Enhancing oral delivery of plant-derived vesicles for colitis.

Plant-derived vesicles (PDVs) are attractive for therapeutic applications, including as potential nanocarriers. However, a concern with oral delivery of PDVs is whether they would remain intact in the gastrointestinal tract. We found that 82% of cabbage PDVs were destroyed under conditions mimicking the upper digestive tract. To overcome this limitation, we developed a delivery method whereby lyophilized Eudragit S100-coated cabbage PDVs were packaged into a capsule (Cap-cPDVs). Lyophilization and suspension of PDVs did not have an appreciable impact on PDV structure, number, or therapeutic effect. Additionally, packaging the lyophilized Eudragit S100-coated PDVs into capsules allowed them to pass through the upper gastrointestinal tract for delivery into the colon better than did suspension of PDVs in phosphate-buffered saline. Cap-cPDVs showed robust therapeutic effect in a dextran sulfate sodium-induced colitis mouse model. These findings could have broad implications for the use of PDVs as orally delivered nanocarriers of natural therapeutic plant compounds or other therapeutics.

Rules of engagement: Promoting academic-industry partnership in the era of digital pathology and artificial intelligence.

Academic industry partnership (AIP) represents an important alliance between academic researchers and industry that helps translate technology and complete the innovation cycle within academic health systems. Despite diverging missions and skillsets the culture for academia and industry is changing in response to the current digital era which is spawning greater collaboration between physicians and businesses in this marketplace. In the field of pathology, this is further driven by the fact that traditional funding sources cannot keep pace with the innovation needed in digital pathology and artificial intelligence. This concept article from the Digital Pathology Association (DPA) describes the rules of engagement for pathology innovators in academia and for their corporate partners to help establish best practices in this critical area. Stakeholders include pathologists, basic and translational researchers, university technology transfer and sponsored research offices, as well as industry relations officers. The article discusses the benefits and pitfalls of an AIP, reviews different partnership models, examines the role of pathologists in the innovation cycle, explains various agreements that may need to be signed, covers conflict of interest and intellectual property issues, and offers recommendations for ensuring successful partnerships.

Streptozotocin-induced hyperglycemia alters the cecal metabolome and exacerbates antibiotic-induced dysbiosis.

It is well established in the microbiome field that antibiotic (ATB) use and metabolic disease both impact the structure and function of the gut microbiome. But how host and microbial metabolism interacts with ATB susceptibility to affect the resulting dysbiosis remains poorly understood. In a streptozotocin-induced model of hyperglycemia (HG), we use a combined metagenomic, metatranscriptomic, and metabolomic approach to profile changes in microbiome taxonomic composition, transcriptional activity, and metabolite abundance both pre- and post-ATB challenge. We find that HG impacts both microbiome structure and metabolism, ultimately increasing susceptibility to amoxicillin. HG exacerbates drug-induced dysbiosis and increases both phosphotransferase system activity and energy catabolism compared to controls. Finally, HG and ATB co-treatment increases pathogen susceptibility and reduces survival in a Salmonella enterica infection model. Our data demonstrate that induced HG is sufficient to modify the cecal metabolite pool, worsen the severity of ATB dysbiosis, and decrease colonization resistance.

Report on computational assessment of Tumor Infiltrating Lymphocytes from the International Immuno-Oncology Biomarker Working Group.

Assessment of tumor-infiltrating lymphocytes (TILs) is increasingly recognized as an integral part of the prognostic workflow in triple-negative (TNBC) and HER2-positive breast cancer, as well as many other solid tumors. This recognition has come about thanks to standardized visual reporting guidelines, which helped to reduce inter-reader variability. Now, there are ripe opportunities to employ computational methods that extract spatio-morphologic predictive features, enabling computer-aided diagnostics. We detail the benefits of computational TILs assessment, the readiness of TILs scoring for computational assessment, and outline considerations for overcoming key barriers to clinical translation in this arena. Specifically, we discuss: 1. ensuring computational workflows closely capture visual guidelines and standards; 2. challenges and thoughts standards for assessment of algorithms including training, preanalytical, analytical, and clinical validation; 3. perspectives on how to realize the potential of machine learning models and to overcome the perceptual and practical limits of visual scoring.

Society of Toxicologic Pathology Digital Pathology and Image Analysis Special Interest Group Article*: Opinion on the Application of Artificial Intelligence and Machine Learning to Digital Toxicologic Pathology.

Toxicologic pathology is transitioning from analog to digital methods. This transition seems inevitable due to a host of ongoing social and medical technological forces. Of these, artificial intelligence (AI) and in particular machine learning (ML) are globally disruptive, rapidly growing sectors of technology whose impact on the long-established field of histopathology is quickly being realized. The development of increasing numbers of algorithms, peering ever deeper into the histopathological space, has demonstrated to the scientific community that AI pathology platforms are now poised to truly impact the future of precision and personalized medicine. However, as with all great technological advances, there are implementation and adoption challenges. This review aims to define common and relevant AI and ML terminology, describe data generation and interpretation, outline current and potential future business cases, discuss validation and regulatory hurdles, and most importantly, propose how overcoming the challenges of this burgeoning technology may shape toxicologic pathology for years to come, enabling pathologists to contribute even more effectively to answering scientific questions and solving global health issues. [Box: see text].

PPARD and Interferon Gamma Promote Transformation of Gastric Progenitor Cells and Tumorigenesis in Mice.

BACKGROUND & AIMS: The peroxisome proliferator-activated receptor delta (PPARD) regulates cell metabolism, proliferation, and inflammation and has been associated with gastric and other cancers. Villin-positive epithelial cells are a small population of quiescent gastric progenitor cells. We expressed PPARD from a villin promoter to investigate the role of these cells and PPARD in development of gastric cancer. METHODS: We analyzed gastric tissues from mice that express the Ppard (PPARD1 and PPARD2 mice) from a villin promoter, and mice that did not carry this transgene (controls), by histology and immunohistochemistry. We performed cell lineage-tracing experiments and analyzed the microbiomes, chemokine and cytokine production, and immune cells and transcriptomes of stomachs of these mice. We also performed immunohistochemical analysis of PPARD levels in 2 sets of human gastric tissue microarrays. RESULTS: Thirty-eight percent of PPARD mice developed spontaneous, invasive gastric adenocarcinomas, with severe chronic inflammation. Levels of PPARD were increased in human gastric cancer tissues, compared with nontumor tissues, and associated with gastric cancer stage and grade. We found an inverse correlation between level of PPARD in tumor tissue and patient survival time. Gastric microbiomes from PPARD and control mice did not differ significantly. Lineage-tracing experiments identified villin-expressing gastric progenitor cells (VGPCs) as the origin of gastric tumors in PPARD mice. In these mice, PPARD up-regulated CCL20 and CXCL1, which increased infiltration of the gastric mucosa by immune cells. Immune cell production of inflammatory cytokines promoted chronic gastric inflammation and expansion and transformation of VGPCs, leading to tumorigenesis. We identified a positive-feedback loop between PPARD and interferon gamma signaling that sustained gastric inflammation to induce VGPC transformation and gastric carcinogenesis. CONCLUSIONS: We found PPARD overexpression in VPGCs to result in inflammation, dysplasia, and tumor formation. PPARD and VGPCs might be therapeutic targets for stomach cancer.

Mouse Models of Overexpression Reveal Distinct Oncogenic Roles for Different Type I Protein Arginine Methyltransferases.

Protein arginine methyltransferases (PRMT) are generally not mutated in diseased states, but they are overexpressed in a number of cancers, including breast cancer. To address the possible roles of PRMT overexpression in mammary gland tumorigenesis, we generated Cre-activated PRMT1, CARM1, and PRMT6 overexpression mouse models. These three enzymes are the primary type I PRMTs and are responsible for the majority of the asymmetric arginine methylation deposited in the cells. Using either a keratin 5-Cre recombinase (K5-Cre) cross or an MMTV-NIC mouse, we investigated the impact of PRMT overexpression alone or in the context of a HER2-driven model of breast cancer, respectively. The overexpression of all three PRMTs induced hyper-branching of the mammary glands and increased Ki-67 staining. When combined with the MMTV-NIC model, these in vivo experiments provided the first genetic evidence implicating elevated levels of these three PRMTs in mammary gland tumorigenesis, albeit with variable degrees of tumor promotion and latency. In addition, these mouse models provided valuable tools for exploring the biological roles and molecular mechanisms of PRMT overexpression in the mammary gland. For example, transcriptome analysis of purified mammary epithelial cells isolated from bigenic NIC-PRMT1 Tg and NIC-PRMT6 Tg mice revealed a deregulated PI3K-AKT pathway. In the future, these PRMT Tg lines can be leveraged to investigate the roles of arginine methylation in other tissues and tumor model systems using different tissue-specific Cre crosses, and they can also be used for testing the in vivo efficacy of small molecule inhibitors that target these PRMT. SIGNIFICANCE: These findings establish Cre-activated mouse models of three different arginine methyltransferases, PRMT1, CARM1, and PRMT6, which are overexpressed in human cancers, providing a valuable tool for the study of PRMT function in tumorigenesis.See related commentary by Watson and Bitler, p. 3.

Activation of 4-1BB on Liver Myeloid Cells Triggers Hepatitis via an Interleukin-27-Dependent Pathway.

Purpose: Agonist antibodies targeting the T-cell costimulatory receptor 4-1BB (CD137) are among the most effective immunotherapeutic agents across preclinical cancer models. In the clinic, however, development of these agents has been hampered by dose-limiting liver toxicity. Lack of knowledge of the mechanisms underlying this toxicity has limited the potential to separate 4-1BB agonist-driven tumor immunity from hepatotoxicity.Experimental Design: The capacity of 4-1BB agonist antibodies to induce liver toxicity was investigated in immunocompetent mice, with or without coadministration of checkpoint blockade, via (i) measurement of serum transaminase levels, (ii) imaging of liver immune infiltrates, and (iii) qualitative and quantitative assessment of liver myeloid and T cells via flow cytometry. Knockout mice were used to clarify the contribution of specific cell subsets, cytokines, and chemokines.Results: We find that activation of 4-1BB on liver myeloid cells is essential to initiate hepatitis. Once activated, these cells produce interleukin-27 that is required for liver toxicity. CD8 T cells infiltrate the liver in response to this myeloid activation and mediate tissue damage, triggering transaminase elevation. FoxP3+ regulatory T cells limit liver damage, and their removal dramatically exacerbates 4-1BB agonist-induced hepatitis. Coadministration of CTLA-4 blockade ameliorates transaminase elevation, whereas PD-1 blockade exacerbates it. Loss of the chemokine receptor CCR2 blocks 4-1BB agonist hepatitis without diminishing tumor-specific immunity against B16 melanoma.Conclusions: 4-1BB agonist antibodies trigger hepatitis via activation and expansion of interleukin-27-producing liver Kupffer cells and monocytes. Coadministration of CTLA-4 and/or CCR2 blockade may minimize hepatitis, but yield equal or greater antitumor immunity. Clin Cancer Res; 24(5); 1138-51. ©2018 AACR.

Suspected systemic calcinosis and calciphylaxis in 5 horses.

Five horses were presented with signs of myopathy along with systemic malaise, hyperfibrinogenemia, hyperphosphatemia, and an elevated calcium phosphorus product (Ca*P). Postmortem findings were consistent with systemic calcinosis, a syndrome of calcium deposition in the tissue of organs including lungs, kidneys, muscle, and heart that has not been previously described in horses.

Stillborn infant with calcified chorionic epithelium, corneal scarring, and pericarditis.

This autopsy of a stillborn term infant revealed a constellation of unusual features including calcification of the chorion membrane and portions of the umbilical vascular media, extensive white matter gliosis, arthrogryposis multiplex congenita, adhesions of one eyelid to the globe, pericarditis, a miniature left foot, and a cleft palate. We hypothesized that the membrane and umbilical cord lesions resulted from an episode of resolved chorioamnionitis earlier in the pregnancy. Mare reproductive loss syndrome (MRLS) demonstrates a bacteremic infection of the amniotic cavity, pericarditis, and uniocular endophthalmitis in the mare. On the basis of analogy, we speculated that this infant suffered an intrauterine bacteremia with tissue predilection similar to that of MRLS.

Microbiologic and pathologic findings in an epidemic of equine pericarditis.

During the spring and summer of 2001 and in association with the mare reproductive loss syndrome, 22 terminal and 12 clinical cases of equine pericarditis were diagnosed in central Kentucky. Actinobacillus species were the principal isolates from 8 of 10 nontreated, terminally affected and 3 of 10 clinically affected horses. Enterococcus faecalis and Streptococcus zooepidemicus were cultured from the remaining 2 nontreated terminal cases. No viruses were isolated in tissue culture. Nucleic acid of equine herpesvirus-2 was detected in pericardial and tracheal wash fluids of 3 and 1 individuals, respectively. Microscopic alterations in sections of heart and parietal pericardium were consistent with chronic fibrinous bacterial pericarditis. This report confirms a significant role of Actinobacillus species in equine pericarditis and describes an epidemic of this infrequently observed syndrome in the horse.

Equine abortion and premature birth associated with Cellulosimicrobium cellulans infection.

During the 2002 and 2003 foaling seasons, Cellulosimicrobium (Cellumonas) cellulans (formerly Oerskovia xanthineolytica) was the principal microorganism isolated from fetal tissues or placentas from cases of equine abortion, premature birth, and term pregnancies. Significant pathologic findings included chronic placentitis and pyogranulomatous pneumonia. In addition, microscopic and macroscopic alterations in the allantochorion from 4 of 7 cases of placentitis were similar to those caused by Crossiella equi and other nocardioform bacteria. This report confirms a causative role of C. cellulans infection in equine abortion.

The toxicokinetics of cyanide and mandelonitrile in the horse and their relevance to the mare reproductive loss syndrome.

The epidemiological association between black cherry trees and mare reproductive loss syndrome has focused attention on cyanide and environmental cyanogens. This article describes the toxicokinetics of cyanide in horses and the relationships between blood cyanide concentrations and potentially adverse responses to cyanide. To identify safe and humane blood concentration limits for cyanide experiments, mares were infused with increasing doses (1-12 mg/min) of sodium cyanide for 1 h. Infusion at 12 mg/min produced clinical signs of cyanide toxicity at 38 min; these signs included increased heart rate, weakness, lack of coordination, loss of muscle tone, and respiratory and behavioral distress. Peak blood cyanide concentrations were about 2500 ng/mL; the clinical and biochemical signs of distress reversed when infusion stopped. Four horses were infused with 1 mg/min of sodium cyanide for 1 h to evaluate the distribution and elimination kinetics of cyanide. Blood cyanide concentrations peaked at 1160 ng/mL and then declined rapidly, suggesting a two-compartment, open model. The distribution (alpha) phase half-life was 0.74 h, the terminal (beta phase) half-life was 16.16 h. The mean residence time was 12.4 h, the steady-state volume of distribution was 2.21 L/kg, and the mean systemic clearance was 0.182 L/h/kg. Partitioning studies showed that blood cyanide was about 98.5% associated with the red cell fraction. No clinical signs of cyanide intoxication or distress were observed during these infusion experiments. Mandelonitrile was next administered orally at 3 mg/kg to four horses. Cyanide was rapidly available from the orally administered mandelonitrile and the C max blood concentration of 1857 ng/mL was observed at 3 min after dosing; thereafter, blood cyanide again declined rapidly, reaching 100 ng/mL by 4 h postadministration. The mean oral bioavailability of cyanide from mandelonitrile was 57% +/- 6.5 (SEM), and its apparent terminal half-life was 13 h +/- 3 (SEM). No clinical signs of cyanide intoxication or distress were observed during these experiments. These data show that during acute exposure to higher doses of cyanide (~600 mg/horse; 2500 ng/mL of cyanide in blood), redistribution of cyanide rapidly terminated the acute toxic responses. Similarly, mandelonitrile rapidly delivered its cyanide content, and acute cyanide intoxications following mandelonitrile administration can also be terminated by redistribution. Rapid termination of cyanide intoxication by redistribution is consistent with and explains many of the clinical and biochemical characteristics of acute, high-dose cyanide toxicity. On the other hand, at lower concentrations (<100 ng/mL in blood), metabolic transformation of cyanide is likely the dominant mechanism of termination of action. This process is slow, with terminal half-lives ranging from 12-16 hours. The large volume of distribution and the long terminal-phase-elimination half-life of cyanide suggest different mechanisms for toxicities and termination of toxicities associated with low-level exposure to cyanide. If environmental exposure to cyanide is a factor in the cause of MRLS, then it is likely in the more subtle effects of low concentrations of cyanide on specific metabolic processes that the associations will be found.