Effect of cytokine and antigen stimulation on peripheral blood lymphocyte syndecan-1 expression.
BACKGROUND
Cytokines are not only produced by activated lymphocytes but also interact with a number of cell-surface molecules on the same cells. Syndecan-1 is one such cell-surface molecule, which has the capacity to bind a variety of growth factors as well as cytokines. The aim of this study was to examine the effects of transforming growth factor beta (TGF-beta), interleukin-1 (IL-1), IL-2, IL-4, lipopolysaccharide (LPS) from Porphyromonas gingivalis and tetanus toxoid on syndecan-1 expression by B and T lymphocytes.


METHODS
B and T lymphocytes were obtained from the peripheral blood of healthy donors. Following exposure to the above growth factors, cytokines and antigens, syndecan-1 expression was determined by flow cytometry.


RESULTS
Subjects could be categorized as high or low expressors of syndecan-1. In the high-responder group TGF-beta1 alone resulted in a significant increase in syndecan-1 expression by both B and T cells. None of the other cytokines and antigens produced a significant response. When analysed in combination, TGF-beta1 in combination with IL-2, IL-4, P. gingivalis LPS and tetanus toxoid all produced significant increases in syndecan-1 expression by B cells. For T cells, combinations of TGF-beta1 with IL-2 and tetanus toxoid resulted in increased syndecan-1 expression.


CONCLUSIONS
Both B and T lymphocytes synthesize the cell-surface proteoglycan syndecan-1 and its expression can be modulated by TGF-beta1, either alone or in combination with IL-2, IL-4 and LPS from P. gingivalis and tetanus toxoid. While these may reflect general responses under inflammatory conditions their biological significance requires further investigation.
Manakil
J F
JF
Department of Dentistry, University of Queensland, Brisbane, Qld, Australia.
Seymour
G J
GJ
Bartold
P M
PM
D000328:Adult; D000704:Analysis of Variance; D000942:Antigens, Bacterial / Q000494:pharmacology*; D002478:Cells, Cultured; D016207:Cytokines / Q000494:pharmacology*; D004338:Drug Combinations; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D011994:Recombinant Proteins / Q000494:pharmacology; D012044:Regression Analysis; D053668:Syndecan-1 / Q000096:biosynthesis*; D053773:Transforming Growth Factor beta1 / Q000494:pharmacology*
D000942:Antigens, Bacterial; D016207:Cytokines; D004338:Drug Combinations; D011994:Recombinant Proteins; D053668:Syndecan-1; D053773:Transforming Growth Factor beta1