Limits...
IgE enhances mouse mast cell Fc(epsilon)RI expression in vitro and in vivo: evidence for a novel amplification mechanism in IgE-dependent reactions.

Yamaguchi M, Lantz CS, Oettgen HC, Katona IM, Fleming T, Miyajima I, Kinet JP, Galli SJ - J. Exp. Med. (1997)

Bottom Line: This IgE- and antigen-specific mast cell activation and mediator production is thought to be critical to the pathogenesis of allergic disorders, such as anaphylaxis and asthma, and also contributes to host defense against parasites.In turn, IgE-dependent upregulation of Fc(epsilon)RI expression significantly enhances the ability of mouse mast cells to release serotonin, interleukin-6 (IL-6), and IL-4 in response to challenge with IgE and specific antigen.The demonstration that IgE-dependent enhancement of mast cell Fc(epsilon)RI expression permits mast cells to respond to antigen challenge with increased production of proinflammatory and immunoregulatory mediators provides new insights into both the pathogenesis of allergic diseases and the regulation of protective host responses to parasites.

View Article: PubMed Central - PubMed

Affiliation: Department of Pathology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts 02215, USA.

ABSTRACT
The binding of immunoglobulin E (IgE) to high affinity IgE receptors (Fc(epsilon)RI) expressed on the surface of mast cells primes these cells to secrete, upon subsequent exposure to specific antigen, a panel of proinflammatory mediators, which includes cytokines that can also have immunoregulatory activities. This IgE- and antigen-specific mast cell activation and mediator production is thought to be critical to the pathogenesis of allergic disorders, such as anaphylaxis and asthma, and also contributes to host defense against parasites. We now report that exposure to IgE results in a striking (up to 32-fold) upregulation of surface expression of Fc(epsilon)RI on mouse mast cells in vitro or in vivo. Moreover, baseline levels of Fc(epsilon)RI expression on peritoneal mast cells from genetically IgE-deficient (IgE -/-) mice are dramatically reduced (by approximately 83%) compared with those on cells from the corresponding normal mice. In vitro studies indicate that the IgE-dependent upregulation of mouse mast cell Fc(epsilon)RI expression has two components: an early cycloheximide-insensitive phase, followed by a later and more sustained component that is highly sensitive to inhibition by cycloheximide. In turn, IgE-dependent upregulation of Fc(epsilon)RI expression significantly enhances the ability of mouse mast cells to release serotonin, interleukin-6 (IL-6), and IL-4 in response to challenge with IgE and specific antigen. The demonstration that IgE-dependent enhancement of mast cell Fc(epsilon)RI expression permits mast cells to respond to antigen challenge with increased production of proinflammatory and immunoregulatory mediators provides new insights into both the pathogenesis of allergic diseases and the regulation of protective host responses to parasites.

Show MeSH

Related in: MedlinePlus

IgE enhances FcεRI  expression in mouse bone marrow–derived cultured mast cells  (BMCMCs) in vitro. (A) Kinetics  of IgE-induced changes in surface FcεRI expression in BMCMCs. BMCMCs (always >95%  purity at 4–5 wk of culture) from  BALB/c (IgE +/+) mice were  cultured with or without ascites  IgE (at 5.0 μg/ml) for the indicated times. BMCMCs were  stained only for FcεRI (with  FITC–IgE) and were analyzed  by flow cytometry using a different instrument setting from that  in Fig. 1. All data are mean ±  SEM (n = 3); †† P <0.001, †††P  <0.0001 versus value at day 0.  (B) Upregulation of surface  FcεRI protein by IgE. BMCMCs from IgE −/− mice were  cultured with or without ascites  IgE at 5 μg/ml for 21 h. After  sensitization with IgE at 10 μg/ ml for 30 min at 4°C to saturate  surface FcεRI, cells (n = 2) were  analyzed by flow cytometry for  FcεRI expression (see Materials  and Methods) and by immunoprecipitation with anti-IgE and  Western blot (2.5 × 107 BMCMCs per lane) to assess levels of  surface-expressed FcεRI β chain.  The difference of detected  FcεRI expression between cells incubated with or without IgE was 14fold (by flow cytometry) and 17-fold (by Western blot), respectively.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2196143&req=5

Figure 2: IgE enhances FcεRI expression in mouse bone marrow–derived cultured mast cells (BMCMCs) in vitro. (A) Kinetics of IgE-induced changes in surface FcεRI expression in BMCMCs. BMCMCs (always >95% purity at 4–5 wk of culture) from BALB/c (IgE +/+) mice were cultured with or without ascites IgE (at 5.0 μg/ml) for the indicated times. BMCMCs were stained only for FcεRI (with FITC–IgE) and were analyzed by flow cytometry using a different instrument setting from that in Fig. 1. All data are mean ± SEM (n = 3); †† P <0.001, †††P <0.0001 versus value at day 0. (B) Upregulation of surface FcεRI protein by IgE. BMCMCs from IgE −/− mice were cultured with or without ascites IgE at 5 μg/ml for 21 h. After sensitization with IgE at 10 μg/ ml for 30 min at 4°C to saturate surface FcεRI, cells (n = 2) were analyzed by flow cytometry for FcεRI expression (see Materials and Methods) and by immunoprecipitation with anti-IgE and Western blot (2.5 × 107 BMCMCs per lane) to assess levels of surface-expressed FcεRI β chain. The difference of detected FcεRI expression between cells incubated with or without IgE was 14fold (by flow cytometry) and 17-fold (by Western blot), respectively.

Mentions: Unfractionated peritoneal cells contain cells other than mast cells, some of which may have influenced the effect of IgE on peritoneal mast cell FcεRI expression. Therefore, we next assessed whether IgE also enhanced surface expression of FcεRI in essentially pure populations of immature mouse mast cells derived in vitro from the bone marrow cells of IgE mice (IgE −/− mice) or the corresponding normal (IgE +/+) BALB/c mice (24). Incubation with IgE (at 5 μg/ml) resulted in a marked elevation (32-fold at day 4) in FcεRI expression in BMCMCs from IgE +/+ mice (Fig. 2 A). Essentially identical results were obtained in two additional experiments with BMCMCs derived from IgE −/− mice (data not shown), cell preparations which could not have contained any source of endogenous mouse IgE (i.e., small numbers of contaminating B cells).


IgE enhances mouse mast cell Fc(epsilon)RI expression in vitro and in vivo: evidence for a novel amplification mechanism in IgE-dependent reactions.

Yamaguchi M, Lantz CS, Oettgen HC, Katona IM, Fleming T, Miyajima I, Kinet JP, Galli SJ - J. Exp. Med. (1997)

IgE enhances FcεRI  expression in mouse bone marrow–derived cultured mast cells  (BMCMCs) in vitro. (A) Kinetics  of IgE-induced changes in surface FcεRI expression in BMCMCs. BMCMCs (always >95%  purity at 4–5 wk of culture) from  BALB/c (IgE +/+) mice were  cultured with or without ascites  IgE (at 5.0 μg/ml) for the indicated times. BMCMCs were  stained only for FcεRI (with  FITC–IgE) and were analyzed  by flow cytometry using a different instrument setting from that  in Fig. 1. All data are mean ±  SEM (n = 3); †† P <0.001, †††P  <0.0001 versus value at day 0.  (B) Upregulation of surface  FcεRI protein by IgE. BMCMCs from IgE −/− mice were  cultured with or without ascites  IgE at 5 μg/ml for 21 h. After  sensitization with IgE at 10 μg/ ml for 30 min at 4°C to saturate  surface FcεRI, cells (n = 2) were  analyzed by flow cytometry for  FcεRI expression (see Materials  and Methods) and by immunoprecipitation with anti-IgE and  Western blot (2.5 × 107 BMCMCs per lane) to assess levels of  surface-expressed FcεRI β chain.  The difference of detected  FcεRI expression between cells incubated with or without IgE was 14fold (by flow cytometry) and 17-fold (by Western blot), respectively.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2196143&req=5

Figure 2: IgE enhances FcεRI expression in mouse bone marrow–derived cultured mast cells (BMCMCs) in vitro. (A) Kinetics of IgE-induced changes in surface FcεRI expression in BMCMCs. BMCMCs (always >95% purity at 4–5 wk of culture) from BALB/c (IgE +/+) mice were cultured with or without ascites IgE (at 5.0 μg/ml) for the indicated times. BMCMCs were stained only for FcεRI (with FITC–IgE) and were analyzed by flow cytometry using a different instrument setting from that in Fig. 1. All data are mean ± SEM (n = 3); †† P <0.001, †††P <0.0001 versus value at day 0. (B) Upregulation of surface FcεRI protein by IgE. BMCMCs from IgE −/− mice were cultured with or without ascites IgE at 5 μg/ml for 21 h. After sensitization with IgE at 10 μg/ ml for 30 min at 4°C to saturate surface FcεRI, cells (n = 2) were analyzed by flow cytometry for FcεRI expression (see Materials and Methods) and by immunoprecipitation with anti-IgE and Western blot (2.5 × 107 BMCMCs per lane) to assess levels of surface-expressed FcεRI β chain. The difference of detected FcεRI expression between cells incubated with or without IgE was 14fold (by flow cytometry) and 17-fold (by Western blot), respectively.
Mentions: Unfractionated peritoneal cells contain cells other than mast cells, some of which may have influenced the effect of IgE on peritoneal mast cell FcεRI expression. Therefore, we next assessed whether IgE also enhanced surface expression of FcεRI in essentially pure populations of immature mouse mast cells derived in vitro from the bone marrow cells of IgE mice (IgE −/− mice) or the corresponding normal (IgE +/+) BALB/c mice (24). Incubation with IgE (at 5 μg/ml) resulted in a marked elevation (32-fold at day 4) in FcεRI expression in BMCMCs from IgE +/+ mice (Fig. 2 A). Essentially identical results were obtained in two additional experiments with BMCMCs derived from IgE −/− mice (data not shown), cell preparations which could not have contained any source of endogenous mouse IgE (i.e., small numbers of contaminating B cells).

Bottom Line: This IgE- and antigen-specific mast cell activation and mediator production is thought to be critical to the pathogenesis of allergic disorders, such as anaphylaxis and asthma, and also contributes to host defense against parasites.In turn, IgE-dependent upregulation of Fc(epsilon)RI expression significantly enhances the ability of mouse mast cells to release serotonin, interleukin-6 (IL-6), and IL-4 in response to challenge with IgE and specific antigen.The demonstration that IgE-dependent enhancement of mast cell Fc(epsilon)RI expression permits mast cells to respond to antigen challenge with increased production of proinflammatory and immunoregulatory mediators provides new insights into both the pathogenesis of allergic diseases and the regulation of protective host responses to parasites.

View Article: PubMed Central - PubMed

Affiliation: Department of Pathology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts 02215, USA.

ABSTRACT
The binding of immunoglobulin E (IgE) to high affinity IgE receptors (Fc(epsilon)RI) expressed on the surface of mast cells primes these cells to secrete, upon subsequent exposure to specific antigen, a panel of proinflammatory mediators, which includes cytokines that can also have immunoregulatory activities. This IgE- and antigen-specific mast cell activation and mediator production is thought to be critical to the pathogenesis of allergic disorders, such as anaphylaxis and asthma, and also contributes to host defense against parasites. We now report that exposure to IgE results in a striking (up to 32-fold) upregulation of surface expression of Fc(epsilon)RI on mouse mast cells in vitro or in vivo. Moreover, baseline levels of Fc(epsilon)RI expression on peritoneal mast cells from genetically IgE-deficient (IgE -/-) mice are dramatically reduced (by approximately 83%) compared with those on cells from the corresponding normal mice. In vitro studies indicate that the IgE-dependent upregulation of mouse mast cell Fc(epsilon)RI expression has two components: an early cycloheximide-insensitive phase, followed by a later and more sustained component that is highly sensitive to inhibition by cycloheximide. In turn, IgE-dependent upregulation of Fc(epsilon)RI expression significantly enhances the ability of mouse mast cells to release serotonin, interleukin-6 (IL-6), and IL-4 in response to challenge with IgE and specific antigen. The demonstration that IgE-dependent enhancement of mast cell Fc(epsilon)RI expression permits mast cells to respond to antigen challenge with increased production of proinflammatory and immunoregulatory mediators provides new insights into both the pathogenesis of allergic diseases and the regulation of protective host responses to parasites.

Show MeSH
Related in: MedlinePlus