Targeting CD33 or CD45 is currently exploited for immunotherapy of acute myeloid leukemia (AML). Gemtuzumab ozogamicin (GO), an immunoconjugate of an anti-CD33 antibody that facilitates cellular uptake of a toxic calicheamicin-gamma(1) derivative, induces complete remissions in a subset of patients with AML. We herein tested whether simultaneous targeting of CD45 could improve GO cytotoxicity a...

The present study showed that the HIS-C7 monoclonal antibody, which recognizes the chick form of CD45, is a specific marker for macrophages/microglial cells in the developing and mature chick central nervous system (CNS). HIS-C7-positive cells were characterized according to their morphological features and chronotopographical distribution patterns within developing and adult CNS, similar to th...

It has been reported that ligation of CD40 with CD40 ligand (CD40L) results in microglial activation as evidenced by p44/42 mitogen-activated protein kinase (MAPK) dependent tumor necrosis factor alpha (TNF-alpha) production. Previous studies have shown that CD45, a functional transmembrane protein-tyrosine phosphatase, is constitutively expressed at moderate levels on microglial cells and this...

Iodine-131-labeled anti-CD45 antibody has been added to conventional hematopoietic stem cell transplant preparative regimens to deliver targeted radiation to hematopoietic tissues, with the goal of decreasing relapse rates without increasing toxicity. However, higher radiation doses could be delivered to leukemia cells by antibody if the systemic therapy were decreased or eliminated. To examine...

UNLABELLED Radioimmunotherapy is a method to selectively deliver radioactivity to cancer cells via specific antibodies. A strategy to enhance the efficacy of radioimmunotherapy is the prior application of unlabeled antibody, resulting in an increase in the dose to the target tissue and a decrease in the burden to other organs. It was suggested that optimizing this approach might considerably im...

Anti-CD45 monoclonal antibodies (mAbs) are potentially powerful tools for the depletion of mature leukocytes. As their application for immunotherapy also depends on their effects on bone marrow (BM) progeny, the in vivo effects of an anti-CD45 mAb (anti-RT7(a) mAb) on BM precursor cells were analyzed in a rat model. Anti-RT7(a) mAb treatment was performed in LEW.1W (RT1(u) RT7(a)) rats with the...

A flow cytometric method for the identification of chicken blood leukocyte subpopulations and thrombocytes was developed. An anti-chicken CD45 phycoerythrin-labelled antibody was used to separate leukocytes from red blood cell nuclei. Leukocytes and thrombocytes were identified using a combination of their CD45-positivity and their typical side scatter properties. The identity of the CD45-posit...

Delivery of targeted hematopoietic irradiation using radiolabeled monoclonal antibody may improve the outcome of marrow transplantation for advanced acute leukemia by decreasing relapse without increasing toxicity. We conducted a phase I study that examined the biodistribution of 131I-labeled anti-CD45 antibody and determined the toxicity of escalating doses of targeted radiation combined with ...

The ability to deliver radiation selectively to lymphohematopoietic tissues may have utility in conditions treated by myeloablative regimens followed by bone marrow transplantation. Since the CD45 antigen is the most broadly expressed of hematopoietic antigens, we examined the biodistribution of radiolabeled anti-CD45 monoclonal antibodies in normal mice. Trace 125I or 131I-labeled monoclonal a...

Currently, there is extensive information about circulating tumor cells (CTC) and their prognostic value; however, little is known about other characteristics of these cells. In this prospective study, we assessed the gene transcripts of epithelial-to-mesenchymal transition-inducing transcription factors (EMT-TF) and cancer stem cell (CSC) features in patients with HER2(+) metastatic breast can...