Laminin e8 alveolarization site: heparin sensitivity, putative
nonintegrin receptors and role in cell spreading.
Chen, Lanlin, Vladislav Shick, Michelle L. Matter, Susan M. Laurie,
Roy C. Ogle, and Gordon W. Laurie.
Department of Cell Biology, University of Virginia,
Charlottesville, VA, Department of Neurological Surgery, University
of Virginia, Charlottesville, VA
APStracts 3:0236L, 1996.
Cell adhesion to amino acids 2179-2198 (`SN-peptide') of the laminin-1
[alpha]1 chain is required for lung alveolar formation in vitro (M.L.
Matter and G.W. Laurie, J. Cell Biol. 124: 1083-1090, 1994). The
nature of the SN-peptide receptor(s) was probed with neutralizing
anti-integrin mabs, cells lacking integrin subunits, soluble heparin
and SN-peptide columns. Cell adhesion and spreading studies confirmed
the specificity of SN-peptide, and revealed adhesion to be unaffected
by inclusion of anti-[beta]1, anti-[alpha]2 - 6 or anti-
[alpha]v[beta]5 integrin mabs. Cells lacking [beta]1 or [alpha]6
integrin subunits were fully adherent. Adhesion was heparin - but not
chondroitin sulfate nor heparitinase - sensitive, much as is [alpha]
-dystroglycan -laminin-1 binding. Heparin eluted 155 and 180 kDa cell
surface proteins from SN-peptide columns. An additional 91 kDa
protein was eluted by EDTA. All were unrecognized by anti-[beta]1
integrin mabs. SN-peptide therefore interacts with three cell surface
proteins whose identity remains to be determined.
Received 19 August 1996; accepted in final form 15 October 1996.
APS Manuscript Number L269-6.
Article publication pending Am. J. Physiol. (Lung Cell. Mol.
Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 31 December 1996