An immunohistochemical study of CD4, CD8, TIA‐1 and CD56 subsets in inflammatory skin disease

Background:  Antibodies to CD4, CD8, TIA‐1, and CD56 are available which perform well in formalin‐fixed and paraffin‐embedded tissue. While previous studies have investigated CD4 and CD8 subsets in inflammatory skin disease, few have specifically addressed TIA‐1 and CD56 reactivity in benign dermatoses. Given that CD8, TIA‐1, and CD56 are linked to aggressive lymphoproliferative disorders (i.e. subcutaneous panniculitic T‐cell lymphoma, natural killer (NK), and NK/T‐cell lymphomas), it would be important to determine their specificity for cutaneous hematologic malignancies. This investigation was undertaken to determine the frequency with which common, benign dermatoses express these four markers. We also sought to determine whether the ratio of CD4‐ to CD8‐positive cells could be used to distinguish among the dermatoses, especially the superficial and deep perivascular ones.