Cleavage of human IgE mediated by Schistosoma mansoni

Richard J. Pleass, John R. Kusel, Jenny M. Woof (Lead / Corresponding author)

Research output: Contribution to journalArticle

27 Citations (Scopus)

Abstract

Background: IgE-mediated mechanisms are important in protection against helminth parasites. However, schistosomes are long-lived in mammalian hosts, presumably as a result of immune evasion strategies. We sought evidence for one such strategy, namely specific cleavage of host IgE.

Methods: Human IgE, IgA and IgG were incubated with extracts from cercarial and schistosomular stages of Schistosoma mansoni or with schistosomular culture supernatants. The resulting products were analysed by Western blotting with Ig-specific antibodies. Numerous protease inhibitors were assessed for ability to inhibit the observed cleavage of IgE by the extracts. Partial purification of the IgE-proteolytic activity from cercarial extract was achieved by gel filtration. To test IgE function, we compared the abilities of untreated and schistosomular-treated IgE to mediate rosette formation through interaction with Fcε receptors.

Results: Cercarial and schistosomular extracts were found to cleave human, mouse and rat IgE but not human IgA1, IgA2 or IgG1. Schistosomular culture supernatants displayed similar proteolytic activity towards IgE. Immunoblotting suggested that cleavage occurred close to the Cε2/Cε3 domain interface of the IgE heavy chain. PMSF and elastatinal inhibited cleavage, suggesting that the protease involved is an elastase-like serine protease, particularly since porcine pancreatic elastase also cleaved IgE to give similar-sized products. Further, the chloromethyl ketone derivatized peptide MeO-Suc-Ala-Ala-Pro-Leu-CMK, known to specifically inhibit the schistosome elastase, prevented IgE cleavage. Cleavage of human IgE rendered the antibody molecule unable to interact with U937 cells expressing FcεRII.

Conclusions: An elastase-like protease in S. mansoni is able to render IgE nonfunctional.

Original languageEnglish
Pages (from-to)194-204
Number of pages11
JournalInternational Archives of Allergy and Immunology
Volume121
Issue number3
DOIs
Publication statusPublished - Mar 2000

Fingerprint

Schistosoma mansoni
Immunoglobulin E
Pancreatic Elastase
Immunoglobulin A
Amino Acid Chloromethyl Ketones
Immunoglobulin G
Immune Evasion
Rosette Formation
U937 Cells
Fc Receptors
Antibodies
Helminths
Serine Proteases
Protease Inhibitors
Immunoblotting
Gel Chromatography

Keywords

  • Elastase
  • IgE
  • Immune evasion
  • Protease
  • Schistosoma mansoni

Cite this

Pleass, Richard J. ; Kusel, John R. ; Woof, Jenny M. / Cleavage of human IgE mediated by Schistosoma mansoni. In: International Archives of Allergy and Immunology. 2000 ; Vol. 121, No. 3. pp. 194-204.
@article{8f75af72cd8542e790e3f5bb89a45019,
title = "Cleavage of human IgE mediated by Schistosoma mansoni",
abstract = "Background: IgE-mediated mechanisms are important in protection against helminth parasites. However, schistosomes are long-lived in mammalian hosts, presumably as a result of immune evasion strategies. We sought evidence for one such strategy, namely specific cleavage of host IgE.Methods: Human IgE, IgA and IgG were incubated with extracts from cercarial and schistosomular stages of Schistosoma mansoni or with schistosomular culture supernatants. The resulting products were analysed by Western blotting with Ig-specific antibodies. Numerous protease inhibitors were assessed for ability to inhibit the observed cleavage of IgE by the extracts. Partial purification of the IgE-proteolytic activity from cercarial extract was achieved by gel filtration. To test IgE function, we compared the abilities of untreated and schistosomular-treated IgE to mediate rosette formation through interaction with Fcε receptors.Results: Cercarial and schistosomular extracts were found to cleave human, mouse and rat IgE but not human IgA1, IgA2 or IgG1. Schistosomular culture supernatants displayed similar proteolytic activity towards IgE. Immunoblotting suggested that cleavage occurred close to the Cε2/Cε3 domain interface of the IgE heavy chain. PMSF and elastatinal inhibited cleavage, suggesting that the protease involved is an elastase-like serine protease, particularly since porcine pancreatic elastase also cleaved IgE to give similar-sized products. Further, the chloromethyl ketone derivatized peptide MeO-Suc-Ala-Ala-Pro-Leu-CMK, known to specifically inhibit the schistosome elastase, prevented IgE cleavage. Cleavage of human IgE rendered the antibody molecule unable to interact with U937 cells expressing FcεRII.Conclusions: An elastase-like protease in S. mansoni is able to render IgE nonfunctional.",
keywords = "Elastase, IgE, Immune evasion, Protease, Schistosoma mansoni",
author = "Pleass, {Richard J.} and Kusel, {John R.} and Woof, {Jenny M.}",
year = "2000",
month = "3",
doi = "10.1159/000024317",
language = "English",
volume = "121",
pages = "194--204",
journal = "International Archives of Allergy and Immunology",
issn = "1018-2438",
publisher = "Karger",
number = "3",

}

Cleavage of human IgE mediated by Schistosoma mansoni. / Pleass, Richard J.; Kusel, John R.; Woof, Jenny M. (Lead / Corresponding author).

In: International Archives of Allergy and Immunology, Vol. 121, No. 3, 03.2000, p. 194-204.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Cleavage of human IgE mediated by Schistosoma mansoni

AU - Pleass, Richard J.

AU - Kusel, John R.

AU - Woof, Jenny M.

PY - 2000/3

Y1 - 2000/3

N2 - Background: IgE-mediated mechanisms are important in protection against helminth parasites. However, schistosomes are long-lived in mammalian hosts, presumably as a result of immune evasion strategies. We sought evidence for one such strategy, namely specific cleavage of host IgE.Methods: Human IgE, IgA and IgG were incubated with extracts from cercarial and schistosomular stages of Schistosoma mansoni or with schistosomular culture supernatants. The resulting products were analysed by Western blotting with Ig-specific antibodies. Numerous protease inhibitors were assessed for ability to inhibit the observed cleavage of IgE by the extracts. Partial purification of the IgE-proteolytic activity from cercarial extract was achieved by gel filtration. To test IgE function, we compared the abilities of untreated and schistosomular-treated IgE to mediate rosette formation through interaction with Fcε receptors.Results: Cercarial and schistosomular extracts were found to cleave human, mouse and rat IgE but not human IgA1, IgA2 or IgG1. Schistosomular culture supernatants displayed similar proteolytic activity towards IgE. Immunoblotting suggested that cleavage occurred close to the Cε2/Cε3 domain interface of the IgE heavy chain. PMSF and elastatinal inhibited cleavage, suggesting that the protease involved is an elastase-like serine protease, particularly since porcine pancreatic elastase also cleaved IgE to give similar-sized products. Further, the chloromethyl ketone derivatized peptide MeO-Suc-Ala-Ala-Pro-Leu-CMK, known to specifically inhibit the schistosome elastase, prevented IgE cleavage. Cleavage of human IgE rendered the antibody molecule unable to interact with U937 cells expressing FcεRII.Conclusions: An elastase-like protease in S. mansoni is able to render IgE nonfunctional.

AB - Background: IgE-mediated mechanisms are important in protection against helminth parasites. However, schistosomes are long-lived in mammalian hosts, presumably as a result of immune evasion strategies. We sought evidence for one such strategy, namely specific cleavage of host IgE.Methods: Human IgE, IgA and IgG were incubated with extracts from cercarial and schistosomular stages of Schistosoma mansoni or with schistosomular culture supernatants. The resulting products were analysed by Western blotting with Ig-specific antibodies. Numerous protease inhibitors were assessed for ability to inhibit the observed cleavage of IgE by the extracts. Partial purification of the IgE-proteolytic activity from cercarial extract was achieved by gel filtration. To test IgE function, we compared the abilities of untreated and schistosomular-treated IgE to mediate rosette formation through interaction with Fcε receptors.Results: Cercarial and schistosomular extracts were found to cleave human, mouse and rat IgE but not human IgA1, IgA2 or IgG1. Schistosomular culture supernatants displayed similar proteolytic activity towards IgE. Immunoblotting suggested that cleavage occurred close to the Cε2/Cε3 domain interface of the IgE heavy chain. PMSF and elastatinal inhibited cleavage, suggesting that the protease involved is an elastase-like serine protease, particularly since porcine pancreatic elastase also cleaved IgE to give similar-sized products. Further, the chloromethyl ketone derivatized peptide MeO-Suc-Ala-Ala-Pro-Leu-CMK, known to specifically inhibit the schistosome elastase, prevented IgE cleavage. Cleavage of human IgE rendered the antibody molecule unable to interact with U937 cells expressing FcεRII.Conclusions: An elastase-like protease in S. mansoni is able to render IgE nonfunctional.

KW - Elastase

KW - IgE

KW - Immune evasion

KW - Protease

KW - Schistosoma mansoni

UR - http://www.scopus.com/inward/record.url?scp=0034098248&partnerID=8YFLogxK

U2 - 10.1159/000024317

DO - 10.1159/000024317

M3 - Article

C2 - 10729777

AN - SCOPUS:0034098248

VL - 121

SP - 194

EP - 204

JO - International Archives of Allergy and Immunology

JF - International Archives of Allergy and Immunology

SN - 1018-2438

IS - 3

ER -