A new approach to quantification of DTPA incorporation into monoclonal antibodies (MoAbs) labeled by the cyclic anhydride DTPA method

Conference · Wed May 01 04:00:00 EDT 1985 · J. Nucl. Med.; (United States)

OSTI ID:6856753

Wang, T S.T.; Ng, A K; Fawwaz, R A; Alsedairy, S; Alderson, P O

A method for determining the ratio of DTPA molecules attached per molecule of Ab was developed and used to examine the immunoreactivity of different Abs as a function of the amount of incorporated DTPA. The bicyclic anhydride of DTPA(2-C-14)acetic acid (BADTPA-C-14) was synthesized by reacting DTPA(2-C-14)acetic acid (1mCi/mmo1) and acetic anhydride. BADTPA-C-14 then was reacted with a MoAb to a melanoma associated antigen (MA) and to a MoAb to human HLA class II antigen (HLA) at 2mg/m1 of MoAb concentration, at MoAb to BADTPA-C-14 ratios (mmo1/mmo1) of l:1, 1:10, 1:00, l:200. The conjugate was dialyzed exhaustively against HEPES at pH 7.0. The MoAb concentration was measured at 280mm of uv; the DTPA/MoAb ratio was calculated based on the specific activity of BADTPA-C-14, and the immunoreactivity was assessed by direct cell-binding to melanoma, the HLA antigen and control (lymphoma) cells. Percent binding to the lymphoid cell line was less than 3%. The authors' results demonstrated a method for directly determining the number of DTPA molecules attached to a MOAb, and demonstrated variations in immunoreactivity as the number of DTPA groups per MoAb is altered.

• Research Organization: Columbia Univ., New York, NY
• OSTI ID: 6856753
• Report Number(s): CONF-850611-
• Conference Information: Journal Name: J. Nucl. Med.; (United States) Journal Volume: 26:5
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
AMINO ACIDS
ANTIBODIES
ANTIGENS
BIOCHEMISTRY
CARBON 14 COMPOUNDS
CARBOXYLIC ACIDS
CHELATING AGENTS
CHEMICAL PREPARATION
CHEMISTRY
COUNTING TECHNIQUES
DIAGNOSTIC TECHNIQUES
DISEASES
DISTRIBUTION
DRUGS
DTPA
IMMUNOLOGY
LABELLED COMPOUNDS
LABELLING
LYMPHOMAS
MEDICINE
METABOLISM
MONOCLONAL ANTIBODIES
NEOPLASMS
NUCLEAR MEDICINE
ORGANIC ACIDS
ORGANIC COMPOUNDS
RADIOCHEMISTRY
RADIOIMMUNOLOGY
RADIOIMMUNOTHERAPY
RADIOISOTOPE SCANNING
RADIOLOGY
RADIONUCLIDE KINETICS
RADIOPHARMACEUTICALS
RADIOPROTECTIVE SUBSTANCES
RADIOTHERAPY
SCINTISCANNING
SYNTHESIS
THERAPY
TISSUE DISTRIBUTION