Experimental hypersensitivity pneumonitis: influence of donor sensitization

Experimental hypersensitivity pneumonitis (EHP) can be transferred to strain 2 guinea pigs by lymphoblasts from lymph node cells from sensitized guinea pigs cultured in vitro with antigen. We sought to examine the relationship between characteristics of the donor animal and development of competence to transfer EHP. We also compared cell populations that were capable and incapable of transfer using flow cytometry and fluorescein conjugated anti-Ig to determine cell size and surface IgG + (SIg +: surface immunoglobulin-positive) cells. Lymph node cells from donor animals were cultured with a soluble extract of Micropolyspora faeni (10 micrograms/ml) for 72 hours; blasts were then isolated and transferred intravenously to syngeneic recipients. Control recipients received an equal volume of medium. Four groups of donors were used: animals systemically sensitized with Freund's adjuvant and M. faeni and challenged with two, four, or eight weekly intratracheal injections of M. faeni (2-, 4-, and 8-week group); and animals sensitized with Freund's adjuvant and normal saline and challenged with two weekly intratracheal injections of normal saline (NS group). Recipients were challenged intratracheally with M. faeni 48 hours after the cell transfer and killed 4 days thereafter. Randomly selected microscopic fields of the lung (250/animal) were judged to be normal or abnormal without knowledge of treatment. All animals were maintained in high efficiency particulate accumulator-filtered air. There was a low level of pulmonary response to an intratracheal challenge of M. faeni in animals that received media.(ABSTRACT TRUNCATED AT 250 WORDS)