The hepatic stem cell niche: identification by label-retaining cell assay.

Unlabelled: Label retention assays remain the state-of-the-art approach to identify the location of intraorgan epithelial stem cell niches, in situ and in vivo. They are commonly used in organs with rapid cell turnover but have not been applied to the liver, where cell turnover is very slow. We used a sublethal dose of acetaminophen administered coincident with bromodeoxyuridine to load possible hepatic stem cells in mice with label and then administered a second, sublethal chase of acetaminophen to accomplish "washout" of label from transit amplifying cell populations.

Radioimmunotherapy for model B cell malignancies using 90Y-labeled anti-CD19 and anti-CD20 monoclonal antibodies.

In recent years, radioimmunotherapy (RIT) with beta(-) particle emitting radionuclides targeting the CD20 antigen on B cells in the treatment of non-Hodgkin's lymphoma has provided the most compelling human clinical data for the success of RIT. CD19, like CD20, is an antigen expressed on the surface of cells of the B lineage, and CD19 may provide an alternative target for radioimmunotherapy of B cell neoplasms. CD19 has been largely overlooked as a target for conventional 131I RIT, because the antigen rapidly internalizes upon binding of antibody, resulting in catabolism and significant release of 131I.

Relative therapeutic efficacy of (125)I- and (131)I-labeled monoclonal antibody A33 in a human colon cancer xenograft.

Unlabelled: A33, a monoclonal antibody that targets colon carcinomas, was labeled with (125)I or (131)I and the relative therapeutic efficacy of the 2 radiolabeled species was compared in a human colon cancer xenograft system.

Methods: Nude mice bearing human SW1222 colon carcinoma xenografts were administered escalating activities of (125)I-A33 (9.25-148 MBq) or (131)I-A33 (0.

An alpha-particle emitting antibody ([213Bi]J591) for radioimmunotherapy of prostate cancer.

A novel alpha-particle emitting monoclonal antibody construct targeting the external domain of prostate-specific membrane antigen (PSMA) was prepared and evaluated in vitro and in vivo. The chelating agent, N-[2-amino-3-(p-isothiocyanatophen-yl)propyl]-trans-cyclohexane-1, 2-diamine-N,N',N',N'',N''-pentaacetic acid, was appended to J591 monoclonal antibody to stably bind the 213Bi radiometal ion. Bismuth-213 is a short-lived (t 1/2 = 46 min) radionuclide that emits high energy alpha-particles with an effective range of 0.

131I radioimmunotherapy and fractionated external beam radiotherapy: comparative effectiveness in a human tumor xenograft.

Unlabelled: This article compares the effectiveness of radiation delivered by a radiolabeled monoclonal antibody, 131I-labeled A33, that targets colorectal carcinoma, with that of 10 fractions of conventional 320 kVp x-rays.

Methods: Human colorectal cancer xenografts (SW1222) ranging between 0.14 and 0.