Characterizing the distributions of IDO-1 expressing macrophages/microglia in human and murine brains and evaluating the immunological and physiological roles of IDO-1 in RAW264.7/BV-2 cells

Indoleamine 2,3-dioxygenase 1 (IDO-1) is an immunosuppressive enzyme expressed in the placenta, neoplastic cells, and macrophages to reject T cells by converting tryptophan into kynurenine. However, the role of IDO-1 in brain immunity, especially in the meninges, is unclear. We aim to elucidate the distribution pattern of IDO-1+ macrophages/microglia in the human brain tissues, human glioblastoma, APP/PS1 mouse brains, and quinolinic acid model brains and explore the physiological and immunological roles of IDO-1+ macrophages/microglia. Here, we find that both human and mouse macrophages/microglia of the perivascular and subarachnoid space and in glioblastoma (GBM) expressed IDO-1 but not macrophages/microglia of parenchyma. Using IDO-1 inhibitors including 1-MT and INCB24360, we observed that inhibiting IDO-1 reduced the cellular size and filopodia growth, fluid uptake, and the macropinocytic and phagocytic abilities of human blood monocytes and RAW264.7/BV-2 cells. Inhibiting IDO-1 with 1-MT or INCB24360 increased IL-1β secretion and suppressed NLRP3 expression in RAW264.7/BV-2 cells. Our data collectively show that IDO-1 expression in perivascular and meninges macrophages/microglia increases cellular phagocytic capacity and might suppress overactivation of inflammatory reaction.

Cyperus rotundus root extract inhibits progress of lymphedema in mouse tail model

Lymphedema is clinically manifested as swelling due to abnormal accumulation of interstitial fluid attributed to inefficient fluid uptake and reduced lymphatic flow. Here we have evaluated the effect of Cyperus rotundus root (CRR) ethanolic extract in a mouse tail model of lymphedema and hypothesized that the Cyperus rotundus plant is known for its anti-inflammatory effect through inhibition of TNF alpha will be effective in managing this condition. The skin was removed was done after leaving 1cm of distance from the base of the trunk. The cut was introduced in a sterile condition. The animals were divided into Experimental control(EC) and Cyperus rotundus (CRR) treated groups. A change in tail volume around the wound was monitored for up to 20 days. The kinetics of the swelling was calculated for statistical significance. Further TS of the upper part of the wound was stained with H&E stain and documented for histological changes.RESULTS: In the EC group, a gradual rise in swelling was recorded, which peaked on the 10th day and continued up to the 15th day, followed by a gradual decrease. In CR extract-treated group, the swelling was significantly low and the peak was obtained on the 8th day, while in the EC group the swelling was significantly higher and the peak was obtained 11th day. The histological section show, fibrous band intersection the lobules of adipocyte and lymphatic vascular channel and muscles in the sub epithelium region in the EC group, which was very less in CRR group.

Bacterial detection by NAIP/NLRC4 elicits prompt contractions of intestinal epithelial cell layers

The gut epithelium serves to maximize the surface for nutrient and fluid uptake, but at the same time must provide a tight barrier to pathogens and remove damaged intestinal epithelial cells (IECs) without jeopardizing barrier integrity. How the epithelium coordinates these tasks remains a question of significant interest. We used imaging and an optical flow analysis pipeline to study the dynamicity of untransformed murine and human intestinal epithelia, cultured atop flexible hydrogel supports. Infection with the pathogen Salmonella Typhimurium (S.Tm) within minutes elicited focal contractions with inward movements of up to ∼1,000 IECs. Genetics approaches and chimeric epithelial monolayers revealed contractions to be triggered by the NAIP/NLRC4 inflammasome, which sensed type-III secretion system and flagellar ligands upon bacterial invasion, converting the local tissue into a contraction epicenter. Execution of the response required swift sublytic Gasdermin D pore formation, ion fluxes, and the propagation of a myosin contraction pulse across the tissue. Importantly, focal contractions preceded, and could be uncoupled from, the death and expulsion of infected IECs. In both two-dimensional monolayers and three-dimensional enteroids, multiple infection-elicited contractions coalesced to produce shrinkage of the epithelium as a whole. Monolayers deficient for Caspase-1(-11) or Gasdermin D failed to elicit focal contractions but were still capable of infected IEC death and expulsion. Strikingly, these monolayers lost their integrity to a markedly higher extent than wild-type counterparts. We propose that prompt NAIP/NLRC4/Caspase-1/Gasdermin D/myosin–dependent contractions allow the epithelium to densify its cell packing in infected regions, thereby preventing tissue disintegration due to the subsequent IEC death and expulsion process.

Fast laser surface texturing of spherical samples to improve the frictional performance of elasto-hydrodynamic lubricated contacts

Textured surfaces offer the potential to promote friction and wear reduction by increasing the hydrodynamic pressure, fluid uptake, or acting as oil or debris reservoirs. However, texturing techniques often require additional manufacturing steps and costs, thus frequently being not economically feasible for real engineering applications. This experimental study aims at applying a fast laser texturing technique on curved surfaces for obtaining superior tribological performances. A femtosecond pulsed laser (Ti:Sapphire) and direct laser interference patterning (with a solid-state Nd:YAG laser) were used for manufacturing dimple and groove patterns on curved steel surfaces (ball samples). Tribological tests were carried out under elasto-hydrodynamic lubricated contact conditions varying slide-roll ratio using a ball-on-disk configuration. Furthermore, a specific interferometry technique for rough surfaces was used to measure the film thickness of smooth and textured surfaces. Smooth steel samples were used to obtain data for the reference surface. The results showed that dimples promoted friction reduction (up to 20%) compared to the reference smooth specimens, whereas grooves generally caused less beneficial or detrimental effects. In addition, dimples promoted the formation of full film lubrication conditions at lower speeds. This study demonstrates how fast texturing techniques could potentially be used for improving the tribological performance of bearings as well as other mechanical components utilised in several engineering applications.

A Novel Approach to Negative Pressure Wound Therapy: Use of High Suction Capillary Device to Improve Wound Healing

ABSTRACT Introduction Negative Pressure Wound Therapy (NPWT) is a procedure used for nonhealing wounds. In NPWT, a special sealed dressing of large cell foam (>400 µm) or gauze is connected to a pump. Most commonly, negative pressures between −10 and −125 millimeters of mercury (mm Hg) are used. The mechanism of healing is unknown but maybe attributable to removal of the exudate and bacteria, and the stimulation of tissue repair through microdeformation. Reticulated foams with micron-size open cells, Capillary Suction Devices (CSD; 100 to 5 µm) exert capillary suction between 10 and 70 mm of Hg with a multilayered foam dressing. Materials and Methods Yorkshire pigs received 5 surgical excision wounds, 3 cm2, on each side of the back. The wounds were covered with a NPWT dressing (110 mm Hg negative pressure by a pump), CSD with capillary suctions of 30 mm Hg (CSD-30) and 70 mm Hg (CSD-70), and a conventional gauze dressing. The wounds were measured on day 2, and then every 4-5 days thereafter; the total fluid collected by the various dressing over time. Results By post-wound day 20, the wounds treated with CSD-70 and NPWT were 100% closed while the wounds treated with CSD-30 and gauze were 65% and 45%, respectively. This indicated comparable wound closure efficacies for CSD-70 and NPWT. The average total fluid uptake measured in grams dry weight were similar for CSD-70 and NPWT, 36 and 38 g, respectively, while the values were 24 g for CSD-30 and 12 g for gauze. However, the maximum fluid uptake observed at day 2 indicated that CSD-70 and CSD 30, 24 and 14 g, respectively, were superior to NPWT and gauze 12 and 7 g, respectively. Conclusion This data indicate comparable wound closure efficacies for CSD-70 and NPWT. It is felt that CSD is an effective, safe, and lower cost alternative to vacuum-assisted NPWT.

INCB24360 Suppresses M1-like Macrophage Formation and NLRP3 Expression Whereas Increases IL-1β Secretion in RAW264.7 and BV-2

Background: Macrophages switch between different functional phenotypes under the different physiological or path-physiological stimuli in tissue. Macrophage functional phenotype heavily affects disease progression, including inflammation, injury, neurodegenerative disease, and cancers. IDO-1, a druggable target, is an immunosuppressive enzyme expressed in tissue macrophages and induced by Interferon-γ (IFN-γ). How IDO-1 inhibitors affect the functional switches of macrophage are unknown. Methods: IFN-γ were used to increase IDO-1 expression and 1-Methyl-D-tryptophan (1-MT) and INCB24360 (Epacadostat) were used to inhibit IDO-1 activity in RAW264.7 and BV-2. Western blotting, immunostaining and ELISA were used to evaluate protein expressions or secretion. RT-PCR were used to assess to transcription. TMR-Dextran and Latex beads were used to test endocytic, macropinocytic and phagocytic ability of macrophage and Fiji image and IMARIS were used to analyze images.Results: Our results showed that INCB24360 preferentially suppresses the cellular size and filopodia growth and reduces fluid uptake, macropinocytosis, and phagocytic ability of IFN-γ induced or non-induced RAW264.7 and BV-2 in vitro. 1-MT and INCB24360 suppress IFN-γ induced or endogenous NLRP3 expression levels but not caspase-1 in RAW264.7 and BV-2. NLRP3 reduction induced by 1-MT and INCB24360 parallel with the decrease of NLRP3 gene transcription and an increase of IL-1β secretion. Conclusions: Our data collectively showed that inhibiting IDO-1 with its inhibitors, especially INCB24360, preferentially suppresses cellular size and filopodia growth, NLRP3 expression, the endocytic, macropinocytic, and phagocytic capacity whereas increases IL-1β secretion in macrophage. Our findings do not rule out the roles of IDO-1 in the formation of M1-like macrophages, but they cast doubt on the robust anti-inflammatory effects of IDO inhibitors in the macrophage-mediated immune response.

653 Capillary Suction Device-a Novel Approach to Negative Pressure Wound Therapy

Introduction Negative Pressure Wound Therapy (NPWT) is a well-established procedure used for non-healing wounds including burn wounds. In NPWT, a special sealed dressing of large cell foam (>400 µm) or gauze is connected to a pump. The sealed dressing acts as a conduit to pressure transfer and aids in the passive flow of fluid. Most commonly, negative pressures between -10 and -125 millimeters of mercury (mm Hg) are used. The mechanism of healing is unknown but maybe due to removal of the exudate and bacteria, and the stimulation of tissue repair through micro deformation. Reticulated foams with micron-size open cells (100 to 5µm) exerts capillary suction between 10 and 60 mm of Hg with a multilayered foam dressing. The negative pressures produced are within the range of suction by mechanical pumps. Therefore, the long-term goal our research is to examine effectiveness of Capillary Suction Devices (CSD) as a topical device in both preventing and healing complicated wounds, burn and donor site wounds. Our hypothesis is that CSD is an effective, safe and lower cost alternative to vacuum-assisted NPWT. Methods Yorkshire pigs received 4 surgical posterior excision wounds, measuring 2 in. by 2 in. The wounds were covered with a NPWT dressing (110 mm Hg negative pressure by a pump), CSD with capillary suctions of 30 mm Hg (CSD-30) and 60+ mm Hg (CSD-60), and a conventional gauze dressing. The wounds were measured on 2 day and then every 4 to 5 days until wounds closed. We also measured and compared the total fluids collected with each dressing. Results By post-wound day 20, the wounds treated with CSD-60 and NPWT were 100% closed while the wounds treated with CSD-30 and gauze were 65 and 45%, respectively. This indicated comparable wound closure efficacies for CSD-60 and NPWT. The CSD-30 product was superior to gauze, but less efficacious than the tested NPWT protocol. The average total fluid uptake measured in grams dry weight were similar for CSD-60 and NPWT, 36 and 38g., respectively while the values were 24g for CSD-30 and 12g for gauze. However, the maximum fluid uptake observed at day 2 indicated that CSD-60 and CSD 30, 24 and 14g respectively, were superior to NPWT and gauze 12 and 7g respectively. Conclusions This data indicates comparable wound closure efficacies for CSD-60 capillary suction and NPWT. The CSD product with 30 mmHg suction was superior to gauze, but less efficacious than NPWT or CSD-60 protocol. The study results provide impetus for further research on the use of high suction CSD for replacement of pump mediated NPWT and the moderate suction CSD for preventing progression of high-risk wounds to an ulcerous stage. Applicability of Research to Practice This small study suggests that CSD maybe alternative in to NPWT. CSD provides a significant cost and weight advantage to the patient, as well is allowing for increased mobility.