IFN-τ is a new class of type I IFN that is secreted by the trophoblast and is the signal for maternal recognition of pregnancy in sheep. IFN-τ has potent immunosuppressive and antiviral activities similar to other type I IFN but is less cytotoxic than IFN-alpha/β. The current investigation concerns the effect of recombinant ovine IFN-tau (rOvIFN-τ) on the modulation of MHC class I and II expression on cloned mouse cerebrovascular endothelial (CVE) cells. IFN-tau induced tyrosine phosphorylation of Stat1 and up regulated the expression of MHC class I on CVE. One proposed action by which type I IFN reduce the relapse rate in MS is via interference with IFN-gamma-induced MHC class II expression. IFN-τwas shown to down regulate IFN-gamma-induced MHC class II expression on CVE and, hence, may be of potential therapeutic value in down regulating inflammation in the central nervous system (CNS). IFN-τdid not upregulate the expression of MHC class II on CVE. IFN-τalso inhibited the replication of Theiler’s virus in CVE.
Source
Yeast
Molecular Weight
Approximately 19.9 kDa, a single glycosylated polypeptide chain containing 172 amino acids.
Biological Activity
Fully biologically active when compared to IFN-alpha. The specific activity determined by a viral resistance assay is no less than 1.0 × 107 IU/mg.
Appearance
Sterile filtered white lyophilized (freeze-dried) powder.
Formulation
Lyophilized from a 0.2 um filtered concentrated solution in PBS, pH 7.4.
Endotoxin
Less than 0.1 EU/ug of rOvIFN-τ as determined by LAL method.
Reconstitution
We recommend that this vial be briefly centrifuged prior to opening to bring the contents to the bottom. Reconstitute in sterile distilled water or aqueous buffer containing 0.1 % BSA to a concentration of 0.1-1.0 mg/mL. Stock solutions should be apportioned into working aliquots and stored at ≤ -20°C. Further dilutions should be made in appropriate buffered solutions.
Stability and Storage
Use a manual defrost freezer and avoid repeated freeze-thaw cycles.- 12 months from date of receipt, -20 to -70 °C as supplied.- 1 month, 2 to 8 °C under sterile conditions after reconstitution.- 3 months, -20 to -70 °C under sterile conditions after reconstitution.
