CORYNEBACTERIUM PARVUM-INDUCED AND MYCOBACTERIUM-BOVIS BACILLUS CALMETTE-GUERIN-INDUCED GRANULOMA-FORMATION IS INHIBITED IN TNF RECEPTOR I (TNF-RI) KNOCKOUT MICE AND BY TREATMENT WITH SOLUBLE TNF-RI

The aim of this study was to examine the role of TNF receptor I (TNF-R I) in the pathogenesis of beat-killed Corynebacterium parvum- and live bacillus Calmette-Guerin (BCG)-induced granulomas, Granuloma formatio n was analysed in TNF-RI knockout mice and after treatment with solubl e TNF-RI (sTNF-RI). TNF-RI knockout mice injected with C. parvum or EC G developed fewer and smaller granulomas than wild-type control mice. Mice treated with sTNF-RI from days 7 to 13 after injection of C. parv um or BCG developed fewer and smaller granulomas than saline-treated c ontrol mice, Established granulomas regressed in rats treated with sTN F-RI from days 1O to 13 after injection of C. parvum. In conclusion, T NF signaling via TNF-RI contributes to the pathogenesis of C. parvum- and BCG-induced granulomas. sTNF-RI inhibits the development of granul omas and can cause the regression of established granulomas.