Allograft inflammatory factor-1 (AIF-1) is expressed at low levels in normal skin but is upregulated in diverse inflammatory disorders. These comprise such conditions as psoriasis, lichen planus, graft-versus-host-disease, mycosis fungoides and atopic dermatitis. The key cell types expressing AIF-1 are macrophages and Langerhans cells. Retinoic acid and several cytokines (interferon-gamma, IL-1beta, vascular endothelial growth factor) upregulated AIF-1 mRNA levels in monocytic THP-1 and U937 cell lines, while dexamethasone downregulated AIF-1 in U937 cells (Orsmark, C. et al. Acta Derm Venereol 2007, 87(3): 223-227).