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Intestinal disequilibrium leads to inflammatory bowel disease (IBD), and chronic inflammation predisposes to oncogenesis. Antigen-presenting dendritic cells (DCs) and macrophages can tip the equilibrium toward tolerance or pathology. Here we show that delta-9-tetrahydrocannabinol (THC) attenuates colitis-associated colon cancer and colitis induced by anti-CD40. Working through cannabinoid receptor 2 (CB2), THC increases CD103 expression on DCs and macrophages and upregulates TGF-β1 to increase T regulatory cells (Tregs). THC-induced Tregs are necessary to remedy systemic IFNγ and TNFα caused by anti-CD40, but CB2-mediated suppression of APCs by THC quenches pathogenic release of IL-22 and IL-17A in the colon. By examining tissues from multiple sites, we confirmed that THC affects DCs, especially in mucosal barrier sites in the colon and lungs, to reduce DC CD86. Using models of colitis and systemic inflammation we show that THC, through CB2, is a potent suppressor of aberrant immune responses by provoking coordination between APCs and Tregs., Competing Interests: The authors have declared that no conflicts of interest exist., (© 2020 The Authors.)

Although previous reports suggest that tumor-induced myeloid-derived suppressor cells (MDSC) inhibit T cells by L-arginine depletion through arginase-1 activity, we herein show that arginase-1 is neither inherently expressed in MDSC nor required for MDSC-mediated inhibition. Employing Percoll density gradients, large expansions of MDSC in the bone marrow of tumor-bearing mice were isolated and demonstrated potent inhibition in T-cell proliferation activated by TCR-ligation, Concanavalin A, PMA plus ionomycin, or IL-2. Despite demonstrating characteristic immunosuppressive capacity, these MDSC exhibit no arginase-1 expression and/or exert their inhibitory effects independent of arginase-1 activity. However, arginase-1 expression in MDSC can be induced by exposure to TCR-activated T cells or their culture medium, but not T cells activated by other means or growing tumor cells. Further investigation reveals multiple cytokines secreted by TCR-activated T cells as orchestrating two signaling-relay axes, IL-6-to-IL-4 and GM-CSF/IL-4-to-IL-10, leading to arginase-1 expression in MDSC. Specifically, IL-6 signaling increases IL-4R, enabling IL-4 to induce arginase-1 expression; similarly, GM-CSF in concert with IL-4 induces IL-10R, allowing IL-10-mediated induction. Surprisingly, our study indicates that induction of arginase-1 expression is not conducive to the critical MDSC-mediated inhibition toward T cells, which is rather dependent on direct cell contacts undiminished by PD-L1 blockade or SIRPα deficiency., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Myeloid-derived suppressor cells (MDSCs) promote tumor growth through, in part, inhibiting T-cell immunity. However, mechanisms underlying MDSC expansion and guidance of MDSCs toward the tumor microenvironment remain unclear. Employing Percoll density gradients, we separate bone marrow (BM) leukocytes from tumor-bearing mice into four density-increasing bands with myeloid leukocytes enriched in bands III and IV. Band III comprises monocytes and low-density granulocytes, both confirmed to be M-MDSCs and G-MDSCs, respectively, by displaying potent inhibition of T-cell proliferation. However, monocytes act as M-MDSCs not only under tumor conditions but also the healthy condition. In contrast, band IV contains non-inhibitory, mature granulocytes. Only band III G-MDSCs display significant expansion in mice bearing B16 melanoma, Lewis lung carcinoma, or MC38 colon carcinoma. The expanded G-MDSCs also show increased CXCR2 expression, which guides egress out of BM, and produce arginase-1 and ROS upon encountering antigen-activated T cells. Adoptive transfer assays demonstrate that both G-MDSCs and mature granulocytes infiltrate tumors, but only the former displays sustention and accumulation. Intratumoral administrations of granulocytes further demonstrate that G-MDSCs promote tumor growth, whereas mature granulocytes exert minimal effects, or execute powerful anti-tumor effects providing the presence of PMN activation mechanisms in the tumor microenvironment., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: Growth and nutrition are critical in neonatal care. Whether feeding guidelines improve growth and nutrition and reduce morbidity is unknown., Purpose: Feeding guidelines for very low birth-weight (VLBW) infants were implemented in our neonatal intensive care unit (NICU) to start and achieve full enteral feeds sooner, and increase weight gain over the first month., Methods: Feeding guidelines for VLBW infants were implemented in January 2014, stratified by birth weight (<750, 750-1000, and 1000-1500 g). After trophic feedings, enteral feedings were advanced by 20 to 30 mL/kg/d.Data were analyzed for 2 years prior (baseline) and 6 months after (guideline) guidelines were implemented and included days to initiation of enteral feeds, days on total parenteral nutrition (TPN), and weight gain over the first month. Potential concomitant factors that could affect feeding tolerance were examined including indomethacin or dopamine treatment, delivery room cardiopulmonary resuscitation, and growth restriction., Results: A total of 95 infants with a birth weight of less than 1500 g were included (59 baseline and 36 guideline). Days to start enteral feeds decreased by 47% (P < .01) and days on TPN decreased by 25% (16 days vs 11 days; P < .01). Weight gain over the first month of life increased by 15% (p < .05). Dopamine and indomethacin use decreased during the study period, and small for gestational age infants were overrepresented in the guideline group., Implications for Practice/research: Establishment of feeding guidelines for VLBW infants in our NICU reduced the days to start feeds and days on TPN while increasing weight gain over the first month. Improving growth and nutrition and reducing need for TPN in this vulnerable population may ultimately prevent infection and improve neurodevelopmental outcomes.

Rapid clearance of adoptively transferred Cd47-null (Cd47(-/-)) cells in congeneic WT mice suggests a critical self-recognition mechanism, in which CD47 is the ubiquitous marker of self, and its interaction with macrophage signal regulatory protein α (SIRPα) triggers inhibitory signaling through SIRPα cytoplasmic immunoreceptor tyrosine-based inhibition motifs and tyrosine phosphatase SHP-1/2. However, instead of displaying self-destruction phenotypes, Cd47(-/-) mice manifest no, or only mild, macrophage phagocytosis toward self-cells except under the nonobese diabetic background. Studying our recently established Sirpα-KO (Sirpα(-/-)) mice, as well as Cd47(-/-) mice, we reveal additional activation and inhibitory mechanisms besides the CD47-SIRPα axis dominantly controlling macrophage behavior. Sirpα(-/-) mice and Cd47(-/-) mice, although being normally healthy, develop severe anemia and splenomegaly under chronic colitis, peritonitis, cytokine treatments, and CFA-/LPS-induced inflammation, owing to splenic macrophages phagocytizing self-red blood cells. Ex vivo phagocytosis assays confirmed general inactivity of macrophages from Sirpα(-/-) or Cd47(-/-) mice toward healthy self-cells, whereas they aggressively attack toward bacteria, zymosan, apoptotic, and immune complex-bound cells; however, treating these macrophages with IL-17, LPS, IL-6, IL-1β, and TNFα, but not IFNγ, dramatically initiates potent phagocytosis toward self-cells, for which only the Cd47-Sirpα interaction restrains. Even for macrophages from WT mice, phagocytosis toward Cd47(-/-) cells does not occur without phagocytic activation. Mechanistic studies suggest a PKC-Syk-mediated signaling pathway, to which IL-10 conversely inhibits, is required for activating macrophage self-targeting, followed by phagocytosis independent of calreticulin Moreover, we identified spleen red pulp to be one specific tissue that provides stimuli constantly activating macrophage phagocytosis albeit lacking in Cd47(-/-) or Sirpα(-/-) mice., Competing Interests: The authors declare no conflict of interest.

Hepatic glucose production (HGP) normally begins just prior to birth. Prolonged fetal hypoglycemia, intrauterine growth restriction, and acute hypoxemia produce an early activation of fetal HGP. To test the hypothesis that prolonged hypoxemia increases factors which regulate HGP, studies were performed in fetuses that were bled to anemic conditions (anemic: n = 11) for 8.9 ± 0.4 days and compared with control fetuses (n = 7). Fetal arterial hematocrit and oxygen content were 32% and 50% lower, respectively, in anemic vs. controls (P < 0.005). Arterial plasma glucose was 15% higher in the anemic group (P < 0.05). Hepatic mRNA expression of phosphonenolpyruvate carboxykinase (PCK1) was twofold higher in the anemic group (P < 0.05). Arterial plasma glucagon concentrations were 70% higher in anemic fetuses compared with controls (P < 0.05), and they were positively associated with hepatic PCK1 mRNA expression (P < 0.05). Arterial plasma cortisol concentrations increased 90% in the anemic fetuses (P < 0.05), but fetal cortisol concentrations were not correlated with hepatic PCK1 mRNA expression. Hepatic glycogen content was 30% lower in anemic vs. control fetuses (P < 0.05) and was inversely correlated with fetal arterial plasma glucagon concentrations. In isolated primary fetal sheep hepatocytes, incubation in low oxygen (3%) increased PCK1 mRNA threefold compared with incubation in normal oxygen (21%). Together, these results demonstrate that glucagon and PCK1 may potentiate fetal HGP during chronic fetal anemic hypoxemia., (Copyright © 2016 the American Physiological Society.)

Background: For breast-conserving surgery, the method of margin assessment that most frequently achieves negative margins without increasing the volume of tissue excised is uncertain. We examined our institutional experience with three different margin assessment methods used by six experienced breast surgeons., Methods: Patients undergoing breast-conserving surgery for invasive carcinoma during July to December of a representative year during which each method was performed (perpendicular, 2003; tangential, 2004; cavity shave, 2011) were included. The effect of margin method on the positive margin rate at first excision and the total volume excised to achieve negative margins were evaluated by multivariable analysis, by surgeon, and by tumor size and presence of extensive intraductal component (EIC)., Results: A total of 555 patients were identified, as follows: perpendicular, 140; tangential, 124; and cavity shave, 291. The tangential method had a higher rate of positive margins at first excision than the perpendicular and cavity-shave methods (49, 15, 11 %, respectively; p < 0.0001). Median volumes to achieve negative margins were similar (55 ml perpendicular; 64 ml tangential; 62 ml cavity shave; p = 0.24). Four of six surgeons had the lowest rate of positive margins with the cavity-shave method, which was significant when compared to the tangential method (p < 0.0001) but not the perpendicular method (p = 0.37). The volume excised by the three methods varied by surgeon (p < 0.0001). The perpendicular method was optimal for T1 tumors without EIC; the cavity-shave method tended to be superior for T2-T3 tumors and/or EIC., Conclusions: Although the cavity-shave method may decrease the rates of positive margins, its effect on volume is variable among surgeons and may result in an increase in the total volume excised for some surgeons and for small tumors without EIC.

Objective: The objective of the study was to compare the effect of horizontal versus vertical closure of the vaginal cuff during vaginal hysterectomy on vaginal length., Study Design: Forty-three women were randomized to undergo horizontal (n = 23) or vertical (n = 20) vaginal cuff closure during vaginal hysterectomy at a community hospital. The primary outcome of vaginal length before and after surgery was compared by the Student t test and the paired t test., Results: Preoperatively mean vaginal lengths in the horizontal and vertical groups were statistically similar (7.76 +/- 1.23 cm versus 8.28 +/- 1.39 cm, respectively; P = .21). Postoperatively the groups statistically differed (6.63 +/- 1.02 cm versus 7.93 +/- 1.18 cm, P < .001). The mean change in vaginal length was -1.13 +/- 1.15 cm and -0.35 +/- 0.91 cm, respectively (P = .01). Within-group comparisons revealed a statistical difference between pre- versus postmean vaginal length in the horizontal group (7.76 +/- 1.23 cm versus 6.63 +/- 1.02 cm; P < .001) and no difference within the vertical group (8.28 +/- 1.39 cm versus 7.93 +/- 1.18 cm; P = .11)., Conclusion: Closing the vaginal cuff vertically is superior to horizontal closure for the purpose of preserving vaginal length.

We analyzed fatty acid make up of cells and organs from autoimmune and immunologically normal mice to determine whether intrinsic differences in composition might be associated with an inflammatory phenotype. Macrophages (MO) isolated from 4-6-week-old MRL lpr/lpr mice were cultured with phorbol ester (PMA), fibroblast growth factor-1 (FGF-1), fibroblast growth factor-2 (FGF-2) and medium control to determine whether these cell signals might induce membrane fatty acid changes. Individual phospholipid analysis showed 8.4- and 5.1-fold increases in phosphatidylcholine arachidonate (20:4) mole % over baseline values following culture with FGF-1 and FGF-2, respectively. Unfractionated analysis on kidney and liver extracts from 4-6 week MRL lpr/lpr, 16-20 week lpr and 12-20 week MRL +/-/+/- mice demonstrated no significant intrastrain fatty acid differences. Higher levels of 20:4 in 4-6 week lpr mice were noted compared to 16-20 week lpr or +/+ mice in kidney, and liver samples (P < 0.05). It is possible that membrane changes precipitated by microenvironmental cytokine concentrations may contribute to the expression of autoimmune disease in this model.

A room-temperature, pulsed, color-center laser using OH(-)-doped NaCl crystals is reported. Crystals were transversely pumped by a Q-switched Nd:YAG laser at 1.06microm and produced output energies of 8.6 mJ in 20-nsec pulses. The tuning range extended from 1.37 to 1.77 microm. During 40 h of operation (>10(6) pulses), a gradual power fading was observed. Laser action is tentatively ascribed to F(2)(+) centers.