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The NK cell associated antigens defined by the two monoclonal antibodies, HNK-1 (anti-Leu 7) and VEPI3, were investigated for their mutual expression on peripheral blood lymphocytes of healthy donors. In double labelling experiments only 6 ± 3.9% of peripheral blood lymphocytes (PBL) were found to carry both markers. When VEP13- cells were enriched by rosette formation using VEP13 coated ox red blood cells all the NK activity was recovered in the VEP13- cell preparation, whereas the VEP13- subset was devoid of it, despite of the fact that there was a remainder (7-13%) of HNK-1+ cells. These VEP13+ HNK-1+ cells were found to also bear the T3 antigen but lack the Ml antigen. Thirty-eight to sixty-eight per cent of VEP13+ enriched cell population expressed the HNK-1 antigen too. When these cells were further separated into HNK-1+ and HNK-1- cells by means of the FACS thus yielding the VEP13+ HNK-1 and VEPl3+ HNK-1- subsets, it could be demonstrated that both populations were able to mediate natural killing against K-562 target cells thus indicating existence of an HNK-1- natural killer cell population. Investigating lymphocytes from a patient suffering from a leukaemia in which 75% of cells were of LGL morphology, 32% of cells were found to be HNK-1+ while 76% of cells were shown to bear the VEP13 antigen, thus revealing a similar phenotype as observed in normal individuals. Our results indicate the existence of a HNK-1- VEP13+ natural killer cell population. [ABSTRACT FROM AUTHOR]

In an attempt to produce monoclonal antibodies against human large granular lymphocytes (LGL), the effector cells of natural killer (NK) and killer (K) activity, a monoclonal IgM antibody (VEP10) has been obtained. This antibody is reactive by indirect membrane immunofluorescence (IMPF with 147 ± 8.5% peripheral blood lymphocytes (PBL), with >95% thymocytes and with 25.0±5.0% bone marrow (BM) cells; a stronger expression of VEP10 antigen was found on thymocytes than on PBL and BM cells. Compared to unseparated lymphocytes a higher percentage (58.5± 10.2) of VEP10+ cells could be detected in LGL-enriched cell preparations obtained by Percoll gradient centrifugation. Evidence that the VEP10 antigen is expressed on NK and K cells was provided by depletion of NK/K activity by antibody plus complement treatment of PBL. In addition, VEP10 antigen could be detected on certain human cell lines (Raji, Daudi, Molt4, Yurkat, KG1). The expression of VEP10 antigen on leucocytes could be increased by interferon-α treatment and was also observed on concanavalin A (Con A)- and phytohaemagglutinin (PHA)-activated cells. The IMF distribution of VEP10 antigen on various cell types and successful blocking experiments with OKT10 revealed that both antibodies seem to recognize the same or closely related epitopes on cell membranes. In addition to IMF, a more sensitive assay, rosette formation with VEP 10-coated ox red blood cells, was employed to study VEP10 antigen expression on cells. Rosette formation experiments indicate that this antigen is also present although in lower amounts on IMF-negative cells, e.g. most T, B cells and monocytes. The finding that the expression of the VEP10 antigen increases under the influence of the thymic environment, mitogens or interferon suggests that VEP10 antibody recognizes a molecule involved in the proliferation and differentiation of haemopoietic cells. [ABSTRACT FROM AUTHOR]

Severe itching for unknown reasons has been reported after administration of hydroxyethylstarch (HES) in haemodilution therapy of humans. In skin sections from patients who had received HES for otological reasons HES deposition was found by immunohistochemical methods in keratinocytes, epidermal dendritic cells, endothelial cells and macrophages. The aim of the present investigation was to study the interaction of cultured human monocytes and keratinocytes, normal (HNK) and malignant (KB, A431), with FITC-conjugated HES (200/0.5). Peripheral blood monocytes from healthy donors were isolated by Ficoll-Hypaque gradient centrifugation and adherence to plastic surfaces. Cells were incubated with HES-FITC (1 mg/ml) for 10, 20, 30, 60 and 120 min at 37‡C, washed several times to minimize cell-associated HES-FITC. The uptake of HES-FITC (200/0.5) was detected by fluorescence microscopy and flow cytometry. Monocytes and keratinocytes (HNK, KB, A431) acquired significant amounts of HES-FITC after 120 min. Endocytosis was blunted by the addition of unconjugated HES in ten-fold concentration. At 4‡C, a further inhibition was achieved, indicating an uptake of HES-FITC by monocytes and keratinocytes in vitro. These results indicate that a connection between the storage of HES by keratinocytes and monocytes and the observed itching in patients might be possible. [ABSTRACT FROM AUTHOR]

Seventy-nine patients with acute or former reactions to penicillin were investigated by a benzylpenicilloyl (BPO)-specific RAST and/or by skin tests with penicilloyl-polylysine (PPL), benzylpenicillin and penicilloic acid and the results were correlated with the different clinical pictures. Positive RAST and skin test results could be found in patients with anaphylactic shock, urticaria and serum sickness-like reaction and sometimes in a special group of exanthems, which are characterized by the existence of many different lesions at the same time, therefore called ‘polymorphic exanthems’, and often observed after high-dosage penicillin therapy. In cases of scarlatiniform or morbilliform exanthems no positive results were found. The BPO-specific RAST showed an overall correlation of 95.1% with skin tests using PPL. However, some patients with positive skin tests to benzylpenicillin and penicilloic acid did not have detectable circulating IgE antibodies to BPO. This emphasizes the need for including these antigens in in vitro methods. The RAST was informative even at the time of the allergic reaction or in the first 15 days afterwards and seems to be very valuable for early diagnosis of penicillin allergy especially in cases when many drugs have been given. [ABSTRACT FROM AUTHOR]

Different kinds of IgM antibodies were tested for their activity in antibody-dependent cellular cytotoxity (ADCC): firstly an anti-benzylpenicilloyl (BPO) IgM antibody from immune rabbit serum purified by affinity, ion exchange, and molecular-sieving chromatography, secondly two monoclonal rat anti-BPO IgM antibodies and thirdly a human antidextran antibody prepared from a patient showing restriction of anti-dextran antibodies to the IgM class. Human lymphocytes or purified monocytcs served as effector cells. While the two monoclonal rat and the human IgM antibodies showed no ADCC-mediating capacity, ADCC was induced by the rabbit anti-BPO IgM antibody when high antibody concentrations were used. This activity was abolished by further purification using an anti-rabbit IgG (Fc) immunosorbent. The initially observed activity was shown to be likely due to traces of aggregated anti-BPO IgG, which cannot be detected by the methods commonly used. Preincubation of lymphocytes for 24 hr increased the number of EA (IgM)] rosette forming cells but failed to induce IgM-mediated A DCC. Furthermore, evidence for amplification of low-dose IgG-ADCC by IgM could not be found. [ABSTRACT FROM AUTHOR]

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The article discusses the functions of recombinant allergens in the diagnosis and treatment of atopic allergy. It highlights the allergen-specific monitoring of immunoglobulin antibodies against allergens in childhood including the characterization of cross-reactions in accordance with the molecular structures of allergens. It also discusses several approaches to the production of new molecules for the treatment of birch-pollen allergy.

IgE and IgG antibody responses to birch pollen antigens were studied by means of immunoblotting experiments testing 58 sera from patients with Type I allergy to birch pollen. 56/58 patients showed IgE antibodies react we with Bet v I, a 17 kilodalton (kD) pollen protein. 2D-electrophoresis/immunoblot revealed a heterogeneity of that protein. Ten spots (pH 4.9-5.9) could be detected, presumably representing differentially glycosylated isoallergens. In 33.58 patients, there was no evidence of IgE antibodies directed against allergens other than Bet v I. However, in 25/58 of patients' sera, 11 minor allergens (13, 15, 18, 27, 29, 32, 36, :39, 44, 57, and 68 kD) with individual incidences from 1 .7 % to 17.2 % , were identified. All proteins were also recognized by the patients' IgG antibodies: in the ease of Bet v I recognition was weak, whereas the IgG response to the minor allergens was pronounced. Sera from healthy individuals showed similar IgG antibody responses, but no IgG to the 15, 27, and 29 kD proteins. Our results suggest that IgG directed against minor allergens may junction as trapping antibodies in healthy individuals. Too low or lacking amounts of anti-Bet v I lgG may facilitate an allergic reaction. [ABSTRACT FROM AUTHOR]

IgG, IgM and IgA antibody responses against Micropolyspora faeni (Mf) antigens were studied by means of immunoblotting experiments using 70 sera derived from three groups of farmers, namely patients with extrinsic allergic alveolitis (EAA) due to thermophilic actinomycetes (n = 25), patients without EAA but with hay exposure (n = 14), and patients suspected to have EAA (n = 31), and 27 sera from two groups of control persons (healthy laboratory workers, n = 13; healthy farmers, n = 14). Patients with EAA showed IgG, IgM and IgA antibody responses mainly against the antigens with molecular weights (MW) of 11, 12, 25, 35 and 60 kD ("major antigens"), and in addition, but less often, against six antigens with MW in the range of 15 to 62.5 kD ("minor antigens"). The other two groups of patients and also the exposed control persons showed very similar results; however, the antibody response in healthy farmers was substantially weaker in comparison to the three groups of patients and was almost limited to the major antigens with MW 11, 25 and 60 kD. Although patients with proven EAA had higher amounts of antibodies, there was no correlation between this antibody response and the onset of disease. The results indicate the necessity of including at least the major antigens with MW of 11, 25 and 60 kD in all extracts used for in vitro diagnosis of Mf-induced EAA. [ABSTRACT FROM AUTHOR]

The red cell-linked antigen-antiglobulin reaction (RCLAAR) with stearoyldextran-coated erythrocytes was used to characterize the immunoglobulin (Ig) classes and IgG subclasses of dextran reactive antibodies (DRA) in 27 dextran reactors (DR) and 96 non reactors (DNR). High litres of dextran reactive IgG were regularly found in sera of patients with severe dextran-induced an anaphylactoid/anaphylactic reactions (DIAR) prior to the infusion. In four lethal cases IgG antibodies were found to be in the highest titre range of 16,384 to 32,768. In addition, high IgA and IgM litres were also found in severe DIAR. DNR had much lower titles of dextran reactive antibodies of IgG, IgM and IgA classes and IgD antibody was absent in both groups. Dextran reactive IgE antibodies were not demonstrable in DR. Dextran reactive IgG2, IgG3, IgG4 and IgGl (indirect measurement) were, demonstrated in both DR and DNR. Dextran infusion caused variable neutralization in all Ig classes and IgG subclasses, but the contribution of IgG2 was considered most important because of its high litres and most pronounced neutralization in severe DIAR. It is concluded that DRA mainly of the IgG class, play a critical pathogenic role in the induction of severe DIAR, which accordingly is classified as immune complex (type III) anaphylaxis. The method of RCLAAR allows to delineate a risk group of about 2% of potential reactors. [ABSTRACT FROM AUTHOR]

In order to obtain information about the clinical course and immunological background of possible allergic reactions due to penicillin-containing food, nine volunteers with penicillin allergy proved by case history, positive skin tests and/or positive penicilloyl-specific RAST were exposed to penicillin-contaminated pork. For this purpose a farm pig from an inbred strain received "therapeutic" doses of benzyl procain penicillin before being slaughtered. Meat samples were taken from muscle tissues, kidney and liver and analyzed by diffusion and extraction methods. Very small amounts of penicillin were detectable in muscle tissue, whereas kidney material contained up to five times as much (0.12 mcg/g). Except two cases which reacted with itchy sensations after ingestion of penicillin contaminated meat "a la tartare", all probands were clinically free of symptoms. Assaying penicilloyl-specific IgE antibodies by RAST during the trial, a tendency to increased levels in the serum after 2 and 24 b was noted, whereas the titers of BPO-specific IgG antibodies measured by the red cell-linked antigen-antiglobulin reaction (RCLAAR) remained unchanged. It is concluded from this study that small and hidden amounts of penicillin and its derivatives in food seldom induce anaphylactic reactions in penicillin allergic patients. [ABSTRACT FROM AUTHOR]

The plant Solanum malacoxylon (S.M.) is known to cause severe soft tissue calcifications in cattle and sheep and has recently become of special, interest since it exerts biological actions which resemble those of vitamin D. In order to investigate whether S.M. is capable to improve the rachitic bone changes in vitamin d and phosphate deficient rats, a watery extract of 50, 100 and 200 mg S.M. was fed daily to these animals over a period of 10 days. The width of epiphyseal plates was compared after that time with those of rats treated with 0, 0.225, 0.45 and 0.9 IU of vitamin D daily. There was a dose related curative effect of S.M. on the epiphyseal lesions very similar to that of vitamin D. The hypercalcemic and hyperphosphatemic effect of S.M. was identical to that of vitamin D. The 25-hydroxy-vitamin D serum levels remained almost undetectable, in the S.M. treated rats as well as in the vitamin D treated animals. [ABSTRACT FROM AUTHOR]

The relative vitamin D resistance in patients with chronic renal failure and in those with hypoparathyroidism is due to an impairment of 1-hydroxylation of cholecalciferol. 5,6-trans-25OHCC, which has a similar steric configuration as 1,25(OH)CC was examined at a daily dose of 18,000 IU for 14 days in both diseases. Intestinal calcium absorption as well as serum calcium level could be normalized in most patients with hypoparathyroidism. The improvement was less in patients with chronic renal failure, suggesting an additional depressing influence of uremia on calcium metabolism. [ABSTRACT FROM AUTHOR]

Immunological analysis of peripheral blood mononuclear cells (PBM) was performed in 20 patients with haemophilia A or B. One of the patients had never received clotting factor substitution in his life. Six different sources of lyophilized clotting factor were used for the other patients, but every given patient received factor from one source, exclusively. None of the patients exhibited lymphadenopathy and only one suffered from local bacterial infection. Mononuclear cell counts were within the normal range and mitogen stimulation with phythaemagglutinin (PHA) and concanavalin A (Con A) was found normal in all but two patients. Ratios of helper and suppressor cells (T4/T8) were below 1.0 in 10 of the patients. Some of these patients had a relative increase of T8+ cells and at the same time of Leu 7+ (natural killer (NK)/suppressor) cells. Double-marker analysis revealed that the subpopulation of cells expressing both the T8 and the Leu 7 antigen, which on the average accounted for 2 1% of the mononuclear cells in controls, was increased 4.5 fold (9.1%) in haemophilia patients. One patient exhibited 37.8% T8+/Leu 7+ double-marker cells. VEP13+ cells (active NK cells) were decreased below the normal range in 11 of the patients. Abnormal values for lymphocyte subsets were found in every treatment group. The patient who had never received any clotting factor exhibited normal values in all respects. In an additional set of patients, those with increased percentage of T8+/Leu 7+ cells exhibited decreased NK cell activity indicating that the T8+/Leu 7+ cells are not active NK cells. The expanded subpopulations of T8+/Leu 7+ double-marker cells described in this report might represent an important immunoregulatory subset, and deserves further study in patients with immunodeficiency. Seropositivity for human T-cell leukaemia virus (HTLV-III) was detected in six of 18 sera tested. The presence of antibody, however, did not correlate with any of the immunological abnormalities, including the expanded T8+/Leu 7+ double-marker cells. [ABSTRACT FROM AUTHOR]

VEP13, an IgM monoclonal antibody (MoAb). produced against human large granular lymphocytes, is able to deplete natural killer (NK) cell activity in complement-dependent lysis. Here we report that VEPI3 also reacts with the majority of interferon (IFN) activated NK cells. By contrast cytotoxic activity of unstimulated monocytes and cytotoxic T cells directed against allogeneic lymphocytes were unaffected by VEP13 plus complement treatment. Thus among the major types of cytotoxic cells VEP13 selectively reacts with NK cells and hence can be employed to identify these cells. We therefore used VEP13 in complement-dependent lysis and FACS separation to ansilyse NK cells involved in enhanced killing of fresh leukaemia cells. Spontaneous cell-mediated lysis of human leukaemia cells was enhanced in two ways: (a)effector cells were pre-treated with β-IFN and (b) leukaemia cells were pre-treated with a pulse of actinomycin D. In complement dependent lysis VEP13 removed all NK. cell activity of IFN activated PBM against untreated and against ActD pre-treated leukaemia cells. FACS separation of VEP13 positive cells further supported this finding, in that all activity of IFN activated NK cells against actinomycin D pre-treated targets was found in the VEPI3 positive fraction. Thus enhanced killing of fresh human leukaemia cells appears to be mediated VEPI3 positive NK cells which are distinct from cytotoxic T cells and cytotoxic monocytes. [ABSTRACT FROM AUTHOR]

Background and Objective. The mechanisms operative in specific immunotherapy (SIT) of Type I allergy are not completely understood. In the present study we evaluated immunological changes during SIT in pollinosis. Method. Eight patients suffering from pollinosis (monosensitized to grass pollen) were treated with conventional SIT. All subjects had IgE specific for Ph1 p 1, a major allergen of timothy grass. In vitro changes in the immunological reactivity to grass pollen extract and to recombinant Ph1 p 1 were evaluated. Subjects were examined at three occasions: before, after 3 months and after 1 year of SIT. Results. Serological analysis revealed a marked increase of grass pollen- and Ph1 p 1-specific IgG, titres of specific IgE did not change significantly. Lymphoproliferative responses to grass pollen extract and rPh1 p 1 were reduced already after 3 months of treatment. Accordingly, the cloning efficiency for Ph1 p 1-specific T-cell clones (TCC) dropped markedly in all patients. The majority of allergen-specific TCC raised before SIT revealed a TH2-like pattern of cytokine production. TCC established after SIT revealed TH1 characteristics. This shift was due to a decrease in IL-4 rather than an increase of IFN-production by T cells. Investigations of the epitopes recognized by T cells before and after SIT did not reveal the outgrowth of new ('protecting') specificities. We could not observe induction of allergen-specific CD8+ lymphocytes (supressor cells). Conclusion Our data indicate that &mdash on the level of TH lymphocytes — SIT induces tolerance to the allergen and a modulation of the cytokine pattern produced in response to allergen stimulation. [ABSTRACT FROM AUTHOR]

Background Allergic conjunctivitis is a common symptom amongst Type I (IgE-mediated) allergic diseases; and most frequently seen as rhinoconjunctivitis. However, the site of production and the significance of allergen specific IgE needs further elucidation. Objective We investigated whether the presence of IgE in tears of grass pollen allergic patients correlated with disease and clinical symptoms, whether the IgE binding pattern to the different grass pollen antigens was different in sera and tears, and whether IgA antibodies to grass pollen allergens were present in tears. Finally, we looked whether specific IgE was produced locally or was exudated from serum. Methods Sera from 44 grass pollen allergic patients suffering from either allergic rhinitis (n =11) or allergic rhinoconjunctivitis (n = 33) and from healthy controls (n =7) were used for the experiments. Binding of specific IgE and IgA antibodies to the different groups of grass pollen allergens (Phleum pratense) was evaluated by means of immunoblotting. Results Specific IgE was detected in sera as well as in tears of allergic patients, whereby tear-derived allergen-specific IgE exerted similar specificities to the corresponding IgE from serum. The correlation between symptoms of ocular allergy and the presence of allergen-specific IgE in tears was highly significant (P = 0.0001). In contrast, only a poor correlation was found between specific and/or total IgE in sera and the manifestation of ocular allergy (P = 0.73). Conclusion Allergen-specific IgE antibodies in tears seem to be produced locally rather than exsudated from serum. IgE in tears seems to be responsible for allergic conjunctivitis. IgA in tears cannot exert a protective function since the IgA antibodies recognize different antigens in a grass pollen (Phleum pratense) extract than IgE antibodies. The highly significant correlation between allergic conjunctivitis and the presence of specific tear IgE emphasizes the diagnostic value of immunoblots with tear IgE, especially in cases in which serum provides inconclusive results. [ABSTRACT FROM AUTHOR]

Background Type I allergy represents a severe health problem in industrialized countries where up to 20% of the population suffer from allergic rhinitis, conjunctivitis and allergic asthma bronchiale and in severe cases from anaphylaxis, leading to death. Objective The aim of this study was to evaluate recombinant Bet v I, the major birch pollen allergen for in vivo and in vitro diagnosis of birch pollen allergy. Methods A group of 51 birch pollen allergic patients and eight non-allergic control individuals were tested for birch pollen allergy by skin-prick and intradermal testing, comparing commercial birch pollen extracts with recombinant Bet v I. Quantitative and qualitative serological testing was done with natural and recombinant allergens by radioallergosorbent test (RAST), enzyme-linked immunosorbent assay (ELISA) and immunoblotting. Results Recombinant Bet v I allowed accurate in vivo and in vitro diagnosis of tree pollen allergy in 49/51 patients tested. No false positive results were obtained in any in vitro assay system (ELISA, Westernblot) or by skin testing (skin-prick, intradermal test) with recombinant Bet v I. Conclusion Our results document that recombinant Bet v I produced in bacterial expression systems allows accurate in vitro and in vivo diagnosis of birch pollen allergy in < 95% of birch pollen allergic patients. [ABSTRACT FROM AUTHOR]

Copyright of Archiv für Dermatologische Forschung is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The application of disodium dichloromethylene diphosphonate (ClMDP), a diphosphonate which is known to inhibit bone formation and bone destruction leads to changes in the metabolism of 25-Hydroxycholecalciferol. The concentration of the tissue active form of vitamin D, i.e. 1,25-Dihydroxycholecalciferol, was found to be markedly diminished in blood serum, kidney and intestine. It is discussed whether this finding is due to a direct effect of ClMDP on 25-Hydroxycholecalciferol-1-hydroxylase in the kidney or indirectly caused by a disturbance of the regulation of 1,25-Dihydroxycholecalciferol production. [ABSTRACT FROM AUTHOR]