Figure 4.
IL-18 treatment reduces early donor T cell expansion. Recipient mice were transplanted as in Fig. 2. (A) Splenocytes were harvested from the recipients at each time point as shown (n = 4/per group) and labeled with anti-CD3 PE and anti-CD45.1 FITC. The number of donor T cells (CD45.1+ CD3+) were determined (Allo + control, • vs. Allo + IL-18, ▪) at various time points, from days 2 to 5 post-BMT. *P = 0.03. Recipients of syngeneic BMT (○) demonstrated lower numbers of donor T cells at all time points. Data from one of three similar experiments is shown. (B) Nylon wool purified B6Ly5.2 donor T cells were labeled with CFSE as described in Materials and Methods and injected into B6D2F1 recipients after 1,300 cGy TBI. Splenocytes were harvested and pooled (n = 3/group) on day 3 post-BMT, and labeled with anti-CD45.1 APC. The percent of donor cells (CFSE+ CD45.1+) undergoing cell expansion was determined. Fewer percentage of donor cells underwent beyond two cell divisions in IL-18–treated group than allogeneic controls, 7 vs. 28%. One of three representative experiments is shown.