These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Effects of in vivo treatment with PIXY321 (GM-CSF/IL-3 fusion protein) on proliferation kinetics of bone marrow and blood myeloid progenitor cells in patients with sarcoma.
    Author: Broxmeyer HE, Benninger L, Cooper S, Hague N, Benjamin RS, Vadhan-Raj S.
    Journal: Exp Hematol; 1995 Apr; 23(4):335-40. PubMed ID: 7895781.
    Abstract:
    PIXY321, a stimulator of multipotent colony-forming units (CFU-GEMM), burst-forming unit-erythroid (BFU-E), and colony-forming units granulocyte/macrophage (CFU-GM) progenitor cell proliferation in vitro, is currently being assessed in phase-I/-II clinical trials. We evaluated kinetics of CFU-GEMM, BFU-E, and CFU-GM proliferation in bone marrow (BM), blood, and granulocyte (CFU-G) and macrophage (CFU-M) progenitors in BM of chemotherapy-naive patients with sarcoma-administered PIXY321 (25 to 1000 micrograms/m2/day subcutaneously for 14 days). BM and/or blood cells from three to four patients at each dosage were assessed before, during, 1 to 2 days, and 7 days following treatment with PIXY321. Cells were pulse-treated in vitro with or without high-specific activity tritiated thymidine (3H-dThr) (to assess the percentage of progenitors in S-phase of cell cycle) and cultured for immature and more mature subsets of CFU-GEMM, BFU-E, CFU-GM, and for CFU-G and CFU-M. Despite heterogeneity in baseline cycling status of progenitors in BM, administration of 125 to 500 micrograms PIXY321 to patients at least doubled (p < 0.001) cycling rates of all BM progenitors. The cycling rates of blood progenitors increased from a slow or non-cycling state to > 38% cells in cycle. Within 1 to 2 days after cessation of PIXY321 infusion, all progenitors were in a slow or noncycling phase below that of many of the pre-BM samples (immature and mature CFU-GM and mature BFU-E) or were back to background levels (CFU-G, CFU-M, CFU-GEMM, and immature BFU-E). These cycling effects were similar to those previously noted for BM CFU-GM and BFU-E in patients on clinical trial with GM-CSF. In contrast, higher dosages of PIXY321, especially 1000 micrograms, increased cycling of BM and blood progenitor cells early during treatment, but cycling rates decreased while patients were still being administered PIXY321; decreased cycling was maintained after cessation of PIXY321. PIXY321 is thus highly active in vivo as a stimulator of multipotential and more lineage-restricted progenitors. The kinetics of progenitor cell proliferation noted in this study highlight differences seen with GM-CSF and G-CSF. The effects described here could be of relevance in design of future clinical trials using PIXY321 as an adjunct treatment in patients undergoing cytoreductive therapy.
    [Abstract] [Full Text] [Related] [New Search]