Differential role for T cells in the development of fibrotic lesions associated with XXXX /L-induced @entity3616 versus @entity649 .

@entity5131 @entity82 @entity66 @entity548 @entity19 @entity649 @entity4 @entity16 @entity3616 @entity5765 @entity5924 @entity358 @entity379
@entity3616 ( @entity3616 ) and @entity649 ( @entity649 ) are two @entity358 with fibrotic components. @entity3616 is characterized by perivascular/peribronchiolar leukocyte infiltration leading to the development of @entity82 . @entity649 is a @entity66 that includes an acute phase, consisting of severe leukocyte infiltration, @entity4 , @entity548 , and the formation of hyaline membranes, and a chronic phase, which is characterized by persistent intra-alveolar and interstitial @entity82 . CBA/J @entity19 infected with 1 x 10(6) plaque-forming units (pfu) @entity5765 /L develop follicular @entity5924 and @entity82 similar to @entity3616 . In contrast, CBA/J @entity19 infected with 1 x 10(7) pfu @entity5765 /L develop histologic characteristics of @entity649 including @entity16 , hyaline membranes, and @entity82 . In this report, we demonstrate a differential role for T lymphocytes in the development of @entity82 associated with @entity3616 versus @entity649 . Neonatally thymectomized CBA/J @entity19 infected with 1 x 10(7) pfu ( @entity649 ) @entity5765 /L still develop the hallmark characteristics of @entity649 , including a severe @entity5131 with cellular infiltrates comprised mainly of macrophages and neutrophils, hyaline membrane formation, and @entity548 during the acute phase of the disease and persistent @entity82 during the chronic phase of the disease. In contrast, neonatally thymectomized CBA/J @entity19 infected with 1 x 10(6) pfu ( @entity3616 ) @entity5765 /L do not develop @entity82 associated with @entity3616 . Therefore, while T cells are necessary for the development of intraluminal @entity82 associated with @entity3616 , they are not necessary for the development of intraluminal @entity82 associated with @entity649 . Furthermore, we suggest that @entity379 plays a key role in the fibrotic process and that elevated levels of @entity379 are associated with a continuum from least to more severe @entity82 .
