METTL3 drives telomere targeting of TERRA lncRNA through m6A-dependent R-loop formation: a therapeutic target for ALT-positive neuroblastoma.

Telomerase-negative tumors maintain telomere length by alternative lengthening of telomeres (ALT), but the underlying mechanism behind ALT remains poorly understood. A proportion of aggressive neuroblastoma (NB), particularly relapsed tumors, are positive for ALT (ALT+), suggesting that a better dissection of the ALT mechanism could lead to novel therapeutic opportunities. TERRA, a long non-coding RNA (lncRNA) derived from telomere ends, localizes to telomeres in a R-loop-dependent manner and plays a crucial role in telomere maintenance. Here we present evidence that RNA modification at the N6 position of internal adenosine (m6A) in TERRA by the methyltransferase METTL3 is essential for telomere maintenance in ALT+ cells, and the loss of TERRA m6A/METTL3 results in telomere damage. We observed that m6A modification is abundant in R-loop enriched TERRA, and the m6A-mediated recruitment of hnRNPA2B1 to TERRA is critical for R-loop formation. Our findings suggest that m6A drives telomere targeting of TERRA via R-loops, and this m6A-mediated R-loop formation could be a widespread mechanism employed by other chromatin-interacting lncRNAs. Furthermore, treatment of ALT+ NB cells with a METTL3 inhibitor resulted in compromised telomere targeting of TERRA and accumulation of DNA damage at telomeres, indicating that METTL3 inhibition may represent a therapeutic approach for ALT+ NB.

Neuroblastoma Heterogeneity, Plasticity, and Emerging Therapies.

PURPOSE OF REVIEW: The evolving information of the initiation, tumor cell heterogeneity, and plasticity of childhood neuroblastoma has opened up new perspectives for developing therapies based on detailed knowledge of the disease. RECENT FINDINGS: The cellular origin of neuroblastoma has begun to unravel and there have been several reports on tumor cell heterogeneity based on transcriptional core regulatory circuitries that have given us important information on the biology of neuroblastoma as a developmental disease. This together with new insight of the tumor microenvironment which acts as a support for neuroblastoma growth has given us the prospect for designing better treatment approaches for patients with high-risk neuroblastoma. Here, we discuss these new discoveries and highlight some emerging therapeutic options. Neuroblastoma is a disease with multiple facets. Detailed biological and molecular knowledge on neuroblastoma initiation, heterogeneity, and the communications between cells in the tumor microenvironment holds promise for better therapies.

Transcriptional profiling demonstrates altered characteristics of CD8+ cytotoxic T-cells and regulatory T-cells in TP53-mutated acute myeloid leukemia.

BACKGROUND: Acute myeloid leukemia (AML) patients have limited effect from T-cell-based therapies, such as PD-1 and CTLA-4 blockade. However, recent data indicate that AML patients with TP53 mutation have higher immune infiltration and other immunomodulatory therapies could thus potentially be effective. Here, we performed the transcriptional analysis of distinct T-cell subpopulations from TP53-mutated AML to identify gene expression signatures suggestive of altered functional properties. METHODS: CD8+ cytotoxic T lymphocytes (CTLs), conventional helper T cells (Th), and regulatory T cells (Tregs) were sorted from peripheral blood of AML patients with TP53 mutation (n = 5) and healthy donors (n = 3), using FACS, and the different subpopulations were subsequently subjected to RNA-sequencing. Differentially expressed genes were identified and gene set enrichment analysis (GSEA) was performed to outline altered pathways and exhaustion status. Also, expression levels for a set of genes encoding established and emerging immuno-oncological targets were defined. RESULTS: The results showed altered transcriptional profiles for each of the T-cell subpopulations from TP53-mutated AML as compared to control subjects. IFN-α and IFN-γ signaling were stronger in TP53-mutated AML for both CTLs and Tregs. Furthermore, in TP53-mutated AML as compared to healthy controls, Tregs showed gene expression signatures suggestive of metabolic adaptation to their environment, whereas CTLs exhibited features of exhaustion/dysfunction with a stronger expression of TIM3 as well as enrichment of a gene set related to exhaustion. CONCLUSIONS: The results provide insights on mechanisms underlying the inadequate immune response to leukemic cells in TP53-mutated AML and open up for further exploration toward novel treatment regimens for these patients.

Pattern recognition receptor expression and maturation profile of dendritic cell subtypes in human tonsils and lymph nodes.

Dendritic cells (DCs) with capacity of antigen cross-presentation are of key interest for immunotherapy against cancer as they can induce antigen-specific cytotoxic T lymphocyte (CTL) responses. This study describes frequencies of DC subtypes in human tonsils and lymph nodes, and phenotypic aspects that may be targeted by adjuvant measures. From human tonsils and neck lymph nodes, DCs were identified through flow cytometry, and subsets of plasmacytoid DCs (pDCs) and myeloid DCs (mDCs) were investigated. Maturity status was assessed and surface receptors with CTL-promoting potentials were studied. CD123+ pDCs as well as CD1c+, CD141+, and CD1c-CD141- mDCs were detected in tonsils and lymph nodes. Both sites featured a similar presence of DC subsets, with CD123+ pDC being dominant and CD141+ mDCs least frequent. Based on CD80/CD86 expression, all DC subtypes featured a low degree of maturation. Expression of pattern recognition receptors (PRRs) CD206, CD207, DC-SIGN, TLR2, and TLR4, as well as the chemokine receptor XCR1, indicated DC subset-specific receptor profiles. We conclude that tonsils and lymph nodes share common features in terms of DC subset frequency and maturation as well as PRR and XCR1 expression pattern. Our work suggests that both sites may be considered for vaccine deposition in DC-mediated immunotherapy.

Patients' experiences of the caring encounter in health promotion practice: a qualitative study in Swedish primary health care.

BACKGROUND: Previous studies have reported that organizational structures and cultures in primary health care are obstacles to district nurses doing successful work in health promotion practice (HPP). Because organizational structures are not easily changed, Jean Watson's Attending Nurse Caring Model (ANCM) was introduced and piloted at a primary health care center in Sweden, aiming to transform HPP so as to empower district nurses and increase their work satisfaction. AIM: To investigate patients' experiences of the caring encounter in HPP after introduction of the ANCM in Swedish primary health care, the aim being to explore the essential components of the caring encounter between patients and district nurses. METHODS: A descriptive and qualitative research design was used. Data collection was performed using individual face-to-face interviews with twelve patients at risk for developing CVD. Data analysis consisted of both deductive content analysis, using a categorization matrix based on the ANCM and, subsequently, inductive latent content analysis. RESULTS: The findings were abstracted into three themes: 1.'Feeling the deepest essence of being cared for': to be respected and being put at the center of the encounter; 2. 'Feeling acceptance and worth': being treated with openness and permissive attitudes, 3. 'Being in a supportive atmosphere that promotes hope': to feel trust and being trusted in the encounter, and being empowered by hope. The unifying main theme of the caring encounter was abstracted as 'Experiencing human dignity'. CONCLUSION: The present study revealed that the essence of the caring encounter between patients and district nurses in HPP is to be unconditionally accepted in an environment that inspires hope and encouragement. The ANCM seems to be a promising model to use for strengthening the caring encounter and supporting CVD patients in making healthy lifestyle choices. However, further studies of qualitative and quantitative designs are needed to investigate what the ANCM can contribute to HPP in Swedish primary health care.

Dendritic cell subpopulations in nasopharyngeal cancer.

Nasopharyngeal cancer (NPC) is associated with Epstein-Barr virus (EBV) and EBV antigen may be utilized for therapeutic purposes, including targeting of dendritic cells (DCs). Although DCs may be present in NPC, the information is limited and not up-to-date with current knowledge on DC subsets. In the present study, biopsies from untreated NPC were obtained and subjected to multicolor flow-cytometry focusing on DC subtype markers: CD123 for plasmacytoid DCs (pDCs); and CD1c and CD141 for myeloid DCs (mDCs). Furthermore, subset-specific expression of the C-lectin receptor (CLR) CD207 (also termed langerin) was assessed. pDCs and mDCs were detected in the NPC lesions, contributing to a frequency mean average of 0.78% of CD45+ leukocytes in situ. Different subpopulations, previously not described in NPC, were observed, including: CD123+ pDCs; CD1c+ mDCs; CD141+ mDCs; and CD1c-CD141- mDCs. A high frequency of CD1c+ mDCs expressing CD207 was observed, compared with other subsets. In conclusion, different DC subsets are present in NPC lesions. The CLR CD207, a selective endocytic marker on CD1c+ mDCs, may be targeted for therapeutic purposes to facilitate cross-presentation of antigens and aid cell-mediated antitumor effects.

Dual loyalties: Everyday ethical problems of registered nurses and physicians in combat zones.

BACKGROUND:: When healthcare personnel take part in military operations in combat zones, they experience ethical problems related to dual loyalties, that is, when they find themselves torn between expectations of doing caring and military tasks, respectively. AIM:: This article aims to describe how Swedish healthcare personnel reason concerning everyday ethical problems related to dual loyalties between care and military tasks when undertaking healthcare in combat zones. DESIGN:: Abductive qualitative design. PARTICIPANTS AND RESEARCH CONTEXT:: Individual interviews with 15 registered nurses and physicians assigned for a military operation in Mali. ETHICAL CONSIDERATIONS:: The participants signed up voluntarily, and requirements for informed consent and confidentiality were met. The research was approved by the Regional Ethics Review Board in Gothenburg (D no. 816-14; 24 November 2014). FINDINGS:: Three main categories emerged: reasons for not undertaking combat duties, reasons for undertaking combat duties and restricted loyalty to military duties, and 14 subcategories. Reasons for not undertaking combat duties were that it was not in their role, not according to ethical codes or humanitarian law or a breach towards patients. Reasons for undertaking combat duties were that humanitarian law does not apply or has to be treated pragmatically or that it is a case of force protection. Shortage of resources and competence were reasons for both doing and not doing military tasks. Under some circumstances, they could imagine undertaking military tasks: when under threat, if unseen or if not needed for healthcare duties. DISCUSSION/CONCLUSION:: These discrepant views suggest a lack of a common view on what is ethically acceptable or not, and therefore we suggest further normative discussion on how these everyday ethical problems should be interpreted in the light of humanitarian law and ethical codes of healthcare personnel and following this, further training in ethical reflection before going on military operations.

Human Bone Marrow-Derived Myeloid Dendritic Cells Show an Immature Transcriptional and Functional Profile Compared to Their Peripheral Blood Counterparts and Separate from Slan+ Non-Classical Monocytes.

The human bone marrow (BM) gives rise to all distinct blood cell lineages, including CD1c+ (cDC2) and CD141+ (cDC1) myeloid dendritic cells (DC) and monocytes. These cell subsets are also present in peripheral blood (PB) and lymphoid tissues. However, the difference between the BM and PB compartment in terms of differentiation state and immunological role of DC is not yet known. The BM may represent both a site for development as well as a possible effector site and so far, little is known in this light with respect to different DC subsets. Using genome-wide transcriptional profiling we found clear differences between the BM and PB compartment and a location-dependent clustering for cDC2 and cDC1 was demonstrated. DC subsets from BM clustered together and separate from the corresponding subsets from PB, which similarly formed a cluster. In BM, a common proliferating and immature differentiating state was observed for the two DC subsets, whereas DC from the PB showed a more immune-activated mature profile. In contrast, BM-derived slan+ non-classical monocytes were closely related to their PB counterparts and not to DC subsets, implying a homogenous prolife irrespective of anatomical localization. Additional functional tests confirmed these transcriptional findings. DC-like functions were prominently exhibited by PB DC. They surpassed BM DC in maturation capacity, cytokine production, and induction of CD4+ and CD8+ T cell proliferation. This first study on myeloid DC in healthy human BM offers new information on steady state DC biology and could potentially serve as a starting point for further research on these immune cells in healthy conditions as well as in diseases.

Adulthood transitions in health and welfare; a literature review.

AIM: The aim of the literature review was to describe how adulthood transition is used in health and welfare. DESIGN: A qualitative design with a deductive approach were used. METHODS: As material, 283 articles published in scientific journals, between 2011-August 2013, were selected. The search was conducted August 2013. The data were analysed and sorted in a categorization matrix. RESULTS: Transition was identified as a process mainly related to the four types previously identified; developmental, situational, health-illness and organizational transitions. Another one transition was also identified, lifestyle transition.

Profiling dendritic cell subsets in head and neck squamous cell tonsillar cancer and benign tonsils.

Dendritic cells (DCs) have a key role in orchestrating immune responses and are considered important targets for immunotherapy against cancer. In order to develop effective cancer vaccines, detailed knowledge of the micromilieu in cancer lesions is warranted. In this study, flow cytometry and human transcriptome arrays were used to characterize subsets of DCs in head and neck squamous cell tonsillar cancer and compare them to their counterparts in benign tonsils to evaluate subset-selective biomarkers associated with tonsillar cancer. We describe, for the first time, four subsets of DCs in tonsillar cancer: CD123+ plasmacytoid DCs (pDC), CD1c+, CD141+, and CD1c-CD141- myeloid DCs (mDC). An increased frequency of DCs and an elevated mDC/pDC ratio were shown in malignant compared to benign tonsillar tissue. The microarray data demonstrates characteristics specific for tonsil cancer DC subsets, including expression of immunosuppressive molecules and lower expression levels of genes involved in development of effector immune responses in DCs in malignant tonsillar tissue, compared to their counterparts in benign tonsillar tissue. Finally, we present target candidates selectively expressed by different DC subsets in malignant tonsils and confirm expression of CD206/MRC1 and CD207/Langerin on CD1c+ DCs at protein level. This study descibes DC characteristics in the context of head and neck cancer and add valuable steps towards future DC-based therapies against tonsillar cancer.

Transcriptional profiling reveals functional dichotomy between human slan+ non-classical monocytes and myeloid dendritic cells.

Human 6-sulfo LacNac-positive (slan+) cells have been subject to a paradigm debate. They have previously been classified as a distinct dendritic cell (DC) subset. However, evidence has emerged that they may be more related to monocytes than to DCs. To gain deeper insight into the functional specialization of slan+ cells, we have compared them with both conventional myeloid DC subsets (CD1c+ and CD141+) in human peripheral blood (PB). With the use of genome-wide transcriptional profiling, as well as functional tests, we clearly show that slan+ cells form a distinct, non-DC-like population. They cluster away from both DC subsets, and their gene-expression profile evidently suggests involvement in distinct inflammatory processes. An extensive transcriptional meta-analysis confirmed the relationship of slan+ cells with the monocytic compartment rather than with DCs. From a functional perspective, their ability to prime CD4+ and CD8+ T cells is relatively low. Combined with the finding that "antigen presentation by MHC class II" is at the top of under-represented pathways in slan+ cells, this points to a minimal role in directing adaptive T cell immunity. Rather, the higher expression levels of complement receptors on their cell surface, together with their high secretion of IL-1ß and IL-6, imply a specific role in innate inflammatory processes, which is consistent with their recent identification as non-classical monocytes. This study extends our knowledge on DC/monocyte subset biology under steady-state conditions and contributes to our understanding of their role in immune-mediated diseases and their potential use in immunotherapeutic strategies.

Health Promotion in Practice-District Nurses׳ Experiences of Working with Health Promotion and Lifestyle Interventions Among Patients at Risk of Developing Cardiovascular Disease.

OBJECTIVE: Health Promotion Practice (HPP) has the objective to promote a healthier lifestyle and reduce the risk of disease. The aim of this study was to examine district nurses׳ experiences of working with health preventive actions among patients with risk factors for cardiovascular disease (CVD), and to identify facilitators and obstacles in HPP. DESIGN/SETTING: The study was carried out with a qualitative approach where individual semistructured interviews were performed with a total of 12 district nurses in primary care. Data transcripts were analyzed with a manifest content analysis. FINDINGS: Five categories were identified. Firstly, informants regarded HPP as the core essence of their work. Secondly, counseling and coaching were reported as crucial elements in working with HPP. Thirdly, informants identified tools such as motivational interviewing (MI) to facilitate HPP. In the fourth category facilitators and barriers of HPP appeared, consisting of both positive and negative attitudes and presence as well as lack of organizational culture and structure. Finally, some informants were dissatisfied with HPP and viewed it as compulsory or as a burden, while others were satisfied and experienced it as a stimulating challenge. CONCLUSION: This study identified that HPP is the core of the district nurses׳ work to promote a healthier lifestyle in individuals with CVD. Organizational structures and culture need to be improved in order to support district nurses to successfully work with HPP. To optimize health promotion and strengthen patients׳ self-care, it is recommended that HPP include holistic elements of care.

High-Yield Birth-Cohort Hepatitis C Virus Screening and Linkage to Care Among Underserved African Americans, Atlanta, Georgia, 2012-2013.

OBJECTIVE: Hepatitis C virus (HCV) infection disproportionately affects certain populations, including those born between 1945 and 1965 (i.e., baby boomers) and African Americans. As part of the Hepatitis Testing and Linkage to Care initiative, which promoted hepatitis B and hepatitis C screening, posttest counseling, and linkage to care at 34 U.S. sites, we conducted routine HCV screening to identify previously undiagnosed, primarily African American baby boomers with chronic hepatitis C infection and link them to care. METHODS: We launched the Internal Medicine Trainees Identifying and Linking to Treatment for Hepatitis C (TILT-C) initiative at the Grady Memorial Hospital Primary Care Center and Grady Liver Clinic in Atlanta, Georgia, in October 2012, and present results from the first year. TILT-C faculty implemented an electronic medical record prompt and conducted educational sessions to boost HCV screening. A project coordinator tracked testing outcomes and linked HCV-positive patients to care. RESULTS: Of 2,894 patients tested for anti-HCV, 201 (6.9%) tested positive. Men had a significantly higher (p<0.001) prevalence of HCV infection than women, with 106 of 1,091 (9.7%) men compared with 95 of 1,803 (5.3%) women testing anti-HCV positive. A total of 174 of 201 (86.6%) anti-HCV-positive patients received HCV ribonucleic acid (RNA) testing. Of 124 patients with a positive HCV RNA test, 122 were referred to care and 120 attended the first appointment. CONCLUSION: The TILT-C screening program was feasible and effective in detecting previously undiagnosed HCV infection and linking patients to care. The unexpectedly high prevalence of HCV infection in this primarily African American, baby boomer population underscores the need for aggressive HCV screening efforts in similar populations.

Allergen-Specific Immunotherapy Alters the Frequency, as well as the FcR and CLR Expression Profiles of Human Dendritic Cell Subsets.

Allergen-specific immunotherapy (AIT) induces tolerance and shifts the Th2 response towards a regulatory T-cell profile. The underlying mechanisms are not fully understood, but dendritic cells (DC) play a vital role as key regulators of T-cell responses. DCs interact with allergens via Fc receptors (FcRs) and via certain C-type lectin receptors (CLRs), including CD209/DC-SIGN, CD206/MR and Dectin-2/CLEC6A. In this study, the effect of AIT on the frequencies as well as the FcR and CLR expression profiles of human DC subsets was assessed. PBMC was isolated from peripheral blood from seven allergic donors before and after 8 weeks and 1 year of subcutaneous AIT, as well as from six non-allergic individuals. Cells were stained with antibodies against DC subset-specific markers and a panel of FcRs and CLRs and analyzed by flow cytometry. After 1 year of AIT, the frequency of CD123+ DCs was increased and a larger proportion expressed FcεRI. Furthermore, the expression of CD206 and Dectin-2 was reduced on CD141+ DCs after 1 year of treatment and CD206 as well as Dectin-1 was additionally down regulated in CD1c+ DCs. Interestingly, levels of DNGR1/CLEC9A on CD141+ DCs were increased by AIT, reaching levels similar to cells isolated from non-allergic controls. The modifications in phenotype and occurrence of specific DC subsets observed during AIT suggest an altered capacity of DC subsets to interact with allergens, which can be part of the mechanisms by which AIT induces allergen tolerance.

Increased levels of IL-6 in the cerebrospinal fluid of patients with chronic schizophrenia--significance for activation of the kynurenine pathway.

BACKGROUND: Accumulating evidence indicates that schizophrenia is associated with brain immune activation. While a number of reports suggest increased cytokine levels in patients with schizophrenia, many of these studies have been limited by their focus on peripheral cytokines or confounded by various antipsychotic treatments. Here, well-characterized patients with schizophrenia, all receiving olanzapine treatment, and healthy volunteers were analyzed with regard to cerebrospinal fluid (CSF) levels of cytokines. We correlated the CSF cytokine levels to previously analyzed metabolites of the kynurenine (KYN) pathway. METHODS: We analyzed the CSF from patients and controls using electrochemiluminescence detection with regard to cytokines. Cell culture media from human cortical astrocytes were analyzed for KYN and kynurenic acid (KYNA) using high-pressure liquid chromatography or liquid chromatography/mass spectrometry. RESULTS: We included 23 patients and 37 controls in our study. Patients with schizophrenia had increased CSF levels of interleukin (IL)-6 compared with healthy volunteers. In patients, we also observed a positive correlation between IL-6 and the tryptophan:KYNA ratio, indicating that IL-6 activates the KYN pathway. In line with this, application of IL-6 to cultured human astrocytes increased cell medium concentration of KYNA. LIMITATIONS: The CSF samples had been frozen and thawed twice before analysis of cytokines. Median age differed between patients and controls. When appropriate, all present analyses were adjusted for age. CONCLUSION: We have shown that IL-6, KYN and KYNA are elevated in patients with chronic schizophrenia, strengthening the idea of brain immune activation in patients with this disease. Our concurrent cell culture and clinical findings suggest that IL-6 induces the KYN pathway, leading to increased production of the N-methyl-D-aspartate receptor antagonist KYNA in patients with schizophrenia.

Imbalanced kynurenine pathway in schizophrenia.

Several studies suggest a role for kynurenic acid (KYNA) in the pathophysiology of schizophrenia. It has been proposed that increased brain KYNA levels in schizophrenia result from a pathological shift in the kynurenine pathway toward enhanced KYNA formation, away from the other branch of the pathway leading to quinolinic acid (QUIN). Here we investigate the levels of QUIN in cerebrospinal fluid (CSF) of patients with schizophrenia and healthy controls, and relate those to CSF levels of KYNA and other kynurenine metabolites from the same individuals. CSF QUIN levels from stable outpatients treated with olanzapine (n = 22) and those of controls (n = 26) were analyzed using liquid chromatography-mass spectrometry. No difference in CSF QUIN levels between patients and controls was observed (20.6 ± 1.5 nM vs. 18.2 ± 1.1 nM, P = 0.36). CSF QUIN was positively correlated to CSF kynurenine and CSF KYNA in patients but not in controls. The CSF QUIN/KYNA ratio was lower in patients than in controls (P = 0.027). In summary, the present study offers support for an over-activated and imbalanced kynurenine pathway, favoring the production of KYNA over QUIN in patients with schizophrenia.

What are internal medicine residents missing? A communication needs assessment of outpatient clinical encounters.

OBJECTIVE: In order to guide curricular innovation, we looked at the feasibility and utility of performing a targeted needs assessment of the communication skills of PGY2 internal medicine (IM) residents in their continuity clinic, utilizing faculty direct observation with a validated instrument for communication skills evaluation. METHODS: A convenience sample of PGY2 residents in the Emory University School of Medicine IM Residency Program was invited to participate. Using the SEGUE Framework, a checklist of medical communication tasks, faculty assessed residents during a clinic encounter. RESULTS: Thirty out of 53 (57%) PGY2 residents were assessed. SEGUE results indicate residents were most likely to "maintain patient's privacy" (100%), "greet patient appropriately" (97%) and "check/clarify information" (100%). Residents were least likely to "acknowledge waiting time" (7%), "explore psychosocial/emotional factors" (27%) and "outline agenda for visit" (33%). CONCLUSION: The SEGUE Framework is a feasible tool to evaluate the communication skills of IM residents in a clinic setting. Many PGY2 IM residents in a large, urban practice do not elicit important psychosocial information during outpatient clinic visits. PRACTICE IMPLICATIONS: More observation and evaluation of residents' communication skills are needed, with emphasis on building skills to "Understand the Patient's Perspective."

Experiences of Swedish military medical personnel in combat zones: adapting to competing loyalties.

OBJECTIVES: The aim of this qualitative study is to explore the Swedish military personnel's experience of what it means to perform a caring role in a combat zone. This study assesses the challenges faced by military medical personnel in the context of a combat zone. METHODS: The design was descriptive with a qualitative inductive approach. Twenty military medical personnel (physicians, nurses, and combat lifesavers) were interviewed individually. They had been involved in international military operations between 2009 and 2012. This study was analyzed using qualitative content analysis. RESULTS: The analysis produced four categories: being in a primarily noncaring organization, caring in emotionally charged relationships, lacking an open dialog about expectations of killing and having to prioritize scarce resources. CONCLUSIONS: This study shows that medical personnel easily adapt to a military setting. They care but also perform other tasks when they are in a combat zone. The medical personnel want to give care to host nation but use drugs they can spare.

Circulating CD1c(+) DCs are superior at activating Th2 responses upon Phl p stimulation compared with basophils and pDCs.

The contributing role of circulating human dendritic cell (DC) populations and basophils in the presentation and augmentation of Th2 responses remains to be determined. The present study aimed at elucidating the functional role of CD1c(+) myeloid DCs (mDCs), CD123(+) plasmacytoid DCs (pDCs), monocyte-derived DCs and basophils in allergen presentation and Th2 activation. By coculturing Phleum pratense (Phl p)-pulsed CD1c(+) mDCs, CD123(+) pDCs, monocyte-derived DCs and basophils with autologous CD4(+) effector memory T cells, we assessed T-cell proliferation as well as the frequency of interleukin-4- and interferon-γ-producing T cells. Interestingly, a Th2-stimulating ability was observed for Phl p-challenged CD1c(+) mDCs and monocyte-derived DCs, while CD123(+) pDCs and basophils did not affect the Th-balance. In addition, both Phl p-pulsed CD1c(+) mDCs and monocyte-derived DCs stimulated increased T-cell proliferation compared to basophils and CD123(+) pDCs. Together, these results point to a prominent role for circulating CD1c(+) mDCs in allergen presentation and augmentation of Th2 responses, making them promising therapeutic targets for Type I hypersensitivity reactions.

Human blood dendritic cell subsets exhibit discriminative pattern recognition receptor profiles.

Dendritic cells (DCs) operate as the link between innate and adaptive immunity. Their expression of pattern recognition receptors (PRRs), such as Toll-like receptors (TLRs) and C-type lectin receptors (CLRs), enables antigen recognition and mediates appropriate immune responses. Distinct subsets of human DCs have been identified; however their expression of PRRs is not fully clarified. Expressions of CLRs by DC subpopulations, in particular, remain elusive. This study aimed to identify and compare PRR expressions on human blood DC subsets, including CD1c(+) , CD141(+) and CD16(+) myeloid DCs and CD123(+) plasmacytoid DCs, in order to understand their capacity to recognize different antigens as well as their responsiveness to PRR-directed targeting. Whole blood was obtained from 13 allergic and six non-allergic individuals. Mononuclear cells were purified and multi-colour flow cytometry was used to assess the expression of 10 CLRs and two TLRs on distinct DC subsets. PRR expression levels were shown to differ between DC subsets for each PRR assessed. Furthermore, principal component analysis and random forest test demonstrated that the PRR profiles were discriminative between DC subsets. Interestingly, CLEC9A was expressed at lower levels by CD141(+) DCs from allergic compared with non-allergic donors. The subset-specific PRR expression profiles suggests individual responsiveness to PRR-targeting and supports functional specialization.