title: Photofrin, but not benzoporphyrin derivative, stimulates hematopoiesis in the mouse.
abstract: This report describes the effects of the porphyrin photosensitizers, Photofrin and benzoporphyrin derivative (BPD) on the immunohematopoietic system of normal and immunosuppressed DBA/2 mice in the absence of activating light. Photofrin (10 and 25 mg/kg) significantly increased in vitro colony formation by cells of the granulocyte-macrophage lineage in the spleen and bone marrow. Splenic hypercellularity, splenomegaly and elevated levels of blood leukocytes were observed in these mice 7 days following Photofrin injection. Evidence that Photofrin influenced the lymphohematopoietic compartment was suggested by a significant increase in blood lymphocytes and a population of spleen cells identified by a monoclonal antibody (LR-1) reactive with mouse splenic B lymphocytes. Proliferative responses of spleen cells from Photofrin-treated mice to sub-optimal concentrations of Con A were greater than that observed for controls. However, spleen cell responses to LPS were unaltered by Photofrin administration. In contrast, BPD (10 mg/kg) did not alter any of the immunohematopoietic parameters studied. When Photofrin was administered to mice treated with the myeloablative agent 5-FU there was a significant acceleration in the recovery of total blood leukocyte and spleen cell numbers, relative to the controls. These studies demonstrate that, in addition to its previously documented activities as a photosensitizer, Photofrin can exert stimulatory effects upon murine hematopoiesis.
authors.affiliation: Department of Microbiology, University of British Columbia, Vancouver, Canada.
authors.forename: D W
authors.initials: DW
authors.lastname: Hunt
authors.forename: R A
authors.initials: RA
authors.lastname: Sorrenti
authors.forename: C B
authors.initials: CB
authors.lastname: Smits
authors.forename: J G
authors.initials: JG
authors.lastname: Levy
mesh_terms: D000818:Animals; D001853:Bone Marrow / Q000187:drug effects*; D001854:Bone Marrow Cells; D002452:Cell Count / Q000187:drug effects; D002478:Cells, Cultured; D003114:Colony-Forming Units Assay; D003208:Concanavalin A / Q000494:pharmacology; D017323:Dihematoporphyrin Ether / Q000494:pharmacology*; D005472:Fluorouracil / Q000494:pharmacology; D006410:Hematopoiesis / Q000187:drug effects*; D007165:Immunosuppression Therapy; D007958:Leukocyte Count / Q000187:drug effects; D008027:Light; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D051379:Mice; D008811:Mice, Inbred DBA; D011166:Porphyrins / Q000494:pharmacology*; D013154:Spleen / Q000166:cytology / Q000187:drug effects*
chemical_list: D008070:Lipopolysaccharides; D011166:Porphyrins; D003208:Concanavalin A; C504224:benzoporphyrin D; D017323:Dihematoporphyrin Ether; D005472:Fluorouracil