Leucocytes labelled

The safe and accurate diagnosis of diseases by using radiopharmaceuticals represents an important contribution of atomic energy to human health. Mercury, as Hg (half-life 64 h), is much used for kidney screening as it is selectively concentrated in the renal tubules. Leucocytes labelled with... 

Unquenched endogenous alkaline phosphatase activity may be seen in leucocytes, kidney, liver, bone, ovary bladder, salivary glands, placenta and gastro-intestinal tissue. Add levamisole to the alkaline phosphatase chromogen reagent or use another enzyme label such as horseradish peroxidase. Intestinal alkaline phosphatase is not quenched by the addition of levamisole. Pretreat the tissue with 0.03 N HCI. 115-121... 

The method of biosynthetic incorporation of spin label, rather than mechanical addition to isolated material, is a convenient way of ensuring that the results obtained are biologically meaningful and has also been used with such systems as the mould Neurospora crassa [158], Mycoplasma laidlawii [159], human leucocytes, and mouse L cells [160]. The spectra from these two mammalian cells showed distinct similarities for a variety of spin labels, but different spectra were obtained when the labels were incorporated in human erythrocytes. Fractionation of the cell components showed the stearic acid (C, n = 3) spin label in all the major fractions, but by far the largest concentration was in the nuclear membrane. The ESR spectrum underwent a time and temperature dependent decay and spin labels on the surface membrane were reactivated with K3Fe(CN)6. 

Segal AW, Thakur ML, Amot RN, et al. Indium-Ill-labelled leucocytes for localization of abscesses. Lancet 1976 2 1056-1058. 

Wni i c phagocytic labeling of leucocytes proceeded for instance with a commercial suinTc-albumin colloid kit. ITie leucocytes were separated from 40 ml heparinized blood. ITie preparation appeared to be stable for 2-3 h after labeling. Imaging time was 30 min to 4 h post-administration. About 20 % of the labeled colloid remained unbound to the WBCs. The preparation contained approximately equal activities of granulocytes and monocytes [163. ... 

Bioaffinity chromatography is also a useful tool for the solution of the mechanism of enzymatic processes [140]. Akanuma et al. [141] employed this method for the study of the binding site of bovine carboxypeptidase B on the basis of a complex formation with immobilized substrate analogues of basic and aromatic amino acids. The problem of determining peptides of the active sites of enzymes or antibodies can be solved by the isolation of labelled specific peptides as is shown in section 4.7.5.7. Bioaffinity chromatography was also applied to the study of the molecular structures of human fibroblast and leucocyte interpherones [142]. 

McAeee JG and Thakur ML (1976) Survey of radioactive agents for the in vitro labelling of phagocytic leucocytes. I. Soluble agents. II. Particles. J Nucl Med 17 480-492. 

In-labeled white blood cells (WBC) have also been clinically used for infection and inflammation imaging. The neutral, lipid-soluble "In(oxine)3 (oxine = 8-hydroxyquinoline) complex penetrates cellular membranes and is used to label WBC. After diffusing intracellularly, the "In(oxine)3 complex dissociates and the " In is bound to nuclear and cytoplasmic proteins. Labeling of WBCs is done in plasma to avoid transchelation with transferrin in blood. The procedure consists of withdrawal of blood from patient, separation of red blood cells from white blood cells, purification of leucocytes, radiolabeling, followed by reinjection of the radiolabeled cells into the patient. The WBCs migrate to inflamed area and can lead to positive imaging. 

A 2 ml aliquot of the leucocyte suspension was then added to a test-tube (1.5 X 11 cm.), pre-loaded with the glycine substrate (1 ml containing 2 xC of uniformly labelled glycine- C and 6.6 mgm... 

Figure 5.5 Electron Micrographs of Staphylococcus aureus M Showing the Disposition of C3 Fixed on the Bacterial Surface. S. aureus incubated in normal serum, and then treated with peroxidase labelled anti-C3 (A), or buffer as control (B). C3 is visible as a densely staining region at the cell wall (arrow), beneath the external surface. When immune antibody is present in the serum (C), the C3 is deposited throughout the capsular layer including the true external surface where it is accessible to leucocyte receptors. Reproduced by permission, Verbrugh H.A., Peterson P.K., Nguyen B.T., Sisson S.P. and Kim Y., J. Immunology 129,...

Anti-(5. mutans) serum antibodies (IgG, IgM) and sensitized lymphocytes have been found in the peripheral blood of humans and it is now known from radioactive-labelling experiments that these molecules can pass via the gingival crevice into the oral fluids. To date, IgG, IgA and IgM, phagocytic monocytes, polymorphonuclear leucocytes, macrophages, complement (C3), blast cells and T- and B-lymphocytes have all been detected in crevicular fluid so that the immimoprotective components necessary for bacterial opsonization and phagocytosis are concentrated into this area. 

Wadenvik H, Kutti J, Lindholm A. Leucocyte removal filtration of platelet concentrates. A study of platelet loss using In-labelled platelets and dynamic gamma camera scintigraphy. Eur J Haematol 1991 47 192-6. 

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