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Results demonstrate that post-translational modification of the N-terminus of the Sonic hedgegog sinaling protein by hydrophobic adducts, composed of long-chain fatty acid amides, leads to a 100-fold increases in the potency of the protein. Data indicate that the modifications do not alter protein's receptor affinity.

The biophysical/functional properties of wild-type human Sonic hedgehog (ShhN) have been compared with those of mutants in which some zinc-coordinating residues are mutated to alanine. Properties of the E176A mutant were not distinguishable from those of wild-type ShhN. The residue apparently does not contribute significantly to stabilization of the zinc-binding site. ShhN does not seem to require hydrolase activity for in vitro biological function.

The common gamma (gamma c)(super1) chain is a common component of receptors for the cytokines IL-2, IL-4, IL-9 and IL-15. The interactions of the extracellular parts of the IL-2RBeta and gamma c chains were characterized using gel filtration and SPR. It is found that binding of IL-2 to the intermediate affinity IL-2R on the surface of COS-7 cells is blocked by a mAb, CP.b8. The mechanism by which mAb CP.B8 inhibits complex formation is established.

An enzyme which has a basically wild-type characteristic is produced when Glu-37 in Escherichia coli is substituted with Ala in the aspartate transcarbamoylase. The thermal constancy of the enzyme exhibits minute attenuation. Catalysis and homotropic cooperativity do not require the reaction between Glu-37 and His-41, which affects the constancy of the C1-C2 interface minutely. The constancy of the interface is influenced by Asp-100. The catalytic trimer displays a fall in constancy, and the holoenzyme displays rising affinity for aspartate when Asn or Ala substitute Asp-100.

Investigates the mechanism of action of a murine monoclonal antibody, the CP.B8, specific for the extracellular of the human common y chain, which blocks the binding of interleukin (IL)-2 to the intermediate affinity IL-2R expressed on the cell surface. Literature of the study; Experimental procedures used to conduct the study; Findings; Discussions.

PEGylation of IFN-alpha has been used successfully to improve the pharmacokinetic properties and efficacy of the drug. To prepare a PEGylated form of human interferon-beta-1a (IFN-beta-1a) suitable for testing in vivo, we have synthesized 20 kDa mPEG-O-2-methylpropionaldehyde and used it to modify the N-terminal alpha-amino group of the cytokine. The PEGylated protein retained approximately 50% of the activity of the unmodified protein and had significantly improved pharmacokinetic properties following intravenous administration in rats. The clearance and volume of distribution at steady state were reduced approximately 30-fold and approximately 4-fold, respectively, resulting in a significant increase in systemic exposure as determined by the area under the curve. The elimination half-life of the PEGylated protein was approximately 13-fold greater than for the unmodified protein. The unmodified and PEGylated proteins were tested for their ability to inhibit the formation of radially oriented blood vessels entering the periphery of human SK-MEL-1 melanoma tumors in athymic nude homozygous (nu/nu) mice. In a single dose comparison study, administration of 1 x 10(6) units of unmodified IFN-beta-1a resulted in a 29% reduction in vessel number, while 1 x 10(6) units of PEGylated IFN-beta-1a resulted in a 58% reduction. Both treatments resulted in statistically significant reductions in mean vessel number as compared to the vehicle (control)-treated mice, with the PEGylated IFN-beta-1a-treated mice showing a statistically significantly greater reduction in mean vessel number as compared to the unmodified IFN-beta-1a-treated mice. In a multiple versus single dose comparison study, daily administration of 1 x 10(6) units of unmodified IFN-beta-1a for 9 days resulted in a 51% reduction in vessel number, while a single dose of 1 x 10(6) units of the PEGylated protein resulted in a 66% reduction. Both treatments resulted in statistically significant reductions in mean vessel number as compared to the vehicle-treated mice, with the PEGylated IFN-beta-1a-treated mice showing a statistically significantly greater reduction in mean vessel number as compared to the unmodified IFN-beta-1a-treated mice. Therefore, the improved pharmacokinetic properties of the modified protein translated into improved efficacy. Since unmodified IFN-beta is used for the treatment of multiple sclerosis and hepatitis C virus infection, a PEGylated form of the protein such as 20 kDa mPEG-O-2-methylpropionaldehyde-modified IFN-beta-1a may serve as a useful adjunct for the treatment of these diseases. In addition, the antiangiogenic effects of PEGylated IFN-beta-1a may be harnessed for the treatment of certain cancers, either as a sole agent or in combination with other antitumor drugs.