Generation of mature dendritic cells from human blood. An improved method with special regard to clinical applicability

Two methods to generate human dendritic cells from hematopoietic precursor cells in peripheral blood have recently been published. One approach utilizes the rare CD34+ precursors and GM-CSF plus TNF-alpha. The other method makes use of the more abundant CD34- precursor population and GM-CSF plus IL-4. Here we report a method that is based on the latter approach. However, the GM-CSF and IL-4 treated cells are not stable mature dendritic cells, e.g., the characteristic morphology and nonadherence of dendritic cells is lost if the cytokines are removed. We describe the need for a monocyte-conditioned medium to generate fully mature and stable dendritic cells. This is achieved by adding a 3 day 'maturation culture' to the initial 6-7 day culture in the presence of GM-CSF and IL-4. Macrophage-conditioned medium contains the critical maturation factors. Mature dendritic cells are defined by their pronounced display of motile cytoplasmic processes ('veils'), their high capacity to induce proliferative responses in resting T cells, particularly in naive umbilical cord T cells, their down-regulated antigen processing ability, and their characteristic phenotype: expression of CD83, high levels of MHC molecules and CD86, lack of CD115 and perinuclear dot-like CD68 staining. These features are stable for at least 3 days upon withdrawal of cytokines and conditioned media. IL-4 can be replaced by IL-13. When CD34+ progenitors are depleted from blood, there is only a minor reduction in the yield of dendritic cells by this method. We have adapted the method to consider several variables that are pertinent to clinical use, including a change from fetal calf serum to human plasma and to media approved for clinical use like X-VIVO or AIM-V. 1% plasma and RPMI 1640 are currently optimal. Additional reagents used for cell culture (Ig. cytokines) and cell separation (immunomagnetic beads) are approved for or already used in clinical applications. For 40 ml blood, the yield is 0.8-3.3 x 10(6) mature dendritic cells as defined by the expression of the new dendritic cell-restricted marker CD83. CD83+ cells constitute between 30 and 80% of all cells recovered at the end of the culture period. Yields can be enhanced up to six-fold if the blood donors are pretreated with G-CSF. Stable, mature dendritic cells generated by this method should be a powerful tool for active immunotherapy.

Production of IL-12 by human monocyte-derived dendritic cells is optimal when the stimulus is given at the onset of maturation, and is further enhanced by IL-4

Dendritic cells produce IL-12 both in response to microbial stimuli and to T cells, and can thus skew T cell reactivity toward a Th1 pattern. We investigated the capacity of dendritic cells to elaborate IL-12 with special regard to their state of maturation, different maturation stimuli, and its regulation by Th1/Th2-influencing cytokines. Monocyte-derived dendritic cells were generated with GM-CSF and IL-4 for 7 days, followed by another 3 days +/- monocyte-conditioned media, yielding mature (CD83(+)/dendritic cell-lysosome-associated membrane glycoprotein(+)) and immature (CD83(-)/dendritic cell-lysosome-associated membrane glycoprotein(-)) dendritic cells. These dendritic cells were stimulated for another 48 h, and IL-12 p70 was measured by ELISA. We found the following: 1) Immature dendritic cells stimulated with CD154/CD40 ligand or bacteria (both of which concurrently also induced maturation) secreted always more IL-12 than already mature dendritic cells. Mature CD154-stimulated dendritic cells still made significant levels (up to 4 ng/ml). 2) Terminally mature skin-derived dendritic cells did not make any IL-12 in response to these stimuli. 3) Appropriate maturation stimuli are required for IL-12 production: CD40 ligation and bacteria are sufficient; monocyte-conditioned media are not. 4) Unexpectedly, IL-4 markedly increased the amount of IL-12 produced by both immature and mature dendritic cells, when present during stimulation. 5) IL-10 inhibited the production of IL-12. Our results, employing a cell culture system that is now being widely used in immunotherapy, extend prior data that IL-12 is produced most abundantly by dendritic cells that are beginning to respond to maturation stimuli. Surprisingly, IL-12 is only elicited by select maturation stimuli, but can be markedly enhanced by the addition of the Th2 cytokine, IL-4.

Nutrient-independent and nutrient-dependent factors stimulate protein synthesis in colostrum-fed newborn pigs

We hypothesized that nonnutrient components, including growth factors, present in colostrum contribute to the stimulation of protein synthesis in colostrum-fed neonatal pigs. We studied neonatal pigs fed mature milk, colostrum, or a formula containing a macronutrient composition comparable to that of colostrum for 24 h. We measured the circulating concentrations of insulin, insulin-like growth factor I, glucose, and amino acids at intervals throughout the 24-h period, after which we measured in vivo protein synthesis using a flooding dose of [3H]phenylalanine. The rates of protein synthesis in several tissues measured after 24 h of feeding were greater than those we reported previously after 6 h of feeding. The acute (within 6 h) stimulation of protein synthesis in visceral and skeletal muscle tissues of neonatal pigs fed milk, colostrum, or formula was primarily influenced by nutrient intake and associated with rapid secretion of insulin. Indirect evidence suggests that intestinal absorption of ingested colostral insulin was minimal. However, the sustained increase in tissue protein synthesis between 6 and 24 h coincided with an increase in circulating insulin-like growth factor I. We found a novel, specific stimulation of skeletal muscle and jejunal protein synthesis in colostrum-fed pigs that can be attributed to some nonnutrient component of colostrum.

Human renal-cell carcinoma tissue contains dendritic cells

Immune surveillance of cancer requires antigen-presenting cells which activate T cells specific for tumor-associated antigens. We show here that substantial numbers of dendritic cells, which are the most potent antigen-presenting cells, emigrate from renal-tumor explants in organ culture. Tumor-derived dendritic cells presented with all characteristics of mature dendritic cells. Dendritic cells could be identified by typical cytoplasmic projections (=veils). They expressed high levels of MHC products and of the co-stimulator CD86 (B7-2). Dendritic cells expressed the CD45RO isoform but not CD45RA. The most important point was that up to 9% of the emigrating leukocytes expressed the CD83 antigen, a specific marker for mature dendritic cells. CD83+ cells were approximately 40-fold enriched in the tumor tissue as compared to the peripheral blood. In contrast to cultured blood dendritic cells, tumor-emigrant dendritic cells had a reduced potential to capture soluble antigen, as shown by the exclusion of fluoresceinated Dextran molecules. Finally, in mixed leukocyte reactions, tumor-derived dendritic cells were able to stimulate naive T cells from cord blood, which is a unique feature of dendritic cells. This study demonstrates that genuine dendritic cells reside in or infiltrate renal-cell carcinoma tissue. The failure of patients with renal-cell carcinoma to mount an anti-tumor immune response despite the presence of professional antigen-presenting cells in the tumor tissue suggests that tumor-associated dendritic cells are suppressed in situ, in a similar way to that described for tumor-infiltrating lymphocytes.

Dendritic cells generated from blood precursors of chronic myelogenous leukemia patients carry the Philadelphia translocation and can induce a CML-specific primary cytotoxic T-cell response

Dendritic cells (DC) are professional antigen-presenting cells specialized in the initiation of primary immune responses. We were interested to know whether mature DC can be grown in vitro from peripheral blood mononuclear cells (PBMC) of patients with chronic myelogenous leukemia (CML), and whether they carry the Philadelphia (Ph) translocation. Using a method recently described, DC were generated from PBMC precursors of 12 patients with CML using GM-CSF, IL-4, and monocyte-conditioned medium. DC exhibited the typical morphology with thin cytoplasmatic processes and expressed high levels of MHC class II, CD86, and CD83 typical for mature DC. After sorting with the monoclonal antibody CD83, a cell population of more than 95% CD83 positive cells was obtained. The presence of the Ph translocation was analyzed in these cells, in PBMC, lymphoblastoid cell lines (LCL), and in phytohemagglutinin (PHA)-induced T blasts from the same patients by fluorescence in situ hybridization (FISH). In contrast to all other cells analyzed, the vast majority of DC (95.9 +/- 0.7%) displayed the Ph translocation, irrespective of disease stage or therapy. PBMC were predominantly positive for the Ph chromosome (67.6 +/- 7.3%), whereas only 11.4 +/- 1% of the B cells and 4.4 +/- 1.1% of the PHA blasts carried the Ph translocation. Using such leukemic DC as antigen-presenting cells, a primary CML-directed cytotoxic immune response in vitro was obtained, as shown by the specific recognition of Ph chromosome positive cells. We conclude that DC can be generated from blood progenitors of CML patients in vitro and exhibit, to a large extent, the Ph translocation. Such DC, which in a preliminary experiment have been able to induce a primary CML-directed cytotoxic immune response in vitro, might be ideal candidates for adoptive immunotherapy either by direct transfer of DC for in vivo generation of a T-cell response or by in vitro generation of CML-specific cytotoxic autologous or HLA-matched normal T-cell clones for use in vivo.

Distinct roles for PI3K in proliferation and survival of oligodendrocyte progenitor cells

Phosphoinositol 3-kinase (PI3K) is a downstream effector for multiple ligand-activated receptors and modulates cell responses through activation of its target protein kinase B (Akt). We examined the roles of PI3K-Akt signaling in a primary glial (oligodendrocyte) progenitor cell culture system that is ligand-dependent for cell proliferation, survival, and prevention of differentiation. We demonstrate that PI3K and Akt (Ser-473 phosphorylation) are activated in response to platelet-derived growth factor but not basic fibroblast growth factor-2 (FGF2) and that distinct forms of PI3K are activated in early progenitors and later-maturation pro-oligodendroblasts as identified by their sensitivity to wortmannin. By establishing conditions to examine effects on cell proliferation and survival independently, we demonstrate that PI3K is necessary for a full mitogenic response and that PI3K is also necessary for early progenitor survival. Our results therefore demonstrate that PI3K-Akt signaling independently regulates proliferation and survival, that the form of PI3K is distinct in early progenitors and pro-oligodendroblasts, and that FGF2 does not activate this pathway in either primary glial cell population.

Expression of maturation-/migration-related molecules on human dendritic cells from blood and skin

Progress in dendritic cell research has been overwhelming in the past few years. This was made possible by the recent development of simple methods to generate large numbers of dendritic cells. These methods use as starting populations for culture either CD34+ progenitor cells from cord blood or bone marrow, or monocytes from peripheral blood. The latter approach is critically dependent on the combination of GM-CSF and interleukin 4. Such "priming cultures" yield populations of immature dendritic cells (CD83-/CD86 +/- /CD115+/antigen uptake high/antigen processing high/T cell sensitization low). In order to generate mature dendritic cells a subsequent "differentiation culture" has to be added whereby monocyte-conditioned medium appears to be the optimal stimulus for maturation. This results in terminally mature dendritic cells (CD83+/CD86++/CD115-/antigen uptake low/antigen processing low/T cell sensitization high). We investigated the expression of some molecules involved in maturation and migration on human monocyte-derived dendritic cells from blood in comparison with dermal dendritic cells and epidermal Langerhans cells. We present a method to highly enrich epidermal Langerhans cells. Survival of purified Langerhans cells in culture is dependent on the presence of GM-CSF and TNF-alpha. During maturation a substantial part of the Langerhans cells loses expression of the cutaneous lymphocyte antigen (CLA); mature dendritic cells from the dermis are completely devoid of CLA. Similarly, CLA as well as CD15s (Sialyl Lewis x) and CD31 (PECAM-1) that can be readily detected on immature monocyte-derived dendritic cells are down-regulated upon maturation. CD68 expression is very low in cutaneous dendritic cells; in monocyte-derived dendritic cells this molecule is abundantly present. Subsets of monocyte-derived dendritic cells express E-cadherin; CD87 (urokinase plasminogen activator receptor) is weakly expressed on both immature and mature monocyte-derived dendritic cells. Taken together, these data suggest that the phenotype of monocyte-derived dendritic cells (E-cadherin low to negative, CD68++) is not indicative for a cutaneous destiny. Furthermore, the downregulation upon maturation of molecules involved in migration through vessel walls (CD31, CLA, CD15s) indicates that the entry of mature dendritic cells into lymphatic vessels may not be as rigidly regulated by adhesion molecules as the process of extravasation from blood vessels.

Colostrum enhances the nutritional stimulation of vital organ protein synthesis in neonatal pigs

Our objective was to determine the relative importance of the macronutrient components of colostrum in the stimulation of vital organ protein synthesis in neonatal pigs. We studied colostrum-deprived newborn pigs within 4-6 h after birth (unfed) and three groups fed for 24 h mature milk, colostrum, or a formula containing a macronutrient composition comparable to that of colostrum. We measured protein synthesis in vivo using a flooding dose of 3H-phenylalanine. The fractional rates of protein synthesis (Ks) in the brain, heart, lung, kidney and spleen were significantly higher in all fed groups than in the unfed newborns. Among the three fed groups, brain and heart protein synthesis rates were greater in colostrum-fed than in either milk- or formula-fed pigs. Kidney and spleen protein synthesis rates in colostrum- and formula-fed pigs were not significantly different, but both were higher than in milk-fed pigs. The stimulation of kidney protein synthesis in response to feeding was primarily a consequence of greater protein synthetic efficiency; however, protein synthetic capacity in the heart, lung and spleen was generally greater in colostrum- and formula-fed pigs than in unfed newborns. Our results suggest that the predominant stimulus for vital organ protein synthesis in colostrum-fed neonatal pigs is nutrient intake. However, there was a specific stimulation of both brain and heart protein synthesis in colostrum-fed pigs that cannot be attributed to macronutrients.

Proteomics reveals distinct mechanisms regulating the release of cytokines and alarmins during pyroptosis

A major pathway for proinflammatory protein release by macrophages is inflammasome-mediated pyroptotic cell death. As conventional secretion, unconventional secretion, and cell death are executed simultaneously, however, the cellular mechanisms regulating this complex paracrine program remain incompletely understood. Here, we devise a quantitative proteomics strategy to define the cellular exit route for each protein by pharmacological and genetic dissection of cellular checkpoints regulating protein release. We report the release of hundreds of proteins during pyroptosis, predominantly due to cell lysis. They comprise constitutively expressed and transcriptionally induced proteins derived from the cytoplasm and specific intracellular organelles. Many low-molecular-weight proteins including the cytokine interleukin-1β, alarmins, and lysosomal-cargo proteins exit cells in the absence of cell lysis. Cytokines and alarmins are released in an endoplasmic reticulum (ER)-Golgi-dependent manner as free proteins rather than by extracellular vesicles. Our work provides an experimental framework for the dissection of cellular exit pathways and a resource for pyroptotic protein release.

Generation of large numbers of human dendritic cells from whole blood passaged through leukocyte removal filters: an alternative to standard buffy coats

Many blood banks now use whole blood inline filtration to produce leukocyte-depleted blood products. As a result, a common source of large numbers of human dendritic cells (DC) for research purposes, namely standard buffy coats, has been lost. Therefore, we have adapted our conventional method for growing DC from CD14(+) precursors in order to make use of these filter units. A dextran solution containing human serum albumin was used to flush back the filters. After pelleting, mononuclear cells were obtained by standard density gradient centrifugation (Lymphoprep). To eliminate T cells, we used rosetting with sheep red blood cells. In addition to the classical PBMC, the cell population obtained after Lymphoprep centrifugation was found to contain high numbers of CD14(+) granulocytes which could be depleted by separation on an additional Percoll gradient. At this stage, FACS analysis revealed a cell population that resembled the CD14(+) monocyte-enriched population, obtained from traditional buffy coat preparations after Lymphoprep centrifugation and T cell elimination. Culture of the cells and the induction of maturation was identical to the previously described procedures, except that the culture time was reduced from 7 to 5 days and the maturation time from 3 to 2 days. Analyses of the major molecules indicative of DC maturation (CD83, CD86, CD208/DC-LAMP) and functional analyses of the T cell-stimulatory capacity of the DC population (using the MLR assay with normal peripheral T cells and naive T cells) revealed no major differences from buffy coat-derived DC preparations.

P38 kinases mediate NLRP1 inflammasome activation after ribotoxic stress response and virus infection

Inflammasomes integrate cytosolic evidence of infection or damage to mount inflammatory responses. The inflammasome sensor NLRP1 is expressed in human keratinocytes and coordinates inflammation in the skin. We found that diverse stress signals induce human NLRP1 inflammasome assembly by activating MAP kinase p38: While the ribotoxic stress response to UV and microbial molecules exclusively activates p38 through MAP3K ZAKα, infection with arthropod-borne alphaviruses, including Semliki Forest and Chikungunya virus, activates p38 through ZAKα and potentially other MAP3K. We demonstrate that p38 directly phosphorylates NLRP1 and that serine 107 in the linker region is critical for activation. NLRP1 phosphorylation is followed by ubiquitination of NLRP1PYD, N-terminal degradation of NLRP1, and nucleation of inflammasomes by NLRP1UPA-CARD. In contrast, activation of NLRP1 by nanobody-mediated ubiquitination, viral proteases, or inhibition of DPP9 was independent of p38 activity. Taken together, we define p38 activation as a unifying signaling hub that controls NLRP1 inflammasome activation by integrating a variety of cellular stress signals relevant to the skin.

Immune cell dynamics deconvoluted by single-cell RNA sequencing in normothermic machine perfusion of the liver

Normothermic machine perfusion (NMP) has emerged as an innovative organ preservation technique. Developing an understanding for the donor organ immune cell composition and its dynamic changes during NMP is essential. We aimed for a comprehensive characterization of immune cell (sub)populations, cell trafficking and cytokine release during liver NMP. Single-cell transcriptome profiling of human donor livers prior to, during NMP and after transplantation shows an abundance of CXC chemokine receptor 1⁺/2⁺ (CXCR1⁺/CXCR2⁺) neutrophils, which significantly decreased during NMP. This is paralleled by a large efflux of passenger leukocytes with neutrophil predominance in the perfusate. During NMP, neutrophils shift from a pro-inflammatory state towards an aged/chronically activated/exhausted phenotype, while anti-inflammatory/tolerogenic monocytes/macrophages are increased. We herein describe the dynamics of the immune cell repertoire, phenotypic immune cell shifts and a dominance of neutrophils during liver NMP, which potentially contribute to the inflammatory response. Our findings may serve as resource to initiate future immune-interventional studies.

Laparoscopic management of common bile duct stones

BACKGROUND

While laparoscopic cholecystectomy is widely accepted for therapy of cholecystolithiasis, controversy still exists concerning the management of common bile duct stones. Besides preoperative endoscopic papillotomy followed by laparoscopic cholecystectomy and open common bile duct surgery, management of common bile duct stones can be conducted by laparoscopy, if respective experience is available.

METHOD

During laparoscopic cholecystectomy a cholangiography via the cystic duct is routinely performed. If bile duct stones are detected they are retrieved via the cystic duct or via incision of the common bile duct by insertion of a Fogarty catheter or Dormia basket. Exclusion criteria against simultaneous laparoscopic management include suspicion of malignancy, severe pancreatitis, or cholangitis.

RESULTS

From November 1991 to March 2002, 200 patients primarily underwent laparoscopic therapy of bile duct stones. Retrieval was performed via cystic duct and common bile duct incision in 115 and 85 cases, respectively. Complete removal was achieved in 91%; complication rate and mortality was 7% and 0.5%, respectively. During the same period primary endoscopic papillotomy was necessary in 40 patients because of the above contraindications.

CONCLUSIONS

When correct indications and surgical expertise are observed, simultaneous laparoscopic management of common bile duct stones represents a safe and minimally invasive alternative to a two-procedure approach.

Influence of circadian clocks on adaptive immunity and vaccination responses

The adaptive immune response is under circadian control, yet, why adaptive immune reactions continue to exhibit circadian changes over long periods of time is unknown. Using a combination of experimental and mathematical modeling approaches, we show here that dendritic cells migrate from the skin to the draining lymph node in a time-of-day-dependent manner, which provides an enhanced likelihood for functional interactions with T cells. Rhythmic expression of TNF in the draining lymph node enhances BMAL1-controlled ICAM-1 expression in high endothelial venules, resulting in lymphocyte infiltration and lymph node expansion. Lymph node cellularity continues to be different for weeks after the initial time-of-day-dependent challenge, which governs the immune response to vaccinations directed against Hepatitis A virus as well as SARS-CoV-2. In this work, we present a mechanistic understanding of the time-of-day dependent development and maintenance of an adaptive immune response, providing a strategy for using time-of-day to optimize vaccination regimes.

Yoghurt and probiotic bacteria in dietary guidelines of the member states of the European Union

Beneficial microbes enter the food supply primarily through fermented foods (largely milks) and addition of probiotics. Fermented milks are a significant component of the diet of some geographical regions, including Europe. The fermentation process serves to preserve safety, nutritional quality and palatability of milk. In addition, the microbes associated with fermented milks and probiotics are associated with human health benefits. However, in the area of health claims only one claim for beneficial microbes has been approved in the European Union, that is for yoghurt to improve lactose tolerance. We searched for health messages that include probiotics or fermented milks in nutrition guidelines and recommendations in thirteen countries of the EU plus Switzerland. Such messages are allowed when they are made by non-commercial government bodies. Our analysis revealed that five EU member states have national nutrition guidelines or recommendations that include either probiotics or fermented milks with live bacteria. This supports that some EU member states recognise health benefits associated with consumption of live microbes, even if commercial marketing claims are not authorised. Harmonisation between recommendations and approved health-claims would benefit consumers and public health.

Dietary cholesterol supplementation improves growth and behavioral response of pigs selected for genetically high and low serum cholesterol

We hypothesized that, in pigs selected for low (L) or high (H) serum cholesterol for four generations, neonatal endogenous cholesterol synthesis would be sufficient to meet requirements for brain and body growth. In Experiment 1, eight 16-wk-old L pigs received a diet with or without 200 mg cholesterol/100 g diet for 35 d. Supplemented pigs grew approximately 25% faster and had a significantly greater concentration of free cholesterol in the cerebrum. In Experiment 2, 16 H and 16 L newborn pigs were fed a milk replacer with or without 200 mg cholesterol/100 g diet for 28 d. Pigs fed cholesterol had greater average daily gain (P < or = 0.09), significantly reduced liver 3-hydroxy-3-methylglutaryl-coenzyme A reductase activity, and significantly increased cerebral cholesterol content than pigs not fed cholesterol. One of three indices of exploratory behavior was significantly greater in the L pigs that received cholesterol compared with L pigs that did not receive cholesterol. These data suggest that these neonatal pigs are unable to produce sufficient cholesterol to meet requirements for normal growth and brain development and are dependent on dietary cholesterol in milk.

Effects of acute, submaximal exercise on skeletal muscle vitamin E

Vitamin E is the major lipid soluble anti-oxidant and may play an important protective role against free radicals produced during exercise. The purpose of this study was to determine the effect of a submaximal exercise bout on vitamin E levels in selected tissues. Five week- old lean, female Zucker rats were randomly divided into sedentary and run groups. At least 4 days following a maximal VO2 test, the run group (n = 7) ran on a treadmill at 70.3 +/- 1.5% VO2 max for 34-42 minutes. Duration was varied according to body weight to keep total work constant. Immediately post-exercise, animals were decapitated, exsanguinated and the quadriceps (red and white vastus lateralis), liver and heart quickly excised and stored under liquid nitrogen until analyzed. Lipids were extracted in heptane and alpha-tocopherol levels determined by reverse-phase HPLC with electrochemical detection. Quadriceps vitamin-E levels declined post-exercise p less than 0.01), and in the white quadriceps from 22 +/- 2 to 16 +/- 2 (p less than 0.05) nmol/g wet weight. No change in vitamin E content was noted for either heart (113 +/- 6 vs. 110 +/- 7, p less than 0.05) or liver (68 +/- 6 vs. 78 +/- 5, p greater than 0.05). It is concluded that a single bout of submaximal treadmill running can result in a significant depletion of vitamin E in skeletal muscle.

NCX1 represents an ionic Na+ sensing mechanism in macrophages

Inflammation and infection can trigger local tissue Na+ accumulation. This Na+-rich environment boosts proinflammatory activation of monocyte/macrophage-like cells (MΦs) and their antimicrobial activity. Enhanced Na+-driven MΦ function requires the osmoprotective transcription factor nuclear factor of activated T cells 5 (NFAT5), which augments nitric oxide (NO) production and contributes to increased autophagy. However, the mechanism of Na+ sensing in MΦs remained unclear. High extracellular Na+ levels (high salt [HS]) trigger a substantial Na+ influx and Ca2+ loss. Here, we show that the Na+/Ca2+ exchanger 1 (NCX1, also known as solute carrier family 8 member A1 [SLC8A1]) plays a critical role in HS-triggered Na+ influx, concomitant Ca2+ efflux, and subsequent augmented NFAT5 accumulation. Moreover, interfering with NCX1 activity impairs HS-boosted inflammatory signaling, infection-triggered autolysosome formation, and subsequent antibacterial activity. Taken together, this demonstrates that NCX1 is able to sense Na+ and is required for amplifying inflammatory and antimicrobial MΦ responses upon HS exposure. Manipulating NCX1 offers a new strategy to regulate MΦ function.

An inhibitor of cell proliferation associated with adhesion formation is suppressed by N,O-carboxymethyl chitosan

Surgical adhesions are a major cause of morbidity and mortality. The ideal barrier agent will both minimize adhesions and provide a milieu for the regeneration of the mesothelium lining of the abdominal and thoracic cavities. N,O-Carboxymethylchitosan (NOCC), a derivation of chitin that markedly reduces adhesions, may function to modulate intracellular signals such as growth factors and cytokines in the inflammatory exudate. Since transforming growth factor-beta is implicated in the fibrotic process, we investigated the possibility that NOCC's effects on adhesion formation reflects a modulation of TGF-beta activity. Using a biological assay for inhibition of cell proliferation to detect TGF-beta activity, we demonstrate that NOCC suppresses the levels of an inhibitor of cell proliferation released into serum and peritoneal exudates after cecal abrasion in the rat. However, this activity was distinct from known forms of TGF-beta as determined using both TGF-beta-neutralizing antisera and a TGF-beta-resistant cell proliferation assay. Thus at least one potential effect of NOCC involves a mechanism distinct from TGF-beta inhibition.

Exogenous insulin-like growth factor-I increases weight gain in intrauterine growth-retarded neonatal pigs

Many cases of intrauterine growth retardation (IUGR) are the result of placental insufficiency, suggesting that potential therapies should focus on the neonate rather than the pregnant female. We wished to determine whether IGF-I could be used therapeutically to stimulate normal rates of growth in these neonates. Eight sows received 2.3 kg/d of either a control (13% protein) or protein-restricted (0.5% protein) diet from d 63 of pregnancy to parturition. Litters were reduced to 6 pigs at 3 d of age, and IUGR neonates were fostered onto a control sow. Three pigs/ litter received an osmotic minipump containing either saline or recombinant human IGF-I, delivered at 4 microg/h from d 3 to d 10 of age. Tissue protein synthesis was measured in all pigs using a flooding dose of [3H]phenylalanine. At birth, both body weight (10%) and circulating IGF-I concentration (30%) were significantly lower in IUGR than in control newborns. The infusion of IGF-I to IUGR neonates significantly increased the circulating concentration of IGF-I, growth rate, and protein and fat accretion to control levels. The infusion of IGF-I did not alter concentrations of insulin, glucose, IGF-II, or the thyroid hormones. Our results suggest that IGF-I may be a potential therapy to restore normal growth in IUGR infants.

Effects of insulin and norepinephrine on glucose transport and metabolism in rat brown adipocytes. Potentiation by insulin of norepinephrine-induced glucose oxidation

Glucose is an important fuel for rat brown adipose tissue in vivo and its utilization is highly sensitive to insulin. In this study, the different glucose metabolic pathways and their regulation by insulin and norepinephrine were examined in isolated rat brown adipocytes, using [6-14C]glucose as a tracer. Glucose utilization was stimulated for insulin concentrations in the range of 40-1000 microU/ml. Furthermore, the addition of adenosine deaminase (200 mU/ml) or adenosine (10 microM) did not alter insulin sensitivity of glucose metabolism. The major effect of insulin (1 mU/ml) was a respective 7-fold and 5-fold stimulation of lipogenesis and lactate synthesis, whereas glucose oxidation remained very low. The 5-fold stimulation of total glucose metabolism by 1 mU/ml of insulin was accompanied by an 8-fold increase in glucose transport. In the presence of norepinephrine (8 microM), total glucose metabolism was increased 2-fold. This was linked to a 7-fold increase of glucose oxidation, whereas lipogenesis was greatly inhibited (by 72%). In addition, norepinephrine alone did not modify glucose transport. The addition of insulin to adipocytes incubated with norepinephrine, induced a potentiation of glucose oxidation, while lipogenesis remained very low. In conclusion, in the presence of insulin and norepinephrine glucose is a oxidative substrate for brown adipose tissue. However the quantitative importance of glucose as oxidative fuel remains to be determined.

Strain wave pathway to semiconductor-to-metal transition revealed by time-resolved X-ray powder diffraction

One of the main challenges in ultrafast material science is to trigger phase transitions with short pulses of light. Here we show how strain waves, launched by electronic and structural precursor phenomena, determine a coherent macroscopic transformation pathway for the semiconducting-to-metal transition in bistable Ti₃O₅ nanocrystals. Employing femtosecond powder X-ray diffraction, we measure the lattice deformation in the phase transition as a function of time. We monitor the early intra-cell distortion around the light absorbing metal dimer and the long range deformations governed by acoustic waves propagating from the laser-exposed Ti₃O₅ surface. We developed a simplified elastic model demonstrating that picosecond switching in nanocrystals happens concomitantly with the propagating acoustic wavefront, several decades faster than thermal processes governed by heat diffusion.

Female sex, young age, northern German residence, hypoglycemia and disabling diabetes complications are associated with depressed mood in the WHO-5 questionnaire - A multicenter DPV study among 17,563 adult patients with type 2 diabetes

BACKGROUND

Like other mental illnesses, depression is a culturally sensitive topic. Hence, findings cannot be transferred between countries. We investigated the frequency of depressed mood and its association with diabetes-related factors in a large type 2 diabetes (T2D) cohort from real-life care in Germany.

METHODS

17,563 adults (median [IQR]: 64.5[55.9-71.1] years) from the multicenter diabetes follow-up registry, DPV (diabetes prospective follow-up), were investigated. All had completed the WHO-5 questionnaire, a screening tool for depression. Logistic regression was applied to study the association of demographic and diabetes-related factors with depressed mood (SAS 9.4). P<0.05 was considered significant.

RESULTS

Using a WHO-5 cut-off of <13, 27.4% of patients were at risk for depressed mood. A clinical depression diagnosis was recognized in 8.4%. Female sex (OR: 1.5[95%-CI: 1.4-1.6]), young age (1.2[1.1-1.4]), longer diabetes duration (1.2[1.1-1.3]), and living in Northern Germany (1.3[1.2-1.4]) were each associated with increased odds for depressed mood. After adjusting for these confounders, worse glycemic control (1.4[1.3-1.5]), insulin use (1.3[1.2-1.4]), myocardial infarction (1.3[1.2-1.5]), stroke (1.8[1.5-2.0]), retinopathy (1.4[1.3-1.6]), renal failure (1.4[1.2-1.8]), diabetic foot syndrome (1.3[1.2-1.4]), severe hypoglycemia (1.5[1.2-1.9]), two or more inpatient admissions (2.1[1.8-2.4]), and longer duration of hospital stay (1-<14 days: 1.3[1.2-2.3]; >14 days: 2.1[1.9-2.3]) were related to depressed mood.

LIMITATION

Due to the cross-sectional design, no causality can be drawn.

CONCLUSIONS

In T2D, depressed mood is not uncommon. However, in routine care a clinical depression might be missed and regular screening is advisable. Besides the well-known associations with depressed mood, northern German residence and mainly life-compromising diabetes comorbidities were identified as related factors.

Psoriasis and Diabetes: A Multicenter Study in 222078 Type 2 Diabetes Patients Reveals High Levels of Depression

OBJECTIVE

This study aimed to investigate the association between psoriasis and disease outcome in type 2 diabetes (T2D).

METHODS

222078 T2D patients (≥10 years old) from the prospective, multicenter diabetes patient registry were analyzed. Specific search items were used to identify psoriasis patients. Multiple regression models were fitted and adjusted for demographic confounder.

RESULTS

232 T2D patients had comorbid psoriasis. After adjusting psoriasis patients revealed a higher BMI (31.8 [31.0; 32.6] versus 30.6 [30.5; 30.6] kg/m2, p = 0.004) and HbA1c (64.8 [62.1; 67.6] versus 59.0 [58.9; 59.1] mmol/mol, p < 0.0001). Insulin was used more frequently (62.3 [55.7; 68.5] versus 50.9 [50.7; 51.1] %, p = 0.001), only OAD/GLP-1 was similar, and nonpharmacological treatment was less common (13.3 [9.5; 18.3] versus 21.9 [21.7; 22.1] %, p = 0.002). Severe hypoglycemia (0.31 [0.238; 0.399] versus 0.06 [0.057; 0.060] events per patient-year, p < 0.0001), hypertension (86.1 [81.1; 90.0] versus 68.0 [67.8; 68.2] %, p < 0.0001), and thyroid disease (14.0 [10.1; 19.2] versus 4.6 [4.5; 4.7] %, p < 0.0001) were more prevalent. Depression occurred more often (10.5 [7.1; 15.2] versus 2.8 [2.7; 2.8] %, p < 0.0001).

CONCLUSIONS

Clinical diabetes characteristics in psoriasis T2D patients were clearly worse compared to patients without psoriasis. Comorbid conditions and depression were more prevalent, and more intensive diabetes therapy was required.

Increased levels of surgical adhesions in TGFbeta1 heterozygous mice

Adhesion formation and fibrosis represent a major complication of surgical intervention. Reducing the morbidity associated with adhesions requires an understanding of the mechanisms underlying their formation. Since increased levels of transforming growth factor-beta1 (TGFbeta1) have been associated with inflammation and adhesion production, we investigated the requirement of TGFbeta1 in peritoneal adhesion formation utilizing mice carrying a targeted disruption of the TGFbeta1 allele. Mice that were either wild-type (+/+), containing two normal alleles of TGFbeta1, or heterozygous (+/-) for the TGFbeta1 null allele received injections of magnesium silicate (talc), and the extent of abdominal adhesions was determined utilizing a standard grading score. Wild-type (+/+) animals had at least twofold more TGFbeta1 protein in peritoneal fluids at 2 h posttrauma compared to heterozygous (+/-) mice (727 vs. 243 pg TGFbeta1/mg protein by enzyme-linked immunosorbent assay (ELISA) in +/+ and +/- mice, respectively), and had significantly less scar and adhesion formation (p < .05) at 7 days posttrauma (1.8 +/- 0.8 vs. 3.4 +/- 1.4, graded from 0 to 5, in +/+ and +/- mice, respectively). These results demonstrate that haploid insufficiency in TGFbeta1 levels can lead to inappropriate matrix and adhesion production during inflammation, and together with previous studies suggest that any perturbation of normal TGFbeta1 levels can modulate the injury response that regulates the extent of adhesion formation.