Restoration of defective cytokine activity within lepromatous leprosy lesions.
Immunohistological studies of tuberculoid leprosy lesions (TT-lesions) showed a dense, well organized granuloma consisting of a central area with epitheloid and giant cells containing interferon-gamma (IFN-Gamma) and CD3+, CD4+ T helper/inducer (Th/i) cells, a considerable proportion of which expressed the interleukin-2-receptor (IL-2 R). This central area was surrounded by round cells which consisted mainly of CD3+/CD8+ T cytotoxic/suppressor (Tc/s) lymphocytes. The overlying keratinocytes (KC) were strongly positive for HLA-DR antigens on the surface, indicating high intralesional IFN-Gamma activity. In contrast, lepromatous leprosy lesions (LL-lesions) showed a disorganized infiltrate composed by foamy cells and round cells, the latter mainly expressing the CD3+/CD8+ phenotype. IFN-Gamma activity could not be detected within the lesions. The KC overlying the infiltrate were consistently negative for HLA/DR reactivity pointing to a defective intralesional IFN-Gamma production in LL patients. Two out of four patients with LL leprosy could be sensitized with dinitrochlorobenzene (DNCB). The eliciting of DNCB skin reactions within the LL-lesion led to the recruitment of new infiltrating cells; the resulting infiltrate resembled a local reversal towards the tuberculoid pole of leprosy.
Volc-Platzer
B
B
Univ. Hautklinik, Wien.
Kremsner
P
P
Stemberger
H
H
Wiedermann
G
G
D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D003713:Dendritic Cells / Q000276:immunology; D004137:Dinitrochlorobenzene / Q000494:pharmacology; D005487:Foam Cells / Q000276:immunology; D006099:Granuloma / Q000276:immunology / Q000473:pathology; D006684:HLA-DR Antigens / Q000032:analysis*; D006801:Humans; D006968:Hypersensitivity, Delayed; D007111:Immunity, Cellular; D007150:Immunohistochemistry; D007371:Interferon-gamma / Q000032:analysis*; D015603:Keratinocytes / Q000276:immunology*; D015440:Leprosy, Lepromatous / Q000276:immunology* / Q000473:pathology; D015441:Leprosy, Tuberculoid / Q000276:immunology / Q000473:pathology; D008264:Macrophages / Q000276:immunology; D015375:Receptors, Interleukin-2 / Q000032:analysis*; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology
D004137:Dinitrochlorobenzene; D006684:HLA-DR Antigens; D015375:Receptors, Interleukin-2; D007371:Interferon-gamma