TY - JOUR
T1 - Tumour necrosis factor-α induces morphological and functional alterations of intestinal ht29 cl.19a cell monolayers
AU - Rodriguez, P.
AU - Heyman, M.
AU - Candalh, C.
AU - Blaton, M. A.
AU - Bouchaud, C.
N1 - Funding Information:
We thank the Centre Inter-universitaire de Microscopie Electronique (CIME-Jussieu) for carrying out the electron microscopy studies. We also thank D. Raison for her excellent technical assistance. This work was supported in part by the Ministère de l’Enseignement Superieur et de la Recherche, grant n° 92G0340, by the Fondation de France grant 93-6097 and by INSERM. Pedro Rodriguez was supported by a CONICIT-BID Venezuelan scholarship.
PY - 1995/1/1
Y1 - 1995/1/1
N2 - TNF-α is a widely distributed proinflammatory cytokine, involved in many disease states. Although it has widely distributed effects, a precise mechanism of action has never been described, in particular at the epithelial level. Morpho-functional changes of the intestinal epithelial monolayer HT29 cl.19A exposed to TNF-α were therefore assessed, using electron microscopy (including freeze-fracture replica analysis), as well as measurement of mannitol, Na+ and horseradish peroxidase fluxes across intestinal HT29 cl.19A cell monolayers using Ussing chambers. TNF-α receptors were induced on HT29 cl.19A cells by a small non-toxic dose of IFN-γ (5 U/ml). After 4 h of the combined presence of TNF-α (10 ng/ml) and IFN-γ (5 U/ml), the tight junction structure was altered as shown by a significant decrease in the average strand number measured in the apico-basal direction (5.50 ± 2.70 vs 3.73 ± 1.39 in control and treated cells respectively, P < 0.0001) and by a significant decrease in junctional depth (0.27 ± 0.14 and 0.17 ± 0.10 μm in control and treated cells respectively, P < 0.0001). These results are in agreement with a decrease in number of ‗kiss‘ sites between contiguous membranes of TNF-α treated cells observed in ultrathin sections. In parallel, the paracellular permeability of intestinal monolayers increased in the presence of TNF-α compared to controls as shown by the increase in mannitol (32.4 ± 4.7 vs 9.3 ± 0.7 μg/h.cm2, P < 0.0003), Na (216 ± 27 vs 83 ± 4 μg/h.cm2, P < 0.0003) and HRP (274 ± 67 vs 34 ± 12 ng/h.cm2, P < 0.004) fluxes and by the decrease in electrical resistance (43 ± 7 vs 112 ± 10 Ω.cm2, P < 0.0001). These results indicate that, providing receptors are present. TNF-α induces an alteration of epithelial tight junctions leading to a disruption of the epithelial barrier capacity.
AB - TNF-α is a widely distributed proinflammatory cytokine, involved in many disease states. Although it has widely distributed effects, a precise mechanism of action has never been described, in particular at the epithelial level. Morpho-functional changes of the intestinal epithelial monolayer HT29 cl.19A exposed to TNF-α were therefore assessed, using electron microscopy (including freeze-fracture replica analysis), as well as measurement of mannitol, Na+ and horseradish peroxidase fluxes across intestinal HT29 cl.19A cell monolayers using Ussing chambers. TNF-α receptors were induced on HT29 cl.19A cells by a small non-toxic dose of IFN-γ (5 U/ml). After 4 h of the combined presence of TNF-α (10 ng/ml) and IFN-γ (5 U/ml), the tight junction structure was altered as shown by a significant decrease in the average strand number measured in the apico-basal direction (5.50 ± 2.70 vs 3.73 ± 1.39 in control and treated cells respectively, P < 0.0001) and by a significant decrease in junctional depth (0.27 ± 0.14 and 0.17 ± 0.10 μm in control and treated cells respectively, P < 0.0001). These results are in agreement with a decrease in number of ‗kiss‘ sites between contiguous membranes of TNF-α treated cells observed in ultrathin sections. In parallel, the paracellular permeability of intestinal monolayers increased in the presence of TNF-α compared to controls as shown by the increase in mannitol (32.4 ± 4.7 vs 9.3 ± 0.7 μg/h.cm2, P < 0.0003), Na (216 ± 27 vs 83 ± 4 μg/h.cm2, P < 0.0003) and HRP (274 ± 67 vs 34 ± 12 ng/h.cm2, P < 0.004) fluxes and by the decrease in electrical resistance (43 ± 7 vs 112 ± 10 Ω.cm2, P < 0.0001). These results indicate that, providing receptors are present. TNF-α induces an alteration of epithelial tight junctions leading to a disruption of the epithelial barrier capacity.
KW - Cytokine
KW - Electron microscopy
KW - Freeze-fracture
KW - Intestinal barrier
KW - Tight junction
UR - http://www.scopus.com/inward/record.url?scp=0028998062&partnerID=8YFLogxK
U2 - 10.1006/cyto.1995.0060
DO - 10.1006/cyto.1995.0060
M3 - 文章
C2 - 7578982
AN - SCOPUS:0028998062
SN - 1043-4666
VL - 7
SP - 441
EP - 448
JO - Cytokine
JF - Cytokine
IS - 5
ER -