title: TUNEL and limited immunophenotypic analyses of apoptosis in paucibacillary and multibacillary leprosy lesions.
abstract: Some mycobacterial infections, such as tuberculosis, are characterized by apoptosis of infected or by-stander mononuclear immune cells. For localized (paucibacillary, PB) and disseminated (multibacillary, MB) leprosy, characterized by polarized Th1-like vs. Th2-like immune responses, respectively, little is known about lesional apoptosis. We analyzed sections of paraffin-embedded, untreated leprosy lesions from 21 patients by an indirect immunofluorescent terminal deoxynucleotide-transferase-mediated dUTP-digoxigenin nick end labeling (TUNEL) assay. Some TUNEL (+) PB sections were then reacted with phycoerythrin-conjugated (red) antibodies against T cells, monocytes, or antigen-presenting (Langerhans) cells. TUNEL (+) bodies were detected in 9 of 16 PB lesions (56%) and in 1 of 5 MB lesions (20%). Some TUNEL (+) bodies in PB disease were CD3+ (T cell), as well as CD4+ (T-helper) or CD8+ (T-cytotoxic). Apoptosis characterizes PB and MB leprosy lesions and may be more frequent in PB disease. In PB disease, some TUNEL (+) bodies may derive from T cells.
authors.affiliation: Dermatology Service, Eisenhower Army Medical Center, 300 E Hospital Road, Ft. Gordon, GA 30905, USA. douglas.walsh@se.amedd.army.mil
authors.forename: Douglas S
authors.initials: DS
authors.lastname: Walsh
authors.forename: Joshua E
authors.initials: JE
authors.lastname: Lane
authors.forename: Rodolfo M
authors.initials: RM
authors.lastname: Abalos
authors.forename: Khin Saw Aye
authors.initials: KS
authors.lastname: Myint
mesh_terms: D017209:Apoptosis; D006801:Humans; D016130:Immunophenotyping / Q000379:methods*; D020287:In Situ Nick-End Labeling / Q000379:methods*; D007918:Leprosy / Q000276:immunology* / Q000382:microbiology; D009166:Mycobacterium leprae / Q000472:pathogenicity; D013601:T-Lymphocytes / Q000276:immunology / Q000502:physiology