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Nadine Cerf-Bensussan

Publications and source records attributed to Nadine Cerf-Bensussan.

At least 19 recordsLinked to original sources
PubMed2006

Oral proteases: a new approach to managing coeliac disease.

A life-long but constraining gluten-free diet is the only treatment currently available for coeliac disease. The human gastrointestinal tract does not possess the enzymatic equipment to efficiently cleave the gluten-derived proline-rich peptides driving the abnormal immune intestinal response in patients with coeliac disease. Oral therapy by exogenous prolylendopeptidases able to digest ingested gluten was therefore propounded as an alternative treatment to the diet. The feasibility of this approach is discussed by reviewing recent data on the intestinal transport of gliadin peptides, properties of available enzymes and preliminary clinical assays. Development of new enzymes or enzymatic cocktails offers potentially more potent therapeutic tools that, however, need meticulous evaluation based on clinical, biological and histological criteria.

Administration, Oral↗
PubMed2006

Anti-LFA-1 antibody postpones T-cell receptor triggering while preserving generation of regulatory T cells in T-cell receptor anti-HY transgenic mice.

BACKGROUND: Anti-LFA-1 (CD11a) antibody increases allograft survival and/or induces tolerance in murine models, but its mechanisms of action remain to be elucidated. METHODS: Rag-2-/- H-2b recipient mice, bearing a transgenic T-cell receptor specific for the male antigen HY presented by MHC class II molecule, were transplanted with a C57BL/6 (H-2b) male heart with or without administration of anti-LFA-1 antibody from days -1 to 9. RESULTS: Treatment prevented the transient episode of acute graft rejection observed in nontreated mice and maintained a naive phenotype and proliferative characteristics comparable to that of naive transgenic lymphocytes on day 7 during treatment, with decreased IFN-gamma mRNA and increased IL-4 mRNA. On day 14, phenotype and proliferative response of lymphocytes in treated mice was comparable to those of untreated animals. Furthermore, treatment did not interfere with the generation of CD4+Vbeta6+CD25+ (Foxp3) cells that were observed in long-term nontreated tolerant mice. CONCLUSIONS: This in vivo model demonstrates that anti-LFA-1 treatment induced a transient blockade of antigen recognition, which inhibited and postponed induction of signal 1 via the TCR and decreased the intensity of the Th1 response. Importantly, LFA-1 blockade did not disturb spontaneous generation of regulatory mechanism. This treatment would be compatible in clinical settings with other therapeutics inducing regulatory mechanisms.

Animals↗
PubMed2006

Adulthood-onset celiac disease is associated with intercellular adhesion molecule-1 (ICAM-1) gene polymorphism.

Celiac disease (CD) is a multifactorial T-cell-mediated autoimmune disease characterized by gluten-triggered villous atrophy and malabsorption. Although human leukocyte antigen (HLA) class II genes are strong susceptibility factors, non-HLA genes likely contribute to most of CD predisposition. The intercellular adhesion molecule-1 (ICAM-1) gene is a good candidate for CD predisposition because its encoded protein acts as an adhesion and costimulatory receptor. Two single-base polymorphisms (G/A in exon 4 encoding G241R, and A/G in exon 6 encoding K469E) were analyzed in 180 French Caucasian CD case patients (110 patients diagnosed before the age of 15 and 70 patients after the age of 18), and 212 French Caucasian healthy controls. The R241 allele frequency was increased in CD case patients compared with controls (14.2% vs. 5.4% respectively, p = 0.000015, odds ratio [OR] for the R241 allele = 2.9, 95% confidence intervals [CI] = 1.7-4.8). After stratifying for age of disease onset, the R241 variant mainly conferred predisposition to CD occurring during adulthood (OR = 4.2, 95% CI = 2.3-7.5, Pc = 0.000004 for adulthood-onset CD vs. R = 2.1, 95%, CI = 1.2-3.9, Pc = 0.0047 for childhood-onset CD). Position 241 of ICAM-1 maps to the binding site for the integrin Mac-1 and might modify the strength of interaction between endothelium and immune cells. If confirmed in independent datasets, these results may be of importance in at-risk individuals to distinguish rapid from delayed progression to clinical CD.

Adolescent↗
PubMed2006

Study of the impact of liver transplantation on the outcome of intestinal grafts in children.

BACKGROUND: Successful small bowel transplantation remains a challenge due to the septic and immune content of the gut. The possible beneficial role of the liver was assessed in pediatric recipients of isolated intestinal and liver intestinal combined transplantation, receiving the same immunosuppressive therapy. METHODS: Fifteen children who underwent small bowel transplantation (seven SbTx) or combined liver-small bowel transplantation (eight LSbTx) at a single center between 1994 and 1998 were retrospectively reviewed and compared with fifteen controls (eight normal and seven appendicitis as inflammatory control). Transplant and patient survival, acute rejection episodes were analyzed and compared. Epithelial apoptotic body counts (ABC) and NF-kB (p65), Caspase-3 and Bax intestinal immunostaining from days 0 to 20 after transplantation were assessed. RESULTS: Graft and patient survivals at 5 years were respectively 75% and 75% in LSbTx; 43% and 57% in SbTx (NS). Histological analysis showed higher ABC in LSbTx intestinal mucosa (P = 0.05 on day 5, P < 0.01 thereafter). Immunostaining of biopsies on day 0 after reperfusion showed different expression of NF-kB, Caspase-3 and Bax on endothelial (P < 0.05 for NF-kB and Bax), mononuclear (P < 0.05 for Bax) and epithelial cells in LSbTx and SbTx. CONCLUSIONS: Our results suggest a protective role of the liver toward intestinal transplantation even in absence of significative difference, probably due to the small number of children. Early changes in NF-kB immunostaining in the biopsies sampled on day 0, pointed to a possible beneficial effect of the liver in the very early phase following transplantation, perhaps through the differential control of ischemia-reperfusion.

Biomarkers↗
PubMed2006

[The intestinal flora: the scales without the sword].

The intestine is colonised by a vast population of resident bacteria which have established mutualistic relationships with their host throughout evolution, progressing from commensalism to symbiotic interactions. Intestinal bacteria benefit from resources available in their host, but reciprocally provide advantages to their host, by supplying enzymatic activities not encoded in the host genome, by promoting maturation of the intestine and of the gut associated immune system as well as by modifying the host metabolism. The commensal bacteria, although deprived of pathogenic attributes, might however become a danger for the host in case of translocation, acquisition of pathogenic features or via the inappropriate activation of intestinal inflammation. Remarkably, the commensal flora promotes the onset of innate and adaptive immune defences which, in turn, allow to set up a subtle balance between the host and the flora that promotes the symbiosis.

Adult↗
PubMed2006

Implication of TNF-related apoptosis-inducing ligand in inflammatory intestinal epithelial lesions.

BACKGROUND & AIMS: Few data exist on the molecular events causing intestinal epithelial destruction during inflammatory processes, such as inflammatory bowel disease (IBD). In this work, we analyzed the potential implication of tumor necrosis factor (TNF)-related apoptosis inducing ligand (TRAIL) in these inflammatory lesions. METHODS: TRAIL and TRAIL-receptor expression were analyzed in normal, inflammatory ileum/colon and human intestinal epithelial cell (IEC) lines (HIEC), Caco-2, and HT-29 using RNase protection assay, real-time and reverse-transcription polymerase chain reaction (RT-PCR), immunohistochemistry, and Western blot analysis. TRAIL-induced activation of NF-kappaB was determined by electrophoretic mobility shift assay. Caspase-recruitment domain (CARD)15 expression and interleukin-(IL)8 production were studied by RT-PCR and enzyme-linked immunosorbent assay. Apoptosis was monitored using Annexin-V/caspase-3 assays. RESULTS: Normal mature IEC expressed low TRAIL levels, whereas, in inflammatory lesions, TRAIL messenger RNA and protein were markedly up-regulated in IEC and lamina propria lymphocytes at levels comparable with trinitrobenzene sulfonic acid-induced colitis. Interferon-gamma and TNF-alpha potently induced TRAIL in IEC. In vitro analyses revealed a dual biologic effect of TRAIL on HIEC: Under noninflammatory conditions, TRAIL up-regulated via nuclear factor-kappaB CARD15 and IL-8, whereas, under inflammatory conditions, TRAIL became a potent inducer of apoptosis in HIEC, which was confirmed ex vivo using ileal organ cultures. TNF-alpha markedly increased the expression of the proapoptotic receptor TRAIL-R2. TRAIL-induced IEC apoptosis required a functional caspase cascade. CONCLUSIONS: TRAIL is a new inflammatory mediator implicated in the homeostasis of intestinal epithelial barrier functions. TRAIL is highly up-regulated in IEC in inflammatory ileum and colon. It may augment in an auto-/paracrine fashion the elimination of IEC via apoptosis.

Animals↗
PubMed2006

Stimulation of immunity without alteration of oral tolerance in mice fed with heat-treated fermented infant formula.

OBJECTIVES: Little information is available on the properties of fermented milk formula intended to healthy infants. This study analyzes the effect of long-term ingestion of a heat-treated, fermented milk formula on the development of oral tolerance or systemic immune response to soluble antigens in mice. MATERIALS AND METHODS: The C3H/HeN mice, fed with a heat-treated fermented (Bifidobacterium breve C50 and Streptococcus thermophilus 065) infant formula (htFF) or a matched control diet (control), were immunized with ovalbumin (OVA) with or without gavage of 20 mg OVA to induce tolerance or immunity, respectively. Systemic and local anti-OVA immune responses and intestinal barrier function were measured after 5 to 6 weeks. RESULTS: Oral tolerance to OVA developed similarly in htFF- and control-fed mice, attested to by the downregulation of OVA-specific immunoglobulin (Ig) G and IgE after oral OVA administration. In contrast, immunization with OVA led to significantly higher titers in htFF-fed mice than in control-fed mice (log2 IgG titers, 16.45 +/- 1.24 and 15.46 +/- 0.79, respectively; P = 0.012). Jejunal interferon gamma, interleukin 12p40 and interleukin 10 expressions were significantly higher in tolerized mice fed with htFF compared with those fed with the control diet. Mucosal to serosal intact horseradish peroxidase fluxes were lower in htFF-fed mice than in control-fed mice (39 +/- 8 and 118 +/- 38 ng/h x cm2, respectively; P < 0.0001), indicating that the htFF diet reinforces intestinal barrier capacity to macromolecules. CONCLUSIONS: In mice, htFF strengthens intestinal barrier and enhances systemic immune responses to antigens without interfering with the development of oral tolerance, suggesting a potential beneficial effect in host defence and vaccination.

Administration, Oral↗
PubMed2005

The mucosal immune system: from control of inflammation to protection against infections.

The IV meeting of the European Mucosal Immunology Group, held October 8-10, 2004, in Lyon, gathered fundamental and clinical research scientists to discuss the most recent updates on basic and clinical aspects of mucosal immunology. The meeting was focused on innate and acquired immune mechanisms underlying handling and immune recognition of commensals, allergens, and pathogens by the mucosal immune system and its outcome in health and disease as well as for vaccine development. The scientific program featured five topics of growing interest for fundamental research scientists and clinicians, including the role of commensal bacteria in mucosal immunity; function of dendritic cells in infection, inflammation, and tolerance; control of mucosal inflammation by regulatory T cells; novel routes and adjuvants for mucosal vaccines; and mucosal immunity against HIV infection and vaccination strategies.

Animals↗
PubMed2005

Pathomechanisms in celiac disease.

Celiac disease is an inflammatory disorder of the small intestine caused by an immune response to ingested wheat gluten and similar proteins of rye and barley. It affects at least 1 in 200 individuals, corresponding to roughly three million patients in Western Europe and Northern America alone. Data accumulated since the discovery of gluten specific T cells in the intestine of celiac disease patients the early 1990s have allowed the deciphering of the interplay between the triggering environmental factor, gluten, the main genetic risk factor, the HLA-DQ2/8 haplotypes and the autoantigen; the enzyme tissue transglutaminase (tTG). This established a key role of adaptive immunity orchestrated by lamina propria T cells responding to a set of gluten derived peptides. More recent work points to an important contribution of innate immunity triggered by a distinct gluten peptide and driven by the proinflammatory cytokine Interleukine-5 (IL-15). Together, these observations provide a unique explanation for the disease inducing capacity of gluten.

Celiac Disease↗
PubMed2005

Enhanced in situ expression of NF-kappaBp65 is an early marker of intestinal graft rejection in rats.

BACKGROUND: Although intestinal transplantation provides a unique situation of free access to the graft because of the presence of temporary enterostomas, evaluation of local immunosuppression is still an unresolved issue and may constitute one of the causes of grafting failure. AIMS: To study in a rat model of allogeneic intestinal transplantation the expression of transcription factors involved in lymphocyte activation in situ in the graft and to identify factors reflecting the efficiency of drug immunosuppression. METHODS: Intestinal transplantation was performed in a Brown Norway (RT1n-donors)-Lewis (RT1(l)-recipients) rat strain combination. The animals were treated with tacrolimus to induce tolerance or left untreated. Syngeneic intestinal grafts and intestine from donor rats with peritonitis were used as controls. NF-kappaBp65, p-c-Jun, interleukin 2 receptor (CD25), and major histocompatibility complex class II antigen (OX-6) expression was studied in graft biopsies on days 2 and 5 by immunohistochemistry. RESULTS: On day 2, before the onset of histologic signs of rejection, the number of cells expressing NF-kappaBp65 in the pericryptic lamina propria was significantly higher in untreated recipients of allogeneic grafts than in the other groups (P = .009). NF-kappaBp65 expression then fell between days 2 and 5 (P = .009). Classic markers of T-cell activation (CD25 and OX-6) were expressed during rejection in the lamina propria and on crypt enterocytes, respectively. p-c-Jun expression did not differ among the 3 groups. CONCLUSION: NF-kappaBp65 expression in intestinal grafts is a precocious sign of local activation during rejection and could thus serve to optimize the management of immunosuppressive therapy.

Animals↗
PubMed2005

Limited efficiency of prolyl-endopeptidase in the detoxification of gliadin peptides in celiac disease.

BACKGROUND & AIMS: The resistance of prolamines to digestive enzymes is thought to be a key contributor to the pathogenesis of celiac disease by promoting the intestinal entrance of peptides able to trigger inflammation in at-risk individuals. Oral administration of a bacterial prolyl-endopeptidase (PEP) therefore was proposed as a treatment for celiac disease. To delineate the feasibility of this treatment, the effect of PEP on gliadin peptides was assessed in vitro, and ex vivo during their transport across intestinal biopsy specimens of active celiac disease patients. METHODS: In vitro degradation by PEP of 3H-labeled gliadin peptides 56-88 (33-mer) and 31-49, was analyzed by radio-reverse-phase high-performance liquid chromatography and mass spectrometry. For ex vivo studies, PEP and 3H-peptides were added together onto the mucosal side of duodenal biopsy specimens mounted in Ussing chambers, and peptide transport and digestion were assessed by radio-reverse-phase high-performance liquid chromatography. RESULTS: Gliadin peptides were degraded partly by 20 mU/mL PEP both in vitro and ex vivo. This concentration of PEP decreased the amount of intact peptides 31-49 and 56-88 crossing the intestinal biopsy specimens of celiac disease patients, but could not prevent the intestinal passage of toxic or immunostimulatory metabolites. PEP concentrations of at least 500 mU/mL for 3 hours were required to achieve full detoxification of peptides and to prevent intestinal transport of active fragments. CONCLUSIONS: After prolonged exposure to high concentrations of PEP, the amount of immunostimulatory gliadin peptides reaching the local immune system in celiac patients is decreased. These results provide a basis to establish whether such conditions are achievable in vivo.

Biopsy↗
PubMed2004

Fetal intestinal obstruction induces alteration of enteric nervous system development in human intestinal atresia.

Intestinal motility disorders are a major cause of morbidity after surgical repair of intestinal atresia of unknown mechanism. We hypothesized that interruption of antenatal peristalsis may disturb the normal development of the enteric nervous system. Using a series of neuronal (synaptophysin, neuronal nitric oxide synthase, neurofilaments) and nonneuronal markers (glial acidic fibrillary protein and c-Kit) and immunohistochemistry, we have defined developmental steps of the enteric nervous system in normal intestine (12 fetuses, 15 children, and 4 adults) and their alterations above and below the obstacle in 22 human intestinal atresia compared with age-matched controls. Antisynaptophysin antibody revealed the progressive conversion of the myenteric plexus from a continuous belt into regularly spaced ganglions during normal fetal gut development and, by contrast, the significantly delayed appearance of individual neuronal ganglions in the distal segments of atresia (p < 0.05). Staging using three other markers for neuronal (neurofilaments and neuronal nitric oxide synthase) and nonneuronal cells (glial acidic fibrillary protein) confirmed that maturation of the myenteric plexus was significantly delayed below atresia (p < 0.01). These results indicate that intestinal atresia impairs the development of the enteric nervous system and provide an anatomical substrate for the motility disorders observed after surgical repair. They point to the role of peristalsis in normal gut development and suggest that stimulation of peristalsis might be used to accelerate recovery.

Biomarkers↗
PubMed2004

Food allergens are protected from degradation during CD23-mediated transepithelial transport.

BACKGROUND: CD23 (FcepsilonRII) is expressed by intestinal epithelial cells (IEC) following allergic stimulation and increases the uptake of IgE/allergen complexes. The aim of this study was to further analyze the role of CD23 in the intraepithelial processing of food allergens during transepithelial transport. METHODS: Balb-C mice were sensitized intraperitoneally with horseradish peroxidase (HRP) or beta-lactoglobulin (beta-LG) in the presence of pertussis toxin. In control and sensitized mice, 3H-HRP, intact HRP, or 14C-beta-LG fluxes were measured across jejunal segments mounted in Ussing chambers, in the presence or absence of mucosal anti-CD23 antibodies. HPLC analysis of serosal buffer was performed to detect HRP- or beta-LG-derived radiolabelled metabolites generated during transepithelial transport. RESULTS: In HRP-sensitized mice, 3H-HRP fluxes and intact HRP fluxes (3,836 +/- 476 and 290 +/- 86 ng/h x cm2, respectively) were significantly increased compared to control mice (1,677 +/- 297 ng/h x cm2, p < 0.01, and 106 +/- 23 ng/h x cm2, p < 0.02, respectively). HPLC analysis indicated the presence of intact HRP in the serosal compartment already 10 min after addition of HRP to the mucosal compartment, a result not observed in the control mice. In the presence of anti-CD23 antibodies, intact HRP fluxes were significantly decreased (131 +/- 27 ng/h x cm2) compared to control values in sensitized mice (290 +/- 86 ng/h x cm2, p < 0.02), suggesting that CD23 is involved is this 'protected' transport pathway. A similar protection during intestinal transport was observed for beta-LG in beta-LG sensitized mice. CONCLUSIONS: These results confirm that CD23 is involved in the rapid transepithelial transport of intact allergens in sensitized animals, and indicate that CD23 opens a 'protected' transport pathway in IECs.

Allergens↗
PubMed2004

In vitro and ex vivo activation of the TLR5 signaling pathway in intestinal epithelial cells by a commensal Escherichia coli strain.

The capacity of non-pathogenic enteric bacteria to induce a pro-inflammatory response is under debate in terms of its effect on the symbiosis between the mammalian host and its commensal gut microflora. Activation of NF-kappaB and induction of interleukin-8 (IL-8) and CCL-20 by the commensal Escherichia coli strain MG1655 were first studied in vitro in the human intestinal epithelial cell (IECs) lines HT29-19A and Caco-2, transfected or not with plasmids encoding dominant negative Toll-like receptor (TLR) 5 and myeloid differentiation factor-88 (MyD88) adaptor protein. The response of enterocytes in situ was then assessed using murine ileal biopsies mounted in Ussing chambers. Commensal E. coli induced NF-kappaB DNA binding, NF-kappaB transcriptional activity, CCL-20 expression, and IL-8 secretion in the human IEC lines. E. coli MG1655 flagellin was necessary and sufficient to trigger this pro-inflammatory pathway via its interaction with TLR5 and the subsequent recruitment of the adaptor protein MyD88. Following epithelial cell polarization, signaling could be induced by live E. coli and flagellin on the apical side of HT29-19A. The in vivo relevance of our findings was confirmed, because immunohistochemical staining of murine ileum demonstrated expression of TLR5 in the apical part of enterocytes in situ. Furthermore, flagellin added on the mucosal side of murine ileal biopsies mounted in Ussing chambers induced a basolateral production of KC, a functional murine homolog of human IL-8. These findings provide strong evidence that flagellin released by flagellated commensal bacteria in the intestinal lumen can induce a pro-inflammatory response in enterocytes in vivo.

Adaptor Proteins, Signal Transducing↗
PubMed2004

A direct role for NKG2D/MICA interaction in villous atrophy during celiac disease.

MICA molecules interact with the NKG2D-activating receptor on human NK and CD8 T cells. We investigated the participation of the MICA/NKG2D pathway in the destruction of intestinal epithelium by intraepithelial T lymphocytes (IEL) in Celiac disease and its premalignant complication, refractory sprue. We show that MICA is strongly expressed at epithelial cell surface in patients with active disease and is induced by gliadin or its p31-49 derived peptide upon in vitro challenge, an effect relayed by IL-15. This triggers direct activation and costimulation of IEL through engagement of NKG2D, leading to an innate-like cytotoxicity toward epithelial targets and enhanced TCR-dependent CD8 T cell-mediated adaptive response. Villous atrophy in Celiac disease might thus be ascribed to an IEL-mediated damage to enterocytes involving NKG2D/MICA interaction after gliadin-induced expression of MICA on gut epithelium. This supports a key role for MIC/NKG2D in the activation of intraepithelial immunity in response to danger.

Atrophy↗
PubMed2003

Recurrent partial trisomy 1q22-q44 in clonal intraepithelial lymphocytes in refractory celiac sprue.

BACKGROUND & AIMS: Refractory celiac sprue, a low-grade intraepithelial lymphoma characterized by expansion of clonal intraepithelial lymphocytes with intracellular CD3 epsilon but no surface CD3-T-cell receptor complexes, can be an intermediary step between celiac disease and overt T-cell lymphoma. To gain insight into the mechanisms of lymphomagenesis in celiac disease, we have performed the first cytogenetic study in refractory celiac sprue. METHODS: Karyotypes were performed on: (1) 7 cell lines derived from clonal intraepithelial lymphocytes of patients with refractory celiac sprue; (2) 14 control T-cell lines, either from 4 of 7 patients with refractory celiac sprue or from 10 patients with uncomplicated celiac disease; and (3) bone marrow and peripheral blood lymphocytes in 1 of 7 patients with refractory celiac sprue. Rearrangements were confirmed by in situ hybridization using whole-chromosome painting probes and by comparative genomic hybridization in one patient. RESULTS: A recurrent structural chromosomal aberration leading to partial trisomy of the long arm of chromosome 1 was found in 6 of 7 cell lines from patients with refractory celiac sprue but in none of the control T-cell lines. In one patient with circulating abnormal intraepithelial lymphocytes, the partial trisomy 1q was confirmed on cells freshly isolated from bone marrow and blood. CONCLUSIONS: Refractory celiac sprue is strongly associated with partial trisomy of the 1q region. Gain of chromosome 1q, recently found in 16% of enteropathy-type T-cell lymphoma, may be an early event in lymphomagenesis related to celiac disease and provides a key to investigating molecular mechanisms of lymphoid transformation in this disease.

Adult↗