title: A model of pulmonary granulomata induced by beryllium sulfate in the rat.
abstract: In humans beryllium is known to cause pulmonary granulomata which are histologically indistinguishable from sarcoidosis. There is some evidence in man that beryllium-induced pulmonary granulomata are immunologically mediated. We set out to develop an animal model to study the immunopathogenesis of beryllium-induced granulomatous lung disease. Beryllium sulfate (BeSO4) was injected intratracheally (i.t.) into F344 rats previously immunized to BeSO4. This results in well-formed, sarcoid-like lung granulomata at 6 weeks post BeSO4. There was a conspicuous presence at 4 weeks post BeSO4 of numerous, perivascularly located Langhans' giant cells which preceded the development of well-formed granulomas at 6 weeks. Rats were sacrificed at 4, 6, 8 and 12 weeks after i.t. BeSO4. At the time of sacrifice bronchoalveolar lavage (BAL) was performed; B and T (W3/25+ helper 0X8+ suppressor/cytotoxic) lymphocyte populations were quantitated and compared to lymphocyte populations obtained from lung tissue. Both B and T cells were significantly elevated in lung tissue post BeSO4. At 4 weeks when granulomata were just developing, a W3/25+ to 0X8+ ratio of 20:1 in lavage and 2:1 in lung tissue was seen. At 6 weeks when granulomata were well-formed there was a predominance of W3/25+ cells in lavage but not in lung tissue. At 8 and 12 weeks, when the granulomata were regressing, lavage fluid still contained a W3/25+ predominance in contrast to lung tissue which contained a predominance of 0X8+ cells.(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000818:Animals; D001607:Berylliosis / Q000473:pathology; D001608:Beryllium / Q000633:toxicity*; D004195:Disease Models, Animal; D006099:Granuloma / Q000139:chemically induced* / Q000473:pathology; D007114:Immunization / Q000379:methods; D008168:Lung / Q000473:pathology; D008171:Lung Diseases / Q000139:chemically induced* / Q000473:pathology; D008214:Lymphocytes / Q000473:pathology; D008297:Male; D051381:Rats; D011916:Rats, Inbred F344; D013047:Specific Pathogen-Free Organisms; D007507:Therapeutic Irrigation
chemical_list: C020711:beryllium sulfate; D001608:Beryllium