{'fraction_non_alphanumeric': 0.018102372034956304, 'fraction_numerical': 0.0024968789013732834, 'mean_word_length': 5.386454183266932, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Antibody Treatment May Replace Toxic Conditioning Regimens for Hematopoietic Stem Cell Transplantation: ‘Animal Study, But Strong Proof of Principle’

Treatment with a monoclonal antibody may be enough to prepare patients for hematopoietic stem cell transplantation in the future, if data from animal models bears out. Stanford researchers reporting data at the ASH Annual Meeting found that administration of an antibody that binds to C-kit, a protein that is abundantly expressed on the surface of hematopoietic stem cells, eliminated 98% of the endogenous hematopoietic stem cells in mice. Transplantation of stem cells several days later from untreated donor animals resulted in 90% chimerism. Experts interviewed for this article agree that although the work is early, it represents an important new way of thinking about pretransplant conditioning, and may lead to regimens that are much easier for patients. “We have shown that a finite number of hematopoietic stem cell niches are available for engraftment at any point in time, and that simply transplanting more cells does not overcome this barrier,” said Agnieszka Czechowicz, a medical student at Stanford School of Medicine, who presented the new research. “One way to overcome this barrier is to actively eliminate the host stem cells before the transplant. We can do this by specifically depleting the host hematopoietic stem cells with a specific antibody. By doing this we eliminate that need for chemotherapy and radiation, toxic conditioning regimens that currently prevent widespread use of hematopoietic stem cell transplantation.”