Chemistry: natural resins or derivatives; peptides or proteins; – Peptides of 3 to 100 amino acid residues – 15 to 23 amino acid residues in defined sequence
Patent
1992-06-18
1994-12-20
Lee, Lester L.
Chemistry: natural resins or derivatives; peptides or proteins;
Peptides of 3 to 100 amino acid residues
15 to 23 amino acid residues in defined sequence
530324, 530325, A61K 3702, C07K 710
Patent
active
053747135
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to peptide inhibitors of phospholipase A.sub.2 purified from inflammatory sites.
BACKGROUND ART
Phospholipase A.sub.2 is an enzyme which hydrolyzes .beta.-ester bonds in phospholipid to give fatty acids and lysophospho-lipids. Especially, it releases arachidonic acid which can be a precursor of prostaglandins, leukotriene, thromboxane and the like from membrane phospholipids and is thought to play an important role in the production of these inflammatory mediators. In recent years, phospholipase A.sub.2 has been purified from the inflammatory sites of human inflammatory diseases and inflammatory model animals (it will be called phospholipase A.sub.2 from inflammatory sites) and its properties have been clarified. This enzyme is thought to have the action to accelerate the inflammatory reactions, therefore the drug to inhibit the activity of this enzyme can be expected to reveal anti-inflammatory actions.
Complement C3 is a protein which has been known to perform the key functions in the complement pathway. C3 is hydrolyzed stepwise by a protease in blood. In other words, it is cleaved first with convertase into C3a an dC3b. C3b binds through its thiol ester site to the surface of activators followed by activation of the complement pathway to form a membrane attack complex. C3a works as an anaphylatoxin. At this time, a minor part of C3b binds to the activators, while the major part reacts with water to lose the binding activity, further undergoes hydrolysis by a protease to convert into C3dg or C3d finally.
The present inventors have already applied for patents after finding that human and rat C3dg inhibit specifically phospholipase A.sub.2 purified from inflammation sites, succeeding in expression of rat C3 cDNA in Escherichia coli to produce a part of rat C3.alpha. chain (containing the C3dg part) as a recombinant protein, and realizing that the recombinant protein inhibits specifically phospholipase A.sub.2 purified from inflammatory sites (PCT/J90/00996, W091/01999).
Human C3dg is, however, a protein of about 39 kDa molecular weight and it can be anticipated that the use of said protein as an anti-inflammatory as such will cause troubles in, for example, the transference to the affected part, the storage stability or antigenicity.
Thus, a novel peptide having inhibitory activity against phospholipase A.sub.2 from inflammatory sites is desirably provided as an anti-inflammatory without such troubles.
Hereupon, the present inventors have made intensified studies in order to solve the above-mentioned problems to find that a part of the amino acid sequence of C3dg has action to inhibit phospholipase A.sub.2, and attained the present invention.
DISCLOSURE OF THE INVENTION
In other words, the present invention is a peptide inhibitor of phospholipase A.sub.2 purified from inflammatory sites having an amino acid sequence shown in SEQ ID No: 1.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 gives the fractionation of the peptide in Example 1 according to the present invention by means of reversed phase HPLC.
FIG. 2 gives the inhibitory activity of the peptide according to the present invention against phospholipase A.sub.2, which was determined in Example 2.
In these figures, -- show the cases where the phospholipase A.sub.2 purified from human inflammatory sites, .largecircle.--.largecircle.give the phospholipase A.sub.2 from rat inflammatory sites and x--x show the phospholipase A.sub.2 from procine pancreas.
BEST EMBODIMENT OF THE INVENTION
The peptides include the amino acid sequence of 21 residues shown in the SEQ ID No: 1. The amino acid sequence of said peptide is identical with the amino acid sequence from No. 612 to the C-terminus of human C3.alpha. chain. In the amino acid sequence in sequence No. 1, the peptides having substitution, deletion or insertion of one or more amino acid residues are also included in the peptides according to the present invention as long as they have the inhibitory activity against phospholipase A.sub.2 from inflammatory
REFERENCES:
International Search Report, Dec. 12, 1991.
Hellman et al, "Amino Acid Sequence of the Trypsin-generated C3d Frgment from Human Complement Factor C3", Biochem. J. vol. 230, No. 2 (1985).
deBruijn et al., "Human Complement Component C3: cDNA Coding Sequence and Derived Primary Structure", Proc. Natl. Acad. Sci. U.S.A., vol. 82, No. 3 (1985).
Hellman et al, Biochem. J. 230, pp. 353-361 (1985).
Suwa et al, PNAS 87, 2395-2399 (1990).
Azuma Chieko
Imaizumi Atsushi
Inoue Keizo
Kudo Ichiro
Okada Masahiro
Lee Lester L.
Teijin Limited
LandOfFree
Peptide inhibitors of phospholipase A.sub.2 purified from inflam does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Peptide inhibitors of phospholipase A.sub.2 purified from inflam, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Peptide inhibitors of phospholipase A.sub.2 purified from inflam will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2386723