Abstract
Several T cell surface molecules can activate signal transduction pathways that lead to T cell activation. Like the T cell antigen receptor (TCR), several other molecules, Including the sheep erythrocyte receptor CD2, are able to activate the phosphatidylinositoi (PI) signal transduction pathway upon stimulation with appropriate agonists. However, CD2-lnitlated activation of this pathway is dependent on the functional expression of the TCR. Since the T cell does not express other known receptors that activate the PI pathway independent of the TCR, the specificity of the CD2 requirement for a functional TCR is not known. To evaluate the specificity of this requirement, we examined the functional capacity of CD2 to activate the PI pathway In a TCR-deficient cell which had been transfected with a heterologous receptor, the human muscarinic subtype 1 receptor (HM1). HM1 Is a member of the cholinergic family of receptors and is known to activate the PI pathway. HM1 can function in the absence of the TCR in a Jurkat-derived T cell host. Here we demonstrate through calcium fluorimetry and PI metabolism assays that HM1 is unable to substitute functionally for the TCR in CD2-lnltiated signal transduction. These results suggest a specific functional Interaction between CD2 and the TCR In CD2-mediated activation of the PI pathway in T cells.
Original language | English (US) |
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Pages (from-to) | 615-620 |
Number of pages | 6 |
Journal | International Immunology |
Volume | 2 |
Issue number | 7 |
DOIs | |
State | Published - Jul 1990 |
Keywords
- CD2
- Human muscarinic receptor
- Signal transduction
- TCR
ASJC Scopus subject areas
- Immunology and Allergy
- Immunology