Preparation and investigation of core-shell nanoparticles containing human interferon-α.

Sustained release of active interferon-α (IFN-α) has been achieved from core-shell nanoparticles (NPs) prepared by aqueous precipitation of IFN-α-enriched human serum albumin (HSA-IFN-α) and layer-by-layer (L-b-L) by coating of the IFN-α NPs with poly(sodium-4-styrene) sulphonate (PSS) and chitosan (Chit). The concentration and the pH of HSA solution were optimized during the development of this method. Dynamic light scattering (DLS), zeta-potential, thermal analysis (differential scanning calorimetry (DSC) and termogravimetry (TG)), X-ray diffraction (XRD), IFN-α activity and morphology (transmission electron microscope (TEM)) studies were used to control the preparation and analyse the products.

Isolation and functional characterization of a cyst(e)amine-sensitive protein protecting methyl-dithio groups.

We have previously shown that S-methylthio cysteine mixed disulfide and cystamine potently stimulate thiol production and glutathione synthesis of a human T-cell line in SH-poor medium. Here, we describe a simple photometric method for the determination of methylthio-mixed disulfides (MT-groups) and show that liver contains relatively large amount of MT-groups mainly associated with the globulin fractions. At least a part of methylthio (MT-) globulins is in a complex with a heat-stable protein protecting methylthio-groups against reduction and was designated as anti-methylthio factor (AMTF).