TY - JOUR
T1 - Selection of T cell receptor expression mutants through the functionally linked Ly-6A
AU - Sugiyama, Eiji
AU - Cantagrel, Alain
AU - Reno, Toufic
AU - Stafford-Brady, Frances
AU - Yeh, Edward T.H.
AU - Bonventre, Joseph V.
N1 - Funding Information:
’ This work was supported by NIH Grants AR-03564, DK-39773, DK-38452, and DK-38165. Edward T. H. Yeh is a recipient of an Arthritis Investigator Award and a Upjohn Scholar Award. Joseph Bonventre is an Established Investigator from the American Heart Association. * Abbreviations used: TAP, T-cell activating protein; MHC, major histocompatibility complex; mAb, monoclonal antibody; PIP*, phosphatidylinositol 4,5-bisphosphate; IL-2, interleukin-2; GPI, glycosylphosphatidylinositol; EMS, ethylmethane sulfonate; PMA, phorbol myristate acetate; c-OVA, chicken ovalbumin.
PY - 1990/10/15
Y1 - 1990/10/15
N2 - Ly-6A is a glycosyl-phosphatidylinositol (GPI)-anchored molecule that participates in murine T cell activation. Activation of T cell hybridomas with anti-Ly-6A monoclonal antibody (mAb) leads to production of interleukin-2 (IL-2), but also to a paradoxical growth inhibition, which was used to select for signaling mutants. Fifteen subclones derived from two independent mutageneses and anti-Ly-6A selection were characterized. Thirteen subclones responded poorly or not at all to soluble anti-Ly-6A mAb. Although the selective pressure was exerted through Ly-6A, only one mutant did not express the Ly-6A antigen. Interestingly, 10 of the 15 subclones expressed either nondetectable or a very low level of T cell receptor/CD3 complex (TCR/CD3). Preferential expansion of TCR/CD3 expression mutants following anti-Ly-6A selection further established functional linkage between Ly-6A and TCR/CD3 complex. The mechanism of the functional coupling was investigated by analyzing the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2), one of the early events in T cell activation. We showed that PIP2 was not hydrolyzed in response to anti-Ly-6A in TCR/CD3-negative mutants. Aluminum fluoride, which activates G protein directly, did induce PIP2 hydrolysis in these cells. These data suggest that activation signals originated from Ly-6A must be transmitted first to TCR/CD3 complex, which then couples to the G protein/phospholipase C system. A similar requirement also applies to the Thy-1 protein and lectin receptors. Thus, the TCR/CD3 complex plays a central role in the integration and transmission of activation signals that originated from several T cell surface molecules.
AB - Ly-6A is a glycosyl-phosphatidylinositol (GPI)-anchored molecule that participates in murine T cell activation. Activation of T cell hybridomas with anti-Ly-6A monoclonal antibody (mAb) leads to production of interleukin-2 (IL-2), but also to a paradoxical growth inhibition, which was used to select for signaling mutants. Fifteen subclones derived from two independent mutageneses and anti-Ly-6A selection were characterized. Thirteen subclones responded poorly or not at all to soluble anti-Ly-6A mAb. Although the selective pressure was exerted through Ly-6A, only one mutant did not express the Ly-6A antigen. Interestingly, 10 of the 15 subclones expressed either nondetectable or a very low level of T cell receptor/CD3 complex (TCR/CD3). Preferential expansion of TCR/CD3 expression mutants following anti-Ly-6A selection further established functional linkage between Ly-6A and TCR/CD3 complex. The mechanism of the functional coupling was investigated by analyzing the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2), one of the early events in T cell activation. We showed that PIP2 was not hydrolyzed in response to anti-Ly-6A in TCR/CD3-negative mutants. Aluminum fluoride, which activates G protein directly, did induce PIP2 hydrolysis in these cells. These data suggest that activation signals originated from Ly-6A must be transmitted first to TCR/CD3 complex, which then couples to the G protein/phospholipase C system. A similar requirement also applies to the Thy-1 protein and lectin receptors. Thus, the TCR/CD3 complex plays a central role in the integration and transmission of activation signals that originated from several T cell surface molecules.
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U2 - 10.1016/0008-8749(90)90270-2
DO - 10.1016/0008-8749(90)90270-2
M3 - Article
C2 - 1976441
AN - SCOPUS:0025013358
SN - 0008-8749
VL - 130
SP - 271
EP - 280
JO - Cellular Immunology
JF - Cellular Immunology
IS - 2
ER -