However, the level of virus in the serum and organs was not further decreased. Affinity analysis indicated that the CTLs in uninfected peptide-inoculated controls had high affinity for LCMV nucleoprotein, whereas the CTLs in persistently infected mice had low affinity for the protein. These data indicate that in mice persistently infected with virus in utero or at birth, complete tolerance does not occur and antiviral CTLs can be generated. However, the CTLs are of low affinity, and manipulation is required to increase the affinity to allow an opportunity for effector CTLs to clear the persistent infection. Clearance of persistent LCMV can be accomplished by using immunocytotherapy.
Death is associated with profound immunosuppression.
In addition, encephalomyelitis develops in roughly 1 in 1000 persons with measles virus infection and a chronic CNS disease termed subacute sclerosing panencephalitis in about 1 in 100,000 to 1 in 1 million. Marked T-cell infiltration, especially CD4 T cells, occurs. In collaboration with M. Billeter, University of Zurich, Switzerland, we used reverse genetics to manipulate specific measles virus genes. I molecules on endothelial cells. Lymphocytic infiltration, chemokine upregulation, and viral load were equivalent in both groups of mice.