In vivo imaging of inflammation using an aptamer inhibitor of human neutrophil elastase.

BACKGROUND: We previously reported the isolation of aptamer irreversible inhibitors of human neutrophil elastase. We now report on the application of aptamer technology to the field of diagnostic imaging. RESULTS: The enzyme elastase has been reported to bind to the surface of activated neutrophils. Using a fluorescent flow cytometry assay, we showed that an aptamer inhibitor of elastase also binds preferentially to activated neutrophils. We then tested the ability of the aptamer to image inflammation in vivo in a rat reverse passive Arthus reaction model. The aptamer achieved a peak target-to-background (T/B) ratio of 4.3 +/- 0.6 in 2 hours. IgG, which is used clinically to image inflammation, took a longer time to achieve a lower T/B: 3.1 +/- 0.1 at 3 hours. The difference in T/B values is due to the faster clearance of the aptamer signal from the blood pool. CONCLUSIONS: It is feasible to apply aptamer ligands for use in diagnostic imaging, where they may offer significant advantages over monoclonal antibodies and other reagents.

A rapid and reliable in vivo method for anti-GPLA (class I and class II antigens) antibody titration and GPLA typing.

A reverse Arthus reaction (RAR) may be successfully used in guinea pigs to detect histocompatibility alloantigens of the GPLA type. Epidermal cells carry class I GPLA antigens, and Langerhans cells also bear class II alloantigens. It is therefore possible to elicit an RAR by intradermal injection of relevant alloimmune sera in the skin of guinea pigs of known GPLA haplotype. RAR is detected by increased vascular permeability due to IgG1 antibody and hemorrhage due to IgG2 antibody. Compared with an in vitro protein A-rosetting method RAR is easier and quicker. It proved more sensitive for class II antigens in which Langerhans cells are the target for anti-class II antibody and rather less sensitive for class I antigens. RAR is a convenient method for following the course of GPLA alloimmunization, allowing titration of antibodies against both classes of antigen. It may also be used to type guinea pigs of unknown GPLA haplotype.

[Necrotizing enteritis due to hypersensitivity reaction (similar to Arthus phenomenon)]. / Enterite necrotizzante da reazione di ipersensibilità (Arthus simile).

Necrotizing enteritis is a clinico-pathological entity, marked by segmentary necrosis of jejunum and ileum, variously extended, and is a rather rare picture, the etiopathogenesis of which is prevailingly supported by troubles in the intestinal circulation or by intestinal locations of reactions of hypersensitivity (Arthus-similar allergic reaction). The authors start from a case they had the opportunity to observe and successfully surgically treated, and discuss its etiopathogenetic and therapeutical implications in the light of an up-to-date reviewing of the literature thereabout.

A new reliable method for evaluation of foot pad swelling as an experimental in vivo immune phenomenon.

Weight determination of replicas of the feet from living mice is described as a new method for evaluating the degree of the experimentally induced foot pad swelling in immunized mice. The new method gives objective, well documentable results and offers advantage to the commonly used assay with the dial calliper gauge when there is need for a good documentation or whenever there is a large number of animals to be tested within a narrow time margin.

Acute eosinophilic pneumonia induced by minocycline: prominent Kerley B lines as a feature of positive re-challenge test.

We report herein a case of acute eosinophilic pneumonia induced by minocycline, confirmed by TBLB and re-challenge test. Re-challenge test suggested that Arthus-type reaction was pathognomonic, and prominent Kerley B lines represented a local hypersensitivity reaction in this patient.

[A case report of bird fancier's lung (author's transl)]. / Ein kasuistischer Beitrag zur allergischen Alveolitis (Vogelhalterlunge)

By a case of bird fancier's lung proved serologically by precipitin tests the importance of a detailed case history is being stressed since there is an increased frequency of exogenous allergic alveolitis. The paper shall contribute to an early diagnosis to avoid irreversible professional and non-professional damages. For all cases of manifest disease constistent avoidance of allergens is demanded.

Skin test for coeliac disease using a subfraction of gluten.

Gluten and various of its fractions and subfractions have been used for intradermal testing in 10 patients with coeliac disease and in 20 healthy control subjects. All the coeliac patients gave positive Arthus-type reactions (type III) to the subfractions of gluten, whereas all the control subjects were negative. The subfraction B2 evoked strong reactions in almost all the coeliac subjects. If tests with larger series confirm the present results, skin testing with B2 may prove to be a useful screening test for coeliac disease. As B2 has already been found to stimulate the lymphocytes of coeliac patients, the present findings are also of interest in relation to the pathogenesis of coeliac disease.

[Immune complexes and their pathogenetic significance]. / Immunkomplexe und ihre pathogenetische Bedeutung.

The specific binding of antigens by antibodies leads to the development of antigen-antibody-complexes. Apart from the connected with this and desirable immunological protection immune complexes, however, may also have an pathogenic effect on certain conditions (e. g. transmission of the capacity of phagocytosis), depositing themselves in the vascular regions concerned, activating complement and after binding to cell membranes causing the release of unspecific mediators. Finally these lead through increased vascular permeability, local ischaemia and hyperaemia, respectively, and the release of proteolytic enzymes to a lesion of the tissues. In a series of in most cases chronic inflammatory diseases depositions of immune complexes may be proved in the tissues concerned. However, it is difficult to establish exactly in the individual case, whether they considerably participated in the development of the clinical picture. By analogies to experimentally produced immune complex diseases at least some entities of diseases (e. g. lupus erythematodes disseminatus) or defined local alterations of the tissues (e. g. glomerulonephritis of immune complex type) may be defined pathogenetically.

Hypersensitivity pneumonitis.

Hypersensitivity pneumonitis, a disease caused by repetitive inhalation of nonviable organic dust, is increasingly recognized as a cause of acute and chronic lung disease in both children and adults. Twenty-one of 32 children and adults who went on a hay ride in Arkansas developed this disease. These cases are reported. The clinical manifestations, pathology, differential diagnosis, treatment, and immunologic aspects of the disease are reviewed.

[Classification, diagnosis, and therapy of immunological aspects of disease according to reaction types]. / Einteilung, Diagnostik und Therapie immunologischer Krankheitsbilder nach Reaktionstypen

The classical division of the immune reactions into an immediate humoral type and a cellular late type is left in favour of a classification in 4 forms of reaction according to Gell and Coombs. This classification allows of a by far more reasonable coordination of the diagnostic measures as well as aimed therapeutic conclusions. In detail are differed: type I as anaphylaxis and reagin type (mediator-substance-type), example-anaphylactic shock and asthma; type II as cytotoxic type (cytotoxic antibodies), example-Coombs-positive haemolytic anaemia; type III as immune complex type, examples-serum disease, Arthus-reaction, glomerulonephritis; type IV as type of the cellular immune reactions. Combinations and transitions are possible in the same way as a further sub-classification of the types. It is demonstrated as by the combination of in-vitro-tests, skin tests and, perhaps, bioptic investigations the type is to be determined as far as possible. Only this allows an aimed and reasonable therapy.

[Diarrhea in immunopathies]. / Durchfälle bei Immunopathien

The main symptom in immunologic diseases of the gut is diarrhea. This is true for heterosensitization as well as for autosensitization, for local as well as for generalized diseases. Since the immunopathogenetic mechanism is connected with the presence of the antigen, the manifestation is depending on its local and temporal persistence. Elimination of the antigenic factor terminates the diarrhea. In autosensitization this is not possible; therefore an antiphlogistic and immunosuppressive therapy is necessary.

In vivo responses to inhaled proteins. III. Inhibition of experimental immune complex pneumonitis after suppression of peripheral blood lymphocytes.

We have previously shown that inhaled Con A has a powerful enhancing effect on the formation of immune complexes between an inhaled antigen and circulating antibody. Immunohistochemical staining has demonstrated such complexes, together with host complement, in close association with foci of necrotizing destruction of the pulmonary parenchyma. We have postulated that Con A promotes immune complex formation indirectly through polyclonal activation of lymphocytes in the lung. In this paper we test this hypothesis in animals rendered unresponsive to Con A stimulation in vivo by i.v. administration of cholera toxin (CT). Such treatment raised the levels of cAMP in peripheral blood lymphocytes and inhibited their proliferative response to Con A in vitro. CT administration further blocked the local inflammatory response to intradermal injections of Con A, as well as the cell-mediated immune response to intradermal injections of BSA. Although CT failed to block the immune complex-mediated Arthus vasculitis in the skin, it did block production of immune complex pulmonary injury by antigen/mitogen aerosols, as did decomplementation with purified cobra venom factor. These findings support the hypothesis that polyclonal activation of pulmonary lymphocytes promotes immune complex-type alveolitis, possibly by facilitating interactions between humoral antibody and intra-alveolar antigen.

Analysis of vascular lesions in murine SLE. I. Association with serologic abnormalities.

In murine SLE, two different vascular lesions can develop. A necrotizing polyarteritis (NPA), exclusively found in MRL/I mice, is characterized by a dense infiltration of PMN and fibrinoid necrosis of the arterial wall. The second, a degenerative vascular lesion, occurs in a low incidence in all SLE mice, except the (NZW X BXSB)F1 (WBF1) male, in which its incidence is 100%. This lesion shows subendothelial deposits of immunoglobulins with minimal or no inflammatory or proliferative reaction. This degenerative vascular disease (DVD) is predominantly localized in the coronary arteries and is highly correlated with myocardial infarction. Serologic analysis revealed that NPA in MRL/I mice was associated with relatively late development of high levels of autoantibodies and circulating immune complexes; DVD in WBF1 mice was associated with an early onset of autoantibody production of a low magnitude that gave rise to a persistent low level of circulating immune complexes. Characterization of circulating immune complexes in MRL/I mice showed these complexes were mainly of intermediate size (7S-19S) and contained predominantly anti-DNA antibodies. In WBF1 mice, complexes were barely detectable and contained mostly anti-gp70 antibodies. Elution of kidneys showed that the major antibody deposited in MRL/I mice has an anti-DNA specificity, whereas in WBF1 animals, the major antibody was anti-gp70. Furthermore, a 10 times greater amount of immunoglobulins could be eluted from WBF1 hearts with DVD than from MRL/I and BXSB hearts. Additionally, we found that the lack of an inflammatory reaction in DVD was not because of a preferential deposition of noncomplement-fixing IgG1 antibodies nor could it be related to a defective inflammatory response, because WBF1 mice had an undiminished reverse passive Arthus reaction throughout their lives. It is concluded that NPA develops secondary to high levels of autoantibodies with a concomitant rise in immune complexes, whereas DVD is associated with sustained low levels of circulating immune complexes.