IgM binding protein expressed by activated B cells.

Abstract

We have identified an IgM binding protein, a single chain polypeptide of Mr 60,000, that is expressed on the surface of B lymphocytes within 18 hr following their activation with phorbol myristate acetate. The IgM binding protein was also detected on fresh leukemic B cells from individuals with chronic lymphocytic leukemia, and the level of its expression was increased after phorbol myristate acetate activation. Resting and phorbol myristate acetate-activated T cells, monocytes, and polymorphonuclear leucocytes did not express detectable amounts of the IgM binding protein. The 60-kDa protein on activated human B cells could bind secreted IgM molecules of both mouse and human origin, as well as endogenous membrane-bound IgM molecules following their cross-linkage with anti-mu antibodies. The binding of soluble IgM molecules to the surface of activated B cells was also demonstrated by indirect immunofluorescence analysis.

• Authors: S K Sanders, H Kubagawa, T Suzuki, J L Butler, M D Cooper
• Journal: Journal of immunology (Baltimore, Md. : 1950) (J Immunol) Vol. 139 Issue 1 Pg. 188-93 (Jul 01 1987) ISSN: 0022-1767 [Print] United States
• PMID: 3495598 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Immunoglobulin M
• Lymphokines
• Prostatic Secretory Proteins
• beta-microseminoprotein
• immunoglobulin-binding factors

Topics

• B-Lymphocytes (immunology)
• Cell Line
• Cell Membrane (metabolism)
• Humans
• Immunoglobulin M (metabolism)
• Lymphocyte Activation
• Lymphokines (metabolism)
• Macrophages (metabolism)
• Molecular Weight
• Prostatic Secretory Proteins
• T-Lymphocytes (metabolism)