Jp. Rodriguez et al., THE SULFATION DEGREE OF MEMBRANE-ASSOCIATED PROTEOGLYCAN FROM A HEMATOPOIETIC-CELL LINE IS DETERMINED BY CHANGES THE GROWTH-STATE OF THE CELL, European journal of cell biology, 67(3), 1995, pp. 261-266
Multipotential hemopoietic progenitor cells (FDCP-mix) proliferate in
culture medium supplemented with horse serum. When transferred to a me
dium without serum, cells do not proliferate and enter a quiescent sta
te. Both proliferative and quiescent cells synthesize only chondroitin
sulfate proteoglycan (CS-PG) which is associated to the cell membrane
. Incorporation of (SO4)-S-35 info CS-PG was 4-fold higher in quiescen
t than in proliferative cells. Flow cytometric studies using monoclona
l antibodies which recognize the core protein or the CS chains, showed
that the increased uptake of sulfate was not the consequence of an in
crease in the abundance of CS-PG. Further characterization demonstrate
d that CS-PG isolated from quiescent cells exhibited a slightly higher
hydrodynamic size than CS-PG from proliferative cells. However, the g
lycosaminoglycan chains from PG derived from proliferative and quiesce
nt cells have the same hydrodynamic size. Through ion-exchange chromat
ography we observed that the mean charge density of PG from quiescent
cells was higher than in proliferative cells, suggesting a higher sulf
ation degree from PG synthesized by quiescent cells. This was confirme
d by now cytometric studies using monoclonal antibody 2B6, which recog
nizes the unsaturated terminal disaccharide of chondroitin-4-O-sulfate
.