Differential effects of Francisella tularensis lipopolysaccharide on B lymphocytes.

Autor: Rahhal RM; Department of Pediatrics, University of Iowa, Iowa City, IA 52242, USA., Vanden Bush TJ, McLendon MK, Apicella MA, Bishop GA
Jazyk: angličtina
Zdroj: Journal of leukocyte biology [J Leukoc Biol] 2007 Oct; Vol. 82 (4), pp. 813-20. Date of Electronic Publication: 2007 Jul 18.
DOI: 10.1189/jlb.1206765
Abstrakt: Francisella tularensis, a designated Category A biological agent, can cause severe infection in humans. Previous studies have demonstrated a significant immunoprotective role for B lymphocytes in animal models, but the responses of human B lymphocytes to F. tularensis components are largely unknown. The LPS of F. tularensis is atypical and has been reported to lack biological activity on myeloid cells and mouse B cells. Our study characterized the immunological effects of highly purified LPS from different stains of F. tularensis on human B lymphocytes and compared these effects with those on mouse B cells and human monocyte-derived macrophages. Results indicate that marked differences exist between cell type and species in specific responses to this interesting bacterial component. In sharp contrast to responses of mouse splenic B cells or human macrophages, human peripheral B cells showed reproducibly elevated IL-6, TNF-alpha, and antibody production in response to F. tularensis LPS. Data also indicated that these activated human B lymphocytes may subsequently promote the activation of other immune cell types by direct cell-cell interaction. Further investigation into the potential usefulness of F. tularensis LPS as an adjuvant component of a more optimal subunit vaccine is warranted, as it is now clear that it is not biologically inactive, as assumed previously.
Databáze: MEDLINE