PATHOGENESIS OF INFLAMMATION. I. THE PRODUCTION OF AN INFLAMMATORY SUBSTANCE FROM RABBIT GRANULOCYTES IN VITRO AND ITS RELATIONSHIP TO LEUCOCYTE PYROGEN

Narrow-Band Imaging of Laryngeal Images and Endoscopically Proven Reflux Esophagitis

Objective

To compare the difference between white light (WL) and narrow-band imaging (NBI) endoscopy in evaluating patients who had reflux laryngitis and esophagitis.

Study Design

Retrospective review of medical records and endoscopic images.

Setting

Outpatient clinic.

Subjects and Methods

There were 102 consecutive patients with reflux esophagitis (mean age, 48 ± 11 years) who had office-based transnasal esophagoscopy (TNE) with WL and NBI views, including 60 men (59%) and 42 women (41%). We compared WL and NBI endoscopy in observing the laryngeal and esophageal epithelium. The nasopharynx, base of the tongue, epiglottis, hypopharynx, larynx, esophagus, gastroesophageal junction, and stomach were examined, and all procedures were digitally recorded. All patients were evaluated with WL and NBI views to determine the reflux finding score (RFS) in the larynx and Los Angeles (LA) classification grade in the esophagus.

Results

The NBI views were more sensitive than the WL views in the erythema/hyperemia, vocal cord edema, and global RFS scores. The NBI view facilitated the identification of the erythema/hyperemia change representing dilation or proliferation of microvessels caused by epithelial inflammation. The global RFS score was significantly associated with severity of LA grade only with the NBI view.

Conclusion

The endoscopic findings with the NBI view permit an easier identification of the RFS parameters of laryngeal erythema/vocal cord edema, which have a stronger correlation with the severity of reflux esophagitis, than the WL view. The importance of NBI in the evaluation of reflux laryngitis and gastroesophageal reflux disease deserves further study.

PATHOGENESIS OF INFLAMMATION. II. IN VIVO OBSERVATIONS OF THE INFLAMMATORY EFFECTS OF ACTIVATED HAGEMAN FACTOR AND BRADYKININ

Activated Hageman factor, when injected into the rabbit ear chamber, produces a delayed and prolonged inflammatory response characterized by prominent sticking and emigration of leucocytes. In contrast, preformed bradykinin evokes an immediate and more transient response in which leucocytic emigration occurs less frequently. It is concluded that either Hageman factor produces its inflammatory effects by mechanisms other than kinin release, or bradykinin released endogenously has effects quite different from those resulting from a single injection of the exogenous material.

Differentiation between endogenous pyrogen and leukocytic endogenous mediator

The crude material released from glycogen-stimulated rabbit peritoneal polymorphonuclear leukocytes when administered to experimental animals elicits a number of metabolic and physiologic alterations characteristic of those observed in the host inflammatory response. Classically, the mediator of febrile response observed in rabbits and other species has been termed endogenous pyrogen (EP), whereas leukocytic endogenous mediator (LEM) has been used as a general term to denote the substance(s) mediating multiple inflammatory responses observed in rats. The latter substance, however, has not been previously demonstrated to differ from EP. This report presents evidence indicating that EP and LEM are different molecular species. Evidence supporting the differentiation between these entities includes: physical separation of EP from one or more mediators that induce metabolic alterations attributed to LEM; production of LEM activities by stimulated polymorphonuclear leukocytes in the absence of detectable pyrogenic activity; and differences in the release of EP and LEM from stimulated rabbit granulocytes in the presence of potassium ion.

Studies on the mechanism of endogenous pyrogen production. II. Role of cell products in the regulation of pyrogen release from blood leukocytes

Some characteristics of the process by which endogenous pyrogen (EP), the mediator of fever, is released from cells were examined by using human blood leukocytes incubated in vitro. Studies were designed to examine a possible role for leukocyte products, including EP, in the induction, augmentation, or suppression of pyrogen release by blood leukocytes. Products of stimulated leukocytes, including a partially purified preparation of EP, did not induce significant activation of nonstimulated cells. Also, no evidence was obtained that stimulated cell products either augment or inhibit pyrogen production by other stimulated cells. A feedback control of EP production was thus not observed. A crude preparation of EP, containing other products of activated cells, maintained its pyrogenicity when incubated at pH 7.4 but not at pH 5.0. These studies thus provide no support for hypothesized control mechanisms regulating production of EP by blood leukocytes. By contrast, local inactivation of EP at inflammatory sites may modify the amount of EP entering the blood, and hence fever.

Mediators of inflammation in leukocyte lysosomes. VI. Partial purification and characterization of a mast cell-rupturing component

The mast cell-rupturing component present in the lysosomes of rabbit exudate PMN neutrophil leukocytes has been identified and some of its physical and chemical properties have been described. The active agent is a low molecular weight (1200 to 2400) polypeptide containing a relatively large proportion of the basic amino acid, arginine. It is thermostable and dialyzable, and does not cause contraction of the isolated guinea pig ileum. The mast cell-rupturing activity of the agent is destroyed by trypsin. A second permeability factor with a larger molecular weight is present in crude extracts of PMN granules. Although this substance does not lyse mast cells, it is capable of evoking delayed permeability responses in rabbit skin.

Polymorphonuclear leukocytes in immunologic reactions. The destruction of vascular basement membrane in vivo and in vitro

Vascular basement membrane was disrupted in the presence of polymorphonuclear leukocytes (PMN's) during two immunologic reactions: The Arthus phenomenon and the reaction to locally injected antibody to vascular basement membrane. This disruption was evidenced by (a) the inability of the basement membrane to retain circulating carbon, by (b) loss of antigenic constituents, and by (c) electron microscopic observation showing actual gaps in the structure of the vascular basement membrane. The factors within PMN's responsible for damage to isolated glomerular basement membrane in vitro were found by isolation procedures to be cathepsins D and E. Cationic proteins of PMN's were separable from the cathepsins. While inducing vascular permeability upon injection, these basic proteins failed to inflict the severe damage to the basement membrane observed in Arthus and antibasement membrane reactions. It is concluded that the full expression of these immunologic lesions requires destruction of the basement membrane possibly brought about by cathepsins D and E. Some of the physicochemical properties of these pathologically active leukocytic factors are given.

The acute inflammatory reaction in the rabbit ear chamber with particular reference to the phenomenon of leukocytic migration

Responses to injections of various materials into rabbit ear chambers were studied by in vivo microscopy. The acute inflammatory responses provoked by injections of antibody-antigen complexes were both quantitatively and qualitatively different from the responses obtained after injections of either homologous sera or the antigens alone. The sticking of leukocytes to endothelium during these responses occurred only in the venules draining the injection sites and was frequently present only on the sides of the venules towards the injection sites. An explanation of this finding was proposed in terms of absorption by the minute vessels related to the injection sites of postulated mediator(s) with specific activity on venular endothelium. Analysis of the rates and direction of movement of leukocytes during the reactions produced by the antibody-antigen complexes was performed with the aid of time-lapse cinemicroscopy. The leukocytes that were sticking to the venular endothelium frequently exhibited amoeboid locomotion within the vessels. Twice as many of these cells moved against the direction of blood flow as with it. This finding was discussed and an explanation proposed. A method for detecting a drift in the overall population of emigrated leukocytes within the inflamed tissue was described and revealed that four times as many amoeboid cells moved away from the injection sites as towards them. This result was discussed in the light of the in vitro chemotactic properties of antibody-antigen complexes demonstrated for rabbit leukocytes. An alternative explanation was proposed in terms of variation in the population density of these cells and their random movements and collisions. The rates of amoeboid movement of leukocytes during the acute inflammatory reactions produced by antibody-antigen complexes were similar to the rates found during turpentine inflammation and were compared to other published values.

Crystal-induced inflammation in canine joints. I. An experimental model with quantification of the host response

Injection of sodium urate or calcium pyrophosphate crystals into the stifle joints of anesthetized dogs almost invariably induced an acute exudative response. This response was quantified by serial measurements of intra-articular pressure, pH and leukocyte concentration. Pressure rose progressively and reflected intra-articular volume increase. The hydrogen ion concentration increased as the reaction progressed and correlated in a given exudate with the leukocyte concentration. Analysis of sequential physiologic and biochemical changes occurring in this model of crystal-induced inflammation may provide insight into the mechanisms of acute gouty arthritis in man.

Mediators of inflammation in leukocyte lysosomes. II. Mechanism of action of lysosomal cationic protein upon vascular permeability in the rat

The vascular permeability-increasing action of rabbit PMNL lysosomes has been studied in skin and cremaster muscle of the rat. Both an extract of frozen-thawed granules and a cathepsin-free cationic protein fraction of the granules (which had previously been demonstrated to cause leukocyte adhesion and emigration in vivo) induce increased vascular permeability in skin and muscle which resembles that produced by histamine or histamine-liberators with respect to the timing of the response and the predominant type of microvessel affected. Extracts of frozen-thawed lysosomes and the inflammatory lysosomal cationic protein both cause disruption of rat mesenteric mast cells in vitro, whereas a granule-free cytoplasmic fraction of PMN leukocytes and a non-inflammatory cationic protein fraction of the granules do not do so under identical test conditions. The mastocytolytic action of lysosomal materials in vitro is not inhibited in the presence of 10 kallikrein-inhibiting units of trasylol per ml. The mast cell rupturing fraction of PMNL granules (cationic protein) possesses no detectable peroxidase activity or acid-mucopolysaccharase activity. When compared with compound 48/80 on the basis of estimated molecular weight, the lysosomal cationic protein appears to be at least as active as the latter compound with respect to in vitro mastocytolytic potency. Chronic pretreatment of rats with an agent known to reduce tissue mast cell numbers causes marked suppression of the vascular permeability change normally induced in skin and muscle by lysosomal extracts and cationic protein. Similar results are obtained if lysosomal materials are tested in rats pretreated with an antihistaminic. These observations are discussed with respect to the mode of action of PMNL lysosomes in the early and late phases of local tissue-injury reactions.