In contrast to the WT cagAE-Tg mice, the PR cagAE-Tg mice did not show gastrointestinal abnormalities, suggesting the requirement of tyrosine phosphorylation on EPIYA motifs for the in vivo pathogenicity of CagA protein in the gastrointestinal tract in mice.157 In addition, the WT cagAE-Tg mice showed leukocytosis associated with hypersensitivity to hematopoietic cytokines, including interleukin-3 (IL-3) and granulocyte-macrophage colony-stimulating factor (GM-CSF), in bone marrow cells. This evidence concerns the gene CSF2 and Increased total leukocyte count.