|
|
||||||||
The Journal of Immunology, Vol 150, Issue 2 399-406, Copyright © 1993 by American Association of Immunologists
ARTICLES |
SW Louie, LM Ramirez, AM Krieg, CR Maliszewski and GA Bishop
Department of Microbiology, University of Iowa, Iowa City 52242.
The CD5+ B cell lymphoma clone, CH12.LX, endogenously produces IL-4. Blocking the binding of this IL-4 to its cellular receptor inhibited the continuous proliferation of CH12.LX. mAb specific for either IL-4 or the IL-4R profoundly and specifically inhibited the proliferation of CH12.LX cells in a concentration-dependent manner, within 4 h after the addition of mAb. The addition of exogenous rIL-4 alone to CH12.LX cells had no effect on either proliferation or antibody secretion. However, exogenous rIL-4 was able to counteract the effects of anti-IL-4 antibody. Treatment of CH12.LX cells with antisense RNA oligodeoxynucleotides to IL-4 also specifically inhibited cell proliferation and decreased the levels of IL-4 secreted into the culture supernatants by more than 50%, without effect on total RNA or protein synthesis. Effects of antisense IL-4 were also blocked by addition of exogenous IL-4. Control oligodeoxynucleotides of equal size and base composition had no effect, and IL-4 antisense oligodeoxynucleotides did not effect the growth of a B cell lymphoma clone which does not produce IL-4. Blocking the binding of endogenously produced IL-4 to CH12.LX cells did not change the levels of membrane IL- 4R or CD5 molecules. However, the constitutive expression of Thy-1 by these B cells was markedly decreased, and anti-Thy-1 antibodies decreased proliferation and PMA-induced aggregation of CH12.LX cells. Autocrine secretion of IL-4 thus appears to be required both for the continuous proliferation of CH12.LX B cells, as well as their expression of Thy-1, which may function either as a homotypic adhesion molecule or a signal transduction molecule for these cells. These findings indicate that endogenously produced lymphokines may play a critical role in the maintenance of B cell hyperproliferative disorders.
This article has been cited by other articles:
![]() |
S. A. Wajeman-Chao, S. A. Lancaster, L. H. Graf Jr., and D. A. Chambers Mechanism of Catecholamine-Mediated Destabilization of Messenger RNA Encoding Thy-1 Protein in T-Lineage Cells J. Immunol., November 1, 1998; 161(9): 4825 - 4833. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |