Cytokines in murine lyme carditis: Th1 cytokine expression follows expression of proinflammatory cytokines in a susceptible mouse strain

Mittie Kelleher Doyle, Harvard School of Public Health
Sam R. Telford 3rd, Harvard School of Public Health
Lisa Criscione, Harvard School of Public Health
Shin Ru Lin, Harvard School of Public Health
Andrew Spielman, Harvard School of Public Health
Ellen M. Gravallese, University of Massachusetts Medical School

At the time of publication, Ellen Gravallese was not yet affiliated with the University of Massachusetts Medical School.

Abstract

The cardiac infiltrate seen in murine Lyme carditis is composed predominantly of macrophages, but small numbers of T cells are also present. To identify the cytokines present in cardiac lesions from susceptible mice, semiquantitative polymerase chain reaction was done on cardiac tissue from mice infected with Borrelia burgdorferi. The temporal expression of proinflammatory and T cell-derived cytokines was characterized in cardiac tissue at days 0, 3, 7, 14, 21, and 42 after infection with B. burgdorferi. Early in the course of infection, up-regulation of the proinflammatory cytokines interleukin-1beta and tumor necrosis factor-alpha was detected. The Th1 cytokine interferon-gamma appeared after the expression of the proinflammatory cytokines and remained elevated throughout the study. Interleukin-4 was not detectable at any time in cardiac lesions. These data are the first to identify cytokines expressed at the lesional level in murine Lyme carditis and to demonstrate a Th1 pattern of cytokine expression in this lesion.