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Implantable medical devices have revolutionized modern medicine. However, immune-mediated foreign body response (FBR) to the materials of these devices can limit their function or even induce failure. Here we describe long-term controlled-release formulations for local anti-inflammatory release through the development of compact, solvent-free crystals. The compact lattice structure of these crystals allows for very slow, surface dissolution and high drug density. These formulations suppress FBR in both rodents and non-human primates for at least 1.3 years and 6 months, respectively. Formulations inhibited fibrosis across multiple implant sites—subcutaneous, intraperitoneal and intramuscular. In particular, incorporation of GW2580, a colony stimulating factor 1 receptor inhibitor, into a range of devices, including human islet microencapsulation systems, electrode-based continuous glucose-sensing monitors and muscle-stimulating devices, inhibits fibrosis, thereby allowing for extended function. We believe that local, long-term controlled release with the crystal formulations described here enhances and extends function in a range of medical devices and provides a generalized solution to the local immune response to implanted biomaterials. Foreign body response can result in failure of biomaterials in vivo. Solvent-free crystals containing anti-fibrotic drugs now show the potential for long-term inhibition of fibrosis on a number of implantable devices in rodents and non-human primates.

Host recognition and immune-mediated foreign body response to biomaterials can compromise the performance of implanted medical devices. To identify key cell and cytokine targets, here we perform in-depth systems analysis of innate and adaptive immune system responses to implanted biomaterials in rodents and non-human primates. While macrophages are indispensable to the fibrotic cascade, surprisingly neutrophils and complement are not. Macrophages, via CXCL13, lead to downstream B cell recruitment, which further potentiated fibrosis, as confirmed by B cell knockout and CXCL13 neutralization. Interestingly, colony stimulating factor-1 receptor (CSF1R) is significantly increased following implantation of multiple biomaterial classes: ceramic, polymer and hydrogel. Its inhibition, like macrophage depletion, leads to complete loss of fibrosis, but spares other macrophage functions such as wound healing, reactive oxygen species production and phagocytosis. Our results indicate that targeting CSF1R may allow for a more selective method of fibrosis inhibition, and improve biomaterial biocompatibility without the need for broad immunosuppression. By studying the immune responses of animals to different types of biomaterial implants, colony stimulating factor-1 receptor is revealed as an important mediator of the foreign body reaction and a possible target for fibrosis inhibition.

Continuous glucose monitors (CGMs), used by patients with diabetes mellitus, can autonomously track fluctuations in blood glucose over time. However, the signal produced by CGMs during the initial recording period following sensor implantation contains substantial noise, requiring frequent recalibration via fingerprick tests. Here, we show that coating the sensor with a zwitterionic polymer, found via a combinatorial-chemistry approach, significantly reduces signal noise and improves CGM performance. We evaluated the polymer-coated sensors in mice as well as in healthy and diabetic non-human primates, and show that the sensors accurately record glucose levels without the need for recalibration. We also show that the polymer-coated sensors significantly abrogated immune responses to the sensor, as indicated by histology, fluorescent whole-body imaging of inflammation-associated protease activity, and gene expression of inflammation markers. The polymer coating may allow CGMs to become standalone measuring devices.

Background: Statin use is associated with a decreased rate of severe sepsis. The objective of this paper is to quantify the level of organ dysfunction of patients with and without statin use prior to hospitalization. Methods: MIMIC-III was searched for adult sepsis patients. Immunosuppressed patients were excluded. Organ dysfunction was defined as alterations in Sequential Organ Failure Assessment (SOFA) score components or laboratory values. Other endpoints examined include 28-day, 90-day, and in-hospital mortality. All analyses were adjusted for Elixhauser comorbidity index components, age, gender, ethnicity, and year of admission and used doubly robust estimation. In a sensitivity analysis, the effect of statin potency on organ dysfunction was analyzed. Findings: 3,091 statin users and non-users were matched. In the matched cohort, mean age was 72 years, 54% of patients were female, and 31% had diabetes. The odds of mortality at day 28 (0.78), day 90 (0.75), and in the hospital (0.78) were significantly lower for those on statins (p=0.001; p

Natural infections expose the immune system to escalating antigen and inflammation over days to weeks, whereas nonlive vaccines are single bolus events. We explored whether the immune system responds optimally to antigen kinetics most similar to replicating infections, rather than a bolus dose. Using HIV antigens, we found that administering a given total dose of antigen and adjuvant over 1–2 wk through repeated injections or osmotic pumps enhanced humoral responses, with exponentially increasing (exp-inc) dosing profiles eliciting >10-fold increases in antibody production relative to bolus vaccination post prime. Computational modeling of the germinal center response suggested that antigen availability as higher-affinity antibodies evolve enhances antigen capture in lymph nodes. Consistent with these predictions, we found that exp-inc dosing led to prolonged antigen retention in lymph nodes and increased Tfh cell and germinal center B-cell numbers. Thus, regulating the antigen and adjuvant kinetics may enable increased vaccine potency.

The transplantation of glucose-responsive, insulin-producing cells offers the potential for restoring glycemic control in individuals with diabetes. Pancreas transplantation and the infusion of cadaveric islets are currently implemented clinically, but these approaches are limited by the adverse effects of immunosuppressive therapy over the lifetime of the recipient and the limited supply of donor tissue. The latter concern may be addressed by recently described glucose-responsive mature beta cells that are derived from human embryonic stem cells (referred to as SC-β cells), which may represent an unlimited source of human cells for pancreas replacement therapy. Strategies to address the immunosuppression concerns include immunoisolation of insulin-producing cells with porous biomaterials that function as an immune barrier. However, clinical implementation has been challenging because of host immune responses to the implant materials. Here we report the first long-term glycemic correction of a diabetic, immunocompetent animal model using human SC-β cells. SC-β cells were encapsulated with alginate derivatives capable of mitigating foreign-body responses in vivo and implanted into the intraperitoneal space of C57BL/6J mice treated with streptozotocin, which is an animal model for chemically induced type 1 diabetes. These implants induced glycemic correction without any immunosuppression until their removal at 174 d after implantation. Human C-peptide concentrations and in vivo glucose responsiveness demonstrated therapeutically relevant glycemic control. Implants retrieved after 174 d contained viable insulin-producing cells.

BackgroundGiven the protracted nature of the crisis in Syria, the large noncommunicable disease (NCD) caseload of Syrian refugees and host Lebanese, and the high costs of providing NCD care, the implications for Lebanon’s health system are vast. ObjectiveThe aim of this study was to evaluate the effectiveness of treatment guidelines and a mobile health (mHealth) app on quality of care and health outcomes in primary care settings in Lebanon. MethodsA longitudinal cohort study was implemented from January 2015 to August 2016 to evaluate the effectiveness of treatment guidelines and an mHealth app on quality of care and health outcomes for Syrian and Lebanese patients in Lebanese primary health care (PHC) facilities. ResultsCompared with baseline record extraction, recording of blood pressure (BP) readings (−11.4%, P

The foreign body response is an immune-mediated reaction that can lead to the failure of implanted medical devices and discomfort for the recipient. There is a critical need for biomaterials that overcome this key challenge in the development of medical devices. Here we use a combinatorial approach for covalent chemical modification to generate a large library of variants of one of the most widely used hydrogel biomaterials, alginate. We evaluated the materials in vivo and identified three triazole-containing analogs that substantially reduce foreign body reactions in both rodents and, for at least 6 months, in non-human primates. The distribution of the triazole modification creates a unique hydrogel surface that inhibits recognition by macrophages and fibrous deposition. In addition to the utility of the compounds reported here, our approach may enable the discovery of other materials that mitigate the foreign body response.

Klebsiella pneumoniae is a bacterial pathogen of worldwide importance and a significant contributor to multiple disease presentations associated with both nosocomial and community acquired disease. ATCC 43816 is a well-studied K. pneumoniae strain which is capable of causing an acute respiratory disease in surrogate animal models. In this study, we performed sequencing of the ATCC 43816 genome to support future efforts characterizing genetic elements required for disease. Furthermore, we performed comparative genetic analyses to the previously sequenced genomes from NTUH-K2044 and MGH 78578 to gain an understanding of the conservation of known virulence determinants amongst the three strains. We found that ATCC 43816 and NTUH-K2044 both possess the known virulence determinant for yersiniabactin, as well as a Type 4 secretion system (T4SS), CRISPR system, and an acetonin catabolism locus, all absent from MGH 78578. While both NTUH-K2044 and MGH 78578 are clinical isolates, little is known about the disease potential of these strains in cell culture and animal models. Thus, we also performed functional analyses in the murine macrophage cell lines RAW264.7 and J774A.1 and found that MGH 78578 (K52 serotype) was internalized at higher levels than ATCC 43816 (K2) and NTUH-K2044 (K1), consistent with previous characterization of the antiphagocytic properties of K1 and K2 serotype capsules. We also examined the three K. pneumoniae strains in a novel BALB/c respiratory disease model and found that ATCC 43816 and NTUH-K2044 are highly virulent (LD[subscript 50], University of Louisville

The foreign body response is an immune-mediated reaction that can lead to the failure of implanted medical devices and discomfort for the recipient1–6. There is a critical need for biomaterials that overcome this key challenge in the development of medical devices. Here we use a combinatorial approach for covalent chemical modification to generate a large library of variants of one of the most widely used hydrogel biomaterials, alginate. We evaluated the materials in vivo and identified three triazole-containing analogs that substantially reduce foreign body reactions in both rodents and, for at least 6 months, in non-human primates. The distribution of the triazole modification creates a unique hydrogel surface that inhibits recognition by macrophages and fibrous deposition. In addition to the utility of the compounds reported here, our approach may enable the discovery of other materials that mitigate the foreign body response.

Nat. Med.; doi:10.1038/nm.4030; corrected online 18 February 2016 In the version of this article initially published online, the authors omitted acknowledgment recognizing the histology core of the Harvard Stem Cell Institute and several individuals for their assistance. The error has been correctedfor the print, PDF and HTML versions of this article.

The outcome of older (≥ 60 years) acute myeloid leukemia (AML) patients is poor, and novel treatments are needed. In a phase 2 trial for older AML patients, low-dose (20 mg/m2 per day for 10 days) decitabine, a DNA hypomethylating azanucleoside, produced 47% complete response rate with an excellent toxicity profile. To assess the genome-wide activity of decitabine, we profiled pretreatment and post treatment (day 25/course 1) methylomes of marrow samples from patients (n = 16) participating in the trial using deep-sequencing analysis of methylated DNA captured by methyl-binding protein (MBD2). Decitabine significantly reduced global methylation compared with pretreatment baseline (P = .001). Percent marrow blasts did not correlate with global methylation levels, suggesting that hypomethylation was related to the activity of decitabine rather than to a mere decrease in leukemia burden. Hypomethylation occurred predominantly in CpG islands and CpG island-associated regions (P ranged from .03 to .04) A significant concentration (P < .001) of the hypomehtylated CpG islands was found in chromosome subtelomeric regions, suggesting a differential activity of decitabine in distinct chromosome regions. Hypermethylation occurred much less frequently than hypomethylation and was associated with low CpG content regions. Decitabine-related methylation changes were concordant with those previously reported in distinct genes. In summary, our study supports the feasibility of methylome analyses as a pharmacodynamic endpoint for hypomethylating therapies.

Advances in whole genome profiling have revolutionized the cancer research field, but at the same time have raised new bioinformatics challenges. For next generation sequencing (NGS), these include data storage, computational costs, sequence processing and alignment, delineating appropriate statistical measures, and data visualization. The NGS application MethylCap-seq involves the in vitro capture of methylated DNA and subsequent analysis of enriched fragments by massively parallel sequencing. Here, we present a scalable, flexible workflow for MethylCap-seq Quality Control, secondary data analysis, tertiary analysis of multiple experimental groups, and data visualization. This workflow and its suite of features will assist biologists in conducting methylation profiling projects and facilitate meaningful biological interpretation.

Coordination state probabilities for the [Zn(H(2)O)(n)(CH(3)OH)(m)](2+) complex in aqueous methanol solutions are calculated as a function of the bulk solution concentration, and the number of methanol ligands, m = 0, 1, ..., 6 with n+m = 6. Zinc ion solvation free energies, which serve to normalize these probabilities, also reproduce the methanol concentration dependence of the experimentally derived free energy of zinc ion transfer from water to aqueous methanol solutions. Coordination state probabilities, p(n, m), are derived by extending quasi-chemical theory of ion hydration to solvent mixtures and mixed ligands. Free energy contributions to p(n, m) include the free energy of forming the mixed-ligand complex in the ideal gas, obtained by quantum chemical calculations, and the solvation free energy of the complex, approximated by a dielectric continuum model. We find that replacing water ligands with methanol ligands preferentially stabilizes methanol-rich complexes in the ideal gas. Conversely, water-rich complexes are stabilized by the solvation free energy contribution, such that the [Zn(H(2)O)(6)](2+) complex is the dominant species in solution for all methanol concentrations considered. Stabilization of the methanol-rich complexes is a consequence of the local coordination chemistry, dominated by the delocalization of charge on the zinc ion, while the stabilization of water-rich complexes is a consequence of favorable ion-solvent electrostatic interactions and smaller dielectric cavities for the water-rich complexes at fixed total charge in the dielectric continuum model. Our analysis also highlights an entropic contribution associated with the reversible work required to remove n water and m methanol molecules from bulk solution to form the [Zn(H(2)O)(n)(CH(3)OH)(m)](2+) complex, which captures the methanol concentration dependence of the solvation free energy of the zinc ion.

Background Advances in whole genome profiling have revolutionized the cancer research field, but at the same time have raised new bioinformatics challenges. For next generation sequencing (NGS), these include data storage, computational costs, sequence processing and alignment, delineating appropriate statistical measures, and data visualization. Currently there is a lack of workflows for efficient analysis of large, MethylCap-seq datasets containing multiple sample groups. Methods The NGS application MethylCap-seq involves the in vitro capture of methylated DNA and subsequent analysis of enriched fragments by massively parallel sequencing. The workflow we describe performs MethylCap-seq experimental Quality Control (QC), sequence file processing and alignment, differential methylation analysis of multiple biological groups, hierarchical clustering, assessment of genome-wide methylation patterns, and preparation of files for data visualization. Results Here, we present a scalable, flexible workflow for MethylCap-seq QC, secondary data analysis, tertiary analysis of multiple experimental groups, and data visualization. We demonstrate the experimental QC procedure with results from a large ovarian cancer study dataset and propose parameters which can identify problematic experiments. Promoter methylation profiling and hierarchical clustering analyses are demonstrated for four groups of acute myeloid leukemia (AML) patients. We propose a Global Methylation Indicator (GMI) function to assess genome-wide changes in methylation patterns between experimental groups. We also show how the workflow facilitates data visualization in a web browser with the application Anno-J. Conclusions This workflow and its suite of features will assist biologists in conducting methylation profiling projects and facilitate meaningful biological interpretation.