BTLA expression on OT1 cells is not required for their accumulation after LM-OVA infection.

Purified naïve WT or Btla−/− OT1 cells were adoptively transferred into CD45.1+ recipient mice and one day post transfer, mice were orally infected with LM-OVA as indicated in Material and Methods. A- The percentage (top panel) and absolute number (bottom panel) of donor WT and Btla−/− OT1 cells in the peripheral blood of infected mice was tracked at different time points after infection. OT1 cell numbers in the peripheral blood were calculated as numbers of OT1 cells per 3×104 peripheral blood lymphocytes (PBL). Data shown correspond to the average of 6–8 mice per group. B- Percentages of CD45.2+ WT and Btla−/− OT1 cells in the spleen, MLN and IEL of infected mice, 7 days p.i. Each symbol represents an individual mouse from a total of 7–9 mice per group, pooled from two independent experiments. C- Absolute number of WT (open bars) and Btla−/− (filled bars) OT1 cells in the spleen and MLN of infected animals at 7 days p.i. Data shown correspond to the average of the number of animal indicated in B. D- Percentage of OT1 memory cells in the spleen and IEL of WT (open bars) and Btla−/− (filled bars) mice, 70 days p.i. Absolute number of OT1 cells in the spleen of these animals is also represented. Differences between percentage and absolute numbers of WT and Btla−/− OT1 are not statistically significant. Data shown was pooled from two independent experiments with total of 7–9 mice per group, and E, F- Co-transfer experiment with 5×104 CD45.1+CD45.2+ WT and CD45.2+ Btla−/− naïve OT1 cells transferred into CD45.1+ recipient mice that were subsequently infected with LM-OVA. Data shown correspond to the percentage of WT (circles) and Btla−/− (squares) cells within the total OT1 cells found in the spleen and IEL of infected mice, 7 days (E) and 70 days (F) p.i. Each symbol represents an individual mouse from a total of 9 mice per group, pooled from two independent experiments.