What does LFA-1 bind to?
LFA-1 binds to three ligands that we have encountered before in our discussions of adhesion: ICAM-1 (CD54), ICAM-2 (CD102), and ICAM-3 (CD50) (Fig. 14-2). ICAM-1, a widely expressed membrane glycoprotein of 80–114 kDa, contains five extracellular Ig-like domains, making it another member of the Ig superfamily.
Is LFA-1 a receptor?
Consequently, the LFA-1 receptor is activated and binds to its ligand, ICAM-1, on the endothelium. Thus, the Rap1–RIAM–Talin inside-out signaling axis plays an essential role in the regulation of LFA-1 activation and adhesion strength between T cell and endothelium and subsequent migration of the T lymphocyte.
How do I activate my T cell?
The T cell encounters a dendritic cell (DC) bearing its cognate peptide in an MHC molecule, and binds the peptide-MHC though CD3 and CD4 or 8. Subsequently, co-stimulation occurs through DC-bound CD86, CD80, OX40L and 4-1BBL. This induces full activation and effector function in the T cell.
How are autoreactive cells activated?
Autoreactive T-lymphocytes behave just like “normal” ones, namely, they recognize antigenic peptides presented to them in the context of a host’s antigen presenting HLA molecule and become activated if the appropriate signals are provided.
What is another function of LFA-1 on naive T-cells?
LFA-1 and T Cell Memory Development As described above, LFA-1 plays a critical role in facilitating naïve T cell activation and differentiation through T cell-APC contacts. Indeed, defects in LFA-1/ICAM-1 interactions have been shown to lead to impairment of memory formation (122, 123).
On what types of cells can you find LFA-1?
LFA-1 is expressed in vivo on various types of leukocytes, including lymphocytes, monocytes, and dendritic cells, that can be infected by HIV. In response to antigens, chemokines, and other inflammatory stimuli, LFA-1 on these cells becomes activated and capable of binding its ICAM ligands with high affinity.
What does LFA-1 stand for?
Lymphocyte function-associated antigen-1
Lymphocyte function-associated antigen-1 (LFA-1) is a heterodimeric integrin consisting of αL (gene name, Itgal) and β2 (gene name, Itgb2) subunits expressed in all leukocytes. LFA-1 is essential for neutrophil recruitment to inflamed tissue.
What is the cell activation quirk?
Cell Activation ( 細 さい 胞 ぼう 活 かっ 性 せい , Saibō Kassei?): Katsuma’s Quirk allows him to stimulate and speed up the activity of cells in the body of anyone he touches.
What is autoreactive T cell?
Autoreactive T lymphocytes are key players in autoimmune diseases. They can act both as regulatory and effector cells. Various animal models have been used to show that the transfer of autoreactive T cells is sufficient to induce a model of an autoimmune disease.
What do autoreactive cells do?
The autoreactive compartment comprises at least two types of cells: self-reactive cells programmed during development to control the immune response as a part of a peripheral tolerance mechanism (this is the case for regulatory T-cells, Tregs), and autoreactive cells that may turn to be harmful and cause autoimmunity.
What is the role of LFA1 in T cells?
1 Department of Medicine, University of Chicago, Chicago, IL 60637, USA. The integrin LFA-1 serves as an accessory molecule in T cell activation. In addition to its well-known role as an adhesion molecule, LFA-1 can contribute to T cell activation and up-regulation of IL-2 gene expression.
Do intracellular signals drive LFA-1 activation?
Intriguingly, intracellular signals dictating LFA-1 activation are highly conserved between migration, T cell activation, and cytolytic activity suggesting that any alterations in the signaling may cause substantial biological consequences during the host immune responses.
Is LFA-1 a novel intracellular pool for asymmetric CD8+ T cell activation?
A novel intracellular pool of LFA-1 is critical for asymmetric CD8+ T cell activation and differentiation. J Cell Biol(2017) 216:3817–29.10.1083/jcb.201609072 [PMC free article][PubMed] [CrossRef] [Google Scholar]
Does LFA-1 interact with its ligand intercellular adhesion molecule 1 (ICAM-1)?
We have tested the hypothesis that LFA-1 interaction with its ligand intercellular adhesion molecule 1 (CD54) (ICAM-1) is such a costimulatory interaction in a model system using biochemically purified ICAM-1 and TCR cross-linking by anti-CD3 mAb OKT3 immobilized on plastic. Resting T cells do not respond to OKT3 mAb immobilized on plastic.