{'fraction_non_alphanumeric': 0.02245088868101029, 'fraction_numerical': 0.0, 'mean_word_length': 5.22093023255814, '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}}
Characterization of a saporin mitotoxin specifically cytotoxic to cells bearing the granulocyte-macrophage colony-stimulating factor receptor.

When granulocyte-macrophage colony-stimulating factor (GM-CSF) is chemically conjugated to the ribosome-inactivating protein saporin, the resulting protein conjugate is highly toxic for cells expressing the GM-CSF receptor. Structural and Western blot analyses of the purified conjugate establish that it contains equimolar amounts of the starting materials and is free of any contamination by the non-conjugated components. The resulting bifunctional reagent is specifically cytotoxic to cells expressing the GM-CSF receptor, but is ineffective to cells that do not express the receptor. The cytotoxic activity is inhibited in a dose-dependent manner by GM-CSF, but not by any one of five other peptide growth factors. This is the first report of a mitotoxin for cells that express the GM-CSF receptor and which promises to be a valuable tool to study the expression of the GM-CSF receptor in normal and pathological states.