One week after infection (end of Week 1), the number of circulating CD4+ and CD8+ T cells remained unaffected by the immunosuppressant treatments (Fig 2); values for both fell within the range for naive mice of the same age (CD4+ T cells 1124±238 cells/mm3, CD8+ T 716±173 cells/mm3; determined in-house). This evidence concerns the gene CD8A and infection.