Actin-binding protein filamin A is displayed on the surface of human neuroblastoma cells.
We previously reported the identification of natural human IgM antibodies, which recognize a M(r) 260 000 surface protein (NB-p260) and induce both complement-mediated cytotoxicity and apoptosis of human neuroblastoma cells. NB-p260 was shown to belong to the family of filamin proteins. Filamin A is a high molecular weight actin-binding protein, previously thought to be only located intracellularly. Here we show that NB cells as well as three NB-unrelated human cell lines express filamin A also on the cell surface. Our findings suggest new biological functions for filamins, including a role as mediators in anti-NB IgM-induced apoptosis, and they add to the growing body of evidence of the interaction of cytoskeletal proteins with the extracellular matrix.
Bachmann
André S
AS
Cancer Research Center of Hawaii, University of Hawaii at Manoa, 1236 Lauhala Street, Honolulu, Hawaii 96813, USA.
Howard
James P
JP
Vogel
Carl-Wilhelm
CW
D000199:Actins / Q000276:immunology / Q000378:metabolism*; D019921:Biotinylation; D015153:Blotting, Western; D002462:Cell Membrane / Q000378:metabolism*; D002478:Cells, Cultured; D003285:Contractile Proteins / Q000276:immunology / Q000378:metabolism*; D003599:Cytoskeleton / Q000276:immunology / Q000378:metabolism*; D005260:Female; D064448:Filamins; D005434:Flow Cytometry; D006801:Humans; D007124:Immunoenzyme Techniques; D007668:Kidney / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D008545:Melanoma / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D008840:Microfilament Proteins / Q000276:immunology / Q000378:metabolism*; D009447:Neuroblastoma / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D010051:Ovarian Neoplasms / Q000276:immunology / Q000378:metabolism / Q000473:pathology
D000199:Actins; D003285:Contractile Proteins; D064448:Filamins; D008840:Microfilament Proteins