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1.
Vaccines (Basel) ; 12(4)2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38675805

ABSTRACT

Chlamydia trachomatis (Ct) infections are the most common sexually transmitted infection (STI). Despite effective antibiotics for Ct, undetected infections or delayed treatment can lead to infertility, ectopic pregnancies, and chronic pelvic pain. Besides humans, chlamydia poses similar health challenges in animals such as C. suis (Cs) in pigs. Based on the similarities between humans and pigs, as well as their chlamydia species, we use pigs as a large biomedical animal model for chlamydia research. In this study, we used the pig model to develop a vaccine candidate against Ct. The vaccine candidate consists of TriAdj-adjuvanted chlamydial-protease-like activity factor (CPAF) protein. We tested two weekly administration options-twice intranasal (IN) followed by twice intramuscular (IM) and twice IM followed by twice IN. We assessed the humoral immune response in both serum using CPAF-specific IgG (including antibody avidity determination) and also in cervical and rectal swabs using CPAF-specific IgG and IgA ELISAs. The systemic T-cell response was analyzed following in vitro CPAF restimulation via IFN-γ and IL-17 ELISpots, as well as intracellular cytokine staining flow cytometry. Our data demonstrate that while the IN/IM vaccination mainly led to non-significant systemic immune responses, the vaccine candidate is highly immunogenic if administered IM/IN. This vaccination strategy induced high serum anti-CPAF IgG levels with strong avidity, as well as high IgA and IgG levels in vaginal and rectal swabs and in uterine horn flushes. In addition, this vaccination strategy prompted a pronounced cellular immune response. Besides inducing IL-17 production, the vaccine candidate induced a strong IFN-γ response with CD4 T cells. In IM/IN-vaccinated pigs, these cells also significantly downregulated their CCR7 expression, a sign of differentiation into peripheral-tissue-homing effector/memory cells. Conclusively, this study demonstrates the strong immunogenicity of the IM/IN-administered TriAdj-adjuvanted Ct CPAF vaccine candidate. Future studies will test the vaccine efficacy of this promising Ct vaccine candidate. In addition, this project demonstrates the suitability of the Cs pre-exposed outbred pig model for Ct vaccine development. Thereby, we aim to open the bottleneck of large animal models to facilitate the progression of Ct vaccine candidates into clinical trials.

2.
Front Microbiol ; 13: 977796, 2022.
Article in English | MEDLINE | ID: mdl-36212883

ABSTRACT

Although porcine reproductive and respiratory syndrome virus (PRRSV) vaccines have been available in North America for almost 30 years, many vaccines face a significant hurdle: they must provide cross-protection against the highly diverse PRRSV strains. This cross-protection, or heterologous vaccine efficacy, relies greatly on the vaccine's ability to induce a strong immune response against various strains-heterologous immunogenicity. Thus, this study investigated vaccine efficacy and immunogenicity of a modified live virus (MLV) against four heterologous type 2 PRRSV (PRRSV-2) strains. In this study, 60 pigs were divided into 10 groups. Half were MOCK-vaccinated, and the other half vaccinated with the Prevacent® PRRS MLV vaccine. Four weeks after vaccination, groups were challenged with either MOCK, or four PRRSV-2 strains from three different lineages-NC174 or NADC30 (both lineage 1), VR2332 (lineage 5), or NADC20 (lineage 8). Pre-and post-challenge, lung pathology, viral loads in both nasal swabs and sera, anti-PRRSV IgA/G, neutralizing antibodies, and the PRRSV-2 strain-specific T-cell response were evaluated. At necropsy, the lung samples were collected to assess viral loads, macroscopical and histopathological findings, and IgA levels in bronchoalveolar lavage. Lung lesions were only induced by NC174, NADC20, and NADC30; within these, vaccination resulted in lower gross and microscopic lung lesion scores of the NADC20 and NADC30 strains. All pigs became viremic and vaccinated pigs had decreased viremia upon challenge with NADC20, NADC30, and VR2332. Regarding vaccine immunogenicity, vaccination induced a strong systemic IgG response and boosted the post-challenge serum IgG levels for all strains. Furthermore, vaccination increased the number of animals with neutralizing antibodies against three of the four challenge strains-NADC20, NADC30, and VR2332. The heterologous T-cell response was also improved by vaccination: Not only did vaccination increase the induction of heterologous effector/memory CD4 T cells, but it also improved the heterologous CD4 and CD8 proliferative and/or IFN-γ response against all strains. Importantly, correlation analyses revealed that the (non-PRRSV strain-specific) serum IgG levels and the PRRSV strain-specific CD4 T-cell response were the best immune correlates of protection. Overall, the Prevacent elicited various degrees of efficacy and immunogenicity against four heterologous and phylogenetically distant strains of PRRSV-2.

3.
Front Vet Sci ; 9: 965316, 2022.
Article in English | MEDLINE | ID: mdl-36311661

ABSTRACT

Mice with severe combined immunodeficiency are commonly used as hosts of human cells. Size, longevity, and physiology, however, limit the extent to which immunodeficient mice can model human systems. To address these limitations, we generated RAG2 -/- IL2RG y/- immunodeficient pigs and demonstrate successful engraftment of SLA mismatched allogeneic D42 fetal liver cells, tagged with pH2B-eGFP, and human CD34+ hematopoietic stem cells after in utero cell transplantation. Following intrauterine injection at day 42-45 of gestation, fetuses were allowed to gestate to term and analyzed postnatally for the presence of pig (allogeneic) and human (xenogeneic) B cells, T-cells and NK cells in peripheral blood and other lymphoid tissues. Engraftment of allogeneic hematopoietic cells was detected based on co-expression of pH2B-eGFP and various markers of differentiation. Analysis of spleen revealed robust generation and engraftment of pH2B-eGFP mature B cells (and IgH recombination) and mature T-cells (and TCR-ß recombination), T helper (CD3+CD4+) and T cytotoxic (CD3+CD8+) cells. The thymus revealed engraftment of pH2B-eGFP double negative precursors (CD4-CD8-) as well as double positive (CD4+, CD8+) precursors and single positive T-cells. After intrauterine administration of human CD34+ hematopoietic stem cells, analysis of peripheral blood and lymphoid tissues revealed the presence of human T-cells (CD3+CD4+ and CD3+CD8+) but no detectable B cells or NK cells. The frequency of human CD45+ cells in the circulation decreased rapidly and were undetectable within 2 weeks of age. The frequency of human CD45+ cells in the spleen also decreased rapidly, becoming undetectable at 3 weeks. In contrast, human CD45+CD3+ T-cells comprised >70% of cells in the pig thymus at birth and persisted at the same frequency at 3 weeks. Most human CD3+ cells in the pig's thymus expressed CD4 or CD8, but few cells were double positive (CD4+ CD8+). In addition, human CD3+ cells in the pig thymus contained human T-cell excision circles (TREC), suggesting de novo development. Our data shows that the pig thymus provides a microenvironment conducive to engraftment, survival and development of human T-cells and provide evidence that the developing T-cell compartment can be populated to a significant extent by human cells in large animals.

4.
Indoor Air ; 32(1): e12938, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34693567

ABSTRACT

Self-contamination during doffing of personal protective equipment (PPE) is a concern for healthcare workers (HCW) following SARS-CoV-2-positive patient care. Staff may subconsciously become contaminated through improper glove removal; so, quantifying this exposure is critical for safe working procedures. HCW surface contact sequences on a respiratory ward were modeled using a discrete-time Markov chain for: IV-drip care, blood pressure monitoring, and doctors' rounds. Accretion of viral RNA on gloves during care was modeled using a stochastic recurrence relation. In the simulation, the HCW then doffed PPE and contaminated themselves in a fraction of cases based on increasing caseload. A parametric study was conducted to analyze the effect of: (1a) increasing patient numbers on the ward, (1b) the proportion of COVID-19 cases, (2) the length of a shift, and (3) the probability of touching contaminated PPE. The driving factors for the exposure were surface contamination and the number of surface contacts. The results simulate generally low viral exposures in most of the scenarios considered including on 100% COVID-19 positive wards, although this is where the highest self-inoculated dose is likely to occur with median 0.0305 viruses (95% CI =0-0.6 viruses). Dose correlates highly with surface contamination showing that this can be a determining factor for the exposure. The infection risk resulting from the exposure is challenging to estimate, as it will be influenced by the factors such as virus variant and vaccination rates.


Subject(s)
Air Pollution, Indoor , COVID-19 , Fomites , Occupational Exposure , Personal Protective Equipment , Fomites/virology , Gloves, Protective/virology , Hospitals , Humans , Personal Protective Equipment/virology , SARS-CoV-2
5.
Indoor Air ; 31(5): 1657-1672, 2021 09.
Article in English | MEDLINE | ID: mdl-33913202

ABSTRACT

Healthcare professionals (HCPs) are exposed to highly infectious viruses, such as norovirus, through multiple exposure routes. Understanding exposure mechanisms will inform exposure mitigation interventions. The study objective was to evaluate the influences of hospital patient room layout on differences in HCPs' predicted hand contamination from deposited norovirus particles. Computational fluid dynamic (CFD) simulations of a hospital patient room were investigated to find differences in spatial deposition patterns of bioaerosols for right-facing and left-facing bed layouts under different ventilation conditions. A microbial transfer model underpinned by observed mock care for three care types (intravenous therapy (IV) care, observational care, and doctors' rounds) was applied to estimate HCP hand contamination. Viral accruement was contrasted between room orientation, care type, and by assumptions about whether bioaerosol deposition was the same or variable by room orientation. Differences in sequences of surface contacts were observed for care type and room orientation. Simulated viral accruement differences between room types were influenced by mostly by differences in bioaerosol deposition and by behavior sequences when deposition patterns for the room orientations were similar. Differences between care types were likely driven by differences in hand-to-patient contact frequency, with doctors' rounds resulting in the greatest predicted viral accruement on hands.


Subject(s)
Air Pollution, Indoor , Patients' Rooms , Ventilation , Cross Infection , Delivery of Health Care , Hand , Health Personnel , Hospitals , Humans
6.
J Psychiatr Ment Health Nurs ; 28(4): 670-681, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33202081

ABSTRACT

WHAT IS KNOWN ON THE SUBJECT?: Internationally, stigma towards people with mental illness has reduced due to greater understanding, education and advocacy in the community, and more focus on recovery-oriented care within practice guidelines. However, many people with a diagnosis of BPD continue to experience stigma and difficulty accessing health services. Contributing factors include lack of understanding of BPD and effective management by health professionals, stigma from the general population and within healthcare services, and financial and geographical barriers. Mental health nurses comprise a large part of the healthcare workforce responsible for the day-to-day care of people diagnosed with BPD. WHAT THE PAPER ADDS TO EXISTING KNOWLEDGE: This paper investigates how Australian consumer perspectives on BPD management have changed over time. Comments from a large survey, delivered to consumers in 2011 (N = 153) and 2017 (N = 424), were analysed for common themes. Themes were broadly related to NHMRC BPD Guidelines sections released in 2013. These data sets therefore present an opportunity to evaluate changes in consumer perspectives pre- and post-Guideline release. Although no direct causal relationship can be drawn, analysing these changes can potentially assist with understanding the impact of the Guidelines in practice. No such analysis of the Australian Guidelines has been conducted to date in the existing literature. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: Many people diagnosed with BPD continue to experience stigma, barriers to treatment and difficulty accessing appropriate services. Widespread practical implementation of the Guidelines was not apparent; however, improved general awareness and understanding of BPD from consumers and health professionals were evident. Improved education and practice across each and all aspects of the Guidelines are indicated. The Guidelines need review to ensure they are in-line with current evidence-based practice, as well as effective health professional education, support and funding to embed the revised Guidelines into practice. ABSTRACT: Introduction Internationally, many individuals diagnosed with BPD continue to experience stigma within health care and are more likely to be viewed as manipulative and evoke negative responses from clinicians, compared with other mental health consumers. Aim/Question To understand Australian consumer perspectives regarding BPD management, and how these have changed between 2011 and 2017. To comment on how NHMRC BPD Guidelines, released 2013, are faring in practice. Method Individuals who identified a BPD diagnosis completed a 75-question survey, delivered online Australia-wide, in 2011 (N = 153) and 2017 (N = 424), providing comparative data sets to evaluate changes in consumer perspective on BPD management. Results Many people diagnosed with BPD experience difficulties when seeking help, stigma within health services and barriers to treatment. Improved general awareness, communication and understanding of BPD from consumers and health professionals were evident. Discussion Consumers demonstrated increased BPD-literacy and help-seeking behaviours in 2017, providing opportunity for health professionals to build stronger therapeutic relationships. Widespread practical implementation of the Guidelines does not appear to have been achieved. More health professional education, updated Guidelines, funding and strategies to embed these Guidelines into practice are needed. Implications for Practice Mental health nurses regularly provide care to people diagnosed with BPD; with practical education and support, they and other health professionals can improve their confidence in practice and provide better quality care to consumers.


Subject(s)
Borderline Personality Disorder , Australia , Health Facilities , Humans , Mental Health , Social Stigma
7.
Plant J ; 101(6): 1349-1367, 2020 03.
Article in English | MEDLINE | ID: mdl-31680354

ABSTRACT

It has been hypothesised that vegetative desiccation tolerance in resurrection plants evolved via reactivation of the canonical LAFL (i.e. LEC1, ABI3, FUS3 and LEC2) transcription factor (TF) network that activates the expression of genes during the maturation of orthodox seeds leading to desiccation tolerance of the plant embryo in most angiosperms. There is little direct evidence to support this, however, and the transcriptional changes that occur during seed maturation in resurrection plants have not previously been studied. Here we performed de novo transcriptome assembly for Xerophyta humilis, and analysed gene expression during seed maturation and vegetative desiccation. Our results indicate that differential expression of a set of 4205 genes is common to maturing seeds and desiccating leaves. This shared set of genes is enriched for gene ontology terms related to abiotic stress, including water stress and abscisic acid signalling, and includes many genes that are seed-specific in Arabidopsis thaliana and targets of ABI3. However, while we observed upregulation of orthologues of the canonical LAFL TFs and ABI5 during seed maturation, similar to what is seen in A. thaliana, this did not occur during desiccation of leaf tissue. Thus, reactivation of components of the seed desiccation program in X. humilis vegetative tissues likely involves alternative transcriptional regulators.


Subject(s)
Pandanaceae/physiology , Seeds/metabolism , Dehydration , Gene Expression Regulation, Plant/physiology , Pandanaceae/metabolism , Plant Proteins/metabolism , Plant Proteins/physiology , Seeds/growth & development , Seeds/physiology , Transcription Factors/metabolism , Transcription Factors/physiology
8.
J Transl Med ; 15(1): 15, 2017 01 18.
Article in English | MEDLINE | ID: mdl-28100276

ABSTRACT

BACKGROUND: Stratified or personalised medicine targets treatments for groups of individuals with a disorder based on individual heterogeneity and shared factors that influence the likelihood of response. Psychiatry has traditionally defined diagnoses by constellations of co-occurring signs and symptoms that are assigned a categorical label (e.g. schizophrenia). Trial methodology in psychiatry has evaluated interventions targeted at these categorical entities, with diagnoses being equated to disorders. Recent insights into both the nosology and neurobiology of psychiatric disorder reveal that traditional categorical diagnoses cannot be equated with disorders. We argue that current quantitative methodology (1) inherits these categorical assumptions, (2) allows only for the discovery of average treatment response, (3) relies on composite outcome measures and (4) sacrifices valuable predictive information for stratified and personalised treatment in psychiatry. METHODS AND FINDINGS: To achieve a truly 'stratified psychiatry' we propose and then operationalise two necessary steps: first, a formal multi-dimensional representation of disorder definition and clinical state, and second, the similar redefinition of outcomes as multidimensional constructs that can expose within- and between-patient differences in response. We use the categorical diagnosis of schizophrenia-conceptualised as a label for heterogeneous disorders-as a means of introducing operational definitions of stratified psychiatry using principles from multivariate analysis. We demonstrate this framework by application to the Clinical Antipsychotic Trials of Intervention Effectiveness dataset, showing heterogeneity in both patient clinical states and their trajectories after treatment that are lost in the traditional categorical approach with composite outcomes. We then systematically review a decade of registered clinical trials for cognitive deficits in schizophrenia highlighting existing assumptions of categorical diagnoses and aggregate outcomes while identifying a small number of trials that could be reanalysed using our proposal. CONCLUSION: We describe quantitative methods for the development of a multi-dimensional model of clinical state, disorders and trajectories which practically realises stratified psychiatry. We highlight the potential for recovering existing trial data, the implications for stratified psychiatry in trial design and clinical treatment and finally, describe different kinds of probabilistic reasoning tools necessary to implement stratification.


Subject(s)
Mental Disorders/therapy , Precision Medicine , Psychiatry , Cognition , Humans , Multivariate Analysis , Schizophrenia/diagnosis , Schizophrenia/therapy
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