Ramses Wassef
Université de Montréal
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Featured researches published by Ramses Wassef.
Blood | 2012
Keiko Wakahara; Nobuyasu Baba; Vu Quang Van; Philippe Bégin; Manuel Rubio; Pasquale Ferraro; Benoît Panzini; Ramses Wassef; Raymond Lahaie; Yves Caussignac; Raja Tamaz; Geneviève Soucy; Guy Delespesse; Marika Sarfati
Basophils are a rare population of granulocytes that have long been associated with IgE-mediated and Th2-associated allergic diseases. However, the role of basophils in Th17 and/or Th1 diseases has not been reported. In the present study, we report that basophils can be detected in the mucosa of Th17-associated lung and inflammatory bowel disease and accumulate in inflamed colons containing large quantities of IL-33. We also demonstrate that circulating basophils increased memory Th17 responses. Accordingly, IL-3- or IL-33-activated basophils amplified IL-17 release in effector memory T cells (T(EM)), central memory T cells (T(CM)), and CCR6(+) CD4 T cells. More specifically, basophils promoted the emergence of IL-17(+)IFN-γ(-) and IL-17(+)IFN-γ(+), but not IL-17(-)IFN-γ(+) CD4 T cells in T(EM) and T(CM). Mechanistic analysis revealed that the enhancing effect of IL-17 production by basophils in T(EM) involved the ERK1/2 signaling pathway, occurred in a contact-independent manner, and was partially mediated by histamine via H(2) and H(4) histamine receptors. The results of the present study reveal a previously unknown function for basophils in augmenting Th17 and Th17/Th1 cytokine expression in memory CD4 T cells. Because basophils accumulated in inflamed inflammatory bowel disease tissues, we propose that these cells are key players in chronic inflammatory disorders beyond Th2.
Canadian Journal of Gastroenterology & Hepatology | 2006
Evelyne Vinet; Pierre Perreault; Louis Bouchard; Denis Bernard; Ramses Wassef; Richard Letourneau; Gilles Pomier-Layrargues
Surgery in cirrhotic patients is associated with high morbidity and mortality related to portal hypertension and liver insufficiency. Therefore, preoperative portal decompression is a logical approach to facilitate abdominal surgery and hopefully to improve postoperative survival. The present study evaluated the clinical outcomes of 18 patients (mean age 58 years) with cirrhosis (seven alcoholics and 11 nonalcoholics) who underwent transjugular intrahepatic portosystemic shunt (TIPS) placement before antrectomy (n=5), colectomy (n=10), small-bowel resection (n=1), pancreatectomy (n=1) and nephrectomy (n=1). TIPS was performed a mean (+/-SD) of 72+/-21 days before surgery and induced a marked mean decrease in portohepatic gradient from 21.4+/-3.9 mmHg to 8.4+/-3.4 mmHg. Cirrhotic patients (n=17) who underwent elective abdominal surgery without preoperative TIPS placement were used as the control group. Both groups were matched for age, etiology of cirrhosis, indications for surgery, type of surgery and coagulation parameters. The mean Pugh score was significantly higher in the TIPS group (7.7 versus 6.2). No significant differences were observed for operative blood loss, postoperative complications, duration of hospitalization and one-month (83% versus 88%) or one-year (54% versus 63%) cumulative survival rate. Analysis using the Cox proportional hazards model showed that neither TIPS placement nor preoperative Pugh score were independent predictors for survival. The present study suggests that preoperative TIPS placement does not improve postoperative evolution after abdominal surgery in cirrhotic patients with good or moderately impaired liver function.
Journal of Experimental Medicine | 2013
Nobuyasu Baba; Vu Quang Van; Keiko Wakahara; Manuel Rubio; Geneviève Fortin; Benoît Panzini; Geneviève Soucy; Ramses Wassef; Raja Tamaz; Raymond Lahaie; Edmond-Jean Bernard; Yves Caussignac; Raymond Leduc; Rasmy Lougnarath; Carole Bergeron; Marc-André Racicot; Fanny Bergeron; Marie-Andrée Panzini; Pieter Demetter; Denis Franchimont; Knut Schäkel; Gisbert Weckbecker; Frank Kolbinger; Christoph Heusser; Thomas Huber; Karl Welzenbach; Marika Sarfati
CD172a+ cells producing IL-1β and TNF are increased in inflamed tissues in Crohn’s disease and can be targeted by CD47 fusion protein.
Journal of Leukocyte Biology | 2015
Marwa Bsat; Laurence Chapuy; Nobuyasu Baba; Manuel Rubio; Benoît Panzini; Ramses Wassef; Geneviève Soucy; Heena Mehta; Marika Sarfati
Human Slan DCs have been studied in patients with psoriasis, rheumatoid arthritis, cancer, and autoimmune diseases. In this study, we investigated the frequency, phenotype, and function of Slan DCs in blood, colon, as well as mLNs of patients with IBD. We first show that the frequency of circulating CD14dullSlan DCs was reduced in CD patients refractory to immunosuppressive drugs or TNF‐α blockers relative to untreated CD, UC, and healthy subjects. In blood of CD patients, Slan DCs expressed CD172a, as detected by CD47 fusion protein binding, when compared with its lack of expression in control subjects. Next, we demonstrate that CD172a+Slan DCs that produced IL‐1β and TNF‐α accumulated in mLNs and colons of CD patients. The CD172a+Slan DCs up‐regulated their expression of CD14 in CD tissues and the proinflammatory cytokines were produced in CD14brightCD172a+Slan DCs. By contrast, no difference was noted in the frequency of Slan DCs between inflamed, noninflamed colonic mucosa of UC patients and control, non‐IBD donors. Finally, the percentage of cytokine‐producing Slan DCs also augmented in response to TLR2 and NOD2 in in vitro stimulation in PBMCs of CD, but not UC, patients. In conclusion, we propose that proinflammatory CD14brightCD172a+Slan DCs are a distinguishing feature between CD and UC, as these cells accumulate uniquely in mLNs and colonic mucosa of CD patients. Thus, Slan DCs may contribute to CD immunopathogenesis.
Diseases of The Colon & Rectum | 1989
Denis Bernard; Stephen Morgan; Daniel Tassé; Ramses Wassef
World Journal of Surgery | 1991
Michel H. Dagenais; Denis Bernard; Denis Marleau; Stephen Morgan; Daniel Tassé; Ramses Wassef; Jean-Pierre Villeneuve; Gilles Pomier-Layrargues; Bernard Willems; Pierre Lavoie
The Journal of Allergy and Clinical Immunology | 2014
Laurence Chapuy; Marwa Bsat; Heena Mehta; Manuel Rubio; Keiko Wakahara; Vu Quang Van; Nobuyasu Baba; Cheolho Cheong; Tae Jin Yun; Benoît Panzini; Ramses Wassef; Raja Tamaz; Geneviève Soucy; Guy Delespesse; Marika Sarfati
Gastroenterology | 2003
Evelyne Vinet; Pierre Perreault; Louis Bouchard; Denis Bernard; Ramses Wassef; Gilles Pomier-Layrargues
Journal of the Canadian Association of Gastroenterology | 2018
J Hercun; Ramses Wassef; Raymond Lahaie; Pierre Poitras
Journal of Clinical Oncology | 2018
Mohammed A. Al-Harthi; Olivier Charette; Éric Debroux; Francois Dagbert; Richard Ratelle; Ramses Wassef; Rasmy Loungnarath