Frozen section microautoradiography in the study of radionuclide targeting: Application to indium-111-oxine-labeled leukocytes

Journal Article · Wed Mar 01 00:00:00 EST 1995 · Journal of Nuclear Medicine

OSTI ID:508543

Puncher, M R.B.; Blower, P J ^[1]

---

1. Univ. of Canterbury (United Kingdom)

The microscopic biodistribution of radioactivity in tissues is important in determining microdosimetry. This study addresses the use of frozen section microautoradiography in studying the subcellular distribution of {sup 111}In in leukocytes labeled with {sup 111}In-oxine. In conjunction with frozen section microautoradiography, computer image analysis methods were applied to the analysis and quantification of leukocyte sections and superimposed autoradiographs. Rapid cell fractionation was used to confirm the results. The emulsion (Ilford K2) response was linear over the concentration range investigated (0-33 MBq ml{sup 1}). Resolution of radionuclide distribution was better than 2 {mu}m. The autoradiographs showed no dependence of radiolabel uptake on cell type. Classification of all cells into intervals according to grain density suggests an exponential rather than normal distribution, with approximately 50% of cells having little or no radiolabel. In any one sample, cells which were heavily labeled were approximately 10 times more likely to be found in aggregates (60% found in aggregates, mostly neutrophils) than cells which were not heavily labeled (6% found in aggregates); and the grain densities were at least twofold higher over nuclei than over cytoplasm. The last observation was confirmed by the rapid cell fractionation method which showed that approximately 57% of the total radioactivity was bound to nuclei. Frozen section microautoradiography is a practical and reliable approach to determining sub-cellular distribution of {sup 111}In. The radiolabeling process causes aggregation of neutrophils. Uptake is not significantly dependent on cell type, but only a fraction of cells are appreciably labeled. The radioactive concentration in cell nuclei is at least two-fold higher than in cytoplasm. Microautoradiography can be used to provide distribution data as input into computer models for sub-cellular dosimetry. 24 refs., 5 figs., 1 tab.

• OSTI ID: 508543
• Journal Information: Journal of Nuclear Medicine, Vol. 36, Issue 3; Other Information: PBD: Mar 1995
• Country of Publication: United States
• Language: English

Related Subjects

56 BIOLOGY AND MEDICINE
APPLIED STUDIES
55 BIOLOGY AND MEDICINE
BASIC STUDIES
INDIUM 111
UPTAKE
LEUKOCYTES
BIOLOGICAL RADIATION EFFECTS
RADIOSENSITIVITY
MICRODOSIMETRY
MATHEMATICAL MODELS
RADIOACTIVITY
TISSUE DISTRIBUTION
NEUTROPHILS
AGGLOMERATION
RADIOPHARMACEUTICALS
THERAPEUTIC USES
RETENTION
RADIONUCLIDE KINETICS
RADIOISOTOPES
OXINE
IMAGES
AUTORADIOGRAPHY
CELL NUCLEI
GRAIN DENSITY
CYTOPLASM
DIAGNOSTIC TECHNIQUES
EMULSIONS