PMN-derived proteases enhance the affinity of Fcγ receptor II on myeloid cells, but not on B cells

Tuijnman, Wouter B.; Dam, Frans W. Van; Winkel, Jan G. J. van de; Capel, P. J. A.

doi:10.1016/0161-5890(90)90026-v

Cited by 6 publications

(6 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A remarkable detail is that, whereas leucocyte elastase could enhance EA-mlgG2b rosetting, pancreatic elastase was unable to do so. A similar observation was made previously when the effect of proteolytie enzymes on EA-mlgGI rosetting of human niyeloid cell lines was studied [19]. This may be due to diBerences in the fine specificity of these two elastase enzymes [28].…”

Section: Discussionsupporting

confidence: 75%

“…As a matter of fact, the binding of human IgGl was enhanced over that seen with untreated cells [16], In studies that were performed many years later, when much more was known about the dilTerent classes of Fc receptors for IgG, we could demonstrate that proteolysis had no effect on human monocyte FcyRI, whereas the affinity of human monocyte FcyRII for IgG was strongly increased by the proteolytie enzymes trypsin and pronase. The number of FcyRII molecules was not affected [17, IX], Similar results were obtained with human leucocyte elastase [19]. An increased EA rosetting of human monocytes has also been observed after treating the monocytes with neuraminidase, an enzyme that has no proteolytie activity but that can remove sialic acid from sialoglycoproleins [20].…”

Section: Introductionsupporting

confidence: 53%

See 1 more Smart Citation

Proteolysis Increases the Fc‐Mediated Binding of Murine IgG2b to Human EBV‐Transformed B Cells, but Decreases the Expression of FcγRII and FcγRII

et al. 1993

View full text Add to dashboard Cite

We have previously described a polymorphic human Fc receptor for murine IgG2b (mIgG2b). This receptor was defined by the binding of (complexed) mIgG2b to monocytes and Epstein-Barr virus (EBV)-transformed B cells. Three per cent of normal individuals were high responders with respect to mIgG2b (mIgG2b-HR), whereas the other individuals were low responders for mIgG2b (mIgG2b-LR). In the present study we investigated the effect of proteolytic enzymes on the Fc-mediated binding of mIgG2b to EBV-B cells. Pronase, human leucocyte elastase and cathepsin G caused an increased binding (in an EA-rosetting assay) of mIgG2b to EBV-B cells from mIgG2b-HR, but not from mIgG2b-LR. Simultaneous immunofluorescence studies demonstrated that these proteolytic enzymes strongly reduced the expression of Fc gamma RII and Fc epsilon RII on these cells, whereas HLA class I or HLA class II molecules were not affected. These findings strongly suggest that binding of mIgG2b is not mediated by Fc gamma RII or Fc epsilon RII. We also studied the effect of proteolysis on mIgG2b-HR EBV-B cells from an HLA class II-negative individual. In this case EA-mIgG2b rosetting was decreased after proteolysis, suggesting that HLA class II molecules may have a role in protecting the binding site for mIgG2b against proteolytic destruction.

show abstract

Section: Discussionsupporting

confidence: 75%

Section: Introductionsupporting

confidence: 53%

Proteolysis Increases the Fc‐Mediated Binding of Murine IgG2b to Human EBV‐Transformed B Cells, but Decreases the Expression of FcγRII and FcγRII

et al. 1993

View full text Add to dashboard Cite

show abstract

“…IIaIIa were able to phagocytose opsonized SRBC, consistent with previous reports that human Fc␥RIIa can mediate phagocytosis in heterologous systems (42,43). Overall, these data indicated that chimeric Fc⑀RI molecules were capable of effector function in the absence of endogenous CD3 or Fc⑀RI␥ signaling molecules.…”

Section: Iiasupporting

confidence: 90%

“…These data paralleled similar experiments by Hutchinson et al (36) that prepared chimeras of Fc␥RI. Human Fc␥RIIa has been reported to mediate phagocytosis in two different heterologous systems, 3T6 and COS-1 fibroblasts (42,43). In the first of these studies, removal of the cytoplasmic tail of human Fc␥RIIa abolished phagocytosis implying that this domain contains the phagocytic signal.…”

Section: Iiamentioning

confidence: 99%

Redirected Cytotoxic Effector Function

Kershaw

Darcy

Hulett

et al. 1996

Journal of Biological Chemistry

View full text Add to dashboard Cite

“…We next assessed IgG complex binding to neutrophils treated with human neutrophil elastase (HNE), which has been previously shown to regulate several effector functions, including CD32-mediated IgG complex binding (36). We have determined the contribution of the two types of Fc␥R (CD32 and CD16; Fig.…”

Section: Elastase-mediated Augmentation Of Igg Binding To Neutrophilsmentioning

confidence: 99%

Association of FcγRIIa (CD32a) with Lipid Rafts Regulates Ligand Binding Activity

Bournazos

Hart²,

Chamberlain

et al. 2009

The Journal of Immunology

View full text Add to dashboard Cite

Binding of Igs to myeloid cells via FcR is a key event in the control of innate and acquired immunity. FcγRIIa (CD32a) is a receptor for multivalent IgG expressed predominantly by myeloid cells, and its association with microdomains rich in cholesterol and sphingolipids, termed as lipid rafts, has been reported to be essential for efficient signaling. However, for many myeloid cell types, ligand binding to CD32a is suppressed by as yet undefined mechanisms. In this study, we have examined the role of CD32a-lipid raft interactions in the regulation of IgG binding to CD32a. Disruption of lipid raft structure following depletion or sequestration of membrane cholesterol greatly inhibited CD32a-mediated IgG binding. Furthermore, specific CD32a mutants, which show reduced association with lipid rafts (A224S and C241A), displayed decreased levels of IgG binding compared with wild-type CD32a. In contrast, constitutively lipid raft-associated CD32a (GPI-anchored CD32a) exhibited increased capacity for IgG binding compared with the full-length transmembrane CD32a. Our findings clearly suggest a major role for lipid rafts in the regulation of IgG binding and, more specifically, that suppression of CD32a-mediated IgG binding in myeloid cells is achieved by receptor exclusion from lipid raft membrane microdomains.

show abstract

PMN-derived proteases enhance the affinity of Fcγ receptor II on myeloid cells, but not on B cells

Cited by 6 publications

References 27 publications

Proteolysis Increases the Fc‐Mediated Binding of Murine IgG2b to Human EBV‐Transformed B Cells, but Decreases the Expression of FcγRII and FcγRII

Proteolysis Increases the Fc‐Mediated Binding of Murine IgG2b to Human EBV‐Transformed B Cells, but Decreases the Expression of FcγRII and FcγRII

Redirected Cytotoxic Effector Function

Association of FcγRIIa (CD32a) with Lipid Rafts Regulates Ligand Binding Activity

Contact Info

Product

Resources

About