Inhibitory effects of dehydrocorydaline isolated from Corydalis Tuber against type I-IV allergic models

An alkaloidal component, dehydrocorydaline (DHC) isolated from Corydalis Tuber (tuber of Corydalis turtschaninovii forma yanhusuo), has been screened for activity against types I-IV allergic reactions. In a type I allergic models, DHC at a dose of 0.5 mmol/kg, p.o. inhibited 48 h homologous passive cutaneous anaphylaxis (PCA) in rats, which is related to IgE. DHC also exhibited an inhibitory effect on antigen-induced histamine release from peritoneal mast cells. In a type II allergic model, DHC did not inhibit reversed cutaneous anaphylaxis (RCA) in rats. In a type III allergic model, DHC showed weak inhibition on direct passive arthus reaction (DPAR) in rats. Furthermore, in a type IV allergic model, DHC had inhibitory effects on the induction phase and effector phase in picryl chloride-induced contact dermatitis (PC-CD). These results indicated that DHC not only inhibits antibody-mediated allergic reactions but also influences cell-mediated allergia reactions, and the inhibitory effect of Corydalis Tuber on allergic reactions may be partially attributed to DHC.

Development of antibodies to fetal calf serum with arthus-like reactions in human immunodeficiency virus-infected patients given syngeneic lymphocyte infusions

In an attempt to restore immune competence to 12 human immunodeficiency virus-1 (HIV-1)-infected patients, lymphocytes from their HIV-1-uninfected identical twin siblings were cultured in medium supplemented with 5% fetal calf serum (FCS), anti-CD3 antibody, and interleukin-2 (100 IU/mL) for 10 days and then infused into the patients. After multiple infusions, at 6- to 8-week intervals, half of the patients developed arthus-like reactions within 4 to 12 hours of infusion consisting of fever > 39 degrees C, hypotension, rigors, arthralgias, myalgias, headache, and/or malaise. Preinfusion and postinfusion serum samples were evaluated for the presence of antibodies to FCS using double immunodiffusion. All preinfusion serum samples were negative by this method while 8 of the 12 patients developed antibodies to a single component of FCS after two or more infusions of lymphocytes cultured in FCS-supplemented medium. Prick skin testing to standardized beef extract was negative in all patients. There was a correlation between initial CD4 level and the development of antibodies to FCS (median initial CD4 count in FCS antibody positive patients = 362.0/microL v median initial CD4 count of nonresponders = 135.0/microL). There was no correlation with response to recall antigens in delayed-type hypersensitivity testing. We conclude that selected patients were sensitized to a single component of FCS carried on donor lymphocytes, despite thorough washing of the cells before infusion. The development of antibodies to FCS indicates that immune complex formation could have occurred after the cell infusions, resulting in the arthus-like reactions. These observations suggest that the therapeutic use of human lymphocytes cultured in FCS may expose the recipient to immunogenic substances with possible clinical sequelae.

Immunotoxicological insignificance of fenitrothion in mice and rats

Fenitrothion was administered orally to mice or rats in daily doses of up to 1/25 of the LD50 for 14 days, and numbers of splenic plaque-forming cells against sheep red blood cells (SRBC-PFC), one of the most common immune parameters, were measured. Splenic SRBC-PFC number was suppressed by fenitrothion only in rats which received 30 mg/kg body weight (bw) of the compound. Other immune parameters, including the arthus reaction, delayed-type hypersensitivity, and activities of macrophages and natural killer cells in rats, were not influenced by fenitrothion. Adrenal hyperfunction manifesting as increased organ weight and elevated plasma corticosterone level was noted along with strong cholinergic signs in rats which received 30 mg/kg bw of fenitrothion. At lower doses such as 3 or 0.3 mg/kg bw of fenitrothion, rats had no strong cholinergic signs, adrenal hyperfunction, or evidence of immunosuppression despite significant suppression of systemic cholinesterase (ChE) activities. In mice, no suppression of SRBC-PFC number or mixed lymphocyte reaction was noted even at the highest dose (40 mg/kg bw) of fenitrothion, at which significant suppression of systemic ChE activities but no cholinergic signs were noted. These findings strongly suggest that the immunosuppressive effect of fenitrothion noted in rats was due to systemic, potent cholinergic stress and that fenitrothion has no immunotoxicity in mice and rats.

Impaired IgG-dependent anaphylaxis and Arthus reaction in Fc gamma RIII (CD16) deficient mice

The family of receptors for IgG (Fc gamma R) plays an essential role in antibody-mediated effector functions of the immune system. However, the specific contribution of each of the Fc gamma R classes to in vivo immune reactions is still unclear. Here, we demonstrate that mice deficient for the ligand-binding alpha chain of Fc gamma RIII lack NK cell-mediated antibody-dependent cytotoxicity and phagocytosis of IgG1-coated particles by macrophages. Strikingly, these mice lack IgG-mediated mast cell degranulation, are resistant to IgG-dependent passive cutaneous anaphylaxis, and exhibit an impaired Arthus reaction. These results indicate a prominent role for Fc gamma RIII in inflammatory and anaphylactic responses, making this receptor a potential target in immunotherapy.

Phenomenon of specific inhibition of luminol-dependent chemiluminescence of polymorphonuclear leukocytes under the influence of allergen

The purpose of our investigation was to establish how the intensity of induced luminol-dependent chemiluminescence of polymorphonuclear leukocytes is affected by the cultivation of allergen with the blood of allergic patients (pollinosis, bronchial asthma and penicillin allergy) and animals with allergic processes (Arthus' phenomenon, guinea pigs sensitized by horse serum). The results of all assays were uniform. In all cases three phases of changes in induced chemiluminescence were established. In the first phase with the minimum doses of specific and unspecific allergens, either no changes in chemiluminescence were found or chemiluminescence even increased. With higher doses of allergen came the second phase - inhibition of stimulated chemiluminescence when specific allergen had been added and the absence of changes in the tests with unspecific allergen. We defined this phase as the phase of specific chemiluminescence inhibition. With a further increase in the concentration of allergen came the third phase. It expressed itself in the inhibition of stimulated chemiluminescence under the influence of both specific and unspecific allergen. We viewed this phase as a manifestation of the toxic influence of allergen on polymorphonuclear leukocytes. We suggested using the second phase for diagnosing sensitization.

ICAM-1 mediates leukocyte-endothelium adhesive interactions in the reversed passive Arthus reaction

A murine anti-rat intercellular adhesion molecule 1 (ICAM-1) monoclonal antibody (mAb), 1A29, was used to investigate the importance of blood leukocyte-associated beta 2-integrin (CD11/CD18) vascular endothelium-associated ICAM-1 adhesive interactions in the reversed passive Arthus reaction (RPAR) in rats. An Arthus pleurisy reaction (4 h) was employed in these studies because it permits the accurate quantitation of polymorphonuclear neutrophil (PMN) influx into the pleural space and fluid accumulation. 1A29, which localized within Arthus lung lesions, caused a dose-dependent (0.5-2.0 mg/kg, i.v.) inhibition of PMN influx (19-56%) and exudate volume (9-55%) in the Arthus pleurisy reaction. P7 (2 mg/kg, i.v.), a murine anti-human P-selectin mAb used as an isotype-matched control for 1A29, did not localize at the lung lesion site and was inactive. Immunohistochemical analysis of lung tissue from 1A29-treated rats demonstrated increased granulocyte accumulation in the alveolar capillaries compared with more extensive granulocyte emigration into the lung tissue and pleural space in P7-treated rats and Arthus control rats; however, quantitative image analysis revealed increased numbers of lung granulocytes in 1A29-treated rats compared with controls. Neither ICAM-1 mRNA nor expression, assessed by immunocytochemistry, was increased above control levels in rats during the pleural Arthus reaction. Neutropenia was not observed in either 1A29- or P7-treated rats.

A functional analysis of recombinant soluble CD46 in vivo and a comparison with recombinant soluble forms of CD55 and CD35 in vitro

The human cell surface complement regulatory proteins CD46 (MCP), CD55 (DAF) and CD35 (CR1) protect autologous cells from complement-mediated damage by inhibiting C3 and C5 convertases. This regulatory potential has previously been exploited in the treatment of some models of inflammatory injury by the generation of recombinant soluble (rs) proteins, such as rsCD55 and rsCD35 . More recently, we have shown that rsCD46 inhibits complement activation in the fluid phase. In this report, the ability of rsCD46, rsD55 and rsCD35 to regulate human complement activation mediated by the classical pathway in vitro was clearly demonstrated by all three soluble proteins; however, rsCD35 was a more effective inhibitor than either rsCD46 or rsCD55. A combination of rsCD46+ rsCD55 was more potent than either of these proteins alone. Cell lysis via alternative pathway activation in vitro was efficiently regulated by rsCD46 and rsCD35 to a similar extent, whereas rsCD55 was not effective. Assays of rsCD46 in vivo have previously not been possible due to difficulties in expressing sufficient quantities of protein. This limitation has been overcome and now we report the ability of rsCD46 to inhibit immune complex-mediated inflammation in a rat using the reverse passive Arthus reaction model. Administration of rsCD46 significantly reduced the size of lesion, and histological examination showed a reduction in inflammatory infiltrate and edema. These data suggest that rsCD46, in addition to rsCd55 and rsCD35, may be useful a therapeutic agent.

Effect of soluble P55 tumour-necrosis factor binding fusion protein on the local Shwartzman and Arthus reactions

1. In this study, the effects of a protein synthesis inhibitor, cycloheximide, and a soluble tumour necrosis factor (TNF) binding/IgG fusion protein, p55-sf2, on the priming and challenge stages of the local Shwartzman reaction (LSR) were assessed and compared with their effects on the acute inflammatory response induced by recombinant human tumour necrosis factor-alpha (rhTNF), lipopolysaccharide (LPS) and a reversed passive Arthus (RPA) reaction in rabbit skin. 2. The LSR was induced in skin by giving an intradermal (i.d.) priming injection of LPS followed by two i.v. challenge injections 20 h and 22 h later. Accumulation of 51-Cr-labelled red blood cells and [125I]-albumin were measured at 24 h as markers of haemorrhage and oedema formation, respectively. 3. The RPA reaction was induced in the rabbit by giving i.d. injections of Arthus anti-serum (anti-bovine-gamma-globulin, BGG) followed 5 min later by an i.v. injection of the antigen (BGG). Oedema formation and the accumulation of 111In-labelled neutrophils produced in the RPA reaction and in response to i.d. injection of rhTNF and LPS were measured over the 4 h period after inducing the responses. 4. A single local injection of cycloheximide (10 micrograms/site) did not inhibit neutrophil accumulation or oedema formation produced by 100% Arthus anti-sera. Although LPS injected i.d. induced a marked dose-dependent neutrophil accumulation, there was little associated plasma leakage. Cycloheximide (10 micrograms/site) did not significantly inhibit the neutrophil accumulation induced by LPS (0.1 microgram/site). In the LSR, priming i.d. injections of LPS caused a dose-dependent increase in haemorrhage and plasma leakage at skin sites after challenge with LPS (two injections of 100 micrograms, i.v.). Co-injection of a single dose of cycloheximide (10 micrograms/site) with LPS (30 micrograms/site) caused a marked reduction in the amount of haemorrhage. Local cycloheximide (10 micrograms/site) administered immediately before LSR challenge did not affect the responses produced in the LSR. 5. Neutrophil accumulation induced by TNF (0.17 micrograms/site) was abolished by co-administration of p55-sf2 (3 micrograms/site) whereas neutrophil accumulation induced by i.d. LPS and produced in the RPA reaction was not affected. In the LSR, haemorrhage and oedema formation were inhibited by p55-sf2 (3 micrograms/site) when it was administered i.d. with the LPS priming injection, but not when given i.d. immediately before LSR challenge. 6. These data suggest that the acute neutrophil accumulation produced in the RPA reaction and in response to i.d. LPS may not be dependent on local protein synthesis or TNF production. On the other hand, haemorrhage appears to be dependent on local protein synthesis during the priming phase but not during the challenge stage of the LSR. Importantly, haemorrhage and plasma leakage appear to be dependent on local TNF generation during the priming phase but not during the challenge stage of the LSR. Thus TNF appears to play a key role in the LSR in rabbit skin.

Wessely-type immune ring following phototherapeutic keratectomy

Immune rings following photorefractive keratectomy (PRK) have been reported but have not been described in detail. This case report describes an immune ring after phototherapeutic keratectomy (PTK) in a patient with long-standing superficial corneal scars. A dense white ring formed in the peripheral cornea on the fourth day following surgery. The patient was treated with antibiotics until negative cultures were reported 48 hours later. A biopsy was taken and examined by light microscopy using hematoxylin-eosin and Mason's trichrome staining. The stroma showed focal keratocyte depopulation with nuclear fragments, occasional polymorphonuclear leucocytes, and an active fibroblastic reaction. No lymphocytes or plasma cells were seen. Clinically, the immune ring faded slowly and was still apparent 9 months after the PTK. Studies of similar cases are required to clarify the mechanisms responsible for this phenomenon.

Purification and functional properties of soluble forms of membrane cofactor protein (CD46) of complement: identification of forms increased in cancer patients' sera

Normal human sera contained 10-60 ng/ml of soluble membrane cofactor protein (MCP, CD46) whereas sera of > 50% of the cancer patients contained > 60 ng/ml. MCP purified by immunoaffinity chromatography from both normal and cancer patients' sera consisted of three bands of 56, 47 and 29 kDa on SDS-PAGE/immunoblotting. The upper two components were increased in cancer patient sera. The 56 and 47 kDa soluble forms served as a cofactor for factor I-mediated cleavage of C3b. MCP expressed on Chinese hamster ovary (CHO) cells protects host cells from human C3 deposition and complement-mediated cytolysis, especially by activation of the alternative pathway. In this same assay system, exogenously added soluble MCP also protected untransfected CHO cells; however, its potency was much less than that of the endogenous membrane form. For example, 8 micrograms/ml of soluble MCP was equal to 10(4) copies/cell of the expressed MCP. Recombinant soluble forms possessed similar activity to the naturally occurring soluble forms and high doses (> 150 micrograms) blocked Arthus-like reaction induced in guinea-pigs by anti-Forssman antibody. These data establish that soluble forms of MCP are present in human sera that possess cofactor activity and their concentrations, especially the 56 and 47 kDa forms, are increased in sera of cancer patients. High doses of the recombinant soluble forms may be therapeutically useful for suppressing inflammatory responses.

Fc receptors initiate the Arthus reaction: redefining the inflammatory cascade

Antibody-antigen complexes initiate the inflammatory response and are central to the pathogenesis of tissue injury. The classical model for this immunopathological cascade, the Arthus reaction, was reinvestigated with a murine strain deficient in Fc receptor expression. Despite normal inflammatory responses to other stimuli, the inflammatory response to immune complexes was markedly attenuated. These results suggest that immune complex-triggered inflammation is initiated by cell bound Fc receptors and is then amplified by cellular mediators and activated complement. These results redefine the inflammatory cascade and may offer other approaches for the study and treatment of immunological injury.

Neutrophil elicitation in the reverse passive Arthus reaction. Complement-dependent and -independent mast cell involvement

Previous investigations in our laboratory have shown that mast cells play a significant role in the initiation of immune complex-mediated inflammation. Histamine, leukotrienes, and TNF released from mast cells are important mediators of early inflammatory processes. In the peritoneal reverse passive Arthus reaction, we observed a biphasic release of TNF. Mast cells were responsible for the first peak. The complement system is also known to be central to the expression of antibody-induced immune injury. Therefore, in this study, we investigated the significance of activated complement in regulating mast cell stimulation and neutrophil recruitment in the peritoneal reverse passive Arthus reaction. Mast cell degranulation and the release of TNF during the initiation of inflammation were blocked by decomplementation and C5 deficiency. Mast cell degranulation later in the reaction was complement-independent. Therefore, mast cells were activated in vivo in antibody-mediated injury by two different mechanisms, early in the reaction by complement and later by an unknown stimulus. Both mast cells and intact complement were also required for the full expression of neutrophil influx and release of TNF in the later phase. In fact, activated complement and mast cell mediators seemed to be the only factors necessary for the initiation of neutrophil recruitment. The findings significantly contribute to the understanding of the mechanisms involved in the induction of inflammatory processes in immune complex-mediated injury.

Immunostimulatory activity of Picrorhiza kurroa leaf extract

A 50% ethanolic extract of Picrorhiza kurroa Royle ex Benth. (Scrophulariaceae) leaves (PKLE) was found to stimulate the cell-mediated and humoral components of the immune system as well as phagocytosis in experimental animals. PKLE elicited a dose-related increase in SRBC, induced 4 h (early) and 24 h (delayed) hypersensitivity reactions in mice and rats, and horse serum induced Arthus reaction in guinea pigs. It also enhanced the humoral immune responses in mice and rats and phagocytic function of the cells of the reticuloendothelial system in mice. PKLE exhibited no mitogenic activity but augmented the responsiveness of murine splenocytes to T cell mitogens phytohaemagglutinin (PHA) and concanavalin A (Con A) and B cell mitogen lipopolysaccharide (LPS E. coli).

Role of adhesion glycoproteins CD18 and intercellular adhesion molecule-1 in complement-mediated reactions of rabbit skin

1. The role of the adhesion glycoproteins CD18 and intercellular adhesion molecule-1 (ICAM-1) in inflammatory responses produced during a reversed passive Arthus (RPA) reaction and induced by zymosan and zymosan-activated plasma (ZAP) were studied in rabbit skin. 2. Oedema formation and haemorrhage were quantified by measuring accumulation of 125I-albumin and 111In-labelled red blood cells (111In-RBC) respectively. 3. Monoclonal antibody (mAb) R15.7 (anti-CD18), administered intravenously, abolished accumulation of 125I-albumin and 111In-RBC in dermal RPA reactions and in response to locally injected zymosan and ZAP. 4. When administered intravenously, the mAb RR1/1 (anti-ICAM-1) suppressed 125I-albumin and 111In-RBC accumulation in dermal RPA reactions and at sites treated with zymosan and ZAP. 5. Oedema formation in response to platelet-activating factor (PAF) and bradykinin (BK) either in the presence or absence of prostaglandin E2 (PGE2) were not affected by mAb R15.7 or by mAb RR1/1.1.1. 6. We conclude that oedema formation and haemorrhage associated with RPA reactions and in responses to zymosan and ZAP are completely CD18-dependent, and are mediated, at least in part, via ICAM-1. Responses to the neutrophil-independent oedema forming mediators, PAF and BK are not dependent upon CD18 or ICAM-1.

Recombinant soluble human Fc gamma RII: production, characterization, and inhibition of the Arthus reaction

A recombinant soluble form of human Fc gamma RII (rsFc gamma RII) was genetically engineered by the insertion of a termination codon 5' of sequences encoding the transmembrane domain of a human Fc gamma RII cDNA. Chinese hamster ovary cells were transfected with the modified cDNA and the secreted rsFc gamma RII purified from the tissue culture supernatant (to > 95%, assessed by SDS-PAGE) using heat aggregated human immunoglobulin G (IgG) immunoaffinity chromatography. The IgG-purified rsFc gamma RII was relatively homogeneous (approximately 31,000 M(r)) whereas the total unpurified rsFc gamma RII secreted into the tissue culture supernatant was heterogeneous relating to N-linked glycosylation differences. Functional in vitro activity of the rsFc gamma RII was demonstrated by: (a) ability to bind via the Fc portion of human IgG and mouse IgG (IgG2a > IgG1 > > IgG2b); (b) complete inhibition of binding of erythrocytes sensitized with rabbit IgG to membrane-bound Fc gamma RII on K562 cells; and (c) inhibition of the anti-Leu4-induced T cell proliferation assay. Blood clearance and biodistribution studies show the rsFc gamma RII was excreted predominantly through the kidney in a biphasic manner, with an alpha-phase (t1/2 approximately 25 min) and a beta-phase (t1/2 approximately 4.6 h); the kidneys were the only organs noted with tissue-specific accumulation. In vivo, the administration of rsFc gamma RII significantly inhibited the immune complex-mediated inflammatory response induced by the reversed passive Arthus reaction model in rats. There was a specific and dose-dependent relationship between the amount of rsFc gamma RII administered, and the reduction in the size and severity of the macroscopic inflammatory lesion. Histological analysis of the skin showed a diffuse neutrophil infiltrate in both control and rsFc gamma RII-treated rats, however the perivascular infiltrate and the red cell extravasation was less intense in the rsFc gamma RII-treated group. It is likely that complement activation leads to neutrophil chemotaxis, but neutrophil activation via Fc gamma RII, which results in inflammatory mediator release, is inhibited. The data indicate that rsFc gamma RII is a potential therapeutic agent for the treatment of antibody or immune complex-mediated tissue damage.

Locus ceruleus and immunity. III. Compromised immune function (antibody production, hypersensitivity skin reactions and experimental allergic encephalomyelitis) in rats with lesioned locus ceruleus is restored by magnetic fields applied to the brain

This study deals with the relationship between the immunosuppression induced by electrolytic lesions placed into the nucleus locus cerules and the immunopotentiation produced by micromagnets implanted to the parietal area of the skull. The following groups of rats were set up: LC, rats with lesioned locus ceruleus; ShL, sham-lesioned animals bearing non-magnetic beads in the brain parietal region; M, rats with micromagnets of 60 mT influx density in the parietal part of the skull; LCM, animals with impaired locus ceruleus and magnetic beads placed in the parietal area of the skull; and IC, intact control rats. Animals of all groups were tested for plaque-forming cell response, circulating antibodies to sheep red blood cells and bovine serum albumin, Arthus and delayed hypersensitivity skin reactions to bovine serum albumin and old tuberculin, and experimental allergic encephalomyelitis. In LC-rats, humoral and cell-mediated immune reactions were compromised. On the other hand, immune responses in M-rats were significantly potentiated. In LCM-rats, however, the immunosuppression induced by destruction of the locus ceruleus was abrogated by prolonged exposure of the brain parietal region to the magnetic fields, i.e. immune reactivity of LCM-rats was quite similar to that of control IC- and ShL-animals. Several mechanisms may account for the immunomodulating effects produced by lesioning of the locus ceruleus and exposure of the brain to magnetic fields. Noradrenergic, serotoninergic, dopaminergic and peptidergic neurotransmitters, as well as growth hormones and immunopeptides, produced within the central nervous system or elsewhere, may be implicated as necessary for the interactions among the brain, immune apparatus and magnetic fields.

Production of an anti-allergic triterpene bryonolic acid, by plant cell cultures

Cell suspension cultures of Luffa cylindrica, Citrullus lanatus, and related cucurbitaceous plants accumulate large quantities of bryonolic acid (3 beta-hydroxy-D:C-friedoolean-8-en-29-oic acid) [1], an acidic, pentacyclic triterpene found exclusively in the roots of the intact plants. This compound could readily be isolated from cultured cells with CHCl3 and purified simply by recrystallization. Pharmacological tests using mice demonstrated that bryonolic acid or its derivative is active against at least three types of allergies and that its activity could be increased significantly by preparing synthetic derivatives, in particular a potassium salt of its succinate ester. The biosynthesis of bryonolic acid from mevalonic acid via isomultiflorenol has been elucidated by tracer and enzymological experiments using cultured cells of watermelon both in vitro and in vivo. Furthermore, cell fractionation and electron microscopic studies on subcellular structures of luffa cells suggested that minute vesicles originating from elongated, rough endoplasmic reticulum probably play an important role in the transport of bryonolic acid which largely accumulates in the cell wall of cultured cells. The results obtained from the present study indicate that plant cell culture would be useful not only as a biological system for elucidating biosynthetic mechanisms but also as a potential source of new pharmacologically active compounds.

Locus ceruleus and immunity. II. Suppression of experimental allergic encephalomyelitis and hypersensitivity skin reactions in rats with lesioned locus ceruleus

Rats with lesions restricted to the locus ceruleus were tested for immune inflammatory reactions. In these rats, Arthus and delayed skin hypersensitivity reactions to bovine serum albumin and old tuberculin were suppressed. The ablation of locus ceruleus completely inhibited the development of clinical signs of experimental allergic encephalomyelitis, markedly diminished the occurrence and intensity of lesions in the central nervous system, and significantly reduced the production of antibody against the rat brain myelin basic protein. These results establish a link between the locus ceruleus and immune inflammatory reactions in the rat.

Protection of vascular basement membrane and microcirculation from elastase-induced damage with a fluorinated beta-lactam derivative

N-(2-chloromethylphenyl) 3,3-difluoroazetidin-2-one (AA 231-1), a specific suicide-type inhibitor of elastase which is known to suppress the lysis of chromogenic oligopeptides, elastin and elastic fibers, is effective also in preventing the degradation of the vascular basement membrane. The degradation of porcine glomerular basement membrane by purified human leukocyte elastase (HLE), was reduced in proportion of inhibitor dose (8.3 microM for 50% inhibition). It is noteworthy that there was no reduction of the inhibitory effect when the addition of AA 231-1 was delayed for 1 h after the addition of the enzyme to the substrate. In the guinea pig, reduction of the dermal microhemorrhage due to HLE was related to the dose of inhibitor and to its preincubation time with HLE before intradermal injection. The inflammatory hemorrhage associated with the Arthus skin reaction was moderately depressed by AA 231-1 in situ. A part of the vascular permeability induced by HLE also responded to the inhibitor. In spite of the tissular diffusion and the time-dependence parameters which restrict responsiveness of elastase to AA 231-1 in vivo this biochemical compound should be helpful in the study and possibly the cure of vascular injury related to elastase.

[Changes of luminol-dependent chemiluminescence of rabbit peripheral blood leukocytes during incubation with a specific allergen during the development of Arthus phenomenon]

The authors studied luminol-dependent chemiluminescence of rabbit peripheral blood leukocytes during the development of Arthus' phenomenon. Samples with a specific allergen were previously incubated. It was established that in this type of allergic reactions the intensity of leukocyte chemiluminescence was determined by the concentration of the allergen with which they were incubated. Small doses of the allergen stimulate and large doses inhibit it. The inhibition is linked with the direct effect of the allergen on the cells and is not attended with diminution of their viability.