CEBPß regulation of endogenous IGF-1 in adult sensory neurons can be mobilized to overcome diabetes-induced deficits in bioenergetics and axonal outgrowth.

Aberrant insulin-like growth factor 1 (IGF-1) signaling has been proposed as a contributing factor to the development of neurodegenerative disorders including diabetic neuropathy, and delivery of exogenous IGF-1 has been explored as a treatment for Alzheimer's disease and amyotrophic lateral sclerosis. However, the role of autocrine/paracrine IGF-1 in neuroprotection has not been well established. We therefore used in vitro cell culture systems and animal models of diabetic neuropathy to characterize endogenous IGF-1 in sensory neurons and determine the factors regulating IGF-1 expression and/or affecting neuronal health. Single-cell RNA sequencing (scRNA-Seq) and in situ hybridization analyses revealed high expression of endogenous IGF-1 in non-peptidergic neurons and satellite glial cells (SGCs) of dorsal root ganglia (DRG). Brain cortex and DRG had higher IGF-1 gene expression than sciatic nerve. Bidirectional transport of IGF-1 along sensory nerves was observed. Despite no difference in IGF-1 receptor levels, IGF-1 gene expression was significantly (P < 0.05) reduced in liver and DRG from streptozotocin (STZ)-induced type 1 diabetic rats, Zucker diabetic fatty (ZDF) rats, mice on a high-fat/ high-sugar diet and db/db type 2 diabetic mice. Hyperglycemia suppressed IGF-1 gene expression in cultured DRG neurons and this was reversed by exogenous IGF-1 or the aldose reductase inhibitor sorbinil. Transcription factors, such as NFAT1 and CEBPß, were also less enriched at the IGF-1 promoter in DRG from diabetic rats vs control rats. CEBPß overexpression promoted neurite outgrowth and mitochondrial respiration, both of which were blunted by knocking down or blocking IGF-1. Suppression of endogenous IGF-1 in diabetes may contribute to neuropathy and its upregulation at the transcriptional level by CEBPß can be a promising therapeutic approach.

Introducing clinical pharmacy specialists into interprofessional primary care teams: Assessing pharmacists' team integration and access to care for rural patients.

ABSTRACT: Clinical pharmacy specialists (CPS) were deployed nationally to improve care access and relieve provider burden in primary care.The aim of this study was to assess CPS integration in primary care and the Clinical Pharmacy Specialist Rural Veteran Access (CRVA) initiative's effectiveness in improving access.Concurrent embedded mixed-methods evaluation of participating CRVA CPS and their clinical team members (primary care providers, others).Health care providers on primary care teams in Veterans Health Administration (VHA).Perceived CPS integration in comprehensive medication management assessed using the MUPM and semi-structured interviews, and access measured with patient encounter data.There were 496,323 medical encounters with CPS in primary care over a 3-year period. One hundred twenty-four CPS and 1177 other clinical team members responded to a self-administered web-based questionnaire, with semi-structured interviews completed by 22 CPS and clinicians. Survey results indicated that all clinical provider groups rank CPS as making major contributions to CMM. CPS ranked themselves as contributing more to CMM than did their physician team members. CPS reported higher job satisfaction, less burn out, and better role fit; but CPS gave lower scores for communication and decision making as clinic organizational attributes. Themes in provider interviews focused on value of CPS in teams, relieving provider burden, facilitators to integration, and team communication issues.This evaluation indicates good integration of CPS on primary care teams as perceived by other team members despite some communication and role clarification challenges. CPS may play an important role in improving access to primary care.

Access to Lung Cancer Screening in the Veterans Health Administration: Does Geographic Distribution Match Need in the Population?

BACKGROUND: Studies show uneven access to Medicare-approved lung cancer screening (LCS) programs across the United States. The Veterans Health Administration (VA), the largest national US integrated health system, is potentially well positioned to coordinate LCS services across regional units to ensure that access matches distribution of need nationally. RESEARCH QUESTION: To what extent does LCS access (considering both VA and partner sites) and use match the distribution of eligible Veterans at state and regional levels? METHODS: In this retrospective analysis, we identified LCS examinations in VA facilities between 2013 and 2019 from the VA Corporate Data Warehouse and plotted VA facilities with LCS geographically. We compared estimated LCS rates (unique Veterans screened per LCS-eligible population) across states and VA regional units. Finally, we assessed whether the VA's new partnership with the GO2 Foundation for Lung Cancer (which includes more than 750 LCS centers) closes geographic gaps in LCS access. RESULTS: We identified 71,898 LCS examinations in 96 of 139 (69.1%) VA facilities in 44 states between 2013 and 2019, with substantial variation across states (0-8 VA LCS facilities per state). Screening rates among eligible Veterans in the population varied more than 30-fold across regional networks (rate ratio, 33.6; 95% CI, 30.8-36.7 for VA New England vs Veterans Integrated Service Network 4), with weak correlation between eligible populations and LCS rates (coefficient, -0.30). Partnering with the GO2 Foundation for Lung Cancer expands capacity and access (eg, all states now have ≥ 1 VA or partner LCS site), but 9 of the 12 states with the highest proportions of rural Veterans still have ≤ 3 total LCS facilities. INTERPRETATION: Disparities in LCS access exist based on where Veterans live, particularly for rural Veterans, even after partnering with the GO2 Foundation for Lung Cancer. The nationally integrated VA system has an opportunity to leverage regional resources to distribute and coordinate LCS services better to ensure equitable access.

Confirmation Bias as a Factor in Pharmacy Student Assessment of Research Study Quality.

Objective. To determine whether pharmacy students' prior beliefs and attitudes about drug products and dietary supplements affected their ability to analyze the quality of research study abstracts and use them in making drug recommendations to patients. Methods. Fifty-nine Doctor of Pharmacy (PharmD) students in a drug literature course were randomly assigned to receive one of two forms to evaluate four drug literature abstracts of varying quality and study design. On each form, there were two abstracts that had been taken directly from published research studies and two abstracts in which a different product had been substituted for the actual product studied. Pharmacy students completed a questionnaire about the studies to determine whether their evaluation of quality was affected by their prior opinions about the products. Results. Students correctly recognized the relative quality of the studies. However, after reading abstracts of research articles that were identical except for the product named, students were still more likely to recommend drugs approved by the Food and Drug Administration than dietary supplements. Conclusion. Pharmacy students' evaluation of clinical research studies was mildly influenced by confirmation bias but more so by the quality of the research.

Effects of various dietary supplements on inflammatory processes in primary canine chondrocytes as a model of osteoarthritis.

The use of dietary supplements as an alternative treatment for joint-related pathologies such as osteoarthritis (OA) is increasing. However, there is little scientific evidence to support the intended use. The aim of this study was to evaluate the anti-inflammatory effects of creatine- and amino acid-based supplements in primary cultured canine chondrocytes (CnCs) as an in-vitro model of OA and compare the effects to more commonly used agents, such as the non-steroidal anti-inflammatory drug (NSAID), carprofen, and the joint supplement, glucosamine (GS). CnCs were stimulated with interleukin-1ß (IL-1ß) and the subsequent release of prostaglandin E2 (PGE2) and tumor necrosis factor alpha (TNFα) was measured using an enzyme-linked immunosorbent assay (ELISA). Changes in oxylipins were also assessed using high-performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS). All compounds examined were able to significantly reduce the release of PGE2 and TNFα and were associated with reductions in cyclooxygenase-2 (COX-2) expression and nuclear factor-kappaB (NF-κB) phosphorylation. The creatine- and amino acids-based supplements also altered the profile of oxylipins produced. All compounds examined were less effective at reducing the release of PGE2 than carprofen. Carprofen significantly increased release of TNFα from CnCs, however, while the other agents reduced TNFα release. This study suggests that creatine- and amino acid-based supplements may have a beneficial role in preventing inflammation within the joint and that further studies are warranted.

L'utilisation de suppléments alimentaires à titre de traitement alternatif pour les pathologies associées aux articulations telle que l'arthrose (OA) est en augmentation. Toutefois, il y a peu d'évidences scientifiques qui supportent l'utilisation proposée. L'objectif de la présente étude était d'évaluer les effets anti-inflammatoires de suppléments à base de créatine et d'acides aminés sur des cultures primaires de chondrocytes canins (CnCs) utilisés comme modèle in vitro d'OA et de comparer les effets à des agents plus communément utilisés, tel que l'agent anti-inflammatoire non-stéroïdien (AINS) carprofen, et le supplément articulaire, glucosamine (GS). Les CnCs furent stimulés avec de l'interleukine-1ß (IL-1ß) et la libération subséquente de prostaglandine E2 (PGE2) et le facteur nécrosant de tumeur alpha (TNFα) fut mesurée par épreuve immuno-enzymatique (ELISA). Les changements dans les oxylipines furent également mesurés par chromatographie en phase liquide à haute performance/spectrométrie de masse tandem (HPLC/MS/MS). Tous les composés examinés étaient en mesure de réduire significativement la libération de PGE2 et de TNFα et étaient associés avec des réductions d'expression de cyclooxygénase-2 (COX-2) et de phosphorylation du facteur nucléaire kappaB (NF-κB). Les suppléments à base de créatine et d'acides aminés ont également altéré le profil des oxylipines produits. Tous les composés examinés étaient moins efficaces que le carprofen pour réduire la libération de PGE2. Le carprofen augmentait significativement la libération de TNFα par les CnCs, alors que les autres agents la réduisaient. La présente étude suggère que les suppléments à base de créatine et d'acides aminés pourraient avoir un rôle bénéfique dans la prévention de l'inflammation dans l'articulation et que des études supplémentaires sont requises.(Traduit par Docteur Serge Messier).

Systems change to improve tobacco use identification and referral in the chiropractic setting: a pilot study.

Background: Tobacco use remains a leading cause of death and disability in the United States. Health professionals need to address the use of tobacco products by their patients, but chiropractic clinical systems often remain unsupported and underappreciated in their role to facilitate tobacco use cessation. Methods: This pilot study tested an intervention to assist a chiropractic community to implement sustainable health systems changes for tobacco use based on U.S. Public Health Service guidelines. Chiropractors were educated on the Ask, Advise, Refer (AAR) approach, provided with ongoing guidance, and followed for six months to assess systems change. The study was conducted from March 2016 to July 2017. Results: Evidence of a systematic process in place to conduct AAR was present in all clinics by the end of the fourth month of the intervention period. Although no clinic had sustained health system change for full AAR, all six of the clinics made progress in the individual AAR components. Furthermore, five clinics achieved sustained system change for the Ask component, as after systems change was achieved, the rate of tobacco user identifications did not drop below 50%. For the Advise component, five clinics succeeded in having individual months of ≥50% of tobacco users being advised, and three clinics achieved the formal definition of systems change. For the Refer component, no clinic achieved system change, although four had individual months of ≥50% of tobacco users being referred. The patient quit rate was 13.3% (n = 15) for the 30-day follow-up and 16.7% (n = 6) for the three-month follow-up. Conclusions: This study demonstrates the feasibility of implementing a health systems change in the chiropractic setting to identify tobacco users, to advise them to quit, and to refer users for cessation services.

Development and Validation of a Tool to Identify Patients With Type 2 Diabetes at High Risk of Hypoglycemia-Related Emergency Department or Hospital Use.

Importance: Hypoglycemia-related emergency department (ED) or hospital use among patients with type 2 diabetes (T2D) is clinically significant and possibly preventable. Objective: To develop and validate a tool to categorize risk of hypoglycemic-related utilization in patients with T2D. Design, Setting, and Participants: Using recursive partitioning with a split-sample design, we created a classification tree based on potential predictors of hypoglycemia-related ED or hospital use. The resulting model was transcribed into a tool for practical application and tested in 1 internal and 2 fully independent, external samples. Development and internal testing was conducted in a split sample of 206 435 patients with T2D from Kaiser Permanente Northern California (KPNC), an integrated health care system. The tool was externally tested in 1 335 966 Veterans Health Administration and 14 972 Group Health Cooperative patients with T2D. Exposures: Based on a literature review, we identified 156 candidate predictor variables (prebaseline exposures) using data collected from electronic medical records. Main Outcomes and Measures: Hypoglycemia-related ED or hospital use during 12 months of follow-up. Results: The derivation sample (n = 165 148) had a mean (SD) age of 63.9 (13.0) years and included 78 576 (47.6%) women. The crude annual rate of at least 1 hypoglycemia-related ED or hospital encounter in the KPNC derivation sample was 0.49%. The resulting hypoglycemia risk stratification tool required 6 patient-specific inputs: number of prior episodes of hypoglycemia-related utilization, insulin use, sulfonylurea use, prior year ED use, chronic kidney disease stage, and age. We categorized the predicted 12-month risk of any hypoglycemia-related utilization as high (>5%), intermediate (1%-5%), or low (<1%). In the internal validation sample, 2.0%, 10.7%, and 87.3% were categorized as high, intermediate, and low risk, respectively, with observed 12-month hypoglycemia-related utilization rates of 6.7%, 1.4%, and 0.2%, respectively. There was good discrimination in the internal validation KPNC sample (C statistic = 0.83) and both external validation samples (Veterans Health Administration: C statistic = 0.81; Group Health Cooperative: C statistic = 0.79). Conclusions and Relevance: This hypoglycemia risk stratification tool categorizes the 12-month risk of hypoglycemia-related utilization in patients with T2D using only 6 inputs. This tool could facilitate targeted population management interventions, potentially reducing hypoglycemia risk and improving patient safety and quality of life.

Broccoli-Derived Nanoparticle Inhibits Mouse Colitis by Activating Dendritic Cell AMP-Activated Protein Kinase.

The intestinal immune system is continuously exposed to massive amounts of nanoparticles derived from food. Whether nanoparticles from plants we eat daily have a role in maintaining intestinal immune homeostasis is poorly defined. Here, we present evidence supporting our hypothesis that edible nanoparticles regulate intestinal immune homeostasis by targeting dendritic cells (DCs). Using three mouse colitis models, our data show that orally given nanoparticles isolated from broccoli extracts protect mice against colitis. Broccoli-derived nanoparticle (BDN)-mediated activation of adenosine monophosphate-activated protein kinase (AMPK) in DCs plays a role in not only prevention of DC activation but also induction of tolerant DCs. Adoptively transferring DCs pre-pulsed with total BDN lipids, but not sulforaphane (SFN)-depleted BDN lipids, prevented DSS-induced colitis in C57BL/6 (B6) mice, supporting the role of BDN SFN in the induction of DC tolerance. Adoptively transferring AMPK+/+, but not AMPK-/-, DCs pre-pulsed with SFN prevented DSS-induced colitis in B6 mice, further supporting the DC AMPK role in SFN-mediated prevention of DSS-induced colitis. This finding could open new preventive or therapeutic avenues to address intestinal-related inflammatory diseases via activating AMPK.

Grapefruit-derived nanovectors deliver miR-18a for treatment of liver metastasis of colon cancer by induction of M1 macrophages.

Liver metastasis accounts for many of the cancer deaths in patients. Effective treatment for metastatic liver tumors is not available. Here, we provide evidence for the role of miR-18a in the induction of liver M1 (F4/80+interferon gamma (IFNγ)+IL-12+) macrophages. We found that miR-18a encapsulated in grapefruit-derived nanovector (GNV) mediated inhibition of liver metastasis that is dependent upon the induction of M1 (F4/80+IFNγ+IL-12+) macrophages; depletion of macrophages eliminated its anti-metastasis effect. Furthermore, the miR-18a mediated induction of macrophage IFNγ by targeting IRF2 is required for subsequent induction of IL-12. IL-12 then activates natural killer (NK) and natural killer T (NKT) cells for inhibition of liver metastasis of colon cancer. This conclusion is supported by the fact that knockout of IFNγ eliminates miR-18a mediated induction of IL-12, miR-18a treatment has an anti-metastatic effects in T cell deficient mice but there is no anti-metastatic effect on NK and NKT deficient mice. Co-delivery of miR-18a and siRNA IL-12 to macrophages did not result in activation of co-cultured NK and NKT cells. Taken together our results indicate that miR-18a can act as an inhibitor for liver metastasis through induction of M1 macrophages.

Grapefruit-derived Nanovectors Delivering Therapeutic miR17 Through an Intranasal Route Inhibit Brain Tumor Progression.

The lack of access to the brain is a major obstacle for central nervous system drug development. In this study, we demonstrate the capability of a grapefruit-derived nanovector (GNV) to carry miR17 for therapeutic treatment of mouse brain tumor. We show that GNVs coated with folic acid (FA-GNVs) are enhanced for targeting the GNVs to a folate receptor-positive GL-26 brain tumor. Additionally, FA-GNV-coated polyethylenimine (FA-pGNVs) not only enhance the capacity to carry RNA, but the toxicity of the polyethylenimine is eliminated by the GNVs. Intranasal administration of miR17 carried by FA-pGNVs led to rapid delivery of miR17 to the brain that was selectively taken up by GL-26 tumor cells. Mice treated intranasally with FA-pGNV/miR17 had delayed brain tumor growth. Our results demonstrate that this strategy may provide a noninvasive therapeutic approach for treating brain-related disease through intranasal delivery.

The origin and genetic differentiation of the socially parasitic aphid Tamalia inquilinus.

Social and brood parasitisms are nonconsumptive forms of parasitism involving the exploitation of the colonies or nests of a host. Such parasites are often related to their hosts and may evolve in various ecological contexts, causing evolutionary constraints and opportunities for both parasites and their hosts. In extreme cases, patterns of diversification between social parasites and their hosts can be coupled, such that diversity of one is correlated with or even shapes the diversity of the other. Aphids in the genus Tamalia induce galls on North American manzanita (Arctostaphylos) and related shrubs (Arbutoideae) and are parasitized by nongalling social parasites or inquilines in the same genus. We used RNA sequencing to identify and generate new gene sequences for Tamalia and performed maximum-likelihood, Bayesian and phylogeographic analyses to reconstruct the origins and patterns of diversity and host-associated differentiation in the genus. Our results indicate that the Tamalia inquilines are monophyletic and closely related to their gall-forming hosts on Arctostaphylos, supporting a previously proposed scenario for origins of these parasitic aphids. Unexpectedly, population structure and host-plant-associated differentiation were greater in the non-gall-inducing parasites than in their gall-inducing hosts. RNA-seq indicated contrasting patterns of gene expression between host aphids and parasites, and perhaps functional differences in host-plant relationships. Our results suggest a mode of speciation in which host plants drive within-guild diversification in insect hosts and their parasites. Shared host plants may be sufficient to promote the ecological diversification of a network of phytophagous insects and their parasites, as exemplified by Tamalia aphids.

Grapefruit-Derived Nanovectors Use an Activated Leukocyte Trafficking Pathway to Deliver Therapeutic Agents to Inflammatory Tumor Sites.

Inflammation is a hallmark of cancer. Activated immune cells are intrinsically capable of homing to inflammatory sites. Using three inflammatory-driven disease mouse models, we show that grapefruit-derived nanovectors (GNV) coated with inflammatory-related receptor enriched membranes of activated leukocytes (IGNVs) are enhanced for homing to inflammatory tumor tissues. Blocking LFA-1 or CXCR1 and CXCR2 on the IGNVs significantly inhibits IGNV homing to the inflammatory tissue. The therapeutic potential of IGNVs was further demonstrated by enhancing the chemotherapeutic effect as shown by inhibition of tumor growth in two tumor models and inhibiting the inflammatory effects of dextran sulfate sodium-induced mouse colitis. The fact that IGNVs are capable of homing to inflammatory tissue and that chemokines are overexpressed in diseased human tissue provides the rationale for using IGNVs to more directly deliver therapeutic agents to inflammatory tumor sites and the rationale for the use of IGNVs as treatment for certain cancers in personalized medicine.

Magnetic field enhanced convective diffusion of iron oxide nanoparticles in an osmotically disrupted cell culture model of the blood-brain barrier.

PURPOSE: The present study examines the use of an external magnetic field in combination with the disruption of tight junctions to enhance the permeability of iron oxide nanoparticles (IONPs) across an in vitro model of the blood-brain barrier (BBB). The feasibility of such an approach, termed magnetic field enhanced convective diffusion (MFECD), along with the effect of IONP surface charge on permeability, was examined. METHODS: The effect of magnetic field on the permeability of positively (aminosilane-coated [AmS]-IONPs) and negatively (N-(trimethoxysilylpropyl)ethylenediaminetriacetate [EDT]-IONPs) charged IONPs was evaluated in confluent monolayers of mouse brain endothelial cells under normal and osmotically disrupted conditions. RESULTS: Neither IONP formulation was permeable across an intact cell monolayer. However, when tight junctions were disrupted using D-mannitol, flux of EDT-IONPs across the bEnd.3 monolayers was 28%, increasing to 44% when a magnetic field was present. In contrast, the permeability of AmS-IONPs after osmotic disruption was less than 5%. The cellular uptake profile of both IONPs was not altered by the presence of mannitol. CONCLUSIONS: MFECD improved the permeability of EDT-IONPs through the paracellular route. The MFECD approach favors negatively charged IONPs that have low affinity for the brain endothelial cells and high colloidal stability. This suggests that MFECD may improve IONP-based drug delivery to the brain.

Fine-tuned bee-flower coevolutionary state hidden within multiple pollination interactions.

Relationships between flowers and pollinators are generally considered cases of mutualism since both agents gain benefits. Fine-tuned adaptations are usually found in the form of strict one-to-one coevolution between species. Many insect pollinators are, however, considered generalists, visiting numerous kinds of flowers, and many flower species (angiosperms) are also considered generalists, visited by many insect pollinators. We here describe a fine-tuned coevolutionary state of a flower-visiting bee that collects both nectar and pollen from an early spring flower visited by multiple pollinators. Detailed morphology of the bee proboscis is shown to be finely adjusted to the floral morphology and nectar production of the flower. Behavioral observations also confirm the precision of this mutualism. Our results suggest that a fine-tuned one-to-one coevolutionary state between a flower species and a pollinator species might be common, but frequently overlooked, in multiple flower-pollinator interactions.

A conceptual model of the role of complexity in the care of patients with multiple chronic conditions.

BACKGROUND: Effective healthcare for people with multiple chronic conditions (MCC) is a US priority, but the inherent complexity makes both research and delivery of care particularly challenging. As part of AHRQ Multiple Chronic Conditions Research Network (MCCRN) efforts, the Network developed a conceptual model to guide research in this area. OBJECTIVE: To synthesize methodological and topical issues relevant to MCC patient care into a framework that can improve the delivery of care and advance future research about caring for patients with MCC. METHODS: The Network synthesized essential constructs for MCC research identified from roundtable discussion, input from expert advisors, and previously published models. RESULTS: The AHRQ MCCRN conceptual model defines complexity as the gap between patient needs and healthcare services, taking into account both the multiple considerations that affect the needs of MCC patients, as well as the contextual factors that influence service delivery. The model reframes processes and outcomes to include not only clinical care quality and experience, but also patient health, well being, and quality of life. The single-condition paradigm for treating needs one-by-one falls apart and highlights the need for care systems to address dynamic patient needs. CONCLUSIONS: Defining complexity in terms of the misalignment between patient needs and services offers new insights in how to research and develop solutions to patient care needs.

Targeted drug delivery to intestinal macrophages by bioactive nanovesicles released from grapefruit.

The gut mucosal immune system is considered to play an important role in counteracting potential adverse effects of food-derived antigens including nanovesicles. Whether nanovesicles naturally released from edible fruit work in a coordinated manner with gut immune cells to maintain the gut in a noninflammatory status is not known. Here, as proof of concept, we demonstrate that grapefruit-derived nanovesicles (GDNs) are selectively taken up by intestinal macrophages and ameliorate dextran sulfate sodium (DSS)-induced mouse colitis. These effects were mediated by upregulating the expression of heme oxygenase-1 (HO-1) and inhibiting the production of IL-1ß and TNF-α in intestinal macrophages. The inherent biocompatibility and biodegradability, stability at wide ranges of pH values, and targeting of intestinal macrophages led us to further develop a novel GDN-based oral delivery system. Incorporating methotrexate (MTX), an anti-inflammatory drug, into GDNs and delivering the MTX-GDNs to mice significantly lowered the MTX toxicity when compared with free MTX, and remarkably increased its therapeutic effects in DSS-induced mouse colitis. These findings demonstrate that GDNs can serve as immune modulators in the intestine, maintain intestinal macrophage homeostasis, and can be developed for oral delivery of small molecule drugs to attenuate inflammatory responses in human disease.

Delivery of therapeutic agents by nanoparticles made of grapefruit-derived lipids.

Although the use of nanotechnology for the delivery of a wide range of medical treatments has potential to reduce adverse effects associated with drug therapy, tissue-specific delivery remains challenging. Here we show that nanoparticles made of grapefruit-derived lipids, which we call grapefruit-derived nanovectors, can deliver chemotherapeutic agents, short interfering RNA, DNA expression vectors and proteins to different types of cells. We demonstrate the in vivo targeting specificity of grapefruit-derived nanovectors by co-delivering therapeutic agents with folic acid, which in turn leads to significantly increasing targeting efficiency to cells expressing folate receptors. The therapeutic potential of grapefruit-derived nanovectors was further demonstrated by enhancing the chemotherapeutic inhibition of tumour growth in two tumour animal models. Grapefruit-derived nanovectors are less toxic than nanoparticles made of synthetic lipids and, when injected intravenously into pregnant mice, do not pass the placental barrier, suggesting that they may be a useful tool for drug delivery.

Tumor-associated primo vascular system is derived from xenograft, not host.

The primo vascular system (PVS), which is composed of very small primo-vessels (PV) and primo-nodes (PN), has recently emerged as a third component of circulatory system. Here, we report the presence of a tumor derived PVS in murine xenografts of human histiocytic lymphoma (U937) in close proximity to the tumor. Within this system, PNs are small (~500-600 µM diameter) membranous sac-like structures which contain numerous small cells which can be demonstrated by DAPI staining. Hematoxylin and Eosin (H&E) staining of the peri-tumoral PVS shows the presence of loose structures lined by fibroblasts but filled with dense fibers, cells, lacunae and nerve-like structures. The origin and type of cells within the PVS was characterized by immunostaining with antibodies for CD68, CD45 and lysozyme. The results of these studies reveal that the PVS of the xenograft originates from the human U937 tumor cells. qRT-PCR analysis of mRNA isolated from PVS cells reveals a striking predominance of human, rather than mouse, sequences. Of particular interest, human stem cell specific transcription factors were overexpressed, most notably KLF4, an upstream regulator of NANOG which maintains the pluripotent and undifferentiated state of stem cells. These results suggest that the cells present within the PVS are derived from the human xenograft and suggests that the primo-vessels associated with the xenografted tumor may provide a safe haven for a select population of cancer stem cells. Further understanding of the biological properties of these cells may allow the development of new anti-cancer interventions.