The CD14+CD16+ monocytes in erysipelas are expandend and show reduced cytokine production.

Abstract

In human peripheral blood the classical CD14++DR+ monocytes and the pro-inflammatory CD14+CD16+DR++ monocytes can be distinguished. In erysipelas we found strongly increased numbers of CD14+CD16+ monocytes on the day of diagnosis (day 1) in 11 patients with an average of 150.5±76.0 cells/μl, while 1 patient had low levels (35 cells/μl, control donors 48.8±19.8 cells/μl). The classical monocytes were only moderately elevated in the erysipelas patients (factor 1.7 as compared to controls). Patients exhibited increased body temperature, erythrocyte sedimentation rate and increased serum levels for C-reactive protein (CRP), IL-6 and macrophage-colony-stimulating factor. Among these, body temperature and CRP showed a significant correlation to the numbers of CD14+CD16+ monocytes. In 4 of 4 patients with high levels of CD14+CD16+ monocytes, these levels returned to that seen in controls by day 5 of antibiotic therapy. Determination of intracellular TNF was performed by three-color immunofluorescence and flow cytometry after ex vivo stimulation withlipoteichoic acid, a typical constituent of streptococci. Here, patient CD14+DR++ pro-inflammatory monocytes showed a twofold lower level of intracellular TNF. By contrast, expression of TNF was unaltered in the classical CD14++ monocytes. These data show that in erysipelas the pro-inflammatory CD14+CD16+DR++ monocytes are substantially expanded and selectively tolerant to stimulation by streptococcal products. &nbsp