platform for the mucosal delivery of vaccine antigens.
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Antígenos Bacterianos/administración & dosificación , Bacillus subtilis/inmunología , Vacunas Bacterianas/administración & dosificación , Mucosa Gástrica/inmunología , Esporas Bacterianas/inmunología , Adhesinas Bacterianas/fisiología , Administración Intranasal , Administración Oral , Animales , Anticuerpos Antibacterianos/inmunología , Antígenos Bacterianos/inmunología , Adhesión Bacteriana , Vacunas Bacterianas/inmunología , Western Blotting , Electroforesis en Gel de Poliacrilamida , Mucosa Gástrica/microbiología , Inmunidad Mucosa/inmunología , Ratones , Ratones Endogámicos BALB C , Modelos AnimalesRESUMEN
The Pneumococcal Surface Protein A (PspA) is a promising candidate for the composition of a protein vaccine against Streptococcus pneumoniae. We have previously shown that the whole cell Bordetella pertussis vaccine (wP) is a good adjuvant to PspA, inducing protective responses against pneumococcal infection in mice. In Brazil, wP is administered to children, formulated with diphtheria and tetanus toxoids (DTPw) and aluminum hydroxide (alum) as adjuvant. A single subcutaneous dose of PspA5-DTPlow (a formulation containing PspA from clade 5 and a new generation DTPw, containing low levels of B. pertussis LPS and Alum) induced high levels of systemic anti-PspA5 antibodies in mice and conferred protection against respiratory lethal challenges with two different pneumococcal strains. Here we evaluate the mucosal immune responses against PspA5 as well as the immune responses against the DTP antigens in mice vaccinated with PspA5-DTPlow. Subcutaneous immunization of mice with PspA5-DTPlow induced high levels of anti-PspA5 IgG in the airways but no IgA. In addition, no differences in the influx of cells to the respiratory mucosa, after the challenge, were observed in vaccinated mice, when compared with control mice. The levels of circulating anti-pertussis, -tetanus and -diphtheria antibodies were equivalent in mice vaccinated with DTPlow or PspA5-DTPlow. Antibodies induced by DTPlow or PspA5-DTPlow showed similar ability to neutralize the cytotoxic effects of the diphtheria toxin on Vero cells. Furthermore, combination with PspA5 did not affect protection against B. pertussis and tetanus toxin challenges in mice. Our results support the proposal for a combined PspA-DTP vaccine.