Naïve 3xTg-AD mice have been previously shown to have abnormal enlargement of the spleen and liver, an increased number of double-negative CD4−CD8− splenocytes [20], increased lymphocyte chemotaxis [21] and increased C-C chemokine receptor 6 (CCR6) expression outside of the CNS [22]. The gene discussed is CCR6; the disease is Alzheimer disease.