These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Soluble CD16/Fc gamma RIII induces maturation of dendritic cells and production of several cytokines including IL-12.
    Author: de la Salle H, Galon J, Bausinger H, Spehner D, Bohbot A, Cohen J, Cazenave JP, Fridman WH, Sautès C, Hanau D.
    Journal: Adv Exp Med Biol; 1997; 417():345-52. PubMed ID: 9286384.
    Abstract:
    Fc gamma RIII (CD16), a low affinity FcR which binds IgG-containing immune-complexes, exists under membrane-associated forms and under a soluble form (sFc gamma RIII). The latter, present in biological fluids (serum, saliva), is generated by proteolytic cleavage of the two membrane-associated Fc gamma RIII isoforms, Fc gamma RIII-A (expressed by macrophages and NK cells) and Fc gamma RIII-B (expressed exclusively by neutrophils). Herein we demonstrate that dendritic cells (DCs), generated by culturing monocytes with GM-CSF and IL-4, bind biotinylated recombinant sFc gamma RIII. This binding is specific and involves the complement receptor CR3 (CD11b/CD18) and CR4 (CD11c/CD18). Indeed, preincubation of DCs with anti-CD11b and anti-CD11c mAbs decreased by 52% and 62% respectively the binding with sFc gamma RIII. Moreover, electron microscopy showed that binding of gold-labeled sFc gamma RIII to DCs maintained at 4 degrees C occurred within clathrin-coated pits. Once internalized, at 37 degrees C, sFc gamma RIII entered the endocytic pathway and reached the MHC class II compartments. Furthermore, DCs incubated for 48 h with multivalent sFc gamma RIII expressed increased levels of CD40, CD80, CD86, CD54, CD58, HLA class I and class II molecules and decreased levels of CD23 and CD32. These effects result in an increased capacity of DCs to trigger proliferative responses by CD4+ CD45RA+ allogeneic T cells. RT-PCR amplification demonstrated that incubation of DCs for 20 h in the presence of multivalent sFc gamma RIII induced the appearance of GM-CSF and IL-12 p40 mRNA. Among the cytokines constitutively expressed, IL-1 beta and IL-8 were strongly up-regulated whereas IL-6 and IL-12 p35 mRNA were increased to a lesser extent and the expression of MIP-1 alpha mRNA remained constant. Finally, ELISA tests demonstrated that DCs incubated with multivalent sFc gamma RIII secreted the cytokines IL-1 beta, IL-6, IL-8, GM-CSF and IL-12 p75. Thus, while becoming internalized sFc gamma RIII could affect the capacity of DCs to present antigens and, via the induction of accessory molecules and the release of the IL-12 p75 protein, could initiate Th1 type immune response.
    [Abstract] [Full Text] [Related] [New Search]