(A) Proliferation, as measured by Ki67 expression among B6 ^CD45.1+ CD8⁺ T cells activated with BALB/c allogenic splenocytes, with or without the addition of E1 or E0 eosinophils. Data represent 1 of 2 experiments with 4 separate replicates per experiment. (B) In vitro differentiation, as measured by CD44 and CD62L expression on B6^CD45.1+ CD8⁺ T cells stimulated by BALB/c allogenic splenocytes, with or without the addition of E1 or E0 eosinophils. (C) iNOS expression in CD8⁺ T cells activated with BALB/c allogenic splenocytes, with or without the addition of IFN-γ– and TNF-α–blocking antibodies (representative experiment of 4 separate MLRs). (D) Modulation of CD8⁺ T cell proliferation by E0 and E1 eosinophils in MLR of BALB/c allogenic splenocyte stimulators with IFN-γ and TNF-α blockade. (E) Schematic representation of the regulatory feedback loop between alloreactive lymphocytes and eosinophils in lung grafts. ns, P > 0.05; **P < 0.01. Comparison by Friedman’s test was used for paired data, while the Kruskal-Wallis test was used for the unpaired group of observations. Post-hoc analysis of differences and comparison of differences between pairs of data were performed with the Wilcoxon rank test and the Mann-Whitney U test for paired and unpaired observations, respectively. For the box plot, the bottom and top of the boxes represent the lower and upper quartiles, respectively; the dark band inside the box represents the median; and the top and bottom whiskers represent the maximum and minimum observed values, respectively.