Increased proliferation, cytotoxicity, and gene expression after stimulation of human peripheral blood T lymphocytes through a surface ganglioside (GD3)
Previous studies have suggested that gangliosides have an important role in cell signaling and recognition. However, their specific function in these processes has not been clearly defined. A mAb, R24, that reacts specifically with a cell surface ganglioside (GD3) has been demonstrated to stimulate proliferation of T cells derived from human peripheral blood. In this study, we have investigated the mechanisms by which the R24 mAb affects T cell functions. We have observed that the R24 mAb stimulates GD3+ T cell proliferation, cytotoxicity, and surface marker expression of IL-2R alpha-chain, IL-2R beta-chain, HLA-DR, CD11a, and CD11c. Additionally, IFN-gamma activity but not IL-1, IL-2, or IL-4 activity was present in culture supernatants 72 h after R24 stimulation. In some donors, increased IL-6 and TNF-alpha activity also was detected after R24 treatment. Furthermore, R24 treatment resulted in translocation of c-rel, but little or no NF kappa B p50 or p65, from the cytoplasm to the nucleus and an increase of NF kappa B binding complexes containing c-rel and p50. This treatment also caused increased tyrosine phosphorylation of specific protein substrates. R24-stimulated increases in proliferation, cytotoxicity, and cell surface protein expression could be blocked by cyclosporin and staurosporin, indicating that cyclophilin/calcineurin and protein kinase C may be involved in the R24 signaling pathway. Additionally, herbimycin A, a tyrosine kinase inhibitor, blocked the R24-stimulated increase in proliferation but not cytotoxicity at concentrations consistent with specificity for tyrosine kinases. These results suggest that multiple biochemical pathways are involved in the activation of human T cells by R24.
Norihisa
Y
Y
Laboratory of Experimental Immunology, PRI/DynCorp, National Cancer Institute-Frederick Cancer Research and Development Center, MD 21702-1201.
McVicar
D W
DW
Ghosh
P
P
Houghton
A N
AN
Longo
D L
DL
Creekmore
S P
SP
Blake
T
T
Ortaldo
J R
JR
Young
H A
HA
D000591:Amino Acid Isomerases / Q000502:physiology; D000911:Antibodies, Monoclonal; D002352:Carrier Proteins / Q000502:physiology; D002451:Cell Compartmentation; D002467:Cell Nucleus / Q000378:metabolism; D003602:Cytotoxicity, Immunologic; D005732:Gangliosides / Q000502:physiology*; D015870:Gene Expression; D006801:Humans; D016130:Immunophenotyping; D066298:In Vitro Techniques; D008213:Lymphocyte Activation; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck); D008222:Lymphokines / Q000096:biosynthesis; D016328:NF-kappa B / Q000378:metabolism; D019696:Peptidylprolyl Isomerase; D011493:Protein Kinase C / Q000502:physiology; D011505:Protein-Tyrosine Kinases / Q000502:physiology; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D020569:Proto-Oncogene Proteins c-rel; D012333:RNA, Messenger / Q000235:genetics; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000276:immunology*
D000911:Antibodies, Monoclonal; D002352:Carrier Proteins; D005732:Gangliosides; D008222:Lymphokines; D016328:NF-kappa B; D011518:Proto-Oncogene Proteins; D020569:Proto-Oncogene Proteins c-rel; D012333:RNA, Messenger; C026226:ganglioside, GD3; D011505:Protein-Tyrosine Kinases; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck); D011493:Protein Kinase C; D000591:Amino Acid Isomerases; D019696:Peptidylprolyl Isomerase