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Beryllium Stimulates a Local Angiotensin System in Chronic Beryllium Disease. T Hendry-Hofer* AP Fontenot¶, EA Barker*, M Boguniewicz*, LS Newman* and LA Maier. Background. Angiotensin Converting Enzyme (ACE) implicated in the immune response in granulomatous disease
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Beryllium Stimulates a Local Angiotensin System in Chronic Beryllium Disease T Hendry-Hofer* AP Fontenot¶, EA Barker*, M Boguniewicz*, LS Newman* and LA Maier
Background • Angiotensin Converting Enzyme (ACE) implicated in the immune response in granulomatous disease • Present on monocytes, macrophages, T cells • Reflects granulomatous burden • ACE inhibitor treatment of mice with S. mansoni decreases granulomatous response • ATII is produced from ATI, by ACE • Acts on two receptors, AT1 and AT2 • Proliferation of fibroblasts, production of collagen • Stimulates a number of growth factors • Block AT1 receptor, reduce fibrosis
Background (cont.) • Serum ACE levels are associated with disease severity in CBD • Does not discriminate CBD from BeS or Be Exposed • Serum ACE activity correlated with granulomatous inflammation (Newman LS, et al. Am Rev Respir Dis. 1992; 146: 39-42) • ACE polymorphism has been associated with increased serum ACE in CBD • 287 bp insertion (I) or deletion (D) at intron 16 • Highest serum ACE activity in CBD subjects with DD genotype (Maier LA, et al. Am J Respir Crit Care Med. 1999; 159: 1342-1350)
Hypothesis ACE and ATII will be stimulated in the skin and BAL fluid of individuals with CBD during granuloma formation
Methods • Study Subjects: • CBD was defined by: • A positive blood and or BAL lymphocyte proliferation test or positive skin patch test and • The presence of non-caseating granulomas on biopsy • ________________________________________________ • Sarcoidosis was defined by: (ATS, Statement on Sarcoidosis,1999) • A compatible case history and chest x-ray • The presence of non-caseating granulomas • Negative BAL stains and culture for acid fast bacteria, fungi or parasites • No history of beryllium exposure
Beryllium Skin Patch Testing and Immunohistochemistry • Patch Testing – Aqueous solution of 1% BeSO4 for 48 hours • – Punch biopsies at 0, 2, 3, 4, 14 and 35 days • Unstimulated CBD lavage cells were attached to slides by cytospin followed by methanol fixation • Immunohistochemistry was used to localize: CD3, CD4, CD8, CD68, ACE and ATII • Morphometric analysis used for quantification
ACE and ATII Protein • Bronchoscopy: BAL cells were obtained by routine lavage from 20 CBD and 5 sarcoidosis cases • BAL Cell culture:. Cells were cultured at 1 x 106 cells/ml in the presence and absence of 10-4 M BeSO4 • Protein Analysis: • ATII was measured by RIA • ACE was measured by ELISA
Summary • ACE colocalized with CD4+ T cells • ATII colocalized with CD68+ macrophages • Be stimulates: – ACE and ATII in skin patch granulomas – increased ACE production by CBD BAL cells • Be does not stimulate: – ACE production by sarcoidosis BAL cells – ATII production by CBD or Sarcoidosis BAL Cells
Conclusions • During beryllium stimulated granuloma formation • ACE is produced by CD4+ T cells • ATII by CD 68+ macrophages • Beryllium stimulates ACE production in the skin and lung of individuals with CBD • A local angiotensin system is stimulated by Be during granuloma formation in CBD subjects
May Gillespie Eric Wilcox Richard Sawyer Karen Dockstader Lynn Jui Michele Bausch This grant was funded by: NIH K08 HL-03887 NIH R01ES06538 NIH M01 RR-00051 Acknowledgments