Submitted to: Immunology Research Workshop
Publication Type: Abstract Only
Publication Acceptance Date: 10/8/2003
Publication Date: 12/2/2003
Citation: Loving, C.L., Sacco, R.E. 2003. The effects of Pasteurella multocida toxin (pmt) on early murine b-lineage cells. Immunology Research Workshop. December 2, 2003. Interpretive Summary:
Technical Abstract: Pasteurella multocida toxin (PMT) induces pre-osteoclast proliferation and osteoclast differentiation that leads to bone destruction. Developing B-cells and osteoclasts share the same microenvironment; therefore, it is hypothesized that the toxin may elicit alterations in B-cell progenitors in the bone marrow. To test this, mice were exposed to the toxin for 24 hours; peripheral blood, spleen, and bone marrow cells isolated, counted, and developing B-cell populations analyzed by flow cytometry. Toxin exposure resulted in a 5% increase in the percentage of B220**+CD19**+IgM**- cells in the bone marrow, as well as a 5% increase in the percentage of B220**+CD19**+IgM**+ cells in the peripheral blood. Conversely, percentages of B-cell subsets in the spleen were similar in toxin-treated and control mice. The increase in bone marrow B220**+CD19**+IgM**- cells was not due to proliferation as determined by in vivo administration of bromodeoxyuridine (BrdU) during PMT exposure. Furthermore, PMT did not alter the expression of the anti-apoptotic Bcl-2 as measured by intracellular staining. As B220**+ cells have been shown to serve as osteoclast precursors, we are currently investigating whether PMT induces osteoclastogenesis of bone marrow B220**+CD19**+IgM**- cells.