Expression of interleukin-6, leukemia inhibitory factor and their receptors by colonic epithelium and pericryptal fibroblasts.
OBJECTIVE
The cellular configuration of the human colon suggests a predetermined organization that creates specific microenvironments. The role of pericryptal fibroblasts in this microenvironment has been the subject of considerable speculation. This study examined the expression of growth factors and their receptors by colonic crypt epithelium and pericryptal fibroblasts.


RESULTS
Pericryptal fibroblast cells were isolated and cultured from decrypted human colonic mucosa. The pericryptal fibroblast cells expressed messenger RNA (mRNA) for interleukin-6 (IL-6), leukemia inhibitory factor (LIF), LIF receptor alpha, and the common coreceptor glycoprotein 130 (GP130), but not the IL-6 receptor alpha. Interleukin-6 protein expression was confirmed by the analysis of conditioned medium and immunohistochemistry. In comparison, normal colonic epithelial cells express mRNA for LIF but not IL-6 as well as the receptors for GP-130, IL-6 receptor alpha but not LIF receptor alpha. As cultures of normal human colonic epithelial cells were not available, the conditioned medium was assayed from established colon carcinoma cell lines and demonstrated a secretion of LIF but not IL-6 protein.


CONCLUSIONS
The expression of reciprocal cytokine and receptor expression suggest that there is a paracrine relationship between pericryptal fibroblasts and colonic epithelium.
Rockman
S P
SP
Division of Surgical Oncology, Peter MacCallum Cancer Institute, East Melbourne, Victoria, Australia. s.rockman@pmci.unimelb.edu.au
Demmler
K
K
Roczo
N
N
Cosgriff
A
A
Phillips
W A
WA
Thomas
R J
RJ
Whitehead
R H
RH
D015703:Antigens, CD / Q000235:genetics; D003106:Colon / Q000378:metabolism*; D003110:Colonic Neoplasms; D050822:Cytokine Receptor gp130; D005347:Fibroblasts / Q000378:metabolism; D006131:Growth Inhibitors / Q000235:genetics*; D006801:Humans; D015850:Interleukin-6 / Q000235:genetics*; D007413:Intestinal Mucosa / Q000378:metabolism*; D053605:Leukemia Inhibitory Factor; D053680:Leukemia Inhibitory Factor Receptor alpha Subunit; D008222:Lymphokines / Q000235:genetics*; D008562:Membrane Glycoproteins / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics*; D018121:Receptors, Cytokine / Q000235:genetics*; D019947:Receptors, Interleukin-6 / Q000235:genetics*; D053606:Receptors, OSM-LIF; D012016:Reference Values; D014407:Tumor Cells, Cultured / Q000378:metabolism
D015703:Antigens, CD; D006131:Growth Inhibitors; C494199:IL6ST protein, human; D015850:Interleukin-6; C507837:LIF protein, human; C507840:LIFR protein, human; D053605:Leukemia Inhibitory Factor; D053680:Leukemia Inhibitory Factor Receptor alpha Subunit; D008222:Lymphokines; D008562:Membrane Glycoproteins; D012333:RNA, Messenger; D018121:Receptors, Cytokine; D019947:Receptors, Interleukin-6; D053606:Receptors, OSM-LIF; D050822:Cytokine Receptor gp130