T1- and T2-mediated GVT effects. (A) Lung histology. T1 and T2 recipient lungs were harvested at day 28 after BMT, and the degree of tumor infiltration was compared with that of BMT and TSA tumor control mice. Tumor was scored on a scale of 0 to 4 (n = 3 per treatment group), with the mean ± SEM shown. (B) Pulmonary tumor infiltrate. A single-cell suspension of lung tissue was isolated at day 14 after BMT and evaluated for the presence of TSA tumor cells, defined by their flow cytometric expression of H-2K^d and absence of H-2K^b (n = 3 recipients per BMT group, with mean ± SEM shown). (C) Pulmonary T1 and T2 infiltrates. A pulmonary single-cell suspension was obtained on days 5 and 14 after BMT. The T1 and T2 populations were generated from Ly5.1 B6 congenic mice and evaluated by flow cytometry using the CD45.1 marker. Values are shown as mean ± SEM (n = 3).