Differential signal requirements in T-cell activation by mitogen and superantigen
| Autor: | M A Tomai, Malak Kotb, Edwin H. Beachey, Gipsy Majumdar |
|---|---|
| Rok vydání: | 1990 |
| Předmět: |
T-Lymphocytes
T cell Antigen-Presenting Cells Stimulation Biology Lymphocyte Activation Jurkat cells chemistry.chemical_compound Bacterial Proteins Antigen Tumor Cells Cultured medicine Superantigen Humans Phytohemagglutinins Receptor Antigens Bacterial Interleukin-6 Interleukin Receptors Interleukin-2 Cell Biology Molecular biology Peptide Fragments medicine.anatomical_structure chemistry Biochemistry Phorbol Cytokines Interleukin-2 Tetradecanoylphorbol Acetate Calcium Mitogens Carrier Proteins Bacterial Outer Membrane Proteins Interleukin-1 |
| Zdroj: | Cellular Signalling. 2:521-530 |
| ISSN: | 0898-6568 |
| Popis: | The requirement for co-stimulatory molecules in T-cell stimulation by mitogens and superantigens in the absence of antigen-presenting cells (APC) was investigated. Phytohemagglutinin (PHA) induced interleukin (IL)-2 receptor (IL-2R) expression on purified T-cells, but proliferation occurred only when exogenous IL-2 was added. In contrast, the proliferative response to a pepsin-extracted type 5 M-protein from Streptococcus pyogenes (pep M5), a recently identified superantigen, required signals provided by phorbol 12-myristate 13-acetate (PMA), IL-1 and IL-6. pep M5 alone did not induce IL-2R expression; however, when combined with PMA, IL-1 and IL-6, IL-2R was expressed. Differences were also observed in the response of the leukemic T-cell line, Jurkat, to PHA and pep M5. Soluble PHA, but not pep M5, induced IL-2 production by these cells in the presence of PMA. Cross-linking by its specific antibody or adsorption of pep M5 to microtiter plates was required to activate Jurkat cells. Both PHA and pep M5 induced Ca2+ mobilization in Jurkat cells; however, only PHA induced a rise in intracellular Ca2+ in purified T-cells, whereas pep M5 was unable to induce this activity unless IL-1, IL-6 and PMA were added. Our data provide biochemical evidence that mitogenic and superantigenic stimulation of T-cells is different. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|