Interferon tau, Recombinant, Ovine (IFNt)
|Molecular Biology||Storage: -20°CShipping: Blue Ice|
Interferon-tau is also known as TP-1 (trophoblast protein-1) 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. Interferon-tau has potent immunosuppressive and antiviral activities similar to other type I IFN but is less cytotoxic than IFN-alpha and IFN-beta. The current investigation concerns the effect of recombinant ovine IFN- tau (Recombinant Ovine IFN- tau) 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 upregulated the expression of MHC class I on CVE. One proposed action by which type I IFN reduces the relapse rate in MS is via interference with IFN-g-induced MHC class II expression. Interferon tau was shown to downregulate IFN-gamma-induced MHC class II expression on CVE and, hence, may be of potential therapeutic value in downregulating inflammation in the central nervous system (CNS). Interferon- tau did not upregulate the expression of MHC class II on CVE. Interferon- tau also inhibited the replication of Theiler's virus in CVE.
Recombinant Ovine Interferon-Tau produced in E.Coli is a single, non-glycosylated, polypeptide chain containing 172 amino acids and having a molecular mass of ~20kD. Recombinant Ovine IFN-Tau is purified by proprietary chromatographic techniques.
The sequence of the first five N-terminal amino acids was determined and was found to be Cys-Tyr-Leu-Ser-Arg.
Dimers and Aggregates:
Less than 1% as determined by silver-stained SDS-PAGE gel analysis.
Ovine IFN-Tau is fully biologically active when compared to standard. The specific activity as determined in a viral resistance assay using bovine kidney MDBK cells was found to be 5.7 x 107 IU/mg.
0.1ng/ug (IEU/ug) of Recombinant Ovine Interferon-Tau.
Protein quantitation was carried out by two independent methods:
1. UV spectroscopy at 280 nm using the absorbency value of 1.027 as the extinction coefficient for a 0.1% (1mg/ml) solution. This value is calculated by the PC GENE computer analysis program of protein sequences (IntelliGenetics).
2. Analysis by RP-HPLC, using a calibrated solution of Recombinant Ovine IFN-Tau as a Reference Standard.
It is recommended to reconstitute the lyophilized interferon-Tau in sterile 18M -cm H2O not less than 100µg/ml, which can then be further diluted to other aqueous solutions.
Lyophilized Recombinant Ovine Tau Interferon although stable at room temperature for 3 weeks, should be stored desiccated below -180C. Upon reconstitution IFN-Tau should be stored at 40C between 2-7 days and for future use below -180C. For long term storage it is recommended to add a carrier protein (0.1% HSA or BSA). Please avoid freeze-thaw cycles.
Source: E. coli
Purity: 95% as determined by RP-HPLC, anion-exchange FPLC and/or reducing and non-reducing SDS-PAGE Silver Stained gel.
Form: Supplied as a lyophilized powder in 0.5X PBS, pH 7.4.
Important Note: This product as supplied is intended for research use only, not for use in human, therapeutic or diagnostic applications without the expressed written authorization of United States Biological.