Interaction of Plasma Kinins and Granulocytes

Identification of a tissue kallikrein in human polymorphonuclear leucocytes

We have identified a tissue kallikrein in polymorphonuclear (PMN) leucocytes of normal human blood and bone marrow by immunocytochemistry, radioimmunoassay and enzymology. Immunoreactive tissue kallikrein was visualized in the mature neutrophil leucocytes and in immature forms such as metamyelocytes and myelocytes. No tissue kallikrein was detected in eosinophil leucocytes, lymphocytes, macrophages, megakaryocytes and platelets. So far, we have failed to observe immunoreactivity to tissue kallikrein in basophils. The presence of tissue kallikrein in extracts prepared from PMN leucocytes isolated from peripheral blood was demonstrated by immunodiffusion, dot-blotting and by radioimmunoassay. The kininogenase and amidase activity of the extracts resembled that of tissue kallikrein in being resistant to soya bean trypsin inhibitor and sensitive to trasylol. The amidase activity attributable to tissue kallikrein was completely inhibited by specific antisera.

Presence of immunoreactive tissue kallikrein in human polymorphonuclear (PMN) leucocytes

The presence of tissue kallikrein in polymorphonuclear (PMN) leucocytes from normal human blood and from patients with rheumatoid arthritis and pyelonephritis was investigated. Immunoreactive tissue kallikrein was specifically detected in neutrophil leucocytes. PMN leucocytes displayed a granular staining. In the synovial membrane and kidney, the cells were aggregated into pockets as part of an inflammatory infiltrate. The presence of immunoreactive tissue kallikrein in human PMN leucocytes may provide a new insight into the importance of this enzyme in inflammation.

Role of the kallikrein-kinin system in human pancreatitis

Various factors in the kallikrein-kinin system were evaluated in acute and chronic pancreatitis. It was noted in particular that plasma trypsin and glandular kallikrein increased markedly in acute phase of pancreatitis and its correlation with amylase was observed. Plasma prekallikrein (PPK) decreased in acute pancreatitis, but increased in chronic pancreatitis. A negative correlation was noted between PPK and kallikrein like activity. Both HMW and LMW kininogen decreased in acute pancreatitis. It was presumed from these findings that the increase in kinin and its activation at the acute phase of pancreatitis might be due to kallikrein or trypsin originating from the pancreas.

Possible involvement of angiotensin I-converting enzyme in the inactivation of bradykinin by intact macrophages

As intact macrophages inactivated bradykinin, the subcellular localization of the bradykinin-inactivating activity was studied using guinea-pig macrophages. The bradykinin-inactivating activity was found to be present in membrane and cytosol fractions but not in granular and nuclear fractions. The bradykinin-inactivating activity of the membrane fraction was inhibited by captopril, a specific inhibitor of angiotensin I-converting enzyme, whereas that of the cytosol fraction was hardly inhibited by various proteinase inhibitors used. Angiotensin I-converting enzyme activity was located predominantly in the membrane fraction and its activity was inhibited by captopril. Angiotensin I-converting enzyme activity measured with a synthetic substrate was competitively inhibited by bradykinin, suggesting that bradykinin is a possible substrate for macrophage angiotensin I-converting enzyme. When macrophages were modified chemically by diazotized sulfanilic acid, a poorly permeant reagent, both the bradykinin-inactivating activity and the angiotensin I-converting enzyme activity of macrophages decreased significantly without any inhibition of the cytosol bradykinin-inactivating activity. These findings seem to suggest that the angiotensin I-converting enzyme would be responsible for the inactivation of bradykinin in intact macrophages.

Possible involvement of aminopeptidase, an ecto-enzyme, in the inactivation of bradykinin by intact neutrophils

The subcellular localization of the bradykinin-inactivating activity was studied using guinea-pig neutrophils and the following results were obtained. The bradykinin-inactivating activities were found to be present in the cytosol and membrane fractions but not in the granular and nuclear fractions. The bradykinin-inactivating activity of the cytosol fraction was inhibited by N-carbobenzoxy-Gly-Pro, an inhibitor of prolyl endopeptidase, whereas that of the membrane fraction was inhibited by bestatin, an inhibitor of aminopeptidase. Prolyl endopeptidase and aminopeptidase activities were located predominantly in the cytosol and membrane fractions, respectively, and their activities were inhibited by their respective inhibitors. Prolyl endopeptidase and aminopeptidase activities measured with synthetic substrates were competitively inhibited by bradykinin, suggesting that bradykinin is a possible substrate for prolyl endopeptidase and aminopeptidase. Intact neutrophils inactivated bradykinin rapidly. However, when neutrophils were modified chemically by diazotized sulfanilic acid, a poorly permeant reagent which inactivates ecto-enzymes selectively, both the bradykinin-inactivating activity and aminopeptidase activity of neutrophils decreased significantly without any inhibition of cytosol prolyl endopeptidase. The possibility that aminopeptidase, an ecto-enzyme, would be responsible for the inactivation of bradykinin by intact neutrophils was deduced from the results above, although both cytosol prolyl endopeptidase and membrane aminopeptidase could inactivate bradykinin.

Plasmodium berghei: physiopathological changes during infections in mice

Using infections of Plasmodium berghei in laboratory mice, the following physiopathological changes were observed during the seven days of the infection: reduction in haematocrit, increases in parasitized erythrocytes, pulmonary oedema, hypothermia, formation of prostaglandin-like substances in the central nervous system, increases and decreases in plasma bradykininogen levels and leucocytosis, as evidenced by neutrophilia, lymphocytosis and monocytosis. We found no changes in total plasma protein levels and albumin/globulin ratio.

Role of medullasin in granulocytes in the development of inflammation. I. Phlogistic activity and the effect on functions of macrophages and granulocytes

Injection of a small amount of medullasin protease (20 micrograms) into the skin of guinea pigs or rabbits caused inflammation characterized by severe injury to endothelial cells in venules and by infiltration of a large number of macrophages. Medullasin inhibited macrophage chemotaxis in vitro, stimulated granulocyte chemotaxis, and potentiated the production of superoxide by macrophages. These results indicate that medullasin in granulocytes plays an important role in the development of inflammation.

Current concepts in soft connective tissue wound healing

The strength and integrity of intact soft connective tissues are related to the forces which exist between collagen fibrils and these in turn appear to depend on collagen fibril size, density and architecture en masse. The genetic type of collagen, enzymic modifications to the collagen monomer and the proteoglycan environment all affect fibril size. Current evidence suggests that the restoration of tissue continuity and the early redevelopment of tissue strength following wounding are initially achieved by the formation of a myofibroblast-reticulin network which eventually disappears as the healing wound ages. The extent of this network defines the area in which repair tissue will be laid down and the network is equipped with the sensory apparatus to monitor the physical and chemical environment where healing is taking place and thus to direct the various facets of connective tissue synthesis outlined above. The maturation of the scar connective tissue matrix and the development of attachment between new and original connective tissues are simultaneous, related but independent processes. It takes some time before the weld is achieved by the same forces that hold connective tissue fibres together in intact tissues and the myofibroblast-reticulin network is replaced.

Experimental post-traumatic lung insufficiency in dogs: ultrastructure of lung lesions

The ultrastructure of developing lung lesions in two groups of dogs exposed to a combination of haemorrhagic hypotension and liver trauma was studied with particular attention to changes at the alveolar level and lung micro-vessels. Lung samples were obtained every four hours and at collapse in one group and 12 hrs after initiation of the trauma in the other. An interstitial oedema was recognized in biopsies obtained 4 hrs after initiation of the trauma, and before marked lesions were observed at the ultrastructural level in endothelial cells. Endothelial damage was, however, evident in biopsies obtained at 8 hrs and at collapse. Aggregates of degranulated and degenerated leucocytes and platelets were occasionally found to obstruct respiratory capillaries together with erythrocytes, some of which seemed to be haemolysing. A considerable amount of protein-rich oedema, cellular debris and fibrinoid material was found in alveolar lumina at collapse. The present experiments indicate that increased vascular permeability in lung micro-vessels is of importance for the development of the characteristic lesions seen in shock lung. Possible pathogenetic mechanisms, initiating the lung lesions, are discussed with special emphasis on the significance of kinin activation and the presence of polymorphonuclear leucocytes and microthrombi.

The role of polymorphonuclear leukocytes in delayed hypersensitivity skin reactions: suppressive effects of anti-polymorphonuclear leukocyte serum

Rabbit antisera (APS) against normal guinea pig peritoneal exudate polymorphonuclear leukocytes (PMN), when injected intraperitoneally three times within 24 h into guinea pigs, lead to a marked fall in the blood PMN count (below 100/mm3) 24-72 h after the injection and a mild depression in the number of circulating mononuclear leukocytes (MNC) at 36-72 h. APS treatment of guinea pigs led to a marked suppression of delayed hypersensitivity skin reactions in response to dinitrophenylated bovine gamma-globulin. The volume, induration, mean diameter of the reaction and leukocyte (both PMN and MNC) emigration into local sites were suppressed, as was, to a lesser extent, vascular permeability. Based on these observations it appears that circulating PMN are required for the full expression of delayed hypersensitivity reaction engendered by bovine gamma-globulin.

Experimental gingivitis in ODU plaque-susceptible rats. V. The presence of bradykinin in the gingival tissue and the bradykinin inactivating factor in rat dental plaque

Plaque formation and gingival inflammation were found in ODU plaque-susceptible rats. A study was performed to determine the relationship between the presence of bradykinin in gingival tissue and the inflammatory capacity of rat plaque. Bradykinin content in gingival tissue and the bradykinin inactivating activity of dental plaque of 12-month-old ODU rats were measured. The presence of bradykinin was observed in the gingival tissue of the ODU rat and a bradykinin inactivating factor was found in the rat plaque. The factor was destroyed at 60 degrees C for 30 minutes, at pH 1.5 or by treatment with perchloric acid. The optimum pH of the factor was approximately 8.0. Chelate reagents, such as O-phenanthroline and EDTA . 4Na, strongly inhibited the bradykinin inactivating factor. The protease inhibitor, Trasylol, also inhibited this factor. The SH reagent, L-cysteine, inhibited weakly and Zn++ inhibited less. The investigation suggested that the rat plaque posseses the ability to inactivate bradykinin and plays an important role in modifying the inflammatory response caused by bradykinin in gingival tissue.

Importance of platelets in increased vascular permeability evoked by experimental haemarthrosis in synovium of the rat

Increased vascular permeability of synovium induced by experimental haemarthrosis was studied in the stifle joint of the rat. Abnormal permeability was detected by injecting animals intravenously with colloidal carbon and examining the synovial vessels for intramural deposits of carbon. Both fresh and heparinized whole blood injected into the joint induced a marked permeability response of synovial venules which persisted for 18 hours. Platelets suspended in heparinized Tyrode solution induced a similar response, but one lasting only 12 hours. The permeability effects of suspensions of leucocytes and erythrocytes on the synovial vasculature were relatively mild and were maximal 5 and 12 h respectively after intra-articular injection. Heparinized platelet-free plasma had no significant permeability effects. These results indicate that platelets may play an important role in the pathogenesis of synovial inflammation in haemarthrosis.

Fatal anaphylaxis in systemic mastocytosis

A 42-year-old woman died after an episode of anaphylaxis associated with a raised serum histamine level. A diagnosis of systemic mastocytosis was established, with lymphadenopathy and hepatosplenomegaly, not associated with the usually pre-existing skin lesions of urticaria pigmentosa.

Intracellular enzymes and kinin enzymes in synovial fluid in joint diseases. Origin and relation to disease category

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PMN-kinin and kinin metabolizing enzymes in normal and malignant leucocytes

1. Studies have been carried out on the kinin-forming and kinin destroying activity of rabbit macrophages obtained from the lung before and after BCG injection and from the peritoneal cavity following mineral oil injection. A similar study was carried out with L-1210 leukaemic cells obtained from the peritoneal cavity of mice.2. The macrophages and leukaemic cells contain enzymes that form kinins from purified kininogen substrates at acid pH. The kinin-forming activity is not limited to the lysosomal fraction of the cell since it is found in extralysosomal compartments. Delta-guanidovaleryl benzyl ester partially inhibits the kinin-forming activity. Trasylol does not inhibit the kinin-forming activity of these cells, but does inhibit the kininases of these cells. The lack of effectiveness of this agent as a general anti-inflammatory agent is thus explained.3. The kininases of the normal and malignant cells are also inhibited by chloromethyl ketones such as tosyl-lysine chloromethyl ketone (TLCK) and tosyl-phenylalanine-chloromethyl ketone (TPCK) as well as by copper salts. Hydroxyquinoline has no inhibitory action on these cells, indicating that they differ from the plasma kininases.4. Investigation of the kinins produced by enzymes in rabbit and human polymorphonuclear (PMN) cells has demonstrated the formation of a kinin that differs from bradykinin and other known mammalian kinins in its pharmacological properties, molecular weight, and amino-terminal end group. This peptide has been named PMN-kinin.5. Overall, the investigation has demonstrated the importance of white cells in contributing to the formation and destruction of "extra-plasma" sources of kinins by enzymes which differ from plasma enzymes. Anti-inflammatory agents may have different actions on these cell enzymes from those on plasma enzymes.

Edema angioneurotic hereditário e epilepsia tipo visceral

É relatado um caso de edema angioneurótico hereditário que, além de sintomas cutâneos, gastro-intestinais e respiratórios, apresentava sintomatologia neurológica com quadro de epilepsia visceral, além de crises convulsivas focais faciais e durante as crises, alterações eletrencefalográficas focais. A dosagem do complemento total (CH50) permitiu o diagnóstico de edema angioneurótico hereditário, tendo sido feito também o diagnóstico de epilepsia visceral, levando em conta não só a sintomatologia, como o resultado dos eletrencefalogramas e a prova terapêutica. O desaparecimento de toda a sintomatologia após medicação anticonvulsiva constitui dado interessante, merecendo ser investigado em outros casos. Considerando a semelhança clínica da eólica abdominal produzida por epilepsia visceral e por edema angioneurótico hereditário, bem como a coexistência, no caso apresentado, de edema angioneurótico hereditário e epilepsia visceral, fica ressaltada a importância de futuras investigações clínico-laboratoriais, visando estabelecer possível relação etiológica entre estas entidades clínicas.

Kinins and anti-inflammatory steroids

1. This investigation was designed to re-examine the possibility that anti-inflammatory steroids interfere with the kinin-forming system.2. We conclude that the anti-inflammatory action of corticosteroids cannot be explained by the inhibition of kinin formation. This view is based on the following findings.3. Neither hydrocortisone nor prednisolone nor dexamethasone inhibited the activation or activity of intrinsic plasma kinin forming enzymes resulting from dilution, incubation with kininase inhibitors, or exposure to glass, monosodium urate microcrystals or to precipitated complexes of rheumatoid factor and aggregated human gamma-globulin.4. Hydrocortisone did not inhibit the action of the active kinin-forming enzymes, human salivary or urinary kallikrein, or plasmin on purified kininogen.5. Hydrocortisone, prednisolone and dexamethasone did not inhibit the hydrolysis of benzoyl-arginine-ethyl ester by human plasmin, plasma kallikrein or hog pancreatic kallikrein.6. Kinin formation occurred normally in plasma taken from two patients receiving betamethasone and one receiving prednisone.