Exploring the microbiome of two uterine sites in cows.

Bacterial communities in the mammalian reproductive system can be rich and diverse, differing in structure and quantity depending on location. In addition, its microbiome is associated with the state of health of this tract and reproductive success. This study evaluated the microbiome composition of the uterine body (UB) and uterine horn mucosa (UH) samples using 16S rRNA sequencing of samples extracted from cows in the Amazon region. It was observed that four main phyla were shared between the uterine sites: Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria. Linear discriminant analysis effect size and heat tree analysis showed that members of Lachnospiraceae (NK3A20 group) and Oscillospiraceae were significantly more abundant in the UB than in UH. In addition, there are more unique genera in the UB than in the UH. A higher bacterial load in UB than in UH is expected because of the exposure to external factors of UB. However, comparing the site's communities through beta diversity did not generate well-defined clustering. Thus, it can be attributed to the closeness of the sites, which would make the niches similar ecologically and microbiologically. Therefore, this research provides knowledge to understand biomarkers in the prior reproduction period.

Ruminal and feces metabolites associated with feed efficiency, water intake and methane emission in Nelore bulls.

The objectives of this study were twofold: (1) to identify potential differences in the ruminal and fecal metabolite profiles of Nelore bulls under different nutritional interventions; and (2) to identify metabolites associated with cattle sustainability related-traits. We used different nutritional interventions in the feedlot: conventional (Conv; n = 26), and by-product (ByPr, n = 26). Thirty-eight ruminal fluid and 27 fecal metabolites were significantly different (P < 0.05) between the ByPr and Conv groups. Individual dry matter intake (DMI), residual feed intake (RFI), observed water intake (OWI), predicted water intake (WI), and residual water intake (RWI) phenotypes were lower (P < 0.05) in the Conv group, while the ByPr group exhibited lower methane emission (ME) (P < 0.05). Ruminal fluid dimethylamine was significantly associated (P < 0.05) with DMI, RFI, FE (feed efficiency), OWI and WI. Aspartate was associated (P < 0.05) with DMI, RFI, FE and WI. Fecal C22:1n9 was significantly associated with OWI and RWI (P < 0.05). Fatty acid C14:0 and hypoxanthine were significantly associated with DMI and RFI (P < 0.05). The results demonstrated that different nutritional interventions alter ruminal and fecal metabolites and provided new insights into the relationship of these metabolites with feed efficiency and water intake traits in Nelore bulls.

Production and Purification of Cysteine-Rich Leptospiral Virulence-Modifying Proteins with or Without mCherry Fusion.

Recombinant fluorescent fusion proteins are fundamental to advancing many aspects of protein science. Such proteins are typically used to enable the visualization of functional proteins in experimental systems, particularly cell biology. An important problem in biotechnology is the production of functional, soluble proteins. Here we report the use of mCherry-fusions of soluble, cysteine-rich, Leptospira-secreted exotoxins in the PF07598 gene family, the so-called virulence modifying (VM) proteins. The mCherry fusion proteins facilitated the visual detection of pink colonies of the VM proteins (LA3490 and LA1402) and following them through lysis and sequential chromatography steps. CD-spectroscopy analysis confirmed the stability and robustness of the mCherry-fusion protein, with a structure comparable to AlphaFold structural predictions. LA0591, a unique member of the PF07598 gene family that lacks N-terminal ricin B-like domains, was produced without mCherry tag that strengthens the recombinant protein production protocol without fusion protein as well. The current study provides the approaches for the synthesis of 50-125 kDa soluble, cysteine-rich, high-quality fast protein liquid chromatography (FPLC)-purified protein, with and without a mCherry tag. The use of mCherry-fusion proteins enables a streamlined, efficient process of protein production and qualitative and quantitative downstream analytical and functional studies. Approaches for troubleshooting and optimization were evaluated to overcome difficulties in recombinant protein expression and purification, demonstrating biotechnology utility in accelerating recombinant protein production.

An analysis of the cecum microbiome of three breeds of the guinea pig: Andina, Inti, and Peru.

This study investigated the effect of host genetics on the structure and composition of the cecum microbiota of three breeds of guinea pigs: Andina, Inti, and Peru. Fifteen guinea pigs were distributed into three groups according to their breed: Andina (5), Inti (5), and Peru (5). We discovered that four main phyla were shared between the three breeds: Bacteroidota, Firmicutes, Spirochaetota, and Synergistota. Although there were no significant differences in the alpha and beta diversity analysis, we found that the Linear discriminant analysis effect size and the heat tree analysis showed significant differences between the abundance of several taxa present in the cecum microbiome of the three breeds. These results suggest that host genetics could be a factor in the structure and composition of the guinea pig cecum microbiome. In addition, we found unique genera for each breed that have fermentation capacity and, therefore can be analyzed in further studies to determine if there is a functional relationship between them and the breed and its industrial profile.

mCherry Fusion Proteins Facilitate Production of Recombinant, Cysteine-Rich Leptospira interrogans Proteins in Escherichia coli.

Background: Recombinant fluorescent fusion proteins are fundamental to advancing many aspects of protein science. Such proteins are typically used to enable the visualization of functional proteins in experimental systems, particularly cell biology. An important problem in biotechnology is the production of functional, soluble proteins. Here we report the use of mCherry-fusions of soluble, cysteine-rich, Leptospira-secreted exotoxins in the PF07598 gene family, the so-called virulence modifying (VM) proteins. Results: The mCherry fusion proteins facilitated the production of the VM proteins (LA3490 and LA1402) by enabling the visual detection of pink colonies and following them through lysis and sequential chromatography steps. CD-spectroscopy analysis confirmed the stability and robustness of the mCherry-fusion protein, with a structure comparable to AlphaFold structural predictions. LA0591, a unique member of the PF07598 gene family that lacks N-terminal ricin B-like domains, was produced as a tagless protein that strengthens the recombinant protein production protocol. The current study provides the approaches for the synthesis of 50-125 kDa soluble, cysteine-rich, high-quality mCherry tagged or tagless fast protein liquid chromatography (FPLC)-purified protein. Conclusions: The use of mCherry-fusion proteins enables a streamlined, efficient process of protein production and qualitative and quantitative downstream analytical and functional studies. Approaches for troubleshooting and optimization were systemically evaluated to overcome difficulties in recombinant protein expression and purification, demonstrating biotechnology utility in accelerating recombinant protein production.

Comparative analysis of fasting effects on the cecum microbiome in three guinea pig breeds: Andina, Inti, and Peru.

Guinea pigs have historically been used as a food source and are also an important model for studying the human intestines. Fasting is the act of temporarily stopping the intake of food. This process can alter the microbiota of various animals. This study is the first to investigate the impact of fasting on the cecum microbiome of three guinea pig breeds. We investigated the impact of fasting on the microbiome population structure in the cecum of three guinea pig breeds. This was done by sequencing and analyzing the V4 hypervariable region of the 16S rRNA gene in bacterial communities found in cecum mucosa samples. To achieve this, we established two treatment groups (fasting and fed), for each of the three guinea pig breeds: Andina, Inti, and Peru. The study involved twenty-eight guinea pigs, which were divided into the following groups: Andina-fed (five), Andina-fasting (five), Inti-fed (four), Inti-fasting (five), Peru-fed (five), and Peru-fasting (four). The results indicated a significant difference in beta diversity between the treatment groups for the Peru breed (P-value = 0.049), but not for the treatment groups of the Andina and Inti breeds. The dominant phyla across all groups were Firmicutes and Bacteroidetes. We observed variations in the abundance of different taxa in the cecum microbiota when comparing the treatment groups for each breed. Additionally, there was a higher number of unique taxa observed in the fasting groups compared to the fed groups. We discovered that the genus Victivallis was the only one present in all fasting groups across all breeds. Despite the findings, the resilience of the gut microbiome was not challenged in all three breeds, which can lead to disruptive changes that may affect the overall maintenance of the cecum microbiome. Based on the observed differences in the treatment groups of the Peru breed, it can be suggested that fasting has a greater impact on this particular breed.

Differential Allele-Specific Expression Revealed Functional Variants and Candidate Genes Related to Meat Quality Traits in B. indicus Muscle.

Traditional transcriptomics approaches have been used to identify candidate genes affecting economically important livestock traits. Regulatory variants affecting these traits, however, remain under covered. Genomic regions showing allele-specific expression (ASE) are under the effect of cis-regulatory variants, being useful for improving the accuracy of genomic selection models. Taking advantage of the better of these two methods, we investigated single nucleotide polymorphisms (SNPs) in regions showing differential ASE (DASE SNPs) between contrasting groups for beef quality traits. For these analyses, we used RNA sequencing data, imputed genotypes and genomic estimated breeding values of muscle-related traits from 190 Nelore (Bos indicus) steers. We selected 40 contrasting unrelated samples for the analysis (N = 20 animals per contrasting group) and used a beta-binomial model to identify ASE SNPs in only one group (i.e., DASE SNPs). We found 1479 DASE SNPs (FDR ≤ 0.05) associated with 55 beef-quality traits. Most DASE genes were involved with tenderness and muscle homeostasis, presenting a co-expression module enriched for the protein ubiquitination process. The results overlapped with epigenetics and phenotype-associated data, suggesting that DASE SNPs are potentially linked to cis-regulatory variants affecting simultaneously the transcription and phenotype through chromatin state modulation.

FIRST REPORT OF GENUS Cryptosporidium IN CERVIDS SPECIES: Mazama americana, Mazama nana AND Blastocerus dichotomus.

We analyzed Cryptosporidium spp. in fecal samples of wild cervids (Ozotoceros bezoarticus, Blastocerus dichotomus, Mazama nana, Mazama americana, and Mazama bororo) from many Brazilian regions, a fact unprecedented in the literature. Sniffer dogs were used to collect 936 fecal samples of cervids from 14 Brazilian localities. Cervids species were identified using polymerase chain reaction (PCR) performed from genomic DNA extracted from 563 fecal samples of Ozotoceros bezoarticus, Blastocerus dichotomus, Mazama nana, Mazama americana, and Mazama bororo. Cryptosporidium spp. oocyst screening was performed using malachite green negative staining. Nested PCR (nPCR) protocols targeting the 18S rRNA and GP60 genes followed by genetic sequencing were performed for Cryptosporidium spp. detection and Cryptosporidium parvum subtyping, respectively. Nested PCR targeting actin gene and genetic sequencing were performed in samples with non-identified Cryptosporidium species by 18S rRNA amplicon sequencing. The association between the occurrence of Cryptosporidium and the presence of bovines in the same locality was evaluated using Fisher's exact test. The positivity rates of diagnostic methods were compared by McNemar test and the Kappa correlation coefficient. The prevalence rates of Cryptosporidium spp. in cervids were 1.42% (8/563) and 0.36% (2/563) by nPCR and malachite green negative staining, respectively. C. parvum IIaA16G3R1 isolate was identified in three fecal samples from M. americana, two from M. nana and one from B. dichotomus. Cryptosporidium ryanae were found in one sample from B. dichotomus. We identified a new Cryptosporidium genotype, named Cryptosporidium deer genotype BR, from one M. americana fecal sample.

Comparison of the PF07598-Encoded Virulence-Modifying Proteins of L. interrogans and L. borgpetersenii.

Leptospirosis is an emerging infectious disease, with increasing frequency and severity of outbreaks, a changing epidemiology of populations at risk, and the emergence of new strains, serovars, serogroups, and species. Virulence-modifying (VM) proteins encoded by the PF07598 gene family are hypothesized to be Leptospira-secreted exotoxins that mediate the molecular and cellular pathogenesis of severe and fatal leptospirosis. If confirmed experimentally, this concept could revolutionize the treatment, diagnosis, prognosis, and vaccine-mediated prevention of leptospirosis by enabling a novel array of targeted interventions. VM proteins, as with other bacterial-secreted protein exotoxins, mediate their virulence effects by attaching to eukaryotic cells, competing with other microorganisms for limited resources in environmental niches, directly intoxicating target cells, and disrupting their function in the mammalian host. In contrast with the most pathogenic group of Lept ospira, particularly L. interrogans, whose genomes contain 12-15 PF07598 paralogs, strains of the livestock and human pathogen L. borgpetersenii have two PF07598 paralogs. Given the possible non-environmentally mediated transmission of some L. borgpetersenii strains and the much smaller number of VM proteins in this species, their role in infection and disease may well differ from other leptospiral species. Comparison of VM proteins from different clades of pathogenic Leptospira may deepen our understanding of leptospirosis's pathogenesis, leading to novel approaches to ameliorating Leptospira infection in humans and animals.

An in silico, structural, and biological analysis of lactoferrin of different mammals.

Lactoferrin (LF) belongs to the family of transferrins having multifunctional roles associated with the immune system of animals. To follow the aims for this study was selected 20 sequences of LF from mammalian species to evaluate the chemical, biological, and structural properties. Bioinformatics approaches used programs such as MAFFT for sequence alignment; PartitionFinder and MrBayes for phylogenetic approaches; I-TASSER, PROCHECK, Molecular Operating Environment (MOE), SWISS Model server, Peptide DB and Expasy ProtParam to estimate the physicochemical properties, to model the protein and predicted secondary structures. A phylogenic analysis shows species with genetic similarities clustered by complexity and unique grouping between Capra hircus, Macaca mulatta, and Myotis lucifugus, since they presented more amino acids but not overall changes in the iron-binding sites or biological aspects. Structural deviations in these clusters obtained in LF from those species were found in residues 46 (position 406-450), that is part of alpha-helix, and 37 (position 295-331), that is part of the beta-sheets. Our predicted model can be used to investigate more about structural aspects of LF and be applied for medicinal research.

Retraction Note to: Mitochondrial bioenergy alterations in avian HD11 macrophages infected with infectious bronchitis virus.

The Editor-in-Chief has retracted this article [1]. Figures 1A, 1D and 2B (bottom right) are identical with Figures 1A, 1H and 1B respectively in another article [2] which reports a study in a different species. In addition, Table 1 contains data presented in a third article [3], which also reports a study in a different species. The Editor-in-Chief therefore no longer has confidence in the validity of the data and the conclusions drawn. Tereza C. Cardoso disagrees with this retraction. Helena L. Ferreira agrees with this retraction. Sergio E. L. da Silva, Andrea F. Garcia, Felipe E. S. Silva, Roberto Gameiro, Carolina U. F. Fabri and Dielson S. Vieira have not responded to any correspondence about this retraction.

Antimicrobial activity of propolis extract fractions against Staphylococcus spp. isolated from goat mastitis / Atividade antimicrobiana de frações do extrato de própolis frente à Staphylococcus spp. isolados de mastite caprina

The indiscriminate use of antibiotics in the treatment of caprine mastitis causes the appearance of resistant microorganisms, besides leaving residues in milk, putting at risk to human health. In this way, propolis is an alternative in the treatment of diseases because it has antimicrobial activity, mainly because of the presence of flavonoids in its composition. The aim of this study was to evaluate the antimicrobial potential of propolis to Staphylococcus spp. Isolated from cases of goat mastitis and qualify the crude ethanoic extract by high performance liquid chromatography (HPLC). In this study, the minimum bactericidal concentration values of propolis extracts in ethanol, ethyl acetate and hexane showed that the best concentrations capable of promoting the highest mortality of the isolates of Staphylococcus spp. from mastitis in goats, were 6250, 3125 and 1562.5µg/mL, respectively. By the microplate adherence test, it was found that 20.78% isolates were not able to form biofilm, 14.70% were classified as moderate and 64.70% were weak and none as a strong biofilm producer. Propolis in its different diluents was able to affect the formation of biofilm and showed a pronounced marked antimicrobial activity against Staphylococcus spp. strains and may be indicated for use in in vivo studies.(AU)

O uso indiscriminado de antibióticos no tratamento de mastite caprina leva ao desenvolvimento de micro-organismos resistentes que poderão estar presentes em alimentos, colocando em risco a saúde humana. Dessa forma, a própolis surge como uma alternativa para o tratamento de doenças por possuir uma ação antimicrobiana, principalmente pela presença de flavonoides em sua composição. O objetivo desse estudo foi avaliar o potencial antimicrobiano da própolis frente à Staphylococcus spp. isolados de casos de mastite caprina e qualificar o extrato etanoico bruto por cromatografia líquida de alta eficiência (CLAE-DAD). Neste estudo, os valores de concentração bactericida mínima (CBM) dos extratos de própolis em álcool etílico, acetato de etila e hexano nos isolados foram de 6250, 3125 e 1562,5µg/mL, respectivamente. Pelo teste de aderência à microplacas, observou-se que 20,78% dos microorganismos, não foram capazes de formar biofilme, 14,70% foram classificados como moderados, 64,70% em fracos e nenhum como forte produtor de biofilme. A própolis em seus diferentes diluentes foi capaz de afetar a formação de biofilme e apresentou significativa atividade antimicrobiana frente a cepas de Staphylococcus spp., podendo ser indicada para utilização em estudos "in vivo".(AU)

Mitochondrial bioenergy alterations in avian HD11 macrophages infected with infectious bronchitis virus.

To establish an association between mitochondrial dysfunction and apoptosis following infectious bronchitis virus (IBV) infection, HD11 avian macrophage cells were infected with the Massachusetts 41 (M41) strain. Our results show that the M41 strain of IBV induced cytopathic effects followed by the release of new viral particles. Elevated numbers of apoptotic cells were observed at 24, 48 and 72 h post-infection (p.i.). Viral infection was associated with mitochondrial membrane depolarization and reactive oxygen species (ROS) production at all of the examined timepoints p.i. In summary, IBV M41 replication in infected HD11 macrophages seems to induce mitochondrial bioenergy failure, acting as a respiratory chain uncoupler, without compromising viral replication.

Atividade antimicrobiana in vitro do extrato etanólico bruto da folha da Hymenaea martiana Hayne frente às Staphylococcus spp. e avaliação de seu potencial como desinfetante em cabras / In vitro antimicrobial activity of ethanolic extract of Hymenaea martiana Hayne leaf on strains of Staphylococcus spp. and evaluation of its potential as a disinfectant in goats

Este estudo objetivou avaliar a ação antimicrobiana e antisséptica do extrato etanólico bruto da folha da Hymenaea martiana (Jatobá). O estudo foi realizado no Laboratório de Microbiologia e Imunologia da UNIVASF, na cidade de Petrolina-PE. Os extratos foram preparados utilizando diferentes diluentes, sendo estes: álcool etílico absoluto e a água destilada. Em seguida, foi empregada a técnica da Concentração Inibitória Mínima (MIC) e da Concentração Bactericida Mínima (CBM). Todos os ensaios foram realizados em triplicata. A CBM média do extrato diluído em etanol foi de 358µg/µL e do extrato diluído em água destilada foi igual a 520,82µg/mL. Não houve diferença (P<0,05) quanto à inibição bacteriana para o extrato diluído em álcool etílico absoluto ou água destilada autoclavada. Ao comparar a atividade do extrato diluído em álcool etílico absoluto e a relação com a presença do gene blaZ, observou-se que os isolados negativos para o gene pesquisado apresentaram uma CBM igual a 412,3µg/mL, e, quando comparadas aos que foram positivos para o gene blaZ, que foi de 308,80µg/mL, contudo sem diferença estatística. Quanto à inibição das bactérias utilizando extrato aquoso, a atividade foi igual para as bactérias com ou sem o gene (520,82µg/mL). Desse modo, tanto o extrato diluído em álcool etílico absoluto quanto em agua destilada autoclavada demonstrou atividade antimicrobiana, sugerindo que ocorreu extração de substâncias bioativas. Em relação ao potencial antisséptico, H. martiana teve ação pareada com o cloro, contudo aquele agiu mais rapidamente, enquanto o cloro agiu de modo ideal uma hora após a aplicação; ambos os resultados destacam que o extrato etanólico bruto das folhas de H. martiana possui potencial de combate à proliferação de bactérias ambientais e infecciosas, surgindo como uma forma de prevenir a mastite.(AU)

This study aimed to evaluate the antimicrobial and antiseptic action of the crude ethanolic extract of Hymenaea martiana leaves. The study was conducted at the Laboratory of Microbiology and Immunology of UNIVASF, city of Petrolina, state o Pernambuco. The extracts were prepared using different solvents, such as absolute ethyl alcohol and distilled water. Then, Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) techniques were used. All assays were performed in triplicate. The average of MBC extract diluted in ethanol was 358µg/mL, and the extract diluted in distilled water was equal to 520.82µg/mL. There was no difference (P<0.05) and bacterial inhibition to extract diluted in absolute ethanol or autoclaved distilled water. Comparing the activity of the extract diluted in ethanol and the relation with the presence of blaZ gene, it was observed that the negative strains for there searched gene showed a MBC equal to 412.3µg/mL in relation to those that were positive for blaZ gene, that was 308.80µg/µL, and, however, there was no statistical difference. The bacterial inhibition activity using an aqueous extract was equal for the bacteria that had or not the blaZ gene (520.82µg/mL). Thus, the extract diluted in absolute ethanol in autoclaved distilled water as demonstrated antimicrobial activity, suggesting that occurred extraction of bioactive substances. Regarding the antiseptic potential, H. martiana had the same action of chlorine, although, this acted immediately, while the chlorine action happened properly an hour after the application. Both results pointed out that the crude ethanolic extract of H. martiana leaves has potential to combat the proliferation of environmental and infectious bacteria, emerging as a way to prevent mastitis.(AU)

Soluções de óxido de zinco e de nitrato de prata como alternativa para antissepsia de tetos de bovinos (teste in situ) / Solutions of Zinc oxide and silver nitrate as an alternative to bovine udder antisepsis

Este trabalho teve como objetivo analisar o potencial das soluções de óxido de zinco e de nitrato de prata como alternativa para antissepsia de tetos de bovinos (in situ), considerando a escassez de literatura a respeito do uso destes compostos na profilaxia de mastites. Primeiramente foram realizados ensaios de microdiluição e CBM (Concentração Bactericida Mínima) a fim de verificar a atividade antimicrobiana das soluções de óxido de zinco e de nitrato de prata sobre 30 isolados de Staphylococcus spp., obtidos de casos de mastite. Todos os isolados apresentaram sensibilidade às duas soluções testadas, mas a solução de nitrato de prata apresentou menores valores de CBMs (3,05 a 97,65 µg/mL), quando comparada as CBMs da solução de óxido de zinco (97,65 a 6.250 µg/mL). Posteriormente, foram conduzidos os ensaios de antissepsia dos tetos (in situ) através da imersão dos mesmos nas soluções antimicrobianas testadas. Para isso, foram utilizados 40 tetos (n=40) oriundos de vacas abatidas, os quais foram divididos em 4 grupos de 10 tetos, destinados ao teste das solução de óxido de zinco a 3% (30mg/mL), de nitrato e prata 1% (10mg/mL) e seus respectivos controles. Os tetos foram submetidos à contagem de microrganismos mesófilos na superfície dos tetos (UFC/cm2) antes e após a imersão nas soluções testadas. Como resultado, todas as soluções (de óxido de zinco e de nitrato de prata) apresentaram significativa redução de UFC/cm2 até aos 60 minutos após a imersão (M 0' a M 60'). A solução de nitrato de prata apresentou redução de UFC/cm2 significativamente maior, quando comparado ao grupo testado com solução de óxido de zinco. Tais resultados validam o potencial das soluções de óxido de zinco e nitrato de prata para utilização no pré e pós-dipping em vacas leiteiras.(AU)

This study aimed to analyze the zinc oxide and silver nitrate solutions as an alternative antiseptic for cow teats (in situ), considering the lack in the literature about these compounds uses in mastitis prophylaxis. First microdilution tests med and MBC (Minimal Bactericidal Concentration were perfor in order to determine the antimicrobial activity of zinc oxide and silver nitrate solutions over 30 Staphylococcus spp. isolates, obtained from cows with mastitis. All strains tested showed sensitivity to both solutions, but the silver nitrate solution had lower MBC values (3,05 to 97,65ug/ml) compared with zinc oxide solution MBCs (97,65 to 6,250 ug/ml). Subsequently, the antiseptic teat tests were conducted (in situ) by immersing the teats in same antimicrobial solutions tested in the first experiment. Therefore, 40 teats were used (n = 40) originating from slaughtered cows were divided into 4 groups of 10 teats, to test test zinc oxide 3% (30mg/mL) and silver nitrate 1% (10mg/mL) solutions and their respective controls. The teats were submitted to mesophilic count on the teat surface (CFU/cm2) before and after immersion in tested solutions. As a result, all the solutions (zinc oxide and silver nitrate) had a significant reduction in CFU/cm2 until 60 minutes after immersion (M 0' to 60 M'). Silver nitrate solution showed a reduction of CFU/cm2 significantly higher compared to the group treated with zinc oxide solution. These results validate the potential use of zinc oxide and silver nitrate solutions in dairy cows as a pre- and post-dipping antiseptic.(AU)

Expression of miR-155 associated with Toll-like receptors 3, 7, and 9 transcription in the olfactory bulbs of cattle naturally infected with BHV5.

Bovine herpesvirus 5 (BHV5) infection of young cattle is frequently associated with fatal neurological disease and, as such, represents an attractive model for studying the pathogenesis of viral-induced meningoencephalitis. Following replication in the nasal mucosa, BHV5 invades the central nervous system (CNS) mainly through the olfactory pathway. The innate immune response triggered by the host face to virus replication through the olfactory route is poorly understood. Recently, an upregulation of conserved pathogen-associated molecular pattern, as Toll-like receptors (TLRs), has been demonstrated in the CNS of BHV5 experimentally infected cows. A new perspective to understand host-pathogen interactions has emerged elucidating microRNAs (miRNAs) network that interact with innate immune response during neurotropic viral infections. In this study, we demonstrated a link between the expression of TLRs 3, 7, and 9 and miR-155 transcription in the olfactory bulbs (OB) of 16 cows suffering from acute BHV5-induced neurological disease. The OBs were analyzed for viral antigens and genome, miR-155 and TLR 3, 7, and 9 expression considering three major regions: olfactory receptor neurons (ORNs), glomerular layer (GL), and mitral cell layer (ML). BHV5 antigens and viral genomes, corresponding to glycol-C gene, were detected in all OBs regions by fluorescent antibody assay (FA) and PCR, respectively. TLR 3, 7, and 9 transcripts were upregulated in ORNs and ML, yet only ORN layers revealed a positive correlation between TLR3 and miR-155 transcription. In ML, miR-155 correlated positively with all TLRs studied. Herein, our results evidence miR-155 transcription in BHV5 infected OB tissue associated to TLRs expression specifically ORNs which may be a new window for further studies.