Provider Perspectives on an Integrated Behavioral Health Prevention Approach in Pediatric Primary Care.

The purpose of this study was to use qualitative interviews to ascertain the perspective of pediatric primary care providers on the implementation of Integrated Behavioral Health (IBH) as provided by psychologists within an expanded HealthySteps™ model, and with a particular focus on prevention of behavioral health symptoms in the first five years. A semi-structured interview guide was used to assess medical providers' perceptions of behavioral health integration into their primary care clinics. A conventional qualitative content analysis approach was utilized to identify patterns of meaning across qualitative interviews. Four themes were identified: (1) practice prior to IBH and initial concerns about integration, (2) psychologist's role and perceived added value, (3) what integration looks like in practice, and (4) perceived families' response to and experiences with IBH. Despite initial concerns about potential disruptions to clinic flow, providers indicated that adoption of IBH was seamless. The distinct roles of the psychologist were clear, and both treatment and prevention services provided by IBH were valued. Multidisciplinary collaboration and real-time response to family needs was seen as especially important and primary care providers reported that families were accepting of and highly valued IBH.

Inferred Causal Mechanisms of Persistent FMDV Infection in Cattle from Differential Gene Expression in the Nasopharyngeal Mucosa.

Foot-and-mouth disease virus (FMDV) can persistently infect pharyngeal epithelia in ruminants but not in pigs. Our previous studies demonstrated that persistent FMDV infection in cattle was associated with under-expression of several chemokines that recruit immune cells. This report focuses on the analysis of differentially expressed genes (DEG) identified during the transitional phase of infection, defined as the period when animals diverge between becoming carriers or terminators. During this phase, Th17-stimulating cytokines (IL6 and IL23A) and Th17-recruiting chemokines (CCL14 and CCL20) were upregulated in animals that were still infected (transitional carriers) compared to those that had recently cleared infection (terminators), whereas chemokines recruiting neutrophils and CD8+ T effector cells (CCL3 and ELR+CXCLs) were downregulated. Upregulated Th17-specific receptor, CCR6, and Th17-associated genes, CD146, MIR155, and ThPOK, suggested increased Th17 cell activity in transitional carriers. However, a complex interplay of the Th17 regulatory axis was indicated by non-significant upregulation of IL17A and downregulation of IL17F, two hallmarks of TH17 activity. Other DEG suggested that transitional carriers had upregulated aryl hydrocarbon receptor (AHR), non-canonical NFκB signaling, and downregulated canonical NFκB signaling. The results described herein provide novel insights into the mechanisms of establishment of FMDV persistence. Additionally, the fact that ruminants, unlike pigs, produce a large amount of AHR ligands suggests a plausible explanation of why FMDV persists in ruminants, but not in pigs.

Oxybenzone contamination from sunscreen pollution and its ecological threat to Hanauma Bay, Oahu, Hawaii, U.S.A.

Hanauma Bay is a 101-acre bay created by the partial collapse of a volcanic cone and once supported a vibrant coral reef system. It is the most popular swimming area in the Hawaiian Islands and has been reported to have averaged between 2.8 and 3.5 million visitors a year between the 1980s and the 2010s, with visitors averaging between 3000-4000 a day and peaking around 10,000-13,000 per day. Concentrations of oxybenzone and other common UV filters were measured in subsurface water samples and in sands from the beach-shower areas in Hanauma Bay. Results demonstrate that beach showers also can be a source of sunscreen environmental contamination. Hydrodynamic modeling indicates that oxybenzone contamination within Hanauma Bay's waters could be retained between 14 and 50 h from a single release event period. Focusing on only oxybenzone, two different Hazard and Risk Assessment analyses were conducted to determine the danger of oxybenzone to Hanauma Bay's coral reef system. Results indicate that oxybenzone contamination poses a significant threat to the wildlife of Hanauma Bay. To recover Hanauma Bay's natural resources to a healthy condition and to satisfactorily conserve its coral reef and sea grass habitats, effective tourism management policies need to be implemented that mitigate the threat of sunscreen pollution.

Using a pragmatically adapted, low-cost contingency management intervention to promote heroin abstinence in individuals undergoing treatment for heroin use disorder in UK drug services (PRAISE): a cluster randomised trial.

INTRODUCTION: Most individuals treated for heroin use disorder receive opioid agonist treatment (OAT)(methadone or buprenorphine). However, OAT is associated with high attrition and persistent, occasional heroin use. There is some evidence for the effectiveness of contingency management (CM), a behavioural intervention involving modest financial incentives, in encouraging drug abstinence when applied adjunctively with OAT. UK drug services have a minimal track record of applying CM and limited resources to implement it. We assessed a CM intervention pragmatically adapted for ease of implementation in UK drug services to promote heroin abstinence among individuals receiving OAT. DESIGN: Cluster randomised controlled trial. SETTING AND PARTICIPANTS: 552 adults with heroin use disorder (target 660) enrolled from 34 clusters (drug treatment clinics) in England between November 2012 and October 2015. INTERVENTIONS: Clusters were randomly allocated 1:1:1 to OAT plus 12× weekly appointments with: (1) CM targeted at opiate abstinence at appointments (CM Abstinence); (2) CM targeted at on-time attendance at appointments (CM Attendance); or (3) no CM (treatment as usual; TAU). Modifications included monitoring behaviour weekly and fixed incentives schedule. MEASUREMENTS: Primary outcome: heroin abstinence measured by heroin-free urines (weeks 9-12). SECONDARY OUTCOMES: heroin abstinence 12 weeks after discontinuation of CM (weeks 21-24); attendance; self-reported drug use, physical and mental health. RESULTS: CM Attendance was superior to TAU in encouraging heroin abstinence. Odds of a heroin-negative urine in weeks 9-12 was statistically significantly greater in CM Attendance compared with TAU (OR=2.1; 95% CI 1.1 to 3.9; p=0.030). CM Abstinence was not superior to TAU (OR=1.6; 95% CI 0.9 to 3.0; p=0.146) or CM Attendance (OR=1.3; 95% CI 0.7 to 2.4; p=0.438) (not statistically significant differences). Reductions in heroin use were not sustained at 21-24 weeks. No differences between groups in self-reported heroin use. CONCLUSIONS: A pragmatically adapted CM intervention for routine use in UK drug services was moderately effective in encouraging heroin abstinence compared with no CM only when targeted at attendance. CM targeted at abstinence was not effective. TRIAL REGISTRATION NUMBER: ISRCTN 01591254.

Using Large-Scale Additive Manufacturing as a Bridge Manufacturing Process in Response to Shortages in Personal Protective Equipment during the COVID-19 Outbreak.

The global coronavirus disease (COVID)-19 pandemic has led to an international shortage of personal protective equipment (PPE), with traditional supply chains unable to cope with the significant demand leading to critical shortfalls. A number of open and crowdsourcing initiatives have sought to address this shortfall by producing equipment such as protective face shields using additive manufacturing techniques such as fused filament fabrication (FFF). This paper reports the process of designing and manufacturing protective face shields using large-scale additive manufacturing (LSAM) to produce the major thermoplastic components of the face shield. LSAM offers significant advantages over other additive manufacturing technologies in bridge manufacturing scenarios as a true transition between prototypes and mass production techniques such as injection molding. In the context of production of COVID-19 face shields, the ability to produce the optimized components in under 5 min compared to what would typically take 1 - 2 h using another additive manufacturing technologies meant that significant production volume could be achieved rapidly with minimal staffing.

Mechanisms of Maintenance of Foot-and-Mouth Disease Virus Persistence Inferred From Genes Differentially Expressed in Nasopharyngeal Epithelia of Virus Carriers and Non-carriers.

Foot-and-mouth disease virus (FMDV) causes persistent infection of nasopharyngeal epithelial cells in ~50% of infected ruminants. The mechanisms involved are not clear. This study provides a continued investigation of differentially expressed genes (DEG) identified in a previously published transcriptomic study analyzing micro-dissected epithelial samples from FMDV carriers and non-carriers. Pathway analysis of DEG indicated that immune cell trafficking, cell death and hematological system could be affected by the differential gene expression. Further examination of the DEG identified five downregulated (chemerin, CCL23, CXCL15, CXCL16, and CXCL17) and one upregulated (CCL2) chemokines in carriers compared to non-carriers. The differential expression could reduce the recruitment of neutrophils, antigen-experienced T cells and dendritic cells and increase the migration of macrophages and NK cells to the epithelia in carriers, which was supported by DEG expressed in these immune cells. Downregulated chemokine expression could be mainly due to the inhibition of canonical NFκB signaling based on DEG in the signaling pathways and transcription factor binding sites predicted from the proximal promoters. Additionally, upregulated CD69, IL33, and NID1 and downregulated CASP3, IL17RA, NCR3LG1, TP53BP1, TRAF3, and TRAF6 in carriers could inhibit the Th17 response, NK cell cytotoxicity and apoptosis. Based on our findings, we hypothesize that (1) under-expression of chemokines that recruit neutrophils, antigen-experienced T cells and dendritic cells, (2) blocking NK cell binding to target cells and (3) suppression of apoptosis induced by death receptor signaling, viral RNA, and cell-mediated cytotoxicity in the epithelia compromised virus clearance and allowed FMDV to persist. These hypothesized mechanisms provide novel information for further investigation of persistent FMDV infection.

A Single Amino Acid Substitution in the Matrix Protein (M51R) of Vesicular Stomatitis New Jersey Virus Impairs Replication in Cultured Porcine Macrophages and Results in Significant Attenuation in Pigs.

In this study, we explore the virulence of vesicular stomatitis New Jersey virus (VSNJV) in pigs and its potential relationship with the virus's ability to modulate innate responses. For this purpose, we developed a mutant of the highly virulent strain NJ0612NME6, containing a single amino acid substitution in the matrix protein (M51R). The M51R mutant of NJ0612NME6 was unable to suppress the transcription of genes associated with the innate immune response both in primary fetal porcine kidney cells and porcine primary macrophage cultures. Impaired viral growth was observed only in porcine macrophage cultures, indicating that the M51 residue is required for efficient replication of VSNJV in these cells. Furthermore, when inoculated in pigs by intradermal scarification of the snout, M51R infection was characterized by decreased clinical signs including reduced fever and development of less and smaller secondary vesicular lesions. Pigs infected with M51R had decreased levels of viral shedding and absence of RNAemia compared to the parental virus. The ability of the mutant virus to infect pigs by direct contact remained intact, indicating that the M51R mutation resulted in a partially attenuated phenotype capable of causing primary lesions and transmitting to sentinel pigs. Collectively, our results show a positive correlation between the ability of VSNJV to counteract the innate immune response in swine macrophage cultures and the level of virulence in pigs, a natural host of this virus. More studies are encouraged to evaluate the interaction of VSNJV with macrophages and other components of the immune response in pigs.

Citizen Science: A New Approach to Smoke-Free Policy Advocacy.

Kentucky has the second highest adult smoking rate, has the highest incidence of lung cancer in the nation, and does not have a state law prohibiting smoking inside workplaces. These tobacco disparities and policy gap leave Kentucky behind tobacco control progress made in other areas of the United States. Williamstown is a rural community with a population of 3,900 and a strong history of tobacco use. In 2017, the Northern Kentucky Health Department, in partnership with Interact for Health, worked with two coalitions to collect data, educate the community, and advocate for a local smoke-free policy. Coalition members collected 227 public opinion surveys. Community leaders-including the mayor-and advocates participated in Citizen Science, a research collaboration between scientists and volunteers. Advocates were trained on AirBeam monitors, wearable devices that gather air quality data in real time, and then were deployed in six establishments. The indoor air quality in smoking establishments was two times worse than the outdoor air quality standard. Community leaders and advocates then mobilized to educate City Council members on the benefits of a smoke-free policy, focusing on business, health, and tourism. In 2018, the Williamstown City Council voted in favor of the smoke-free policy, becoming the first jurisdiction in the Northern Kentucky region with a comprehensive smoke-free policy. The Citizen Science process helped develop coalition capacity, build community support, and engage policymakers in a successful smoke-free policy effort. Through participatory and inclusive efforts, local residents were able to affect policy change in the direction of health for all people.

Non-Invasive Transcranial Nano-Pulsed Laser Therapy Ameliorates Cognitive Function and Prevents Aberrant Migration of Neural Progenitor Cells in the Hippocampus of Rats Subjected to Traumatic Brain Injury.

Traumatic brain injury (TBI) can lead to chronic diseases, including neurodegenerative disorders and epilepsy. The hippocampus, one of the most affected brain region after TBI, plays a critical role in learning and memory and is one of the only two regions in the brain in which new neurons are generated throughout life from neural stem cells (NSC) in the dentate gyrus (DG). These cells migrate into the granular layer where they integrate into the hippocampus circuitry. While increased proliferation of NSC in the hippocampus is known to occur shortly after injury, reduced neuronal maturation and aberrant migration of progenitor cells in the hilus contribute to cognitive and neurological dysfunctions, including epilepsy. Here, we tested the ability of a novel, proprietary non-invasive nano-pulsed laser therapy (NPLT), that combines near-infrared laser light (808 nm) and laser-generated, low-energy optoacoustic waves, to mitigate TBI-driven impairments in neurogenesis and cognitive function in the rat fluid percussion injury model. We show that injured rats treated with NPLT performed significantly better in a hippocampus-dependent cognitive test than did sham rats. In the DG, NPLT significantly decreased TBI-dependent impaired maturation and aberrant migration of neural progenitors, while preventing TBI-induced upregulation of specific microRNAs (miRNAs) in NSC. NPLT did not significantly reduce TBI-induced microglia activation in the hippocampus. Our data strongly suggest that NPLT has the potential to be an effective therapeutic tool for the treatment of TBI-induced cognitive dysfunction and dysregulation of neurogenesis, and point to modulation of miRNAs as a possible mechanism mediating its neuroprotective effects.

Mechanisms of African swine fever virus pathogenesis and immune evasion inferred from gene expression changes in infected swine macrophages.

African swine fever (ASF) is a swine disease caused by a large, structurally complex, double-stranded DNA virus, African swine fever virus (ASFV). In domestic pigs, acute infection by highly virulent ASF viruses causes hemorrhagic fever and death. Previous work has suggested that ASFV pathogenesis is primarily mediated by host cytokines produced by infected monocytes and macrophages. To better understand molecular mechanisms mediating virus pathogenesis and immune evasion, we used transcriptome analysis to identify gene expression changes after ASFV infection in ex vivo swine macrophages. Our results suggest that the cytokines of TNF family including FASLG, LTA, LTB, TNF, TNFSF4, TNFSF10, TNFSF13B and TNFSF18 are the major causative cytokine factors in ASF pathogenesis via inducing apoptosis. Other up-regulated proinflammatory cytokines (IL17F and interferons) and down-regulated anti-inflammatory cytokine (IL10) may also significantly contribute to ASF pathogenesis and cause excessive tissue inflammatory responses. The differential expression of genes also indicates that ASFV could evade both the innate and adaptive immune responses by (i) inhibiting MHC Class II antigen processing and presentation, (ii) avoiding CD8+ T effector cells and neutrophil extracellular traps via decreasing expression of neutrophil/CD8+ T effector cell-recruiting chemokines, (iii) suppressing M1 activation of macrophages, (iv) inducing immune suppressive cytokines, and (v) inhibiting the processes of macrophage autophagy and apoptosis. These results provide novel information to further investigate and better understand the mechanism of pathogenesis and immune evasion of this devastating swine disease.

Hippocampal stem cells promotes synaptic resistance to the dysfunctional impact of amyloid beta oligomers via secreted exosomes.

BACKGROUND: Adult hippocampal neurogenesis plays an important role in synaptic plasticity and cogntive function. We reported that higher numbers of neural stem cells (NSC) in the hippocampus of cognitively-intact individuals with high Alzheimer's disease (AD) pathology (plaques and tangles) is associated with decreased synaptic amyloid beta oligomers (Aßο), an event linked to onset of dementia in AD. While these findings suggest a link between NSC and synaptic resistance to Aßο, the involved mechanism remains to be determined. With this goal in mind, here we investigated the ability of exosomes secreted from hippocampal NSC to promote synaptic resilience to Aßo. METHODS: Exosomes isolated from media of hippocampus NSC (NSC-exo) or mature hippocampal neuronal (MN-exo) cultures were delivered intracerebroventricularly (ICV) to mice before assessment of Aßο-induced suppression of hippocampal long-term potentiation (LTP) and memory deficits. Aßο binding to synapses was assessed in cultured hippocampal neurons and on synaptosomes isolated from hippocampal slices from wild type mice and from an inducible mouse model of NSC ablation (Nestin-δ-HSV-TK mice) treated with exosomes. Expression of CaMKII and of AMPA and NMDA glutamate receptor subunits in synaptosomes was measured by western blot. Small RNA Deep sequencing was performed to identify microRNAs enriched in NSC-exo as compared to MN-exo. Mimics of select miRNAs were injected ICV. RESULTS: NSC-exo, but not MN-exo, abolished Aßo-induced suppression of LTP and subsequent memory deficits. Furthermore, in hippocampal slices and cultured neurons, NSC-exo significantly decreased Aßo binding to the synapse. Similarly, transgenic ablation of endogenous NSC increased synaptic Aßo binding, which was reversed by exogenous NSC-exo. Phosphorylation of synaptic CaMKII was increased by NSC-exo, while AMPA and NMDA receptors were not affected. Lastly, we identified a set of miRNAs enriched in NSC-exo that, when injected ICV, protected the synapses from Aßo-binding and Aßo-induced LTP inhibition. CONCLUSIONS: These results identify a novel mechanism linking NSC-exo and synaptic susceptibility to Aßo that may underscore cognitive resilience of certain individuals with increased neurogenesis in spite of AD neuropathology and unmask a novel target for the development of a new treatment concept for AD centered on promoting synaptic resilience to toxic amyloid proteins.

Design and fabrication of 3-D printed conductive polymer structures for THz polarization control.

In this paper, we numerically and experimentally demonstrate the inverse polarization effect in three-dimensional (3-D) printed polarizers for the frequency range of 0.5 - 2.7 THz. The polarizers simply consist of 3-D printed strip lines of conductive polylactic acid (CPLA, Proto-Pasta) and do not require a substrate or any further metallic deposition. The experimental and numerical results show that the proposed structure acts as a broadband polarizer between the range of 0.3 THz to 2.7 THz, in which the inverse polarization effect is clearly seen for frequencies above 0.5 THz. In the inverse polarization effect, the transmission of the transverse electric (TE) component exceeds that of the TM component, in contrast to the behavior of a typical wire-grid polarizer. We show how the performance of the polarizers depends on the spacing and thickness of the CPLA structure; extinction ratios higher than 20 dB are achieved. This is the first report using CPLA to fabricate THz polarizers, demonstrating the potential of using conductive polymers to design THz components efficiently and robustly.

Experience of Family Physicians in Practice Transformation Networks.

To help health care practices transition away from fee-for-service reimbursement and toward value-based payment, the Transforming Clinical Practice Initiative was launched in October 2015. It was designed to provide clinicians support through peer-based Practice Transformation Networks (PTNs). A group of American Board of Family Medicine board-certified family physicians enrolled in PTNs described their expectations of and experiences with PTN participation; we analyzed open-text comments. Physicians expected and experienced PTN support in informatics and data, team building, and workflow and care coordination; however, expectations regarding patient care and engagement, costs and payment reform, and population and panel health were described less frequently.

Practice Rurality of Family Physicians Enrolled in a Practice Transformation Network.

The Transforming Clinical Practice Initiative prioritized the delivery of free practice transformation assistance by Practice Transformation Networks (PTNs) to small and rural practices that may otherwise lack the resources needed to succeed in Medicare's value-based payment (VBP) programs. We assessed the enrollment of rural practices in PTNs using 2016 TCPI enrollment data and American Board of Family Medicine recertification examination registration data from 2013 to 2016. PTNs enrolled a higher proportion of rural family medicine practices than are represented across the general workforce (P < .0001). We await more comprehensive data releases to fully understand enrollment to this important initiative.

Integrating Family as a Discipline by Providing Parent Led Curricula: Impact on LEND Trainees' Leadership Competency.

Background While the MCH Leadership Competencies and family as a discipline have been required elements of Leadership Education in Neurodevelopmental and related Disabilities (LEND) programs for over a decade, little research has been published on the efficacy of either programmatic component in the development of the next generation of leaders who can advocate and care for Maternal and Child Health (MCH) populations. Objective To test the effectiveness of integrating the family discipline through implementation of parent led curricula on trainees' content knowledge, skills, and leadership development in family-centered care, according to the MCH Leadership Competencies. Methods One hundred and two long-term (≥ 300 h) LEND trainees completed a clinical and leadership training program which featured intensive parent led curricula supported by a full-time family faculty member. Trainees rated themselves on the five Basic and Advanced skill items that comprise MCH Leadership Competency 8: Family-centered Care at the beginning and conclusion of their LEND traineeship. Results When compared to their initial scores, trainees rated themselves significantly higher across all family-centered leadership competency items at the completion of their LEND traineeship. Conclusions The intentional engagement of a full-time family faculty member and parent led curricula that include didactic and experiential components are associated with greater identification and adoption by trainees of family-centered attitudes, skills, and practices. However, the use of the MCH Leadership Competencies as a quantifiable measure of program evaluation, particularly leadership development, is limited.

Long-term pediatrician outcomes of a parent led curriculum in developmental disabilities.

Previous research has demonstrated high satisfaction and perceived relevance of Project DOCC (Delivery of Chronic Care), a parent led curriculum in developmental disabilities, across a sample of medical residents. AIMS: The influence of such a training program on the clinical practices and professional activities of these residents once they are established in their careers as physicians, however, has not been studied; this was the aim of the present study. METHODS: An anonymous follow-up survey was designed and disseminated to physicians who participated in Project DOCC during their one-month developmental disabilities rotation as part of their pediatrics or medicine/pediatric residency between 2002 and 2010. Fifty-eight physicians completed the survey. RESULTS: The findings suggest that participation in a parent led curriculum during medical residency had a lasting impact on physicians' relationships with families. Specifically, a majority of the physicians espoused a family-centered approach to care, a sensitivity to the interactional effect that caring for a Child with Special Health Care Needs (CSHCN) has on family members, the need for physicians to have a prominent role in community resource coordination, and the importance of an integrated approach to health care provision. CONCLUSIONS: Use of a parent led curriculum as a means to increase the provision of family-centered care by physicians is supported.

Evaluation of Infectivity, Virulence and Transmission of FDMV Field Strains of Serotypes O and A Isolated In 2010 from Outbreaks in the Republic of Korea.

Since the early 2000s outbreaks of foot-and-mouth disease (FMD) have been described in several previously FMD-free Asian nations, including the Republic of Korea (South Korea). One outbreak with FMD virus (FDMV) serotype A and two with serotype O occurred in South Korea in 2010/2011. The causative viruses belonged to lineages that had been spreading in South East Asia, far East and East Asia since 2009 and presented a great threat to the countries in that region. Most FMDV strains infect ruminants and pigs, as it happened during the outbreaks of FMDV serotype O in South Korea. Contrastingly, the strain of serotype A affected only ruminants. Based upon these findings, the intention of the work described in the current report was to characterize and compare the infectivity, virulence and transmission of both strains under laboratory conditions in cattle and pigs, by direct inoculation and contact exposure. As expected, FMDV serotype O was highly virulent in both cattle and swine by contact exposure and direct inoculation. Surprisingly, FMDV serotype A was highly virulent in swine, but was less infectious in cattle by contact exposure to infected swine or cattle. Interestingly, similar quantities of aerosolized FMDV RNA were detected during experiments with viruses of serotypes O and A. Specific virus-host interaction of A/SKR/2010 could affect the transmission of this strain to cattle, and this may explain in part the limited spread of the serotype A epizootic.

A colorimetric bioassay for high-throughput and cost-effectively assessing anti-foot-and-mouth disease virus activity.

Foot-and-mouth disease virus (FMDV) is one of the most contagious animal viruses. This virus is very sensitive to inhibition by type I interferons. Currently, a bioassay based on plaque reduction is used to measure anti-FMDV activity of porcine IFNs. The plaque reduction assay is tedious and difficult to utilize for high-throughput analysis. Using available FMDV susceptible bovine and porcine cells, we developed and tested a colorimetric assay based on cytopathic effect reduction for its ability to quantify FMDV-specific antiviral activity of bovine and porcine type I interferons. Our results show that this new method has significant advantages over other assays in terms of labor intensity, cost, high-throughput capability and/or anti-FMDV specific activity because of simpler procedures and direct measurement of antiviral activity. Several assay conditions were tested to optimize the procedures. The test results show that the assay can be standardized with fixed conditions and a standard or a reference for measuring antiviral activity as units. This is an excellent assay in terms of sensitivity and accuracy based on a statistical evaluation. The results obtained with this assay were highly correlated with a conventional virus titration method.

Phenotypic, ultra-structural, and functional characterization of bovine peripheral blood dendritic cell subsets.

Dendritic cells (DC) are multi-functional cells that bridge the gap between innate and adaptive immune systems. In bovine, significant information is lacking on the precise identity and role of peripheral blood DC subsets. In this study, we identify and characterize bovine peripheral blood DC subsets directly ex vivo, without further in vitro manipulation. Multi-color flow cytometric analysis revealed that three DC subsets could be identified. Bovine plasmacytoid DC were phenotypically identified by a unique pattern of cell surface protein expression including CD4, exhibited an extensive endoplasmic reticulum and Golgi apparatus, efficiently internalized and degraded exogenous antigen, and were the only peripheral blood cells specialized in the production of type I IFN following activation with Toll-like receptor (TLR) agonists. Conventional DC were identified by expression of a different pattern of cell surface proteins including CD11c, MHC class II, and CD80, among others, the display of extensive dendritic protrusions on their plasma membrane, expression of very high levels of MHC class II and co-stimulatory molecules, efficient internalization and degradation of exogenous antigen, and ready production of detectable levels of TNF-alpha in response to TLR activation. Our investigations also revealed a third novel DC subset that may be a precursor of conventional DC that were MHC class II+ and CD11c-. These cells exhibited a smooth plasma membrane with a rounded nucleus, produced TNF-alpha in response to TLR-activation (albeit lower than CD11c+ DC), and were the least efficient in internalization/degradation of exogenous antigen. These studies define three bovine blood DC subsets with distinct phenotypic and functional characteristics which can be analyzed during immune responses to pathogens and vaccinations of cattle.