Thus, the lower intensity of cerebral lesions observed in Ext-Ts-treated PbA-infected mice in our investigation was related to the lower IFN-γ and consequently lower ICAM-1 and VCAM-1 expression in the organ as well as the decrease of chemokine receptor CCR5 involved in leukocyte trafficking. This evidence concerns the gene CCR5 and Abnormal cerebral morphology.