Functional analysis of T lymphocytes infiltrating the dermis and epidermisof post-burn hypertrophic scar tissues

The cytokine profile of T cell clones (TCC) from the dermis and epidermis o f burn patients with hypertrophic scars (HS) in active (AHS) and remission phases (RHS) was determined in this study. We found that AHS tissues are he avily infiltrated by Type 0-Type 1 polarized CD3(+) lymphocytes producing h igh IFN-gamma and low IL-4 levels. Analysis of their surface marker phenoty pe showed that the high IFN-gamma production was shared equally between the CD4(+) TCR alpha/beta and CD8(+) TCR alpha/beta clones, The profile of TCC from RHS tissues revealed pronounced infiltration of Type 0-Type I polariz ed lymphocytes with an even more evident Type 1 profile. However, the level s of IFN-gamma produced by RHS-derived TCC were 4-6 times lower than those produced by AHS-derived TCC. These data show that high levels of IFN-gamma produced by Type 0-Type I lymphocytes infiltrating HS are a feature of AHS, whereas reduction of this ability to produce high levels of IFN-gamma, tho ugh without a shift towards a Type 0-Type 2 phenotype through an increase i n IL-4, is characteristic of RHS, (C) 1999 Elsevier Science Ltd and ISBI. A ll rights reserved.