The 86-kD subunit of Ku autoantigen mediates homotypic and heterotypic adhesion of multiple myeloma cells

Previous studies have shown that triggering multiple myeloma (MM) cells via CD40 induces IL-6-mediated autocrine growth as well as increased expression of cell surface adhesion molecules including CD11a, CD11b, CD11c, and CD18. In this study, we generated the 5E2 mAb which targets an antigen that is induced upon CD40 ligand (CD40L) activation of MM cells. Immunofluorescence, immunoprecipitation, and protein sequencing studies identified the target antigen of 5E2 mAb as the 86-kD subunit of the Ku autoantigen. We demonstrate that increased cell surface expression of Ku on CD40L-treated cells is due to migration of Ku from the cytoplasm to the cell surface membrane. Moreover, cell surface Ku on CD40L-treated MM cells mediates homotypic adhesion of tumor cells, as well as heterotypic adhesion of tumor cells to bone marrow stromal cells and to human fibronectin; and 5E2 mAb abrogates IL-6 secretion triggered by tumor cell adherence to bone marrow stromal cells. These data suggest that CD40L treatment induces a shift of Ku from the cytoplasm to the cell surface, and are the first to show that Ku functions as an adhesion molecule. They further suggest that cell surface Ku may play a role in both autocrine and paracrine IL-6-mediated MM cell growth and survival.

Medienart:

Artikel

Erscheinungsjahr:

1998

Erschienen:

1998

Enthalten in:

Zur Gesamtaufnahme - volume:101

Enthalten in:

The Journal of clinical investigation - 101(1998), 6 vom: 15. März, Seite 1379-88

Sprache:

Englisch

Beteiligte Personen:

Teoh, G [VerfasserIn]
Urashima, M [VerfasserIn]
Greenfield, E A [VerfasserIn]
Nguyen, K A [VerfasserIn]
Lee, J F [VerfasserIn]
Chauhan, D [VerfasserIn]
Ogata, A [VerfasserIn]
Treon, S P [VerfasserIn]
Anderson, K C [VerfasserIn]

Themen:

147205-72-9
Antibodies, Blocking
Antibodies, Monoclonal
Antigens, CD
Antigens, Nuclear
Autoantibodies
CD40 Antigens
CD40 Ligand
DNA Helicases
DNA-Binding Proteins
EC 3.6.4.-
EC 3.6.4.12
EC 4.2.99.-
Fibronectins
Interleukin-6
Journal Article
Ku Autoantigen
Membrane Glycoproteins
Nuclear Proteins
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, P.H.S.
XRCC5 protein, human
Xrcc6 protein, human
Xrcc6 protein, mouse

Anmerkungen:

Date Completed 23.04.1998

Date Revised 01.12.2018

published: Print

Citation Status MEDLINE

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM09444742X