Abstract
The lymphocyte function-associated molecule LFA-1 (CD11a/CD18) plays a key part in lymphocyte adhesion. Lymphocytes do not adhere spontaneously; activation of protein kinase C (PKC) by phorbol esters, however, gives rise to strong LFA-1-dependent adhesion, indicating that activation of LFA-1 is required to induce cell adhesion. We have now investigated whether the functionally important CD2 and CD3 surface structures on T lymphocytes are involved in the activation of LFA-1. The stimulation of these molecules, which causes activation of PKC, strongly promoted LFA-1-dependent adhesion. Furthermore, we demonstrate by using cells from an LFA-1-deficient patient that this enhanced lymphocyte adhesion is caused by activation of the LFA-1 molecule and not by activation of its ligands. LFA-1 was persistently activated by triggering through CD2 but only transiently by triggering through CD3. We postulate that CD2 and CD3 can differentially regulate the affinity of LFA-1 for its ligands by modulating its molecular conformation through PKC-dependent mechanisms.
Original language | English |
---|---|
Pages (from-to) | 811-3 |
Number of pages | 3 |
Journal | NATURE |
Volume | 342 |
Issue number | 6251 |
DOIs | |
Publication status | Published - 14 Dec 1989 |
Keywords
- Antigens, CD/physiology
- Antigens, Differentiation, T-Lymphocyte/physiology
- Antigens, Differentiation/physiology
- CD2 Antigens
- CD3 Complex
- Cell Adhesion
- Cell Adhesion Molecules/physiology
- Cells, Cultured
- Humans
- Immunologic Techniques
- In Vitro Techniques
- Lymphocyte Function-Associated Antigen-1
- Protein Kinase C/physiology
- Receptors, Antigen, T-Cell/physiology
- Receptors, Immunologic/physiology
- Receptors, Leukocyte-Adhesion/physiology
- Signal Transduction
- T-Lymphocytes/physiology