title: Effects of formaldehyde and xylene on CD4- and CD8-positive T cells in bronchus-associated lymphoid tissue in rats.
abstract: The aim of this study was to determine the localization and number of CD4- and CD8-positive T lymphocytes in bronchus-associated lymphoid tissue (BALT) of the embryos and newborns or young and adult rats exposed to formaldehyde (6 ppm), technical xylene (300 ppm), or a combination of these two agents (3 ppm + 150 ppm) for 6 weeks (8 h/day). A total of 96 female Sprague-Dawley rats were used. The CD4-positive cells were localized predominately in area under the epithelium and in the periphery of BALT follicles after the exposure period. However, CD8-positive cells were localized mainly in the periphery of BALT follicles after the exposure period. The number of CD4- and CD8-positive lymphocytes significantly increased in exposed young and adult rats compared to the respective controls. These results suggest that formaldehyde and/or xylene may affect the local immunity in BALT particularly in young and adult rats.
authors.affiliation: Faculty of Veterinary Medicine, Department of Histology and Embryology, Adnan Menderes University, Aydin, Turkey. sandikcimustafa@yahoo.com
authors.forename: M
authors.initials: M
authors.lastname: Sandikci
authors.forename: U
authors.initials: U
authors.lastname: Eren
authors.forename: S
authors.initials: S
authors.lastname: Kum
mesh_terms: D000367:Age Factors; D000818:Animals; D001980:Bronchi / Q000166:cytology / Q000187:drug effects* / Q000254:growth & development; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000187:drug effects*; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology / Q000187:drug effects*; D004202:Disinfectants / Q000633:toxicity*; D004357:Drug Synergism; D004622:Embryo, Mammalian; D005260:Female; D005557:Formaldehyde / Q000633:toxicity*; D018655:Lymphocyte Count; D008221:Lymphoid Tissue / Q000166:cytology / Q000187:drug effects* / Q000254:growth & development; D051381:Rats; D017207:Rats, Sprague-Dawley; D014992:Xylenes / Q000633:toxicity*
chemical_list: D004202:Disinfectants; D014992:Xylenes; D005557:Formaldehyde