H. Hattori et al., VLA-5 IN THE PLASMA-CELL LINE, FR4DS, ACTS AS A COMMON REGULATOR OF VLA-4 AND VLA-6 IN SPREADING INDUCED BY FIBRONECTIN AND LAMININ, Cellular immunology, 174(1), 1996, pp. 63-72
VLA-B recognizes the GRGDSP sequence of fibronectin (FN) in the extrac
ellular matrix (ECM). We examined the role of beta 1 integrin in the s
preading of the human plasma cell line, FR4ds, induced by FN and lamin
in (LN). We first examined the role of VLA-5 in the spreading induced
by FN. Anti-alpha 4 antibody induced 46.4% inhibition, whereas anti-al
pha 5 had no effect. A combination of anti-alpha 4 and anti-alpha 5 en
hanced the inhibition of spreading significantly, Complementary inhibi
tion was also demonstrated using the GRGDSP peptide plus anti-alpha 4
and the GRGDNP peptide of LN plus anti-alpha 4. The results suggested
that VLA-5 is a regulator of VLA-4 and that it is involved in the reco
gnition of CRGDNP. We then examined the role of VLA-5 in the spreading
induced by LN. Anti-alpha 6 induced 53.1% inhibition. Anti-alpha 5 al
one had no effect. A combination of alpha 5 and anti-alpha 6, however,
significantly enhanced the inhibition of spreading. The combination o
f GRGDSP plus anti-alpha 6 and GRGDNP plus anti-alpha 6 resulted in co
mplete inhibition. These results suggested that VLA-5 participates in
the recognition of LN cooperatively with VLA-6 and that VLA-5 is a com
mon regulator of VLA-4 and the LN receptor, VLA-6. (C) 1996 Academic P
ress, Inc.