Adoptive transfer of acute lung injury

In this study, we describe a novel adoptive transfer protocol to study acut e lung injury in the rat. We show that bronchoalveolar lavage (BAL) cells i solated from rats 5 h after intratracheal administration of lipopolysacchar ide (LPS) induce a lung injury when transferred to normal control recipient rats. This lung injury is characterized by increased alveolar-arterial oxy gen difference and extravasation of Evans blue dye (EBD) into lungs of reci pient rats. Recipient rats receiving similar numbers of donor cells isolate d from healthy rats do not show adverse changes in the alveolar-arterial ox ygen difference or in extravasation of EBD. The adoptive transfer-induced l ung injury is associated with increased numbers of neutrophils in the BAL, the levels of which are similar to the numbers observed in BAL cells isolat ed from rats treated for 5 h with LPS. As an indicator of BAL cell activati on, donor BAL cell inducible nitric oxide synthase (iNOS) expression was co mpared with BAL cell iNOS expression 48 h after adoptive transfer. BAL cell s isolated 5 h after LPS administration expressed iNOS immediately after is olation. In contrast, BAL cells isolated 48 h after adoptive transfer did n ot express iNOS immediately after isolation but expressed iNOS following a 24-h ex vivo culture. These findings indicate that the activation state of donor BAL cells differs from BAL cells isolated 48 h after adoptive transfe r, suggesting that donor BAL cells may stimulate migration of new inflammat ory cells into the recipient rats lungs.