title: Dysregulation of IL-4 expression in lepromatous leprosy patients with and without erythema nodosum leprosum.
abstract: In order to increase our understanding of the immunological basis of erythema nodosum leprosum (ENL), we studied Th-like cytokine profiles in 130 leprosy patients, employing both the conventional and a novel, real-time, fluorogenic reverse transcriptase-based PCR (RT-PCR). The concomitant expression of both Th-like cytokines, interferon-gamma and IL-4, and the regulatory cytokines, IL-10 and IL-12, was studied in the peripheral blood cells of leprosy patients with and without ENL. In the conventional RT-PCR, varied cytokine profiles were observed in individual patients of all clinical types. Fifty-three percent of lepromatous patients without ENL and 59% of tuberculoid leprosy patients showed co-expression of IFN gamma and IL-4, indicating a non-polarized Th 0 pattern. Of the 36 patients with ENL, 58% demonstrated a polarized Th 1 pattern, with only 30% expressing both cytokines. Semiquantitative RT-PCR indicated a lower expression of IL-4 compared to that of IFN gamma in the lepromatous patients without ENL; the difference was even greater among those with ENL. The sensitive, real-time PCR confirmed the down-regulation of IL-4 and IL-10, with absence of IL-4 in half of the patients, resulting in skewing of the cytokine response toward a Th 1-like profile.
authors.affiliation: Department of Biotechnology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: I
authors.initials: I
authors.lastname: Nath
authors.forename: N
authors.initials: N
authors.lastname: Vemuri
authors.forename: A L
authors.initials: AL
authors.lastname: Reddi
authors.forename: M
authors.initials: M
authors.lastname: Bharadwaj
authors.forename: P
authors.initials: P
authors.lastname: Brooks
authors.forename: M J
authors.initials: MJ
authors.lastname: Colston
authors.forename: R S
authors.initials: RS
authors.lastname: Misra
authors.forename: V
authors.initials: V
authors.lastname: Ramesh
mesh_terms: D016207:Cytokines / Q000502:physiology; D015536:Down-Regulation; D004797:Enzyme-Linked Immunosorbent Assay; D004893:Erythema Nodosum / Q000150:complications / Q000175:diagnosis*; D005260:Female; D006801:Humans; D015847:Interleukin-4 / Q000502:physiology*; D015440:Leprosy, Lepromatous / Q000150:complications / Q000175:diagnosis*; D015441:Leprosy, Tuberculoid / Q000150:complications / Q000175:diagnosis*; D008297:Male; D012016:Reference Values; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity
chemical_list: D016207:Cytokines; D015847:Interleukin-4