Interleukin-15 Expression in Atherosclerotic Plaques

• DOI: 10.1161/hq0701.092162
• Publication Date: 2007-09-28T18:27:24Z
• Authors: Mischa A. Houtkamp; Allard C. van der...; Onno J. de Boer; Chris M. van der ...; Piet A. J. de Boer; Antoon F. M. Moorman; Anton E. Becker
• Keywords: Colocalization

T-cell activation in atherosclerotic plaques is thought to be initiated by plaque-derived antigens, such as oxidized LDL (oxLDL). An alternative pathway of independent antigen stimulation, mediated the cytokine interleukin (IL)-15, was recently described. We investigated IL-15 expression relation plaque morphology, inflammatory cells, activation, and oxidation-specific epitopes use immunohistochemistry. In situ hybridization used evaluate mRNA expression. also studied proliferative response lines vitro using [(3)H]thymidine incorporation. Fresh-frozen specimens were classified fibrous (n=9), fibrolipid (n=8), lipid-rich (n=14) plaques; normal vessels (n=4) served reference. Expression protein found almost solely plaques, associated with oxLDL-positive macrophages. Sequential immunostains revealed colocalization between IL-15- CD40L-positive T cells. Moreover, highly responsive IL-15. Hence, could provide a for antigen-independent activation.