Synthesized Growth Factors Increase WBC Proliferation After Chemotherapy and Radiation

Chemotherapy destroys healthy white blood cells (WBC) and their precursor stem cells in bone marrow, resulting in bacterial infections. At high dosages, total body radiation also causes a significant decrease in WBC and leads to neutropenia. Granulocyte colony-stimulating factor (G-CSF) and granulocyte macrophage colony-stimulating factor (GM-CSF) stimulate growth and proliferation of WBC, and therefore are used as adjunct treatments alongside chemotherapy and radiation. Currently, the expenditure for G-CSF and GM-CSF production is $6 billion annually, and those proteins are large, relatively unstable, difficult to synthesize and problematic to stockpile for radiation emergencies. The goal of this project is to identify and test synthetic peptides for their ability to stimulate leukocyte proliferation in vitro. .The amino acid sequences represent a fragment of a non-CSF peptide shown to increase WBC growth. We hypothesized that these synthesized peptides will increase human WBC proliferation in vitro. For this study, AML-193, HL-60 and Molt-4 human WBC cell lines were plated at low densities and allowed to grow for 72 hours. Growth curves to determine saturation, optimal growth and cell density were generated. Subsequently, the cell lines will be treated with peptide drugs at various concentrations, determining cell growth and proliferation. Should our results demonstrate that these peptides are indeed active, they will be candidates for an inexpensive, stable alternative or additives to G-CSF and GM-CSF, readily available at the hospitals as post-radiation and chemotherapy adjunct treatment in preventing infections.