Background: Vascular smooth muscle cells (VSMCs) migration is a critical process during human uterine spiral artery (SpA) remodeling and a successful pregnancy. Extravillous trophoblast cells (EVT) interact with VSMC and enhance their migration, however, the mechanisms by which EVT remodel SpA remain to be fully elucidated. We hypothesize that exosomes released from EVT promote VSMC migration.Methods: JEG-3 and HTR-8/SVneo cell lines were used as models for EVT. Cells were cultured at 37°C and humidified under an atmosphere of 5% CO2-balanced N2 to obtain 8% O2. Cell-conditioned media were collected, and exosomes (exo-JEG-3 and exo- HTR-8/SVneo) isolated by differential and buoyant density centrifugation. The effects of exo-EVT on VSMC migration were established using a real-time, live-cell imaging system (Incucyte™). Exosomal proteins where identified by mass spectrometry and submitted to bioinformatic pathway analysis (Ingenuity software).Results: HTR-8/SVneo cells were significantly more (~30%) invasive than JEG-3 cells. HTR-8/SVneo cells released 2.6-fold more exosomes (6.39 × 108 ± 2.5 × 108 particles/106 cells) compared to JEG-3 (2.86 × 108 ± 0.78 × 108 particles/106 cells). VSMC migration was significantly increased in the presence of exo-JEG-3 and exo-HTR-8/SVneo compared to control (−exosomes) (21.83 ± 0.49 h and 15.57 ± 0.32, respectively, vs. control 25.09 ± 0.58 h, p < 0.05). Sonication completely abolished the effect of exosomes on VSMC migration. Finally, mass spectrometry analysis identified unique exosomal proteins for each EVT cell line-derived exosomes.Conclusion: The data obtained in this study are consistent with the hypothesis that the release, content, and bioactivity of exosomes derived from EVT-like cell lines is cell origin-dependent and differentially regulates VSMC migration. Thus, an EVT exosomal signaling pathway may contribute to SpA remodeling by promoting the migration of VSMC out of the vessel walls.

Host specialization has important consequences for the diversification and ecological interactions of obligate pathogens. The anther-smut disease of natural plant populations, caused by Microbotryum fungi, has been characterized by specialized host-pathogen affinities, which contribute in part to the isolation among these numerous fungal species. This study investigated the molecular variation of Microbotryum pathogens within the geographic and host-specific distributions on wild Dianthus species in southern European Alps. With particular contrast to prior studies on this pathogen genus, a range of overlapping host specificities was observed for four delineated Microbotryum lineages on Dianthus hosts, and their frequent co-occurrence within single-host populations was quantified at local and regional scales. In addition to potential consequences for direct pathogen competition, the sympatry of Microbotryum lineages led to hybridization between them in many populations, and these admixed genotypes were shown to suffer significant meiotic sterility. Therefore, this investigation of the anther-smut fungi reveals how variation in the degrees of host specificity can have major implications for ecological interactions and genetic integrity of differentiated pathogen lineages.

A tenet of contemporary obstetrics is that events that compromise placentation increase the risk of complications of pregnancy and contribute to poor pregnancy outcome. In particular, conditions that affect the invasion of placental cells and remodeling of uterine spiral arteries compromise placental function and the subsequent development of the fetus. Extravillous trophoblast cells (EVTs) proliferate and migrate from the cytotrophoblast in the anchoring villi of the placenta and invade the maternal decidua and myometrium. These cells are localised with uterine uterine spiral arteries and are thought to induce vascular remodeling. A newly identified pathway by which EVTs may regulate vascular remodeling within the uterus is via the release of exosomes. Trophoblast cells release exosomes that mediate aspects of cell-to-cell communication. The aim of this brief commentary is to review the putative role of exosomes released from extravillous trophoblast cells in uterine spiral artery remodeling and, in particular, their role in the aetiology of preeclampsia. Placental exosomes may engage in local cell-to-cell communication between the cell constituents of the placenta and contiguous maternal tissues and/or distal interactions, involving the release of placental exosomes into biological fluids and their transport to a remote site of action.

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Objective To explore the diversity among isolates of the Actinobacillus pleuropneumoniae serovars most common in Australia (serovars 1, 5, 7 and 15) and to examine the Apx toxin profiles in selected representative isolates.Design A total of 250 isolates selected from different farms were examined for their genotypic profiles and a subset of 122 isolates for their toxin profiles.Methods The isolates of serovars 1, 5, 7 and 15 selected for this study came from different farms and different Australian states and were submitted for serotyping to the reference laboratory. The overall diversity of the strains was explored with the enterobacterial repetitive intergenic consensus (ERIC) PCR and the presence of the toxin genes was investigated with a toxin PCR assay.Results Some degree of variation was observed in the ERIC-PCR pattern within all four serovars, ranging from 38% to 61% genetic diversity. When looking at the toxin gene profile and, therefore, the predicted ability to produce the expected toxin pattern, one isolate each of serovars 1 (n = 20) and 7 (n = 47) and 17 isolates of serovar 15 (n = 40) showed variation to the expected gene profile. ConclusionThe variations in toxin gene patterns, as detected by PCR, found in this study could be related to significant changes in the gene sequence or total absence of the gene. Variation in toxin gene sequences has been observed in other countries. This variation in the toxin profile could also explain possible variation in pathogenicity observed in the field.Keywords Actinobacillus pleuropneumoniae; Apx toxin; apx genes; Australia; pigs Abbreviations ERIC, enterobacterial repetitive intergenic consensus; UV, ultraviolet A ctinobacillus pleuropneumoniae is the causative agent of porcine pleuropneumonia and the virulence of the organism is associated with the exotoxins ApxI, ApxII and ApxIII.

Objective To investigate whether an outbreak of Actinobacillus lignieresii was caused by one or multiple strains. Methods Nine isolates of A. lignieresii were obtained from the lymph nodes of 15 affected cattle from two farms to determine whether a single strain was involved. An enterobacterial repetitive insertion consensus sequence (ERIC) PCR was used for genotyping, and the repeats‐in‐toxin genes were analysed by PCR and sequencing. Results Isolates from the two farms belonged to two and three genotypes, with a total of four genotypes detected. Genes of the apxICABD operons of some strains had deletions in the apxIA (~697 bp) and in the apxID (~187 bp) genes. The toxin gene deletions and the ERIC PCR patterns suggested the involvement of different A. lignieresii genotypes. Conclusion There was no evidence that a unique genotype was associated with actinobacillosis on the two farms, confirming that this disease was associated with other contributing factors.

Objective Pleurisy in pigs has economic impacts in the production stage and at slaughter. This study sought to establish if some micro‐organisms can be found in high numbers in lungs with pleurisy by assessing batches of pigs at an abattoir in Queensland Australia. Design Samples of lung (including trachea/bronchus and lymph nodes) from a maximum of 5 pleurisy affected pigs were collected from 46 batches of pigs representing 46 Queensland farms. Procedure Pleurisy‐affected lung areas were cultured by traditional bacteriological methods and bacteria quantified by plate scores. Additionally, tracheal or bronchial swabs and apical lobe fluid were tested for Mycoplasma hyopneumoniae DNA and the superior tracheobronchial lymph nodes were tested for porcine circovirus type 2 DNA by polymerase chain reaction (PCR). All apparently significant bacteria were identified via PCR or sequencing. Typing was undertaken on some of the bacterial isolates. Results The most prevalent pathogens were M. hyopneumoniae, Streptococcus suis and Porcine Circovirus type 2, being found in 34, 38 and 31 batches, respectively. Other bacteria found were Actinobacillus species (29 batches), Pasteurella multocida (24 batches), Mycoplasma flocculare (9 batches), Actinobacillus pleuropneumoniae (7 batches), Mycoplasma hyorhinis (4 batches), Bisgaard Taxon 10 (1 batch), Glaesserella parasuis (1 batch), Streptococcus minor (1 batch) and Streptococcus porcinus (1 batch). Most batches had more than one bacterial species. Conclusion The high percentage of batches infected with S. suis (83%), M. hyopneumoniae (74%) and PCV2 (70%) and clustering by a batch of these pathogens, as well as the presence of many secondary pathogens, suggests synergy between these organisms may have resulted in pleurisy.

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