A new concept for the separation of cells will be developed and evaluated. The basis of this separation technique, called immunoflotation, is a solid matrix that floats in water, making it possible to separate bound cells from unbound cells without centrifugation. Either antigen or antibody is coupled to the surface of the buoyant matrix. Cells bearing on their surface an antibody or antigen complementary to the ligand on the matrix are added to a suspension of the matrix. Cells that bind to the matrix float to the surface of the suspension by virtue of the buoyant properties of the matrix. The feasibility of this approach has been demonstrated, using as the buoyant matrix milk fat globules (MFG's). MFG's are tiny spheres of densely packed lipid surrounded by a plasma membrane. They are found in raw milk, making them extremely cost effective. The MFG's float in water, have glycoproteins on their surface for the covalent coupling of antigen or antibody, and when settled, form a white layer at the top of the reaction tube. It is planned to test the ability of antibody linked to MFG to separate cloned cell lines, B and T lymphocyte populations, and various subpopulations from heterogeneous cell mixtures on the basis of the presence or absence of specific antigens.
Anticipated Results:The development of a novel cell separation procedure based on the flotation of MFG's will provide an inexpensive, rapid, and sterile technique for fractionating heterogeneous cell populations. It can have applications in clinical areas relating to bone marrow replacement, allografts, and leukopheresis, as well as biomedical research on the genetics, physiology, and biochemistry of isolated subpopulations of cells.National Institute of Allergy And Infectious Diseases
