Epitope mapping of antibodies to the C-terminal region of the integrin β2 subunit reveals regions that become exposed upon receptor activation

C. Lu, M. Ferzly, J. Takagi, T. A. Springer

Research output: Contribution to journalArticle

128 Citations (Scopus)

Abstract

The cysteine-rich repeats in the stalk region of integrin β subunits appear to convey signals impinging on the cytoplasmic domains to the ligand-binding headpiece of integrins. We have examined the functional properties of mAbs to the stalk region and mapped their epitopes, providing a structure-function map. Among a panel of 14 mAbs to the β2 subunit, one, KIM127, preferentially bound to αLβ2 that was activated by mutations in the cytoplasmic domains, and by Mn2+. KIM127 also bound preferentially to the free β2 subunit compared with resting αLβ2 Activating β2 mutations also greatly enhanced binding of KIM127 to integrins αMβ2 and αXβ2. Thus, the KIM127 epitope is shielded by the α subunit, and becomes reexposed upon receptor activation. Three other mAbs, CBR LFA-1/2, MEM48, and KIM185, activated αLβ2 and bound equally well to resting and activated αLβ2, differentially recognized resting αMβ2 and αXβ2, and bound fully to activated αMβ2 andαXβ2. The KIM127 epitope localizes within cysteine-rich repeat 2, to residues 504, 506, and 508. By contrast, the two activating mAbs CBR LFA-1/2 and MEM48 bind to overlapping epitopes involving residues 534, 536, 541, 543, and 546 in cysteine-rich repeat 3, and the activating mAb KIM185 maps near the end of cysteine-rich repeat 4. The nonactivating mAbs, 6.7 and CBR LFA-1/7, map more N-terminal, to subregions 344-432 and 432-487, respectively. We thus define rive different β2 stalk subregions, mAb binding to which correlates with effect on activation, and define regions in an interface that becomes exposed upon integrin activation.

Original languageEnglish (US)
Pages (from-to)5629-5637
Number of pages9
JournalJournal of Immunology
Volume166
Issue number9
StatePublished - May 1 2001

Fingerprint

Epitope Mapping
Integrins
Lymphocyte Function-Associated Antigen-1
Cysteine
Epitopes
Antibodies
Mutation
Ligands

ASJC Scopus subject areas

  • Immunology

Cite this

Epitope mapping of antibodies to the C-terminal region of the integrin β2 subunit reveals regions that become exposed upon receptor activation. / Lu, C.; Ferzly, M.; Takagi, J.; Springer, T. A.

In: Journal of Immunology, Vol. 166, No. 9, 01.05.2001, p. 5629-5637.

Research output: Contribution to journalArticle

@article{d480ac4490184f409698b0e18a01d618,
title = "Epitope mapping of antibodies to the C-terminal region of the integrin β2 subunit reveals regions that become exposed upon receptor activation",
abstract = "The cysteine-rich repeats in the stalk region of integrin β subunits appear to convey signals impinging on the cytoplasmic domains to the ligand-binding headpiece of integrins. We have examined the functional properties of mAbs to the stalk region and mapped their epitopes, providing a structure-function map. Among a panel of 14 mAbs to the β2 subunit, one, KIM127, preferentially bound to αLβ2 that was activated by mutations in the cytoplasmic domains, and by Mn2+. KIM127 also bound preferentially to the free β2 subunit compared with resting αLβ2 Activating β2 mutations also greatly enhanced binding of KIM127 to integrins αMβ2 and αXβ2. Thus, the KIM127 epitope is shielded by the α subunit, and becomes reexposed upon receptor activation. Three other mAbs, CBR LFA-1/2, MEM48, and KIM185, activated αLβ2 and bound equally well to resting and activated αLβ2, differentially recognized resting αMβ2 and αXβ2, and bound fully to activated αMβ2 andαXβ2. The KIM127 epitope localizes within cysteine-rich repeat 2, to residues 504, 506, and 508. By contrast, the two activating mAbs CBR LFA-1/2 and MEM48 bind to overlapping epitopes involving residues 534, 536, 541, 543, and 546 in cysteine-rich repeat 3, and the activating mAb KIM185 maps near the end of cysteine-rich repeat 4. The nonactivating mAbs, 6.7 and CBR LFA-1/7, map more N-terminal, to subregions 344-432 and 432-487, respectively. We thus define rive different β2 stalk subregions, mAb binding to which correlates with effect on activation, and define regions in an interface that becomes exposed upon integrin activation.",
author = "C. Lu and M. Ferzly and J. Takagi and Springer, {T. A.}",
year = "2001",
month = "5",
day = "1",
language = "English (US)",
volume = "166",
pages = "5629--5637",
journal = "Journal of Immunology",
issn = "0022-1767",
publisher = "American Association of Immunologists",
number = "9",

}

TY - JOUR

T1 - Epitope mapping of antibodies to the C-terminal region of the integrin β2 subunit reveals regions that become exposed upon receptor activation

AU - Lu, C.

AU - Ferzly, M.

AU - Takagi, J.

AU - Springer, T. A.

PY - 2001/5/1

Y1 - 2001/5/1

N2 - The cysteine-rich repeats in the stalk region of integrin β subunits appear to convey signals impinging on the cytoplasmic domains to the ligand-binding headpiece of integrins. We have examined the functional properties of mAbs to the stalk region and mapped their epitopes, providing a structure-function map. Among a panel of 14 mAbs to the β2 subunit, one, KIM127, preferentially bound to αLβ2 that was activated by mutations in the cytoplasmic domains, and by Mn2+. KIM127 also bound preferentially to the free β2 subunit compared with resting αLβ2 Activating β2 mutations also greatly enhanced binding of KIM127 to integrins αMβ2 and αXβ2. Thus, the KIM127 epitope is shielded by the α subunit, and becomes reexposed upon receptor activation. Three other mAbs, CBR LFA-1/2, MEM48, and KIM185, activated αLβ2 and bound equally well to resting and activated αLβ2, differentially recognized resting αMβ2 and αXβ2, and bound fully to activated αMβ2 andαXβ2. The KIM127 epitope localizes within cysteine-rich repeat 2, to residues 504, 506, and 508. By contrast, the two activating mAbs CBR LFA-1/2 and MEM48 bind to overlapping epitopes involving residues 534, 536, 541, 543, and 546 in cysteine-rich repeat 3, and the activating mAb KIM185 maps near the end of cysteine-rich repeat 4. The nonactivating mAbs, 6.7 and CBR LFA-1/7, map more N-terminal, to subregions 344-432 and 432-487, respectively. We thus define rive different β2 stalk subregions, mAb binding to which correlates with effect on activation, and define regions in an interface that becomes exposed upon integrin activation.

AB - The cysteine-rich repeats in the stalk region of integrin β subunits appear to convey signals impinging on the cytoplasmic domains to the ligand-binding headpiece of integrins. We have examined the functional properties of mAbs to the stalk region and mapped their epitopes, providing a structure-function map. Among a panel of 14 mAbs to the β2 subunit, one, KIM127, preferentially bound to αLβ2 that was activated by mutations in the cytoplasmic domains, and by Mn2+. KIM127 also bound preferentially to the free β2 subunit compared with resting αLβ2 Activating β2 mutations also greatly enhanced binding of KIM127 to integrins αMβ2 and αXβ2. Thus, the KIM127 epitope is shielded by the α subunit, and becomes reexposed upon receptor activation. Three other mAbs, CBR LFA-1/2, MEM48, and KIM185, activated αLβ2 and bound equally well to resting and activated αLβ2, differentially recognized resting αMβ2 and αXβ2, and bound fully to activated αMβ2 andαXβ2. The KIM127 epitope localizes within cysteine-rich repeat 2, to residues 504, 506, and 508. By contrast, the two activating mAbs CBR LFA-1/2 and MEM48 bind to overlapping epitopes involving residues 534, 536, 541, 543, and 546 in cysteine-rich repeat 3, and the activating mAb KIM185 maps near the end of cysteine-rich repeat 4. The nonactivating mAbs, 6.7 and CBR LFA-1/7, map more N-terminal, to subregions 344-432 and 432-487, respectively. We thus define rive different β2 stalk subregions, mAb binding to which correlates with effect on activation, and define regions in an interface that becomes exposed upon integrin activation.

UR - http://www.scopus.com/inward/record.url?scp=0035341132&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0035341132&partnerID=8YFLogxK

M3 - Article

C2 - 11313403

AN - SCOPUS:0035341132

VL - 166

SP - 5629

EP - 5637

JO - Journal of Immunology

JF - Journal of Immunology

SN - 0022-1767

IS - 9

ER -