(a)Ability to induce antimicrobial peptides (AMPs) as evidenced by lesional minus nonlesional expression analysed by quantitative reverse transcriptase–polymerase chain reaction (RT-PCR). Skin biopsy samples from lesional and nonlesional skin of subjects were collected and analysed for expression of AMPs. Values of the AMPs were normalized to the housekeeping gene glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and the data plotted are presented as relative AMP expression. Differences separated by diagnostic group reveal cathelicidin expression in patients with atopic dermatitis (AD) with a history of eczema herpeticum (ADEH) to be significantly depressed compared with patients with AD (P = 0.014) or psoriasis (P = 0.001). (b) Ability to induce human β-defensin (HBD)-2 as evidenced by lesional minus nonlesional expression, analysed by quantitative RT-PCR and normalized to the housekeeping gene GAPDH reveal HBD-2 to be significantly suppressed in patients with ADEH in comparison to those with AD (P = 0.003) or psoriasis (P < 0.001). (c) Ability to induce HBD-3 as evidenced by lesional and nonlesional differences, analysed by quantitative RT-PCR and normalized to the housekeeping gene GAPDH reveal HBD-3 expression in patients with ADEH to be depressed compared with that in patients with psoriasis (P = 0.003), while showing a trend towards lower levels than subjects with AD (P = 0.06). (a–c) Differences were calculated using the ΔΔCt method (see Supporting information).

(a) Nonlesional skin values for cathelicidin analysed by quantitative reverse transcriptase–polymerase chain reaction (RT-PCR) and normalized to the housekeeping gene glyceraldehyde 3-phosphate dehydrogenase (GAPDH) revealed no significant differences between the four groups. (b) Analysis of human β-defensin (HBD)-2 in nonlesional skin revealed significantly higher HBD-2 levels in subjects with atopic dermatitis (AD) with a history of eczema herpeticum (ADEH) compared with patients with AD (P < 0.001) or psoriasis (P < 0.001), or normal control subjects (P = 0.001). (c) Analysis of HBD-3 in nonlesional skin revealed significantly higher HBD-3 levels in subjects with ADEH compared with those with AD (P = 0.002) or psoriasis (P = 0.003). CATH, cathelicidin; NonLes, nonlesional; Psor, psoriasis; Cont, control.