Cell proliferation studies were conducted using the protocol mentioned in Figure 2 and materials and methods. Briefly, naïve or in vivo primed CD4+ T cells were adoptively transferred into STAT6xRAG2-/- mice on day 0, followed by OVA/alum immunization of day 1. Mice were treated with BrdU i.p for 3 days. On day 5, splenocytes were harvested, single cell suspensions were prepared and total cell numbers were counted (column 1). Cells were stained with fluorochrome conjugated antibodies and analyzed by flow cytometry. Lymphocytes were gated based on forward and side scatter parameters. The CD4+ DO11.10+ population in each transfer group was gated based on double expression of CD4 and KJ126 by each cell (column 2). BrdU and CD44 expression in these gated cells was examined (columns 3 and 4 respectively). The numbers/percentages in columns 2-4 were determined by FACS Analysis. 20,000 events (splenocytes) were collected for each tube/analyte.