Detection of soluble CR3 (CD11b/CD18) by time-resolved immunofluorometry.
In the cell membrane complement receptor 3 (CR3) consists of one alpha chain (CD11b) and one beta chain (CD18). CR3 participates in many immunological processes, especially those involving cell migration, adhesion, and phagocytosis of complement-opsonized microbes. Recent findings of soluble CR3 in body fluids and in culture supernatant from experiments in vitro point to the involvement of ecto domain shedding as a part of the CR3 biology. To monitor such shedding on a quantitative basis, we have developed time-resolved immunofluorometric assays (TRIFMA) to detect soluble CD11b and CD18 in plasma or serum of either human or murine origin. Compared with most enzyme-linked immunosorbent assays methodologies, TRIFMA possesses prominent advantages, including better dynamic range and reproducibility. These assays may contribute to the understanding of the role of shedding of CR3 and other cell adhesion molecules in human disease and animal models involving inflammation.
Biophysical Immunology Laboratory, Department of Biomedicine, The Lundbeck Foundation Nanomedicine Center for Individual Management of Tissue Damage and Regeneration, Aarhus University, Aarhus, Denmark.
Gitte Krogh
GK
Nielsen
Thomas
T
Vorup-Jensen
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D039481:CD11b Antigen / Q000276:immunology / Q000378:metabolism; D018821:CD18 Antigens / Q000276:immunology / Q000378:metabolism; D015200:Fluoroimmunoassay / Q000379:methods*; D006801:Humans; D016177:Macrophage-1 Antigen / Q000276:immunology / Q000378:metabolism*; D051379:Mice
D000911:Antibodies, Monoclonal; D039481:CD11b Antigen; D018821:CD18 Antigens; D016177:Macrophage-1 Antigen