Predicting the evolution of clinical skin aging in a multi-ethnic population: Developing causal Bayesian networks using dermatological expertise.

INTRODUCTION: Software to predict the impact of aging on physical appearance is increasingly popular. But it does not consider the complex interplay of factors that contribute to skin aging. OBJECTIVES: To predict the +15-year progression of clinical signs of skin aging by developing Causal Bayesian Belief Networks (CBBNs) using expert knowledge from dermatologists. MATERIAL AND METHODS: Structures and conditional probability distributions were elicited worldwide from dermatologists with experience of at least 15 years in aesthetics. CBBN models were built for all phototypes and for ages ranging from 18 to 65 years, focusing on wrinkles, pigmentary heterogeneity and facial ptosis. Models were also evaluated by a group of independent dermatologists ensuring the quality of prediction of the cumulative effects of extrinsic and intrinsic skin aging factors, especially the distribution of scores for clinical signs 15 years after the initial assessment. RESULTS: For easiness, only models on African skins are presented in this paper. The forehead wrinkle evolution model has been detailed. Specific atlas and extrinsic factors of facial aging were used for this skin type. But the prediction method has been validated for all phototypes, and for all clinical signs of facial aging. CONCLUSION: This method proposes a skin aging model that predicts the aging process for each clinical sign, considering endogenous and exogenous factors. It simulates aging curves according to lifestyle. It can be used as a preventive tool and could be coupled with a generative AI algorithm to visualize aging and, potentially, other skin conditions, using appropriate images.

Respiratory and otolaryngological disorders in Down syndrome from one center in Brazil.

Down syndrome (DS) is the most common chromosomal condition. Anatomical and functional variations in the upper and lower airways are component manifestations of the syndrome and increase the risk of various medical problems. The objective of this study was to determine the prevalence of otorhinolaryngological and respiratory diseases in a DS outpatient clinic over a 3-year period. Medical records data from 1207 patients were retrospectively reviewed. Newborn Hearing Screening was positive in 7.1% of patients. Brainstem auditory evoked potential was performed in 1101 children and showed a hearing loss of 19.8% in the first year. It was positive in 21% of 1021 exams. Audiometry was altered in 64 of 994 exams (6.4%), showing a conductive loss in 90%. Adenotonsillectomy was performed in 308 (25.5%) patients, and 169 (14.0%) required serous otitis ventilation tubes. Asthma was observed in 140 (11.6%) patients, and allergic rhinitis in 544 (56.6%). There were hospitalizations for invasive infection in 480 (39.8%) children, and two (0.2%) patients had severe septicemia from pulmonary focus. Five (0.4%) infants had laryngotracheomalacia, and one patient had anomalous right tracheal bronchus. Recognizing the prevalence of respiratory and otorhinolaryngological disorders in patients with DS allows the promotion of optimal follow-up and early treatment, preventing the development of sequelae.

Perinatal maternal antibiotic exposure augments lung injury in offspring in experimental bronchopulmonary dysplasia.

During the newborn period, intestinal commensal bacteria influence pulmonary mucosal immunology via the gut-lung axis. Epidemiological studies have linked perinatal antibiotic exposure in human newborns to an increased risk for bronchopulmonary dysplasia, but whether this effect is mediated by the gut-lung axis is unknown. To explore antibiotic disruption of the newborn gut-lung axis, we studied how perinatal maternal antibiotic exposure influenced lung injury in a hyperoxia-based mouse model of bronchopulmonary dysplasia. We report that disruption of intestinal commensal colonization during the perinatal period promotes a more severe bronchopulmonary dysplasia phenotype characterized by increased mortality and pulmonary fibrosis. Mechanistically, metagenomic shifts were associated with decreased IL-22 expression in bronchoalveolar lavage and were independent of hyperoxia-induced inflammasome activation. Collectively, these results demonstrate a previously unrecognized influence of the gut-lung axis during the development of neonatal lung injury, which could be leveraged to ameliorate the most severe and persistent pulmonary complication of preterm birth.

TGR5 signaling mitigates parenteral nutrition-associated liver disease.

Bile acid receptors regulate the metabolic and immune functions of circulating enterohepatic bile acids. This process is disrupted by administration of parenteral nutrition (PN), which may induce progressive hepatic injury for unclear reasons, especially in the newborn, leading to PN-associated liver disease. To explore the role of bile acid signaling on neonatal hepatic function, we initially observed that Takeda G protein receptor 5 (TGR5)-specific bile acids were negatively correlated with worsening clinical disease markers in the plasma of human newborns with prolonged PN exposure. To test our resulting hypothesis that TGR5 regulates critical liver functions to PN exposure, we used TGR5 receptor deficient mice (TGR5-/-). We observed PN significantly increased liver weight, cholestasis, and serum hepatic stress enzymes in TGR5-/- mice compared with controls. Mechanistically, PN reduced bile acid synthesis genes in TGR5-/-. Serum bile acid composition revealed that PN increased unconjugated primary bile acids and secondary bile acids in TGR5-/- mice, while increasing conjugated primary bile acid levels in TGR5-competent mice. Simultaneously, PN elevated hepatic IL-6 expression and infiltrating macrophages in TGR5-/- mice. However, the gut microbiota of TGR5-/- mice compared with WT mice following PN administration displayed highly elevated levels of Bacteroides and Parabacteroides, and possibly responsible for the elevated levels of secondary bile acids in TGR5-/- animals. Intestinal bile acid transporters expression was unchanged. Collectively, this suggests TGR5 signaling specifically regulates fundamental aspects of liver bile acid homeostasis during exposure to PN. Loss of TGR5 is associated with biochemical evidence of cholestasis in both humans and mice on PN.NEW & NOTEWORTHY Parenteral nutrition is associated with deleterious metabolic outcomes in patients with prolonged exposure. Here, we demonstrate that accelerated cholestasis and parental nutrition-associated liver disease (PNALD) may be associated with deficiency of Takeda G protein receptor 5 (TGR5) signaling. The microbiome is responsible for production of secondary bile acids that signal through TGR5. Therefore, collectively, these data support the hypothesis that a lack of established microbiome in early life or under prolonged parenteral nutrition may underpin disease development and PNALD.

Monoclonal antibodies against LipL32 confer prophylactic protection against lethal leptospirosis challenge in animal model.

Leptospirosis is a widespread zoonotic disease caused by pathogenic spirochetes of the genus Leptospira. The commercially available vaccines are bacterins that offer limited protection, short-term effect, and serovar-specific immunity. The development of novel immunization strategies is crucial to control the infection and decrease the chances of new outbreaks. In this study, purified monoclonal antibodies (mAbs) anti-LipL32 (1D9 and mAb3) were evaluated by their capacity to bind and neutralize the pathogen improving host survival. For that, an in vitro growth inhibition assay, and in vivo passive immunization were performed in animal model. Syrian hamsters were passively immunized by three different strategies. Hamsters immunized with mAb3 6 h prior to the lethal challenge showed a significantly higher survival rate of 61.1%, and a significant reduction in tissue damage in the lungs. Cumulatively, our results showed that anti-LipL32 mAbs inhibited the growth of L. interrogans in vitro, and that passive immunization offered significant protection in animal model when administered prior to infection.

Fungi form interkingdom microbial communities in the primordial human gut that develop with gestational age.

Fungal and bacterial commensal organisms play a complex role in the health of the human host. Expansion of commensal ecology after birth is a critical period in human immune development. However, the initial fungal colonization of the primordial gut remains undescribed. To investigate primordial fungal ecology, we performed amplicon sequencing and culture-based techniques of first-pass meconium, which forms in the intestine prior to birth, from a prospective observational cohort of term and preterm newborns. Here, we describe fungal ecologies in the primordial gut that develop complexity with advancing gestational age at birth. Our findings suggest homeostasis of fungal commensals may represent an important aspect of human biology present even before birth. Unlike bacterial communities that gradually develop complexity, the domination of the fungal communities of some preterm infants by Saccromycetes, specifically Candida, may suggest a pathologic association with preterm birth.-Willis, K. A., Purvis, J. H., Myers, E. D., Aziz, M. M., Karabayir, I., Gomes, C. K., Peters, B. M., Akbilgic, O., Talati, A. J., Pierre, J. F. Fungi form interkingdom microbial communities in the primordial human gut that develop with gestational age.

Ophthalmological abnormalities in Down syndrome among Brazilian patients.

Down syndrome is the most common chromosomal disorder, affecting 1/700 live births. Among the clinical findings, one constant concern is the high prevalence of visual disorders that, if left untreated, can negatively affect child development. The aim of this study was to determine the prevalence of ophthalmological findings among patients who attended an outpatient clinic for patients with Down syndrome in southern Brazil between 2005 and 2016. A cross-sectional study including 1,207 patients medical records were done, which 492 (40.8%) had some ophthalmological disorder. These data were subjected to descriptive analysis using Statistica software. Among the 492 patients with any ophthalmological disease, the need for glasses was found in 434 (36%) patients, keratoconus in 254 (42.1%), congenital cataract in 27 (15.1%), nasolacrimal duct obstruction in 25 (2.0%), strabismus in 22 (1.9%), nystagmus in four (0.3%), and juvenile cataract in two (0.2%). Two young adults with keratoconus underwent corneal transplantation. Although the prevalence of an ophthalmological disease among the present sample (40.8%) was lower than described in the current literature, it still reinforced the importance of routine and early evaluations in infants. These should begin at 6 months of age and be repeated half-year until 2 years old, annually until 7 years old, biennial in adolescents, and triennial in adults and elderly. Our findings of a high frequency of keratoconus support a detailed corneal study in such patients for early detection and treatment.

Sex Matters: Male Hamsters Are More Susceptible to Lethal Infection with Lower Doses of Pathogenic Leptospira than Female Hamsters.

A somewhat contradictory published body of evidence suggests that sex impacts severity outcomes of human leptospirosis. In this study, we used an acute animal model of disease to analyze leptospirosis in male and female hamsters infected side by side with low but increasing doses of Leptospira interrogans serovar Copenhageni. We found that male hamsters were considerably more susceptible to leptospirosis, given that only 6.3% survived infection, whereas 68.7% of the females survived the same infection doses. In contrast to the females, male hamsters had high burdens of L. interrogans in kidney and high histopathological scores after exposure to low infection doses (∼103 bacteria). In hamsters infected with higher doses of L. interrogans (∼104 bacteria), differences in pathogen burdens as well as cytokine and fibrosis transcript levels in kidney were not distinct between sexes. Our results indicate that male hamsters infected with L. interrogans are more susceptible to severe leptospirosis after exposure to lower infectious doses than females.

Disruption of brain-derived neurotrophic factor production from individual promoters generates distinct body composition phenotypes in mice.

Brain-derived neurotrophic factor (BDNF) is a key neuropeptide in the central regulation of energy balance. The Bdnf gene contains nine promoters, each producing specific mRNA transcripts that encode a common protein. We sought to assess the phenotypic outcomes of disrupting BDNF production from individual Bdnf promoters. Mice with an intact coding region but selective disruption of BDNF production from Bdnf promoters I, II, IV, or VI (Bdnf-e1-/-, -e2-/-, -e4-/-, and -e6-/-) were created by inserting an enhanced green fluorescent protein-STOP cassette upstream of the targeted promoter splice donor site. Body composition was measured by MRI weekly from age 4 to 22 wk. Energy expenditure was measured by indirect calorimetry at 18 wk. Food intake was measured in Bdnf-e1-/- and Bdnf-e2-/- mice, and pair feeding was conducted. Weight gain, lean mass, fat mass, and percent fat of Bdnf-e1-/- and Bdnf-e2-/- mice (both sexes) were significantly increased compared with wild-type littermates. For Bdnf-e4-/- and Bdnf-e6-/- mice, obesity was not observed with either chow or high-fat diet. Food intake was increased in Bdnf-e1-/- and Bdnf-e2-/- mice, and pair feeding prevented obesity. Mutant and wild-type littermates for each strain (both sexes) had similar total energy expenditure after adjustment for body composition. These findings suggest that the obesity phenotype observed in Bdnf-e1-/- and Bdnf-e2-/- mice is attributable to hyperphagia and not altered energy expenditure. Our findings show that disruption of BDNF from specific promoters leads to distinct body composition effects, with disruption from promoters I or II, but not IV or VI, inducing obesity.

Phenotypic and Molecular Characterization of Leptospira interrogans Isolated from Canis familiaris in Southern Brazil.

Leptospirosis is a zoonotic disease caused by pathogenic spirochetes from the genus Leptospira, which includes 20 species and more than 300 serovars. Canines are important hosts of pathogenic leptospires and can transmit the pathogen to humans via infected urine. Here, we report the phenotypic and molecular characterization of Leptospira interrogans isolated from Canis familiaris in Southern Brazil. The isolated strain was characterized by variable-number tandem-repeats analysis as L. interrogans, serogroup Icterohaemorrhagiae. In addition, the isolate was recognized by antibodies from human and canine serum samples previously tested by microscopic agglutination test. Ultimately, the expression of membrane-associated antigens (LipL32 and leptospiral immunoglobulin-like proteins) from pathogenic leptospires using monoclonal antibodies was detected by indirect immunofluorescence assay. In conclusion, identification of new strains of Leptospira can help in the diagnosis and control of leptospirosis.

Enzyme immunoassays (EIA) for serodiagnosis of human leptospirosis: specific IgG3/IgG1 isotyping may further inform diagnosis of acute disease.

The laborious microscopic agglutination test (MAT) is the gold standard serologic test for laboratory diagnosis of leptospirosis. We developed EIA based serologic assays using recombinant proteins (rLigA, rLigB, rLipL32) and whole-cell extracts from eight Leptospira serovars as antigen and assessed the diagnostic performance of the new assay within each class, against MAT positive (MAT+) human sera panels from Portugal/PT (n = 143) and Angola/AO (n = 100). We found that a combination of recombinant proteins rLigA, rLigB and rLipL32 correctly identified antigen-specific IgG from patients with clinical and laboratory confirmed leptospirosis (MAT+) with 92% sensitivity and ~ 97% specificity (AUC 0.974) in serum from the provinces of Luanda (LDA) and Huambo (HBO) in Angola. A combination of whole cell extracts of L. interrogans sv Copenhageni (LiC), L. kirschneri Mozdok (LkM), L. borgpetersenii Arborea (LbA) and L. biflexa Patoc (LbP) accurately identified patients with clinical and laboratory confirmed leptospirosis (MAT+) with 100% sensitivity and ~ 98% specificity for all provinces of Angola and Portugal (AUC: 0.997 for AO/LDA/HBO, 1.000 for AO/HLA, 0.999 for PT/AZ and 1.000 for PT/LIS). Interestingly, we found that MAT+ IgG+ serum from Angola had a significantly higher presence of IgD and that IgG3/IgG1 isotypes were significantly increased in the MAT+ IgG+ serum from Portugal. Given that IgM/IgD class and IgG3/IgG1 specific isotypes are produced in the earliest course of infection, immunoglobulin G isotyping may be used to inform diagnosis of acute leptospirosis. The speed, ease of use and accuracy of EIA tests make them excellent alternatives to the laborious and expensive MAT for screening acute infection in areas where circulating serovars of pathogenic Leptospira are well defined.

Chronic intake of high dietary sucrose induces sexually dimorphic metabolic adaptations in mouse liver and adipose tissue.

Almost all effective treatments for non-alcoholic fatty liver disease (NAFLD) involve reduction of adiposity, which suggests the metabolic axis between liver and adipose tissue is essential to NAFLD development. Since excessive dietary sugar intake may be an initiating factor for NAFLD, we have characterized the metabolic effects of liquid sucrose intake at concentrations relevant to typical human consumption in mice. We report that sucrose intake induces sexually dimorphic effects in liver, adipose tissue, and the microbiome; differences concordant with steatosis severity. We show that when steatosis is decoupled from impairments in insulin responsiveness, sex is a moderating factor that influences sucrose-driven lipid storage and the contribution of de novo fatty acid synthesis to the overall hepatic triglyceride pool. Our findings provide physiologic insight into how sex influences the regulation of adipose-liver crosstalk and highlight the importance of extrahepatic metabolism in the pathogenesis of diet-induced steatosis and NAFLD.

Time of Feeding Alters Obesity-Associated Parameters and Gut Bacterial Communities, but Not Fungal Populations, in C57BL/6 Male Mice.

BACKGROUND: Fasting and timed feeding strategies normalize obesity parameters even under high-fat dietary intake. Although previous work demonstrated that these dietary strategies reduce adiposity and improve metabolic health, limited work has examined intestinal microbial communities. OBJECTIVES: We determined whether timed feeding modifies the composition of the intestinal microbiome and mycobiome (yeast and fungi). METHODS: Male C57BL/6 mice were fed a high-fat diet (HF) for 6 wk. Animals were then randomly assigned to the following groups (n = 8-10/group): 1) HF ad libitum; 2) purified high-fiber diet (Daniel Fast, DF); 3) HF-time-restricted feeding (TRF) (6 h); 4) HF-alternate-day fasting (ADF); or 5) HF at 80% total caloric restriction (CR). After 8 wk, obesity and gut parameters were characterized. We also examined changes to the gut microbiome and mycobiome before, during, and following dietary interventions. RESULTS: Body mass gain was reduced with all restricted dietary groups. HF-fed microbiota displayed lower α-diversity along with reduced phylum levels of Bacteroidetes and increased Firmicutes. Animals switched from HF to DF demonstrated a rapid transition in bacterial taxonomic composition, α-, and ß-diversity that initially resembled HF, but was distinct after 4 and 8 wk of DF feeding. Time-or calorie-restricted HF-fed groups did not show changes at the phylum level, but α-diversity was increased, with specific genera altered. Six weeks of HF feeding reduced various fungal populations, particularly Alternaria, Aspergillus, Cladosporium, and Talaromyces, and increased Candida, Hanseniaspora, and Kurtzmaniella. However, 8 wk of intervention did not change the fungal populations, with the most abundant genera being Candida, Penicillium, and Hanseniaspora. CONCLUSIONS: These data suggest that timed-feeding protocols and diet composition do not significantly affect the gut fungal community, despite inducing measurable shifts in the bacterial population that coincide with improvements in metabolism.

Bile Diversion Improves Metabolic Phenotype Dependent on Farnesoid X Receptor (FXR).

OBJECTIVE: The current study investigated whether bile diversion (BD) improves metabolic phenotype under farnesoid X receptor (FXR) deficiency. METHODS: BD was performed in high-fat diet (HFD)-fed FXR knockout (FXRko) and wild-type (WT) animals. Metabolic phenotypes, circulating enteroendocrine hormones, total bile acids (BAs) and BA composition, and cecal gut microbiota were analyzed. RESULTS: FXR-deficient mice were resistant to HFD-induced obesity; however, FXR-deficient mice also developed hyperglycemia and exhibited increased liver weight, liver steatosis, and circulating triglycerides. BD increased circulating total BAs and taurine-b-muricholic acid, which were in line with normalized hyperglycemia and improved glucose tolerance in HFD-fed WT mice. FXR deficiency also increased total BAs and taurine-b-muricholic acid, but these animals remained hyperglycemic. While BD improved metabolic phenotype in HFD-fed FXRko mice, these improvements were not as effective as in WT mice. BD increased liver expression of fibroblast growth factor 21 and peroxisome proliferator-activated receptor γ coactivator-1ß and elevated circulating glucagon-like peptide-1 levels in WT mice but not in FXRko mice. FXR deficiency altered gut microbiota composition with a specific increase in phylum Proteobacteria that may act as a possible microbial signature of some diseases. These cellular and molecular changes in FXRko mice may contribute to resistance toward improved metabolism. CONCLUSIONS: FXR signaling plays a pivotal role in improved metabolic phenotype following BD surgery.

Vitamin C Prevents Ultraviolet-induced Pigmentation in Healthy Volunteers: Bayesian Meta-analysis Results from 31 Randomized Controlled versus Vehicle Clinical Studies.

Background: Repeated nonextreme sun exposures induce skin pigmentation by increasing melanin production and by oxidizing preexisting melanin and melanin precursors. This leads to skin disorders and skin color heterogeneity such as hyperpigmented spots. Objective: We assessed 31 randomized, controlled clinical trials to determine the potential of vitamin C to limit ultraviolet (UV) daylight-induced pigmentation, considering dose response and different skin type populations (Caucasian and Chinese). Materials and Methods: Thirty-one intraindividual, randomized, controlled clinical trials involving Caucasian and Chinese subjects (15-35 healthy male or female volunteers per study, 741 total volunteers) 18 to 50 years of age with Phototype III and individual typology angle (ITA) value between 28 and 49 degrees were analyzed. The 31 studies assessed the potential of vitamin C (formulated with the copolymer Styrène-Anhydride Maléique [SMA]) to decrease pigmentation induced by UV daylight exposure. Results were combined using a Bayesian meta-analysis to provide probabilistic evidence of the effects of vitamin C by dose and population. Results: Vitamin C was effective in reducing pigmentation induced by UV daylight-simulated expositions (4 days at 0.75 Individual Minimal Erythemal Dose [MEDi]) in a dose-dependent manner. During the depigmentation phase, no additive value was provided by the vitamin C, suggesting that the lightening properties described in the literature for vitamin C correspond to an antipigmenting quality rather than a depigmenting effect. Conclusion: Vitamin C is a valuable and safe dermocosmetic antipigmenting compound with a strong effect at 10% possibly useful in preventing signs of photoaging.

A novel chimeric protein composed of recombinant Mycoplasma hyopneumoniae antigens as a vaccine candidate evaluated in mice.

Enzootic Pneumonia (EP) is caused by the Mycoplasma hyopneumoniae pathogenic bacteria, and it represents a significant respiratory disease that is responsible for major economic losses within the pig industry throughout the world. The bacterins that are currently commercially available have been proven to offer only partial protection against M. hyopneumoniae, and the development of more efficient vaccines is required. Several recombinant antigens have been evaluated via different immunization strategies and have been found to be highly immunogenic. This work describes the construction and immunological characterization of a multi-antigen chimera composed of four M. hyopneumoniae antigens: P97R1, P46, P95, and P42. Immunogenic regions of each antigen were selected and combined to encode a single polypeptide. The gene was cloned and expressed in Escherichia coli, and the chimeric protein was recognized by specific antibodies against each subunit, as well as by convalescent pig sera. The immunogenic properties of the chimera were then evaluated in a mice model through two recombinant vaccines that were formulated as follows: (1) purified chimeric protein plus adjuvant or (2) recombinant Escherichia coli bacterin. The immune response induced in BALB/c mice immunized with each formulation was characterized in terms of total IgG levels, IgG1, and IgG2a isotypes against each antigen present in the chimera. The results of the study indicated that novel chimeric protein is a potential candidate for the future development of a more effective vaccine against EP.

Human and animal leptospirosis in Southern Brazil: A five-year retrospective study.

BACKGROUND: Leptospirosis is an emerging zoonosis attributed to multiple reservoirs. Climatic conditions influence the transmission of pathogenic leptospires, which require warm and humid conditions for survival. The influence of seasonality in human and animal leptospirosis in the subtropical region of Brazil remains poorly understood. METHODS: We performed a retrospective study to describe the patterns of human and animal exposure to leptospirosis and their association with precipitation events in Southern Brazil. Rainfall data were obtained from satellite images. Serum samples were tested using the microscopic agglutination test (MAT); samples with titer ≥ 100 were defined as seroreactive. Linear regression and Pearson's correlation were performed to assess whether there is a relationship between these variables. RESULTS: We found that precipitation events were not significantly associated with the exposure to leptospirosis in humans or animal species, except for dogs. The interspecies analysis revealed an association between canine and human exposure to leptospirosis. Leptospira kirschneri serovar Butembo (serogroup Autumnalis) presented the highest seroreactivity in humans. CONCLUSION: This study provides valuable insights in human and animal leptospirosis in Southern Brazil. These insights will be essential to design intervention measures directed to reduce disease dissemination.

The Myeloid U937 Skin Sensitization Test (U-SENS) addresses the activation of dendritic cell event in the adverse outcome pathway for skin sensitization.

The U-SENS™ assay, formerly known as MUSST (Myeloid U937 Skin Sensitization Test), is an in vitro method to assess skin sensitization. Dendritic cell activation following exposure to sensitizers was modelled in the U937 human myeloid cell line by measuring the induction of the expression of CD86 by flow cytometry. The predictive performance of U-SENS™ was assessed via a comprehensive comparison analysis with the available human and LLNA data of 175 substances. U-SENS™ showed 79% specificity, 90% sensitivity and 88% accuracy. A four laboratory ring study demonstrated the transferability, reliability and reproducibility of U-SENS™, with a reproducibility of 95% within laboratories and 79% between-laboratories, showing that the U-SENS™ assay is a promising tool in a skin sensitization risk assessment testing strategy.

The Mycoplasma hyopneumoniae recombinant heat shock protein P42 induces an immune response in pigs under field conditions.

Enzootic pneumonia (EP), resulting from Mycoplasma hyopneumoniae infection is one of the most prevalent diseases in pigs and is a major cause of economic losses to the swine industry worldwide. EP is often controlled by vaccination with inactivated, adjuvanted whole-cell bacterin. However, these bacterins provide only partial protection and do not prevent M. hyopneumoniae colonization. Attempts to develop vaccines that are more efficient have made use of the recombinant DNA technology. The objective of this study was to assess the potential of recombinant M. hyopneumoniae heat shock protein P42 in vaccine preparations against EP, using piglets housed under field conditions in a M. hyopneumoniae-positive farm. The cellular and humoral immune responses were elicited after a single intramuscular inoculation of rP42 in an oil-based adjuvant, or in conjunction with whole-cell vaccine preparation. The production of INF-γ and IL-10 cytokines was quantified in the supernatant of the cultured mononuclear cells. The rP42 emulsified in oil-based adjuvant was able to trigger a strong humoral immune response. Further, it induced a cellular immune response, accompanied by the production of antibodies that reacted with the native M. hyopneumoniae protein. The rP42 mediated induction of cellular and humoral immune response in the host suggests that rP42 emulsified in an oil-based adjuvant holds promise as an effective recombinant subunit vaccine against EP.

Local and systemic immune responses induced by a recombinant chimeric protein containing Mycoplasma hyopneumoniae antigens fused to the B subunit of Escherichia coli heat-labile enterotoxin LTB.

A multi-antigen chimera composed of three antigens of Mycoplasma hyopneumoniae (R1, P42, and NrdF) and the mucosal adjuvant Escherichia coli heat-labile enterotoxin B subunit (LTB) was constructed, and its antigenic and immunogenic properties were evaluated in mice and pigs. In addition, we compared the effect of the fusion and co-administration of these proteins in mice. Antibodies against each subunit recognized the chimeric protein. Intranasal and intramuscular immunization of mice with the chimeric protein significantly increased IgG and IgA levels in the serum and tracheobronchial lavages, respectively, against some of the antigens present in the chimeric. Swine immunized with the chimeric protein developed an immune response against all M. hyopneumoniae antigens present in the fusion with a statistically significant difference (P<0.05). The adjuvant rLTB enhanced the immune response in both fused and co-administered antigens; however, better results were obtained with the chimeric protein. This multi-antigen is a promising vaccine candidate that may help control M. hyopneumoniae infection.