Brucella invasion of human intestinal epithelial cells elicits a weak proinflammatory response but a significant CCL20 secretion

In spite of the frequent acquisition of Brucella infection by the oral route in humans, the interaction of the bacterium with cells of the intestinal mucosa has been poorly studied. Here, we show that different Brucella species can invade human colonic epithelial cell lines (Caco-2 and HT-29), in which only smooth species can replicate efficiently. Infection with smooth strains did not produce a significant cytotoxicity, while the rough strain RB51 was more cytotoxic. Infection of Caco-2 cells or HT-29 cells with either smooth or rough strains of Brucella did not result in an increased secretion of TNF-α, IL-1β, MCP-1, IL-10 or TGF-β as compared with uninfected controls, whereas all the infections induced the secretion of IL-8 and CCL20 by both cell types. The MCP-1 response to flagellin from Salmonella typhimurium was similar in Brucella-infected or uninfected cells, ruling out a bacterial inhibitory mechanism as a reason for the weak proinflammatory response. Infection did not modify ICAM-1 expression levels in Caco-2 cells, but increased them in HT-29 cells. These results suggest that Brucella induces only a weak proinflammatory response in gut epithelial cells, but produces a significant CCL20 secretion. The latter may be important for bacterial dissemination given the known ability of Brucella to survive in dendritic cells.Facultad de Ciencias Exacta

Prevenci?n y tratamiento de las lesiones asociadas a la humedad (LESCAH)

El t?rmino lesi?n cut?nea asociada a la humedad (LESCAH) es un concepto general que incluye en su definici?n de lesi?n el efecto de la humedad con otros agentes agresores y un efecto de la misma sobre la piel. Hasta hace algunos a?os, solo se relacionaban las LESCAH con las dermatitis asociadas a incontinencia urinaria y/o fecal (DAI), obvi?ndose otras lesiones por humedad producidas por la presencia de exudados, productos l?quidos irritantes, sudor, salivaci?n excesiva, moco, etc.O termo lesi?n cut?nea asociada ? humidade (LESCAH) ? un concepto xeral que incl?e na s?a definici?n de lesi?n o efecto da humidade con outros axentes agresores e un efecto da mesma sobre a pel. Ata hai alg?ns anos, s? relacion?banse as LESCAH coas dermatites asociadas a incontinencia urinaria e/o fecal (DAI), obvi?ndose outras lesi?ns por humidade producidas pola presenza de exudados, produtos l?quidos irritantes, suor, salivaci?n excesiva, moco etc

Successful pregnancy in a patient with short bowel syndrome after surgical rehabilitation and sGLP-2 treatment: novel report on endogenous GLP-2 levels at delivery and during breastfeeding

Pregnant patients with short bowel syndrome (SBS) and chronic intestinal failure (CIF) can successfully reach to term their pregnancies while on parenteral nutrition (PN) but with high rates of complications. The combination of rehabilitation surgery, combined with the use of novel treatment with enterohormones, especially semisynthetic glucagon-like peptide 2 (sGLP-2), has increased the chances to achieve intestinal sufficiency. Here, we report the case of a 33-year-old female with SBS/CIF (anatomy type 2), weaned off PN using sGLP-2 for 3.7 years, discontinued when she became pregnant. She was able to carry the pregnancy to term without any additional PN support. Considering that, we queried if the endogenous GLP-2 (eGLP-2) levels in this SBS patient, during the pregnancy and breastfeeding period, could be like those presented in healthy pregnant women and in non-pregnant SBS patients. Also, we inquired if there was any passage or increase in the plasmatic eGLP-2 from the fetus to the mother. Thus, we determined eGLP-2 levels in paired neonatal (cord blood) and maternal plasma samples from the SBS pregnant patient (n = 1), healthy pregnant women (controls, n = 2), and non-pregnant SBS patients (n = 12). The results indicated that the SBS pregnant patient showed higher eGLP-2 levels than non-SBS pregnant patients and healthy pregnant women along all the period studied. Furthermore, we found that the maternal sample had higher eGLP-2 levels than the neonatal sample, suggesting that fetal contribution to maternal eGLP2 levels would be minor. In conclusion, this study not only reports for the first time a case of a patient with SBS that was able to achieve intestinal adaptation after combining the use of autologous reconstructive surgery and sGLP-2, but also enlightens the possibility of carrying out an uneventful pregnancy and lactation without any nutritional support and remaining independent of sGLP-2.Fil: Gentilini, Maria Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Medicina Traslacional, Trasplante y Bioingeniería. Fundación Favaloro. Instituto de Medicina Traslacional, Trasplante y Bioingeniería; ArgentinaFil: Doeyo, M.. Fundación Favaloro; ArgentinaFil: Ortega, M.. Fundación Favaloro; ArgentinaFil: Illidge Perez, L.. Fundación Favaloro; ArgentinaFil: Rumbo, C.. Fundación Favaloro; ArgentinaFil: Arriola Benitez, Paula Constanza. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Medicina Traslacional, Trasplante y Bioingeniería. Fundación Favaloro. Instituto de Medicina Traslacional, Trasplante y Bioingeniería; ArgentinaFil: Crivelli, A.. Fundación Favaloro; ArgentinaFil: Rumbo, Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Estudios Inmunológicos y Fisiopatológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Estudios Inmunológicos y Fisiopatológicos; ArgentinaFil: Solar, H.. Fundación Favaloro; ArgentinaFil: Gondolesi, Gabriel Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Medicina Traslacional, Trasplante y Bioingeniería. Fundación Favaloro. Instituto de Medicina Traslacional, Trasplante y Bioingeniería; Argentin

Ring Closing Alkyne Metathesis. Comparative Investigation of Two Different Catalyst Systems and Application to the Stereoselective Synthesis of Olfactory Lactones, Azamacrolides, and the Macrocyclic Perimeter of the Marine Alkaloid Nakadomarin A

Previously unknown ring closing metathesis reactions of diynes are described which open an efficient and stereoselective entry into macrocyclic (Z)-alkenes if the resulting cycloalkyne products are subjected to Lindlar reduction. This new two-step strategy offers significant advantages in stereochemical terms over conventional RCM of dienes which usually leads to (E,Z)-mixtures when applied to the formation of large rings. The tungsten alkylidyne complex (tBuO)3W⋮CCMe3(1a) and analogues thereof as well as a structurally unknown species formed in situ from Mo(CO)6 and p-chlorophenol effect the crucial alkyne metathesis reactions in a highly efficient manner, with the former catalyst being more tolerant toward structural variations of the substrates and polar functional groups. Applications to the stereoselective synthesis of the olfactory compounds ambrettolide 23 and yuzu lactone 24, the insect repellent azamacrolides epilachnene 31 and homoepilachnene 33, as well as to the fully functional building block 64 required for a total synthesis of the cytotoxic alkaloid nakadomarin A 51 highlight the relevance of this new concept for natural product chemistry. In the latter case, the diyne substrate 62 necessary for ring closing alkyne metathesis was obtained via a novel furan synthesis relying on a palladium-catalyzed opening of a vinyl epoxide followed by an oxidative cyclization of the heterocyclic ring

Transgenic mouse model harboring the transcriptional fusion Ccl20-luciferase as a novel reporter of pro-inflammatory response

The chemokine CCL20, the unique ligand of CCR6 functions as an attractant of immune cells. Expression of CCL20 is induced by Toll-like Receptor (TLR) signaling or proinflammatory cytokine stimulation. However CCL20 is also constitutively produced at specific epithelial sites of mucosa. This expression profile is achieved by transcriptional regulation. In the present work we characterized regulatory features of mouse Ccl20 gene. Transcriptional fusions between the mouse Ccl20 promoter and the firefly luciferase (luc) encoding gene were constructed and assessed in in vitro and in vivo assays. We found that liver CCL20 expression and luciferase activity were upregulated by systemic administration of the TLR5 agonist flagellin. Using shRNA and dominant negative form specific for mouse TLR5, we showed that this expression was controlled by TLR5. To address in situ the regulation of gene activity, a transgenic mouse line harboring a functional Ccl20-luc fusion was generated. The luciferase expression was highly concordant with Ccl20 expression in different tissues. Our data indicate that the transgenic mouse model can be used to monitor activation of innate response in vivo.Laboratorio de Investigaciones del Sistema InmuneFacultad de Ciencias Exacta

Neutrophil extracellular traps stimulate proinflammatory responses in human airway epithelial cells

Tissue injury leads to the release of uric acid (UA). At high local concentrations, UA can form monosodium urate crystals (MSU). MSU and UA stimulate neutrophils to release extracellular traps (NET). Here, we investigated whether these NET could be involved in the development of inflammation by stimulating cytokine release by airway epithelial cells. We found that NET significantly increased the secretion of CXCL8/IL-8 and IL-6 by alveolar and bronchial epithelial cells. These effects were not observed when NETosis was inhibited by Diphenyleneiodonium, elastase inhibitor, or Cl-amidine. Similar findings were made with NET induced by cigarette smoke extract, suggesting that NET proinflammatory capacity is independent of the inducing stimulus. Furthermore, NET affected neither the viability and morphology of epithelial cells nor the barrier integrity of polarized cells. The epithelial stimulatory capacity of NET was not affected by degradation of DNA with micrococcal nuclease, treatment with heparin, or inhibition of the elastase immobilized to DNA, but it was significantly reduced by pretreatment with an anti-HMGB-1 blocking antibody. Altogether, our findings indicate that NET exert direct proinflammatory effects on airway epithelial cells that might contribute in vivo to the further recruitment of neutrophils and the perpetuation of inflammation upon lung tissue damage.Instituto de Estudios Inmunológicos y Fisiopatológico

Brucella invasion of human intestinal epithelial cells elicits a weak proinflammatory response but a significant CCL20 secretion

In spite of the frequent acquisition of Brucella infection by the oral route in humans, the interaction of the bacterium with cells of the intestinal mucosa has been poorly studied. Here, we show that different Brucella species can invade human colonic epithelial cell lines (Caco-2 and HT-29), in which only smooth species can replicate efficiently. Infection with smooth strains did not produce a significant cytotoxicity, while the rough strain RB51 was more cytotoxic. Infection of Caco-2 cells or HT-29 cells with either smooth or rough strains of Brucella did not result in an increased secretion of TNF-α, IL-1β, MCP-1, IL-10 or TGF-β as compared with uninfected controls, whereas all the infections induced the secretion of IL-8 and CCL20 by both cell types. The MCP-1 response to flagellin from Salmonella typhimurium was similar in Brucella-infected or uninfected cells, ruling out a bacterial inhibitory mechanism as a reason for the weak proinflammatory response. Infection did not modify ICAM-1 expression levels in Caco-2 cells, but increased them in HT-29 cells. These results suggest that Brucella induces only a weak proinflammatory response in gut epithelial cells, but produces a significant CCL20 secretion. The latter may be important for bacterial dissemination given the known ability of Brucella to survive in dendritic cells.Facultad de Ciencias Exacta

The effect of the COVID-19 pandemic in intestinal rehabilitation and transplant patients, initial results of an international survey

Introduction: On January 30, 2020 the World Health Organization (WHO) declared the 2019-CoV outbreak in China as a global public health emergency and subsequently, a pandemic on March 11th. It was considered that intestinal failure and intestinal transplant patients might have a higher risk of severe complications from the COVID-19 disease, multidisciplinary intestinal failure teams had to adapt their clinical approaches in order to keep this vulnerable group of patients as safe as possible during the pandemic; but data was lacking. Therefore, in order to improve our knowledge, we designed a voluntary, international survey aiming to address the impact of the COVID-19 disease in intestinal failure and transplant patients worldwide. Patient and Methods: A retrospective, observational, multicenter survey was sent to all centers registered at the Intestinal Rehabilitation and Transplant Association (IRTA). The survey contained three modules: the 1st one consisted of 14 questions about the hospital\u27s activity during the COVID-19 pandemic. The 2nd one, contained 43 questions, was about intestinal failure patient management and outcome and the 3rd one (52 questions) focused on intestinal transplant patients. We used the Google Form platform. We aim to present the preliminary results of the first module. Statistical analysis was performed with the IBM SPSS Statistic version 25.0® program. Results: 13/42 (41%) centers responded; including centers from France, Netherlands, Italy, United States, UK, Sweden, Germany and Argentina. Only 2 centers reported moratorium on intestinal (IT) or multivisceral transplant (MVT), with a mean of 3 months (±4) [Table 1]. Since the pandemic started, 2 institutions reported 4 patients with intestinal rehabilitation or on TPN diagnosed with COVID-19 while 7 centers hospitals claimed to have had 9 patients post-IT/MTV affected by the disease. While 7 centers had their routine follow up and \u27protocol biopsies\u27 in the post-IT/MTV affected, none reported higher rates of rejection or complications. At the same time, 8 centers (77%) were affected by a mean of 15% decrease in referrals for new evaluations of intestinal failure or transplantation (compared to 2019) [Figure 1]. All centers adapted to utilizing telemedicine to follow up on IT/MVT patients. Conclusions: Many aspects of healthcare have been impacted by the COVID-19 pandemic. The survey showed that the number of affected patients has been lower than expected, the reduced number of centers required transient moratorium of their activity, but a secondary observation was that despite the availability of telemedicine, and probably related to the lockdown, there has been a significant reduction in the referrals for evaluation of intestinal failure and transplant patients, that may have the deleterious effect of the delay of treatment in health care system

Galactomannan as a potential modulator of intestinal ischemia–reperfusion injury

Background: Galactomannan (GAL), a polysaccharide present on the cell wall of several fungi, has shown an ability to modulate inflammatory responses through the dectin-1 receptor in human macrophages. However, studies evaluating the modulatory properties of this polysaccharide in in vivo inflammatory scenarios are scarce. We hypothesized that GAL pretreatment would modulate local and remote damage related to intestinal reperfusion after an ischemic insult. Materials and methods: Adult male Balb/c mice were subjected to intestinal ischemia–reperfusion injury by reversible occlusion of the superior mesenteric artery, consisting of 45 min of ischemia followed by 3 or 24 h of reperfusion. Intragastric GAL (70 mg/kg) was administered 12 h before ischemia, and saline solution was used in the control animals. Jejunum, lung, and blood samples were taken for the analysis of histology, gene expression, plasma cytokine levels, and nitrosative stress. Results: Intestinal and lung histologic alterations were attenuated by GAL pretreatment, showing significant differences compared with nontreated animals. Interleukin 1β, monocyte chemoattractant protein 1, and IL-6 messenger RNA expression were considerably downregulated in the small intestine of the GAL group. In addition, GAL treatment significantly prevented plasma interleukin 6 and monocyte chemoattractant protein 1 upregulation and diminished nitrate and nitrite levels after 3 h of intestinal reperfusion. Conclusions: GAL pretreatment constitutes a novel and promising therapy to reduce local and remote damage triggered by intestinal ischemia–reperfusion injury. Further in vivo and in vitro studies to understand GAL's modulatory effects are warranted.Fil: Stringa, Pablo. Hospital Universitario la Paz; EspañaFil: Toledano, Victor. Hospital Universitario la Paz; EspañaFil: Papa Gobbi, Rodrigo. Hospital Universitario la Paz; EspañaFil: Arreola, Miguel. Hospital Universitario la Paz; EspañaFil: Largo, Carlota. Hospital Universitario la Paz; EspañaFil: Machuca, Mariana. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Aguirre, Luis A.. Hospital Universitario la Paz; EspañaFil: Rumbo, Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Estudios Inmunológicos y Fisiopatológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Estudios Inmunológicos y Fisiopatológicos; ArgentinaFil: López Collazo, Eduardo. Hospital Universitario la Paz; EspañaFil: Hernández Oliveros, Francisco. Hospital Universitario la Paz; Españ

Modelo experimental murino de isquemia-reperfusión intestinal y su impacto en órganos remotos

La falla multiorgánica es una de las causas de morbi-mortalidad en pacientes con trasplante intestinal. La lesión por isquemia-reperfusión intestinal (IRI) provoca ruptura de la barrera del intestino con impacto en órganos distantes, ya sea por sepsis, traslocación bacteriana o por activar una respuesta inflamatoria sistémica Objetivos: evaluar la respuesta histológica del tejido intestinal, pulmonar y hepático luego de un período de 35 minutos de isquemia intestinal por clampeo de la arteria mesentérica superior (AMS) seguidos de 60 minutos de reperfusión.Facultad de Ciencias Médica