Preparation and evaluation of para-[211At]astatobenzoyl labeled anti-renal cell carcinoma antibody A6H F(ab′)2. In vivo distribution comparison with para-[125I]iodobenzoyl labeled A6H F(ab′)2

doi:10.1016/0969-8051(93)90092-9

Nuclear Medicine and Biology

Volume 20, Issue 8, November 1993, Pages 917-927

https://doi.org/10.1016/0969-8051(93)90092-9 Get rights and content

Abstract

A preliminary investigation of an ²¹¹At labeled anti-renal cell carcinoma antibody fragment, A6H F(ab′)₂, was conducted. In the investigation, A6H F(ab′)₂ was labeled by conjugation with N-succinimidyl p-[²¹¹At]astatobenzoate, and the in vivo biodistribution was evaluated in athymic mice bearing TK-82 renal cell carcinoma xenografts. As a control, p-[¹²⁵I]iodobenzoyl labeled A6H F(ab′)₂ was coinjected with the astatinated F(ab′)₂. The data obtained demonstrated that the two radiolabels (²¹¹At and ¹²⁵I) had quite similar distributions, providing evidence that the ²¹¹At remained attached to the A6H F(ab′)₂in vivo. Further, the astatinated antibody attained a 2:1 tumor-to-blood ratio, and greater than 35:1 tumor-to-muscle ratio, at 4 h post-injection, suggesting that this antibody conjugate could be used to evaluate treatment of metastatic renal cell carcinoma in a mouse model.

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Preparation and evaluation of para-[211At]astatobenzoyl labeled anti-renal cell carcinoma antibody A6H F(ab′)2. In vivo distribution comparison with para-[125I]iodobenzoyl labeled A6H F(ab′)2

Abstract

Appl. Radiat. Isot.

Int. J. Nucl. Med. Biol.

Int. J. Appl. Radiat. Isot.

Int. J. Appl. Radiat. Isot.

J. Biol. Chem.

Appl. Radiat. Isot.

Analyt. Biochem.

Int. J. Appl. Radiat. Isot.

Int. J. Appl. Radiat. Isot.

Int. J. Nucl. Med. Biol.

Int. J. Radiat. Oncol. Biol. Phys.

Int. J. Appl. Radiat. Isot.

Appl. Radiat. Isot.

The preparation of astatine labeled proteins

Int. J. Appl. Radiat. Isot.

Urinary metabolites of I-131 and Re-186 radiolabeled conjugates of monoclonal antibodies and fragments in patients

J. Nucl. Med.

Isolation and purification of astatine from irradiated targets

Astatine-211 labeling of an antimelanoma antibody and its Fab fragment using N-succinimidyl p-astatobenzoate: comparisons in vivo with the p-[125I]iodobenzoyl conjugate

Bioconj. Chem.

Preparation and evaluation of para-[At-211]astatobenzoate labeled antibodies

J. Nucl. Med.

The accumulation, metabolism, and biological effects of astatine in rats and monkeys

Univ. Calif. Publ. Pharmacol.

Dosimetric aspects of radiolabeled antibodies for tumor therapy

J. Nucl. Med.

The in vitro radiobiology of astatine-211 decay

Radiat. Res.

Preparation and evaluation of para-[²¹¹At]astatobenzoyl labeled anti-renal cell carcinoma antibody A6H F(ab′)₂. In vivo distribution comparison with para-[¹²⁵I]iodobenzoyl labeled A6H F(ab′)₂

Astatine-211 labeling of an antimelanoma antibody and its Fab fragment using N-succinimidyl p-astatobenzoate: comparisons in vivo with the p-[¹²⁵I]iodobenzoyl conjugate