D. Hauzenberger et al., Spectrum of extracellular matrix degrading enzymes in normal and malignantT lymphocytes, ANTICANC R, 19(3A), 1999, pp. 1945-1952
Human T cells produce and release fibronectin degrading neutral serine prot
eases with a molecular weight of 50 kD, 70-80 kD (doublet) and 95 kD and ha
ve a cell associated 400 kD fibronectin degrading enzyme. In addition, huma
n T cells produce proteases with m.w. 50 70-80 kD and 400 kD which degrade
laminin. CD 4+ T lymphocytes from a non-malignant cloned human T cell line
produce a 92 kD gelatinase (MMP 9) and malignant T cell lines release, in a
ddition to the 92 kD gelatinase, low amounts of a 72 kD gelatinase (MMP 2).
Purification of the enzymatic activities using benzamidine sepharose yield
s a 50 kD and a 70 kD band of which the 50 kD band has fibronectin degradin
g capacity. The purified enzymes do not react with monoclonal antibodies to
various previously characterized proteolytic enzymes present in T cells. T
lymphocytes from a non-malignant cloned human T cell line produce high amo
unts of the 50 and 70-80 kD proteases directly after stimulation with anti-
CD 3 monoclonal antibodies wherafter the production of these enzymes declin
es with time. The expression of the 400 kD fibronectin-degrading protease i
s downregulated by crosslinking of alpha 4 beta 1-integrin receptors on T c
ells using monoclonal antibodies. Thus, T lymphocytes produce several matri
x degrading enzymes with multiple substrate specificities. The expression o
f these enzymes is controlled partly by lymphocyte activation signals or by
direct signalling via beta 1-integrins.