|
|
||||||||
Institute of Cancer Research and Molecular Biology, The Norwegian University of Science and Technology, Trondheim, Norway
Bacterial polysaccharides have a wide range of activities in
mammals. We have studied the effect of LPS and
poly-ß-(1
4)-D-mannuronate (mannuronan, poly-M),
an exopolysaccharide from Pseudomonas aeruginosa, on the
cytotoxicity mediated by murine bone marrow cells (BMC). Addition of
LPS or mannuronan to BMC induced a time- and dose-dependent
cytotoxicity against Jurkat cells. The LPS- or mannuronan-induced
cytotoxicity was due to increased Fas ligand (FasL) expression by BMC,
since 1) Fas-transfected L1210-Fas target cells were more susceptible
to lysis than the Faslow-expressing parent L1210 cells, 2)
stimulated BMC from FasL-defective gld/gld mice were not
cytolytic and, 3) the cytolytic activity of normal BMC was inhibited by
a Fas-Fc fusion protein. Flow cytometry showed an increase in surface
FasL in LPS-stimulated BMC. RT-PCR analysis of BMC revealed
constitutive expression of FasL mRNA, which was increased after LPS
stimulation. Immunomagnetic depletion of NK1.1-, CD2-, or
CD32/16-expressing cells from BMC abrogated the LPS-induced BMC
cytotoxicity against L1210-Fas cells, suggesting that NK cells were the
cytotoxic effector cells. Depletion of CD45R/B220-, Gr-1-, or
CD11b/Mac-1-expressing cells only partially decreased BMC-mediated
cytotoxicity, and depletion of CD4- or CD8a-expressing cells had no
effect. The results support the conclusion that LPS and mannuronan
induce expression of cytotoxic FasL on bone marrow NK cells.
This article has been cited by other articles:
![]() |
A. Ruiz-Bravo, M. Jimenez-Valera, E. Moreno, V. Guerra, and A. Ramos-Cormenzana Biological Response Modifier Activity of an Exopolysaccharide from Paenibacillus jamilae CP-7 Clin. Vaccine Immunol., July 1, 2001; 8(4): 706 - 710. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. H. Flo, O. Halaas, S. Torp, L. Ryan, E. Lien, B. Dybdahl, A. Sundan, and T. Espevik Differential expression of Toll-like receptor 2 in human cells J. Leukoc. Biol., March 1, 2001; 69(3): 474 - 481. [Abstract] [Full Text] |
||||
![]() |
H. Grassmé, S. Kirschnek, J. Riethmueller, A. Riehle, G. von Kürthy, F. Lang, M. Weller, and E. Gulbins CD95/CD95 Ligand Interactions on Epithelial Cells in Host Defense to Pseudomonas aeruginosa Science, October 20, 2000; 290(5491): 527 - 530. [Abstract] [Full Text] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |