CD3+ and CD4+ cells adoptively transfer experimental hypersensitivity pneumonitis.

To characterize the cells responsible for transfer of adoptive murine experimental hypersensitivity pneumonitis (EHP), we depleted Micropolyspora faeni (M. faeni)-sensitized C3H/HeJ spleen cell (SC) cultures of CD3+, CD4+, or CD8+ cells before administration to recipients. We determined the length of time sensitization persists, the ability of cultured lung-associated lymph node (LALN) cells to transfer EHP, and the ability of cultured SC from animals subjected to two, four, or eight weekly intratracheal challenges of M. faeni to transfer EHP. The extent of pulmonary inflammatory response after challenge with intratracheal M. faeni was used to determine adoptive transfer. Depletion reduced the proportion of CD3+ cells from 21 to 1%, CD4+ cells from 15 to 3%, and CD8+ cells from 7 to 1% in the cultured SC population. The proportion of B cells exhibited reciprocal changes. Cultured SC could transfer EHP. Depletion of CD3+ and CD4+, but not CD8+ cells, ablated or diminished the capacity to transfer EHP. Sensitized cells persisted in recipients for at least 8 wk. Cultured LALN cells could transfer EHP. Recipients of cultured SC from 4- and 8-wk donors exhibited less extensive pulmonary abnormalities than recipients of cultured SC from 2-wk donors. The proportion of CD3+, CD4+, CD8+, B cells, and macrophages was the same in cultured cells from 2-, 4-, and 8-wk donors. We conclude that the active cells in SC cultures are CD3+, CD4+, and CD8- T cells, and there are differences in the ability of cultured cells to adoptively transfer EHP that are dependent on the nature of the donor but not on the phenotype of the cell population.