T cell activation via the disialoganglioside GD3: analysis of signal transduction

Abstract

The monoclonal antibody (mAb) R24 is a murine immunoglobulin G3 (IgG3) that reacts with the GD3 disialoganglioside present on melanoma cells as well as a subset of T cells. R24 mAb has induced antitumor responses both alone and in combination with interleukin-2 (IL-2) in clinical trials. We have reported T cell activation via GD3 as measured by the induction of tyrosine phosphorylation. In this study a more detailed analysis of signal transduction after ligation of GD3 was performed in an attempt to understand the mechanism of in vivo therapeutic benefits observed. Analysis of subsequent events indicated that GD3 engagement resulted in phospholipase C(gamma) phosphorylation and calcium flux. When ras-associated events were examined, GD3 signaling resulted in ras activation as determined by GDP/GTP conversion as well as dose-and time-dependent IP3 activation. In addition, the majority of the IP3 activation by GD3 was inhibited by herbimycin A pretreatment. Elucidation of the nature and potential role of this moiety in GD3 signal transduction should be useful. Collectively, these data suggest a novel mechanism of T cell activation via a single, non-protein, surface moiety. This novel form of T cell-mediated activation may permit the delivery and local activation of effector cells at the tumor resulting in site-specific activation of the immune system.

Association of Src Family Tyrosine Kinase Lyn with Ganglioside GD3 in Rat Brain

“…Similar observations were reported for human peripheral T cells, where treatment with R24 led to T cell activation associated with rapid tyrosine phosphorylation of several substrates including phospholipase C␥, as well as to phosphatidylinositol turnover, calcium flux, Ras activation, cell proliferation, and cytokine secretion. The phosphatidylinositol turnover and cell proliferation can be blocked by a tyrosine kinase inhibitor (41)(42)(43), suggesting that G D3 -mediated tyrosine kinase activation has an important role in the activation of T cells. The association of Src family kinase Lyn with gangliosides has also been reported for rat basophilic leukemia RBL-2H3 cells (44 -46).…”

Comparative analysis of ganglioside conformations by MD simulations: implications for specific recognition by proteins

“…Heteronuclear ( 1 H, 13 C) NMR studies [18,19] and the use of [19]. Recently, a simple Karplus equation for trans-O-glycosidic 3 J COCC values has been developed for the conformational analysis of carbohydrates [23]. In the past, NMR studies, in combination with molecular mechanics calculations have been used to determine the solution structure of GM3 [24], GD1a [25], GM1, GM1b, GD1a [26], GM1 [27,28] and GD1a [29±31].…”

Cholera toxin, LT-I, LT-IIa and LT-IIb: the critical role of ganglioside binding in immunomodulation by Type I and Type II heat-labile enterotoxins

“…Crosslinking of ganglioside GD3 (GD3) with an anti-GD3 monoclonal antibody induced proliferation of T cells, secretion of interferon-γ (IFN-γ) and interleukin-6 (IL-6), and increased expression of HLA class II molecules and interleukin-2 (IL-2) receptors [37][38][39]. Hammond et al [16] hypothesized that clustering of a small number of lipids in a cell's membrane potentially could reorganize many other membrane components in a rapid manner.…”