Contemporary approaches to modelling the consumer

Modelling is an exciting area of consumer psychology, with application to many problems and contexts. We have covered the founding principles and objectives of the modelling process, which have remained largely unchanged over the course of time. What has changed are the constant innovations in methodologies (especially analyses) and software development that keep pushing the boundaries of modelling. These developments have given rise to some interesting opportunities to work in multidisciplinary teams (especially around exploiting big data in a meaningful way) and to the opening up of new and innovative areas of research in understanding the consumer

Complete Genome Sequence of Chlamydia abortus MRI-10/19, Isolated from a Sheep Vaccinated with the Commercial Live C. abortus 1B Vaccine Strain

We report the complete genome sequence of Chlamydia abortus MRI-10/19, recovered from the infected placenta of a sheep that had been vaccinated with the commercial live attenuated C. abortus 1B vaccine strain. Comparative analysis revealed 1 single nucleotide polymorphism (SNP) difference and 4 indels compared to the vaccine strain.EEA MercedesFil: Livingstone, Morag. Moredun Research Institute; Reino UnidoFil: Caspe, Sergio Gaston. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mercedes; ArgentinaFil: Caspe, Sergio Gaston. Moredun Research Institute; Reino UnidoFil: Longbottom, David. Moredun Research Institute; Reino Unid

The extent of placental pathology is negatively correlated to birth weight in ewes infected with the wild-type strain of Chlamydia abortus

The placenta is the organ that allows the exchange of oxygen and nutrients between maternal and foetal blood, supplying the requirements of the growing foetus. Consequently, any factor that alters placental integrity may affect foetal nutrition, viability and lamb birth weight. Reproductive diseases, such as ovine enzootic abortion (OEA), impact on foetal viability due to the reduction in the functional area for maternofoetal exchange. This study aimed to consider the impact of pathological features of OEA placental lesions on lamb birth weight and indirectly on foetal viability. To investigate the relationship between birth weight and various OEA-related parameters, data from 562 lambs/foetuses from animals experimentally challenged with Chlamydia abortus strain S26/3 and from uninfected animals were analysed. The parameters investigated included the number of foetuses/lambs delivered (single/multiple), foetus/lamb sex, length of gestation, the proportion of placentas affected by lesions (percentage of gross placental pathology), foetal viability (live/aborted) and the number of C. abortus organisms shed in post-parturition vaginal excretions. The results suggest that the length of gestation and the proportion of placentas affected by lesions are the main contributors to birth weight variability, whereas the other factors, including foetal viability (live or aborted outcomes), were found to be less relevant co-variables. The study determined the strongest positive and negative correlations between birth weight were with the length of gestation and the extent of placental pathology, respectively. These results may indicate that economic losses associated with OEA infections result not only from aborted foetuses but also from the surviving lambs that are born weaker and consequently are more susceptible to diseases.EEA MercedesFil: Caspe, Sergio Gaston. Moredun Research Institute; Reino UnidoFil: Caspe, Sergio Gaston. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mercedes; ArgentinaFil: Caspe, Sergio Gaston. University of Edinburgh. Royal (Dick) School of Veterinary Studies; Reino UnidoFil: Palarea-Albaladejo, Javier. Biomathematics & Statistics Scotland; Reino UnidoFil: Palarea-Albaladejo, Javier. University of Girona. Deparment of Computer Sciences, Applied Mathematics and Statistics; EspañaFil: Livingstone, Morag. Moredun Research Institute; Reino UnidoFil: Wattegedera, Sean Ranjan. Moredun Research Institute; Reino UnidoFil: Milne, Elspeth. University of Edinburgh. Royal (Dick) School of Veterinary Studies; Reino UnidoFil: Sargison, Neil Donald. University of Edinburgh. Royal (Dick) School of Veterinary Studies; Reino UnidoFil: Longbottom, David. Moredun Research Institute; Reino Unid

MAPK Activation Is Essential for Waddlia chondrophila Induced CXCL8 Expression in Human Epithelial Cells

BackgroundWaddlia chondrophila (W. chondrophila) is an emerging agent of respiratory and reproductive disease in humans and cattle. The organism is a member of the order Chlamydiales, and shares many similarities at the genome level and in growth studies with other well-characterised zoonotic chlamydial agents, such as Chlamydia abortus (C. abortus). The current study investigated the growth characteristics and innate immune responses of human and ruminant epithelial cells in response to infection withW. chondrophila.MethodsHuman epithelial cells (HEp2) were infected withW. chondrophila for 24h. CXCL8 release was significantly elevated in each of the cell lines by active-infection with liveW. chondrophila, but not by exposure to UV-killed organisms. Inhibition of either p38 or p42/44 MAPKsignificantly inhibited the stimulation of CXCL8 release in each of the cell lines. To determine the pattern recognition receptor through which CXCL8 release was stimulated, wildtype HEK293 cells which express no TLR2, TLR4, NOD2 and only negligible NOD1 wereinfected with live organisms. A significant increase in CXCL8 was observed. Conclusions/SignificanceW. chondrophila actively infects and replicates within both human and ruminant epithelial cells stimulating CXCL8 release. Release of CXCL8 is significantly inhibited by inhibition of either p38 or p42/44 MAPK indicating a role for this pathway in the innate immune response toW. chondrophila infection.W. chondrophila stimulation of CXCL8 secretion in HEK293 cells indicates that TLR2, TLR4, NOD2 and NOD1 receptors are not essential to the innate immune response to infectio

Distribution and severity of placental lesions caused by the Chlamydia abortus 1B vaccine strain in vaccinated ewes

Chlamydia abortus infects livestock species worldwide and is the cause of enzootic abortion of ewes (EAE). In Europe, control of the disease is achieved using a live vaccine based on C. abortus 1B strain. Although the vaccine has been useful for controlling disease outbreaks, abortion events due to the vaccine have been reported. Recently, placental pathology resulting from a vaccine type strain (vt) infection has been reported and shown to be similar to that resulting from a natural wild-type (wt) infection. The aim of this study was to extend these observations by comparing the distribution and severity of the lesions, the composition of the predominating cell infiltrate, the amount of bacteria present and the role of the blood supply in infection. A novel system for grading the histological and pathological features present was developed and the resulting multi-parameter data were statistically transformed for exploration and visualisation through a tailored principal component analysis (PCA) to evaluate the difference between them. The analysis provided no evidence of meaningful differences between vt and wt strains in terms of the measured pathological parameters. The study also contributes a novel methodology for analysing the progression of infection in the placenta for other abortifacient pathogens.EEA MercedesFil: Caspe, Sergio Gaston. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mercedes; ArgentinaFil: Caspe, Sergio Gaston. Moredun Research Institute; Reino UnidoFil: Caspe, Sergio Gaston. University of Edinburgh. Royal (Dick) School of Veterinary Studies; Reino UnidoFil: Palarea-Albaladejo, Javier. Biomathematics & Statistics Scotland; Reino UnidoFil: Underwood, Clare. Moredun Research Institute; Reino UnidoFil: Livingstone, Morag. Moredun Research Institute; Reino UnidoFil: Wattegedera, Sean Ranjan. Moredun Research Institute; Reino UnidoFil: Milne, Elspeth. University of Edinburgh. Royal (Dick) School of Veterinary Studies; Reino UnidoFil: Sargison, Neil Donald. University of Edinburgh. Royal (Dick) School of Veterinary Studies; Reino UnidoFil: Chianini, Francesca. Moredun Research Institute; Reino UnidoFil: Longbottom, David. Moredun Research Institute; Reino Unid

The 1B vaccine strain of Chlamydia abortus produces placental pathology indistinguishable from a wild type infection

Chlamydia abortus is one of the most commonly diagnosed causes of infectious abortion in small ruminants worldwide. Control of the disease (Enzootic Abortion of Ewes or EAE) is achieved using the commercial live, attenuated C. abortus 1B vaccine strain, which can be distinguished from virulent wild-type (wt) strains by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. Published studies applying this typing method and whole-genome sequence analyses to cases of EAE in vaccinated and non-vaccinated animals have provided strong evidence that the 1B strain is not attenuated and can infect the placenta causing disease in some ewes. Therefore, the objective of this study was to characterise the lesions found in the placentas of ewes vaccinated with the 1B strain and to compare these to those resulting from a wt infection. A C. abortus-free flock of multiparous adult ewes was vaccinated twice, over three breeding seasons, each before mating, with the commercial C. abortus 1B vaccine strain (Cevac® Chlamydia, Ceva Animal Health Ltd.). In the second lambing season following vaccination, placentas (n = 117) were collected at parturition and analysed by C. abortus-specific real-time quantitative PCR (qPCR). Two placentas, from a single ewe, which gave birth to live twin lambs, were found to be positive by qPCR and viable organisms were recovered and identified as vaccine type (vt) by PCR-RFLP, with no evidence of any wt strain being present. All cotyledons from the vt-infected placentas were analysed by histopathology and immunohistochemistry and compared to those from wt-infected placentas. Both vt-infected placentas showed lesions typical of those found in a wt infection in terms of their severity, distribution, and associated intensity of antigen labelling. These results conclusively demonstrate that the 1B strain can infect the placenta, producing typical EAE placental lesions that are indistinguishable from those found in wt infected animals

Transcriptional analysis of in vitro expression patterns of chlamydophila abortus polymorphic outer membrane proteins during the chlamydial developmental cycle.

Chlamydophila abortus is the aetiological agent of ovine enzootic abortion. Sequencing, annotation and comparative analysis of the genome of C. abortus strain S26/3 has revealed variation in theloci encoding the polymorphic membrane proteins (Pmps). These Pmps resemble autotransporter proteins of the type V secretion system, suggesting an important role in chlamydial pathogenesis. The purpose of this study was to characterise the transcriptional expression patterns of this family during the developmental cycle of C. abortus. McCoy cells were infected with C. abortus and analysed for pmp mRNA expression over a 72 h period. Few pmp transcripts were detected in the early stages of the developmental cycle. Peakexpression occurred at 48 h post-infection (p.i.) other than for pmp5E, where it was observed at 24 h p.i. Overall, expression of pmps 5E, 18D and 10G were found to be 40 to 100-fold higher than the lowest expressing pmps (6H, 13G and 15G) at 24 h p.i., while pmps 18D and 17G were 14 to 16-fold higher than the lowest (11G, 14G and 15G) at 48 h. Levels of expression for all the other pmp genes were below one copy per genome at any time point. The expression of all the pmps reduced to near base-line levels by 60 hp.i. These results demonstrate that pmp expression in C. abortus is mid to late cycle, consistent with conversion of the reticulate body to the elementary body. The low level of pmp transcription may beindicative of heterogeneity in expression, suggesting a possible role for some of the Pmps in antigenic variation and chlamydial pathogenesis

Antibody responses to recombinant protein fragments of the major outer membrane protein and polymorphic outer membrane protein POMP90 in Chlamydophila abortus-infected pregnant sheep

Chlamydophila abortus is one of the major causes of infectious abortion in pregnant sheep (enzootic abortion of ewes or EAE) worldwide. Organisms shed in infected placentas and uterine discharges at lambing time are the main sources of environmental contamination, responsible for transmission to susceptible animals and possible human contacts. In the present study, a recently developed test, based on a recombinant fragment of the polymorphic outer membrane protein POMP90 (rOMP90-4 indirect enzyme-linked immunosorbent assay [iELISA]) and one based on the variable segment 2 (VS2) region of the major outer membrane protein (MOMP) (MOMP VS2 iELISA) were compared using sera from C. abortus-infected ewes at different stages throughout pregnancy. The rOMP90 iELISA detected antibody much earlier in pregnancy than the MOMP iELISA, which, like the complement fixation test, detected antibody only at the time of abortion or lambing. No anti-MOMP antibody response could be detected in three of seven experimentally infected ewes. Furthermore, the rOMP90 iELISA detected antibody in an animal that seroconverted during the course of the study, which the MOMP iELISA failed to detect. Overall, the results show that the rOMP90-4 iELISA is considerably more sensitive than the MOMP VS2 iELISA for identifying animals infected with C. abortus. Earlier detection of infection will allow appropriate control measures to be taken to reduce environmental contamination, thus limiting the spread of infection, financial losses, and the possible risks of zoonotic transmission to humans