Altered interleukin-6 expression in fibroblasts from hypertrophic burn scars.

Hypertrophic burn scars (HBSs) are characterized by a net accumulation of collagen. The role of growth factors and various cytokines in the pathogenesis of these lesions has not been fully characterized. Interleukin-6 (IL-6) is an important immunoregulatory cytokine that can affect fibroblast function. This study showed increased expression of the IL-6 gene in fibroblasts isolated from patients with HBSs compared with control fibroblasts when the ribonuclease protection assay was used. A subsequent increase in unstimulated and stimulated IL-6 secretion was noted in HBS fibroblasts compared with normal control fibroblasts (unstimulated, 0.3627+/-0.2017 pg/cell vs 0.0662+/-0.0786 pg/cell, P = .0054; serum, 0.770+/-0.523 pg/cell vs 0.233+/-0.231 pg/cell, P = .0381; serum and interferon-gamma, 0.912+/-0.650 pg/cell and 0.244+/-0.199 pg/cell, P = .0327). These results are further evidence of the role of inflammatory cytokines in the development of HBSs.