WO1991015216A1

WO1991015216A1 - Method and medicament for prevention or medication of human leucocyte elastase-mediated pulmonary diseases

Info

Publication number: WO1991015216A1
Application number: PCT/US1991/002299
Authority: WO
Inventors: Thomas P. Kennedy; John R. Hoidal
Original assignee: Kennedy Thomas P; Hoidal John R
Priority date: 1990-04-05
Filing date: 1991-04-02
Publication date: 1991-10-17
Also published as: AU7681091A

Abstract

A medicament and method for treatment of human leucocyte-mediated diseases comprising the administration of a polysulfated polysaccharide to the host.

Description

ETHOD AND MEDICAMENT FOR PREVENTION OR

MEDICATION OF HUMAN LEUCOCYTE ELASTASE-

MEDIATED PULMONARY DISEASES

This invention was made with government support under Contract No. 5 ROl HL 37615 awarded by the National Institutes of Health. The government has certain rights in this invention. This invention relates to methods and pharmaceuti¬ cally effective compounds useful in the prevention or media¬ tion of human leucocyte elastase- ediated pulmonary dis¬ eases.

Human leucocyte elastase (HLE) (3.4.21.11) is a serine proteinase stored in the azurophil granules of poly- morphonuclear leucocytes. HLE is capable of hydrolyzing most connective tissue components, especially elastin. Destruction of elastin and the concomitant loss of elastic recoil in the lung parenchyma has been postulated as arising from an imbalance between elastase and its primary inhibi¬ tor, alpha-1-protease. The source of such possible imbal¬ ance is not known. The presumed role of elastase is tc degrade bacterial cell wall components within the confines of the phagoso e once the neutrophil has ingested a microbe. Unfortunately, elastase is often released inadvertently into the nearby extracellular milieu during the process of neu¬ trophil activation and microbial phagocytosis. To prevent injury by free elastase, alpha-1-protease binds to free elastase and inactivates it. it has been suggested in the prior art that var¬ ious pulmonary diseases are elastase-mediated. Emphysema, cystic fibroεiε, acute respiratory distress syndrome, bron¬ chial pneumonia, and other similar diseases are reported tc be associated with excessive proteolysis, especially, elaε- tolysis.

HLE exhibits rather unusual features when compared with other serine proteases such as typsin, chymotrypsin and porcine pancreatic elastase. In the prior art, researchers have commonly used the more readily available chymotrypsin or porcine pancreatic elastase in studying the mechanism of catalysis of the serine family of proteases and their inter¬ action with inhibitors. This has led to less than defini- tive conclusions, such as, for example, reported equivalent degradation of purified elastin by HLE and porcine pancreat¬ ic elastase, but with HLE exhibiting a preferential decrease ^■ in degradation of elastin contained in an extracellular matrix. Several inhibitors, of a wide variety, have been developed for serine proteases, including irreversible inhibitors which are further classified as affinity-label inhibitors and mechanism-based inhibitors; and reversible inhibitors which are further classified as tight-binding, slow binding, slow tight-binding and classical. Affinity- label inhibitors have been tested with HLE but their high reactivity makes their use problematical. Mechanism-based inhibitors include haloenal lactones, chloropyrones, isocou- marins, and ynenol lactones. No in vivo studies are known to be reported for these compounds and their potential as therapeutic agents remains unknown. Whether one uses the affinity-labels or mechanism-based inhibitors, the goal is to achieve irreversible or at least long-term inhibition of the enzyme. This is precisely the mechanism for inhibition of elastase by alpha-1-protease inhibitor. This latter inhibitor, however, suffers from its susceptibility to oxidation which renders it ineffective as an elastase inhib¬ itor. Thus, alpha-1-protease is rendered ineffective in the pulmonary tract by reason of the oxygen metabolites (H₂0₂) , oxygen-derived free radicals (super oxide anion, hydroxyl radical) , spin-altered states of oxygen (singlet oxygen) , hypochlorous acid or oxidants associated with smoke inhala¬ tion (cigarette smoke) .

Reversible inhibitors form a stable enzyme-inhibi- tor complex. Examples include peptide keto esters and peptide boronic acids. Whereas peptidyl boronic acid com¬ pounds have been found effective, in vitro, they are rapidly reversible and actually enhance HLE-induced emphysema in animal models.

Polysulfated polysaccharides, such as Arteparon (a sulfated glysosaminoglycan derivative of chrondroitin sul- fate) , Structum (a polydisperse mixture of chrondroitin-4- sulfate and chrondroitin-6-sulfate, and disodium salt ex¬ tracted from the cartilage of bovine trachea) , and other compounds have been suggested as inhibitors of elastase in vitro (as the term is used in a general sense) . However, Arteparon has been implicated in deaths from cerebral hemor¬ rhage, thus rendering this compound and its parent, chron¬ droitin sulfate, seriously suspect for in vivo use. In similar manner, heparin has a small, but unfortunately serious risk of immune-mediated arterial thrombosis associ- ated with its use so that this compound if useful for "in- hospital" therapy where its potential side effects may be carefully monitored, and therefore is not indicated as a practical outpatient pharmaceutical for elastase inhibition. Moreover, the prior art teaches that the effectiveness of polysulfated polysaccharides, such as chrondroitin sulfate (including Arteparon) , heparin, and sulfated dextrans and chitosans are ineffective as elastase inhibitors at the lower molecular weight fractions of these compounds. The degree of sulfation of the compound is reported to strongly affect the inhibition efficacy of the compounds. For exam¬ ple, it has been reported that polysulfated dextrans having a molecular weight below about 100,000 Daltons are relative¬ ly ineffective as an elastase inhibitor when the degree of sulfation is less than about 1. Contrary to the relatively voluminous teachings of the prior art that certain sulfated polysaccharides can serve as inhibitors of elastase in vitro, to the knowledge of the present inventors, there has been no successful development of an effective medicament for pulmonary tract- associated diseases that are mediated by HLE.

The problems associated with the prior art com¬ pounds and or techniques of administration of such compounds include such matters as noted hereinabove relating ro the toxicity or undesirable side effects of certain polysulfated polysaccharides, ineffectiveness in the presence of oxi- dants, requirement that the compound be of relatively large molecular weight which complicates its delivery to sites within the pulmonary tract and which may contribute to its toxicity or the development of side effects. Other consid¬ erations when examining the inhibition of elastase in the pulmonary tract include solubility of the compound ^• in aque- ous media, electrolytic make-up of the compound (elastase is strongly cationic) , physiological half-life, dispersibility in vivo, ability to target elastase, selectivity of reactiv¬ ity, etc.

It is an object, therefore, of the present inven- tion to provide a pharmaceutically acceptable medicament for HLE-mediated pulmonary diseases. It is another object to provide such a medicament which may be administered by aerosolization. It is another object to provide a novel method for the treatment or prevention of elastase-mediated pulmonary diseases.

The present invention comprises a medicament for the prevention or medication of human leucocyte elastase- mediated pulmonary disease comprising a treatment effective amount of a polysulfated polysacchride. In accordance with the present invention, the present inventors have discovered that through the oral application of pharmaceutically effective quantities of polysulfated polysaccharides (PS) , as by the inhalation of a powder or liquid mist containing the compound, such PS effectively inhibit HLE-mediated diseases associated with the pulmonary tract. The pharmaceutically effective quanti¬ ty is selected to be in the range of about 10 mg to about 100 mg q6h of the PS, based on the inhibitory activity of the medicament and the load of HLE in the lung^'s. The dis- covery that such relatively low dosages of the PS are effec¬ tive permits the compound to be administered by aerosol, as opposed to intramuscular or intravenous administration which are recognized as potentially giving rise to adverse effects in vivo. Further, such discovery has provided the means for limiting the exposure of the body to the potentially damag¬ ing side effects of certain of the PS compounds which nov; appear to be partially a consequence of, or at least exacer¬ bated by, the prior art requirement that such compounds be administered in substantially sized dosages in order for them to be effective. Still further, the PS of the present invention have been found to effectively seek out the alvec- lar interstices and remain available for half-life time periods that permit the administration of the compound in amounts and at times that are reasonable and acceptable for patients. To this end, the present compounds have been found effective when administered orally as by_. inhalation at intervals of up to about eight hours. The sulfated polysac¬ charides of the present invention are "naturally occurring" and commonly are present in the extracellular matrix. The fact that sulfated polysaccharides of the present invention are normal constituents of lung matrix, indicates that these compounds provide a tissue based protection of elastin from HLE-mediated proteolysis, thereby differentiating the present compounds from other compounds known to provide in vivo inhibition of elastolytic activity.

The compounds of the present invention are revers- ible as regards their inhibitory effect upon elastase. That is, the elastase is inhibited as by the electrostatic bind¬ ing of the PS to the opposite ends of the elastase molecule, leaving the effective center portion of the elastase mole¬ cule unaltered. Importantly, the compounds of the present invention remain extracellular so that they are available to inhibit extracellular elastase without disruption of the desirable and beneficial function of intracellular elastase, which in its "natural" and effective state is a host defense against bacteria. Further, the PS compounds of the present invention are not subject to being rendered ineffective by oxidants in the pulmonary tract, they are not adversely affected by normal pH fluctuations in the tract, and they are selective in that they do not attack the parenchyma tissue nor inhibit the normal functioning of other desirable metabolic activities, including desirable proteolytic activ¬ ities. The present PS compounds have been found to not induce adverse hemorrhaging, and in fact have been noted tc effect a reduction in established hemorrhaging due to elas- tase-induced diseases in the pulmonary tract.

The present PS compounds, when administered in accordance with the present disclosure are considered effec- tive in the treatment of any HLE-mediated disease of the pulmonary tract. For example, it is known that the bacte¬ ria, Pseudomonas aeruqinosa, is commonly present in the pulmonary passages of normal persons but such persons do not contract pneumonia. However, up to two percent cf the patients entering hospitals contact pneumonia and of these patients, 50% die from such hospital-contacted pneumonia. The present PS compounds, inhaled routinely in the course of a hospital stay, are deemed to provide prophylactic protec¬ tion against such pneumonia, most likely by reason of the fact that the present PS compounds inhibit the development of colonization sites for the bacteria by the proteolytic activity of elastase in the pulmonary tract.

FIGURE 1 is a graphical representation of data indicating the inhibition of HLE by sulfated polysaccha- rides. The substrate used was suc-ala2~val-pNA.

FIGURES 2A, 2B and 2C are graphical representa¬ tions of data showing the effect of GAGPS on acute lung injury induced by HLE. FIGURE 2A depicts the hemoglobin/ml lavage, FIGURE 2B depicts the protein/ml lavage, and FIGURE 2C depicts the granulocyte count/ml lavage.

FIGURES 3A, 3B and 3C are graphical representa¬ tions depicting the effect of GAGPS on HLE-mediated emphyse¬ ma as indicated by quantification of the alveolar intercepts in randomly selected fields for each lung examined. In FIGURE 3A, 6K GAGPS was administered four hours after the HLE; in FIGURE 3B, 10K GAGPS was administered simultaneously with the HLE; and, in FIGURE 3C, 19K GAGPS was administered four hours after the HLE. In all instances, the extent c: emphysema was reduced after addition of the GAGPS a a re¬ mained reduced for up to eight hours.

FIGURE 4 is a graphical representation depicting the effect of dextran sulfate on acute lung injury induced by HLE as represented by the analysis of protein in lavage.

FIGURE 5 is a graphical representation depicting the effect of dextran sulfate on acute lung injury induced by HLE as represented by the analysis of hemoglobin in lav- age.

In accordance with the present invention, the preferred inhibitor is dextran sulfate having the following formula:

where: n = .S0₃-, H

Rτ_, R₂ and R₃ each = a lower alkyl

This compound is a derivative of dextran, or polyglucose composed of alpha-D-glucopyranosyl units linked predominantly alpha-D(1→6) and differing only in chair, length as defined in The Merck Index, 10th Ed., 19SΞ; 426. Dextran is produced by bacteria growing on a sucrose sub¬ strate. A number of methods of production exist, including methods of removing pyrogens, and for producing clinical dextran (U.S. Patent Nos. 2,762,727 and 2,972,567) . Dextran sulfate is prepared by boiling dextran with sulfuric acid to reduce the molecular weight and esterifying the degraded dextran with chlorosulfonic acid in pyridine as described in U.S. Patent No. 2,715,091, which patent is incorporated herein by reference.

The activity of dextran sulfate was tested by- monitoring the ability of HLE purified from an extract of polymorphonuclear leukocytes using Matrex Gel Orange A chromatography followed by cation exchange chromatography on Bio-Rex 70 as described by Kao et al , Proteinase 3: A Dis¬ tinct Human Polymorphonuclear Leukocyte Proteinase" That Produces Emphysema in Hamsters, J. Clin Invest 1988; 82:1963-1973 to cleave the synthetic elastase substrate succinyl-tri-alanyl-p_-nitroanilide, causing an increase in spectrophotometric optical density at 405 nm. The reaction was run in 0.125 M HEPES buffer (pH 7.5) containing 0.125% Triton X-100, 3 M substrate, 20 μg/ml of HLE and various molar ratios of elastase to inhibitor. Various molecular weight fractions of dextran sulfate were tested, the results being depicted in Table I.

TABLE I EFFECT OF DEXTRAN SULFATE AND DEXTRAN ON HLE

B.

0 20 27 49 62 77 82 95

0

0 0

0 0 0

0 As shown in Table I, dextran alone provides no inhibitory activity toward HLE. On the other hand, the inhibitory activity of dextran sulfate is almost complete at a ratio of 1:2 elastase to inhibitor. Such activity is thus a function of the molecular weight of the dextran sulfate and its degree of sulfation.

Chrondroitin sulfate having a molecular weight of 55,000 Daltons (purchased from Sigma Chemical of St. Louis, MO.) and heparan sulfate having a molecular weight of 40,000 Daltons purified from EHS sarcoma as described by Hassell et al. Isolation of a Heparan-sulfate Contain¬ ing Proteoglycan From Basement Membrane, Proc. Natl. Aced. Sci. USA, 1980; 77:4494-4498, were tested for inhibitory activity in like manner to the testing of dextran sulfate. The results of such tests are given in Tables II and III. TABLE II

EFFECT OF CHONDROITIN SULFATE

ON HLE

TABLE III

EFFECT OF HEPARAN SULFATE

ON HLE

Ratio of Elastase O.D. Change Inhibition to Inhibitor at 405 nm

1.0 0.096 0

1:0.1 0.083 14

1:0.2 0.052 46

1:0.4 0.029 70

1:0.5 0.024 75

1:1 0.017 82

Both chrondoitin sulfate and heparan sulfate inhibited elastase in vitro almost completely at a 1:1 ratio of inhibitor to elastase.

In further testing, the activity of HLE was monitored using the specific synthetic chromogenic sub¬ strate suc-ala₂-val-pNA. The method used is described by Barrett, A. J. , Cathepsin G, Methods Enzy ol. 1981; 80: 561-565 with modifications. The assay mixture of 1 ml contained 0.3 mM substrate (100 μl 3 mM in DMSO) in 50 mM HEPES buffer, pH 7.5. The reaction was started by addi¬ tion of 100 μl of HLE (20 μg/ml) . Activity against the substrate was determined by release of 4-nitroaniline as indicated by an increase in OD at 405 n over 3 minutes. Inhibition was assessed by preincubation of HLE with sulfated polysaccharides for 30 min at 37°C prior to initiating the reaction. Tests were performed employing dextran sulfate, heparin, heparan sulfate, chondroitin sulfate, dextran sulfate and dextran. The results of these tests are presented in Figure 1 wherein it is noted that each of these additional compounds in a concentration of less than 400 ng/ml is an effective inhibitor of HLE.

The activity of HLE itself was also assessed with insoluble elastin as the substrate. Bovine ligament elastin was prepared by the method of Starcher and Galione (Starcher et al , Purification and Comparison of Elastins from Different Animal Species, Anal Bioche 1976; 74:411- 447) and assessed for purity by amino acid analysis. Its degradation was assayed using elastin radiolabelled with [³H] NaBH⁴ following the methods described by Stone et al , Proteolysis of Insoluble Elastin, Methods Enzymol 1982: 82:588-605. The tritiated powdered elastin was homoge¬ nized and washed in PBS, pH 7.4. The reaction mixture containing the reference enzyme or sample preincubated with inhibitor was added to a 5 mg aliquot of ³H-elastin and incubated at 37°C, pH 7.4. Solubilized peptides were separated from the elastin suspension by filtration through medium porosity filter paper. The rate of degra- dation was determined by quantifying the ³H-peptides solubilized. Table IV presents the results of these tests and indicates that GAGPS of molecular weights between about 6,000 and 19,000 Daltons effectively reduces the HLE activity at molar ratios of HLE to GAGPS as low as about 1:0.2 at the higher molecular weights while requiring higher ratios, i.e. above about 1:0.5 at the lower molecu¬ lar weights. TABLE IV HLE ACTIVITY AGAINST ³H-ELASTIN IN PRESENCE OF GAGPS

GAGPS

The ability of polysulfated polysaccharides to prevent HLE-mediated acute lung injury was assessed in female Syrian golden hamsters (Harlan Industries, Indian¬ apolis, IN.) weighing 90-110 g. Pentobarbital anesthe¬ tized hamsters were injected intratracheally with 0.25 ml sterile 0.9% saline (NS) or 0.25 ml NS containing frac¬ tions of Arteparon (GAGPS) , a supersulfated derivative of chondroitin sulfate, having respective molecular weights of 2,800, 10,000 and 19,000 Daltons and with a limited degree of polydiversity. These injections of GAGPS were followed at timed intervals by injection of HLE in 0.25 ml NS. Twenty-four hours after the treatment, anesthetized animals were sacrificed by exsanquination. The thorax was opened and the lungs dissected en bloc. The lungs were weighed and the trachea was cannulated with polyethylene tubing and lavaged with 5 sequential aliquots of 3 ml NS. The volume of lavage returned was similar in all groups and always <__. 80% of that instilled. Lavage fluid was centrifuged at 200 g for 10 minutes. The resulting cell pellet was resuspended in 1 ml Hank's Balanced Salt Solu- tion (HBSS) for performing cell count and diffeentials. The supernated was assayed for protein and hemoglobin, as indices of acute injury.

Visual observation of the excised lungs of the hamsters injected with HLE alone showed gross injury by hemorrahage and microscopically in intralveolar bleeding and inflammation. The latter was monitored by assessing hemoglobin, protein and polymorphonuclear leukocyte con¬ tent in lung lavage fluid. The data obtained is presented in Figures 2A, 2B and 2C. As evident from the data in these Figures, GAGPS markedly protected hamster lungs from acute injury, not only preventing increase in lung weight from edema, and the increase in hemoglobin and protein in the lavage fluid, but also attenuated the influx of leuko- cytes into the alveolar space. Essentially total protec¬ tion was obtained when GAGPS was injected within 4 hours of HLE administration. GAGPS administered 8 hours prior to HLE had a modest protective effect. Similar effects were obtained with each of the three molecular weight fractions which had effectively inhibited HLE in vitro. Dextran sulfate also markedly protected lungs from acute lung injury in like tests.

The prolonged interval of protection after a single instillation of GAGPS indicates a long residence time within the lungs. Such was assessed by determining the rate of clearance of ³H-GAGPS from the lungs. To determine the fate of GAGPS in the pulmonary tract, cer¬ tain of the hamsters were sacrificed at timed intervals after administration of 0.25 ml of NS containing 136 μg of ³H-GAGPS (1.60 x 6¹⁰ cp ) . The lungs were weighed and lavaged as described hereinabove. A 20% homogenate by weight was made of the lungs after lavage. An aliquot of homogenate was digested with tissue solubilizer (NCS) at 50°C, and the sample was then bleached with 30% hydrogen peroxide before adding to 10 ml of Hydrofluor. The ³H content was determined by scintillation counting. Ali- quots (1 ml) Of each lavage fluid sample was similarly counted. Results were expressed as % of the intratracheal dose of cmp administered that was present in lung/lavage at the time of sampling. Data showing such rate is pre¬ sented in Table V. After 15 minutes following instilla- tion, 30% of the administered radioactivity had disap¬ peared. Thereafter there was a progressive decrease in the ³H activity recovered in the lavage fluid. Ten per¬ cent of the adminstered radiactivity was recovered in the lavage after 8 hours. Importantly, the portion of the radioactivity resident in the lung after lavage (8%) re mained stable over 24 hours, thereby indicating that ³H- GAGPS rapidly pools into a long-lived lung reservoir which has a long half-life.

TABLE V FATE OF ³H-GAGPS ADMINISTERED INTRATRACHEALLY

TO HAMSTER LUNGS

% of Intratracheal ³H-GAGPS Recovered

Time Lung Lavage

15 in 7.5 64 i _nr 7.8 37

4 hr 7.7 21

8 hr 9.6 10

24 hr 7.4 6.5

In the compounds of the present invention, it is required that there be present significant quantities of the anion -SO^3". Whereas it is not known with certainty, it is believed that the interaction between GAGPS and HLE most likely occurs by the formation of electrostatic bonds between the negatively charged sulfate groups in the polysaccharide and positively charged guanidium groups of the arginine residues located at the surface of the highly basic enzyme. It further appears that the interaction does not influence the active center of the enzyme, but causes an indirect loss of catalytic activity. The effects of GAGPS on HLE-mediated emphysema were examined. These studies employed the same mass ratios and regimens as outlined hereinabove in assessing acute lung injury. The animals were sacrificed eight weeks after receiving HLE with or without GAGPS. The lungs were excised and inflation fixed. The extent of emphysema was determined on coded randomized sections by quantifying the alveolar intercepts in 20 randomly select¬ ed fields for each lung. HLE administered to the animals caused prominent airspace enlargement as indicated by a decrease in the number of alveolar intercepts. These observations are depicted in Figures 3A, 3B and 3C. Protection from emphysema was obtained when the standard preparation of GAGPS (10K Daltons) was administered at a mass ratio of 1:5 (enzyme to inhibitor) within 4 hours of the subsequent delivery of HLE. Pretreatment by 8 hours was not effective. In contrast, the 6K Dalton fraction of GAGPS preparation was not effective in protecting from HLE-mediated emphysema at any pretreatment level. Howev- er, the 19K Dalton fraction of GAGPS protected when admin¬ istered up to 8 hours prior to administration of the HLE. Thus, the 10K and particularly the 19K Dalton fractions effectively attentuated the HLE-induced emphysema.

Whereas the present compounds have not been tested in humans, it is noted that those adverse effects of heparin and Arteparon which have been noted heretofore appear to be a function of the molecular weight fraction heretofore employed. For example, Arteparon and heparin, which are administered intramuscularly or intravenously, and in relatively large dosages, comprise molecular weight fractions of greater than 100,000 Daltons. In the present invention, sulfated polysaccharides of a molecular weight of less than about 20,000 Daltons have been found effec¬ tive and are preferred. Further, the present inventors have discovered that, in the instance of the pulmonary diseases prevented or mediated by the presently disclosed compounds, the elastase is present in the pulmonary tract in relatively small quantities, hence the present inven¬ tors have further found that relative small dosages of the polysulfated polysaccharides are effective to provide at least 80% or better inhibition of the elastase in the pulmonary tract. This has been found to be true at elas¬ tase to inhibitor ratios of between about 1:0.2 to 1:5. Thusly, the exposure of the patient to relatively large quantities of the polysulfated compounds is minimized, to the point that no adverse effects in hamsters has been noted when the compounds are administered to healthy animals. When administered to animals suffering from elastase-mediated diseases of the pulmonary tract, the compounds provide marked therapeutic improvement, includ¬ ing full recovery from the disease without adverse side effects. Further, as noted hereinabove, the compounds of the present invention, administered by aerosolazation, function extracellularly, thereby minimizing adverse condi¬ tions such as disruption of normal immunoreactivity and the like. The present compounds, present extracellularly, of relatively low molecular weight, and administered in relatively small dosages are not indicated to be adverse in humans, especially in view of the observed favorable acceptability in aminal models. The long effective resi¬ dence time in the host of the present compounds, along with their other noted characteristics, indicates their usefulness in the treatment of both chronic and/or acute HLE-mediated lung diseases, including emphysema, cystic fibrosis, etc.

The sulfated polysaccharides of the present invention are normal constituents of the lung matrix. It has been noted by the present inventors that the present compounds are indicated to provide a tissue based protec¬ tion of elastin from HLE-mediated proteolysis. This observation points out the uniqueness of the present compounds for use in the prevention and treatment of pulmonary diseases. This specificity of the present compounds further suggests a basis for the observed de- sired inhibitory activity of these compounds without noted deleterious effects upon those concomitant desirable and necessary metabolic activities within the pulmonary tract parenchyma.

Claims

CLAIMS :

1. A medicament for the prevention or mediation of human leucocyte elastase-mediated pulmonary disease comprising a treatment effective amount of a polysulfated polysacchride.

2. The medicament of Claim 1 wherein said medicament is administered by aerosolization.

3. The medicament of Claim 1 wherein said polysacchride is selected from the group comprising GAGPS, dextran sulfate, chrondroitin sulfate, heparan sulfate and their derivatives.

4. The medicament of Claim 1 wherein the ratio of elastase to polysaccharide in the lung is between about 1:0.2 and about 1:5.

5. The medicament of Claim 1 wherein said polysaccharide has a molecular weight of less than about 100,000 Daltons.

6. The medicament of Claim 1 wherein said treatment effective amount is determined as a function of the quantity of human leucocyte elastase present extracel¬ lularly in the pulmonary tract.

7. The medicament of Claim 1 wherein an effec¬ tive amount of said polysaccharide remains extracellular within the pulmonary tract.

8. The medicament of Claim 1 wherein said poly saccharide binds substantially with the reactive ends of the molecules of human leucocyte elastase, leaving the catalytically-active central portion of said molecules free.

9. A method for the treatment of human leuco¬ cyte elastase-mediated diseases of the pulomonary tract comprising the administration by aerosolization of a treatment effective amount of a polysulfated polysaccha- ride to an afflicted host.

10. The method of Claim 9 wherein said polysul¬ fated polysaccharide is selected from the group comprising GAGPS, dextran sulfate, chrondroitin sulfate, and heparan sulfate.

11. The method of Claim 9 wherein said polysul¬ fated polysacchride comprises dextran sulfate.

12. The method of Claim 9 wherein said polysul¬ fated polysacchride is administered in an amount suffi¬ cient to provide a ratio of human leucocyte elastase to polysulfated polysacchride of between about 1:0.2 and about 1:5.

13. The method of Claim 9 wherein an effective amount of said sulfated polysaccharide remains substan¬ tially extracellular within the pulmonary tract.

14. The method of Claim 9 wherein said polysul¬ fated polysaccharide comprises GAGPS.