Distribution of [sup 65]Zn labeled alpha-fetoprotein during proliferation of the BW7756 murine hepatoma
The radiolabeling of alpha-fetoprotein (AFP) with [sup 65]Zn for the determination of its biodistribution was studied in mice bearing the BW7756 murine hepatoma as compared to that found with normal mice. AFP is an oncofetal protein of about 70,000 daltons associated with pregnancy and certain cancers (e.g., hepatoma). The AFP was purified from mouse amniotic fluid (MAF) using polyacrylamide gel electrophoresis (PAGE) and higher performance liquid chromatography (HPLC). The biological activity of AFP was maintained through the separation procedures and the purity was determined using double immunodiffusion (DID), immunoelectrophoresis (IEP) and sodium dodecyl sulfate electrophoresis (SDS). The labeling procedures included removal of intrinsic metal with EDTA, incubation with radiotracer ([sup 65]Zn) and buffer, followed by removal of unbound [sup 65]Zn using gel filtration chromatography. The results correlated well with Zn fluctuations recorded by other techniques (RIXRF, radiotracer [sup 65]Zn). Large amounts of [sup 65]Zn-AFP were localized in the liver, spleen and tumor with significant elevations above normal in the log growth phase (day 14-18). [sup 65]Zn-AFP levels in the skin, pancreas, brain and thyroid decreased as the tumor mass increased. Tumor [sup 65]Zn-AFP uptake increased with time but leveled off in the late log phase (day 21) due to tumor necrosis. In light of the results of this investigation, and previous work stating that AFP binds Zn with a higher affinity than does albumin, it is suggestive that the Zn fluctuations observed in the earlier hepatoma studies were due to the in vivo binding of Zn to AFP. These results confirm the thesis that intrinsic labeling (replacement of naturally bound ligands with radioactive analogs) does not alter the biochemical integrity as non-intrinsic labeling (e.g., Iodine) may.
- Research Organization:
- Rensselaer Polytechnic Inst., Troy, NY (United States)
- OSTI ID:
- 7013969
- Resource Relation:
- Other Information: Thesis (Ph.D.)
- Country of Publication:
- United States
- Language:
- English
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HEPATOMAS
CELL PROLIFERATION
ZINC COMPOUNDS
EXPERIMENTAL DATA
LABELLED COMPOUNDS
LABELLING
MICE
SCINTILLATION COUNTING
TRACER TECHNIQUES
TUMOR CELLS
ZINC 65
ANIMAL CELLS
ANIMALS
ANTIGENS
BETA DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
CARCINOMAS
COUNTING TECHNIQUES
DATA
DAYS LIVING RADIOISOTOPES
DISEASES
DISTRIBUTION
ELECTRON CAPTURE RADIOISOTOPES
EVEN-ODD NUCLEI
INFORMATION
INTERMEDIATE MASS NUCLEI
ISOTOPE APPLICATIONS
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MAMMALS
NEOPLASMS
NUCLEI
NUMERICAL DATA
RADIOISOTOPES
RODENTS
VERTEBRATES
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550601* - Medicine- Unsealed Radionuclides in Diagnostics