Endothelial cells express the interleukin-1 receptor type I.
Interleukin-1 (IL-1) profoundly affects a number of functions of vascular cells. Two distinct IL-1 receptors (IL-1R) are expressed on different cell types: the 80 Kd IL-1RI on T cells and fibroblasts, and the 68 Kd IL-1RII on B cells and myelomonocytic cells. The presence and functionality of IL-1R on vascular cells has been investigated by using polyomatransformed mouse endothelial cell (EC) lines (sEnd.1 and tEnd.1). These cells expressed specific and saturable binding sites for IL-1 (1,273 sites per cell with kd 9.5 x 10(-11) mol/L for sEnd.1, and 771 sites per cell with kd 8.5 x 10(-11) mol/L for tEnd.1, with radioiodinated IL-1 alpha as ligand). Binding of IL-1 was also evident at single cell level by autoradiography. By cross-linking studies, the molecular weight of the IL-1 binding protein on EC was approximately 80 Kd. This was confirmed by the presence in EC of mRNA for the 80 Kd IL-1RI. The IL-1RI on EC was apparently functional, since EC responded to IL-1 with IL-6 mRNA expression and IL-6 bioactivity production. These results were extended to human EC and vascular smooth muscle cells, which were also found to express mRNA for IL-1RI.
Boraschi
D
D
Sclavo Research Center, Siena, Italy.
Rambaldi
A
A
Sica
A
A
Ghiara
P
P
Colotta
F
F
Wang
J M
JM
de Rossi
M
M
Zoia
C
C
Remuzzi
G
G
Bussolino
F
F
D000818:Animals; D001345:Autoradiography; D015152:Blotting, Northern; D002460:Cell Line; D004730:Endothelium, Vascular / Q000378:metabolism*; D006390:Hemangioendothelioma / Q000378:metabolism; D006801:Humans; D007375:Interleukin-1 / Q000378:metabolism*; D015850:Interleukin-6 / Q000096:biosynthesis* / Q000235:genetics; D051379:Mice; D012333:RNA, Messenger / Q000096:biosynthesis; D011971:Receptors, Immunologic / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017472:Receptors, Interleukin-1; D011994:Recombinant Proteins / Q000378:metabolism
D007375:Interleukin-1; D015850:Interleukin-6; D012333:RNA, Messenger; D011971:Receptors, Immunologic; D017472:Receptors, Interleukin-1; D011994:Recombinant Proteins