Biokinetics of a radioiodinated antibreast carcinoma monoclonal antibody and fragment in humans

Conference · Sun Jan 01 04:00:00 EST 1984 · J. Nucl. Med.; (United States)

OSTI ID:6593470

Zalutsky, M R; Noska, M; Kaplan, W D; Hayes, D; Colcher, D; Schlom, J; Kufe, D

Monoclonal antibody B6.2 is promising for the detection of breast cancers; it binds to >80% of human breast carcinoma (hbc) lines, its antigen is not seen in serum, and it localizes selectively in hbc xenografts in nude mice. The authors have studied the biokinetics of I-131 activity following injection of I-131-IgG and F(ab')/sub 2/ each in 4 patients (pts). The antibody was labeled using iodogen and tested for specific binding to hbc membrane extracts prior to injection. Pts received 0.6-1.1 mCi of I-131 and 50-100 ..mu..g of protein. Blood clearance of I-131 activity was biphasic with half times of 2 and 15.4 hrs for IgG; 1 and 30 hrs for F(ab')/sub 2/. Dehalogenation was noted: by 72 hrs post-injection, 22% (IgG) and 21% (F(ab')/sub 2/) of the injected dose of I-131 was found in the urine. In 2 pts receiving I-131 IgG, stomach uptake was 7-10% at 24 hrs. Protein associated activity in the blood was >90% for the first 8 hrs and gradually decreased to 79% (IgG) and 58% (F(ab')/sub 2/) at 48 hrs. High liver uptake, reported with other antibody systems, was not observed; <20% of the activity was seen in the liver at all time points for both proteins. In 1/4 pts receiving IgG and 4/4 receiving F(ab')/sub 2/, bone marrow uptake was clearly noted. In these pts, >20% of the activity present in blood was cell associated. This is not inconsistent with the observation that B6.2 binds to granulocytes in vitro. Increased binding to cells in the blood for F(ab')/sub 2/ probably accounts for the anomolously longer blood clearance half times observed for F(ab')/sub 2/ vs IgG and low liver accumulation most likely reflects the absence of hepatic or circulating B6.2 antigen.

• Research Organization: Harvard Medical School, Boston, MA
• OSTI ID: 6593470
• Report Number(s): CONF-840619-
• Conference Information: Journal Name: J. Nucl. Med.; (United States) Journal Volume: 25:5
• Country of Publication: United States
• Language: English

Related Subjects

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550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
59 BASIC BIOLOGICAL SCIENCES
62 RADIOLOGY AND NUCLEAR MEDICINE
ANIMAL TISSUES
ANTIBODIES
BIOMEDICAL RADIOGRAPHY
BLOOD CHEMISTRY
BODY
BONE MARROW
CARCINOMAS
CHEMICAL PREPARATION
COUNTING TECHNIQUES
DIAGNOSIS
DIAGNOSTIC TECHNIQUES
DISEASES
DISTRIBUTION
DRUGS
FUNCTIONS
GLANDS
HEMATOPOIETIC SYSTEM
LABELLED COMPOUNDS
LABELLING
MAMMARY GLANDS
MEDICINE
MONOCLONAL ANTIBODIES
NEOPLASMS
NUCLEAR MEDICINE
ORGANIC COMPOUNDS
ORGANS
PROTEINS
RADIOISOTOPE SCANNING
RADIOLOGY
RADIONUCLIDE KINETICS
RADIOPHARMACEUTICALS
RETENTION FUNCTIONS
SCINTISCANNING
SYNTHESIS
TISSUE DISTRIBUTION
TISSUES
UPTAKE