Localization of 131I-labeled p97-specific Fab fragments in human melanoma as a basis for radiotherapy.

The effects of 131-labelled antiferritin polyclonal antibody for the treatment of established hepatocellular carcinoma (HC-04) in athymic nude mice were evaluated. 131I-labelled antiferritin antibody localised specifically to a subcutaneous tumour with a mean of 8.1% of the infused dose per gram of tumour at 24 h after infusion when the experiment was started 15 days after inoculation and with a mean of about 6.5% of the infused dose per gram of tumour when the experiment was started 30 days after tumour transplantation. The concentrations of 131I-antiferritin antibody in tumour delivered a mean of 1994 cGy to tumour following infusion of 500 microCi of radiolabelled antiferritin antibody in the early group and a mean of 1600 cGy in the late group. Treatment with 500 microCi led to regression of the tumour in 55% of animals in the early group and 44% in the late group. In contrast, unlabelled antiferritin and 131I-labelled IgG failed to exert any significant effect on tumour growth. The transplanted tumours in the early groups of animals had relatively higher concentration of ferritin than those in the late group. There was accelerated inhibition of tumour growth and prolonged survival in animals in the early group compared with those in the late group.

Section: Discussionmentioning

confidence: 95%

Radioimmunotherapy of human hepatocellular carcinoma xenografts with 131I-labelled antiferritin antibody

Alam

1991

“…In most of these studies complete remission was only achieved when antibody treatment was administered within 24 h of tumour transplantation or by injecting a lethal amount of radiation. Attempts at experimental therapies have also been reported with '3'I-labelled fragments (Larson et al, 1983;Blumenthal et al, 1989;Buchegger et al, 1989;Pedley et al, 1993).…”

Section: Discussionmentioning

confidence: 99%

Radioimmunotherapy of colorectal carcinoma xenografts in nude mice with yttrium-90 A33 IgG and Tri-Fab (TFM)

Antoniw

Farnsworth²,

Turner³

et al. 1996

“…Unfortunately, the latter half-life is not easily measured, but can be expected to vary greatly from one tumour to the next Rostock et al, 1984;Klein et al, 1985). Larson et al (1983) have reported an effective halflife (composite of biological and physical half-lives) of 46 h in melanoma following injection of a patient with 1311-labelled Fab fragments of an antimelanoma McAb. Using 131I-labelled antiferritin polyclonal antibody, Leichner and his colleagues (1983) reported effective half-lives within the patient's primary hepatoma of between 0.25 and 7.8 days -depending upon the method of purification and the subsequent diluent of the administered antibody.…”

Section: Carriermentioning

confidence: 99%

Radioimmunotherapy of malignancy using antibody targeted radionuclides

Cobb¹,

Humm²

1986

Summary Antibodies directed against tumour associated antigens provide a means for delivering preferentially cytotoxic radionuclides to the cells of primary and secondary tumours. The factors that influence the effectiveness of the radiation in the tumour compared with its effect on the radiosensitive normal tissues include the specificity of the antibody, the distribution of targeted energy within the tumour and the host's response to the injected foreign antibody. Recently some encouraging results from clinical trials of radioimmunotherapy have been reported in the literature. There is a continual search for more avid and specific antibodies, and the techniques of genetic engineering are being applied to the problem of reducing the antigenicity and mass of the carrier antibody. The improved efficiency of the labelled antibody needs to be supplemented by an identification of those tumours most likely to respond to this form of therapy.