Tezepelumab in a case of severe asthma exacerbation and influenza-pneumonia on VV-ECMO.

We present a case of 43-year-old male patient with broadly by Omalizumab, Mepolizumab and Benralizumab pretreated allergic asthma, who suffered a near fatal exacerbation, triggered by an influenza A infection. Due to massive bronchoconstriction with consecutive hypercapnic ventilatory failure veno-venous ECMO therapy had to be implemented. Hence, guideline directed asthma therapy a substantial bronchodilatation could not be achieved. After administration of a single dose Tezepelumab, a novel TLSP-inhibitor, and otherwise unchanged therapy we documented a significant reduction in intrinsic PEEP measured via a naso-gastric balloon catheter and a narrowing in the expiratory flow curve of the ventilator within 24 hours. The consecutive ventilatory improvement allowed the successful weaning from veno-venous ECMO therapy and invasive ventilation.

Long-term culture of a cell population from Siberian sturgeon (Acipenser baerii) head kidney.

In vitro cultures of native fish cell lines are of great importance, both for basic research and applied science. In particular, there is strong demand for long-term growable cell lines from breeding fish, like sturgeon. Here, we describe the culture of cells from Siberian sturgeon (Acipenser baerii) head kidney. The cells have so far been cultured over a period of 12 months (24 passages). Cytochemical and immunocytochemical examination suggests that, in vitro, the cells exhibit markers that are indicative for different cell types. In particular, fat storing cells (adipocytes) were observed, and the expression of cytokeratins and glial fibrilar acidic protein (GFAP) can be concluded on the basis of immuncytochemical analysis. The observation of different morphologies additionally underlines the heterogeneity of the cell population and matches the typical behaviour of in vitro cultures of stem/progenitor cells. Different applications can be imagined.

Recombinant human erythropoietin induces proliferation and Ca(2+)-influx in specific leukocyte subpopulations of rainbow trout (Oncorhynchus mykiss) blood and head kidney cells.

In mammals, erythropoietin regulates the development and differentiation of erythrocytes. Although hematopoietic cells of bony fish correspond in their ontogeneic development, morphology, and function to their mammalian counterparts, an erythropoietin (EPO)-like molecule has not been identified. In this study we present evidence for a mitogenic response of blood and head kidney leukocytes of rainbow trout after stimulation by recombinant human EPO (rhu EPO). The modulation of cellular activities is accompanied by the induction of DNA-binding activities in nuclear extracts of these cells. In addition, flow cytometric analysis of intracellular Ca2+ concentrations revealed a long-lasting and rhu EPO dose-dependent increase, which was shown to be abrogated by cross-aggregation of surface IgM using anti-trout-IgM monoclonal antibodies (mabs). In flow cytometric dual-labeling experiments using rhu EPO/anti-EPO antiserum and mabs specific for trout leukocyte subpopulations, it was shown that a subpopulation of trout B-cells binds rhu EPO. Moreover, in a modified Ca2+ activation assay, it was demonstrated that this blood B-cell subpopulation is the rhu EPO responder population. In conclusion, the data suggest the existence of EPO-binding receptors in trout that are able to trigger Ca(2+)-independent intracellular signaling in hematopoietic cells of head kidney and Ca(2+)-dependent activation of a subpopulation of B-lymphocytes.

Fine structure of the basilar papilla of the emu: implications for the evolution of avian hair-cell types.

The morphology of the basilar papilla of the emu was investigated quantitatively with light and scanning electron microscopical techniques. The emu is a member of the Paleognathae, a group of flightless birds that represent the most primitive living avian species. The comparison of the emu papilla with that of other, more advanced birds provides insights into the evolution of the avian papilla. The morphology of the emu papilla is that of an unspecialised bird, but shows the full range of features previously shown to be typical for the avian basilar papilla. For example, the orientation of the hair cells' sensitive axes varied in characteristic fashion both along and across the papilla. Many of the quantitative details correlate well with the representation of predominantly low frequencies along the papilla. The most distinctive features were an unusually high density of hair cells and an unusual tallness of the hair-cell bodies. This suggests that the evolution of morphologically very short hair cells, which are a hallmark of avian papillae, is a recent development in evolution. The small degree of differentiation in hair-cell size contrasts with the observation that a significant number of hair cells in the emu lack afferent innervation. It is therefore suggested that the development of functionally different hair-cell types in birds preceded the differentiation into morphologically tall and short hair cells.

Distortion-product otoacoustic emissions and their anaesthesia sensitivity in the European starling and the chicken.

The aim of the present experimental series was to provide further information on the distortion-product otoacoustic emissions (DP) of birds and contribute to a general understanding of DP generation. Basic characteristics of the DP 2f1-f2 and 2f2-f1 were measured in the ear canal of both awake and anaesthetized European Starlings and chickens. The effect of a third suppressive tone and the behaviour of the DP under anaesthesia were also studied. In general, the DP characteristics of both bird species resembled those of lizards and mammals, but first appeared at somewhat higher primary-tone levels. The best frequencies of third tones suppressing 2f1-f2 lay near the first primary tone (f1), but for 2f2-f1, the situation was more complex. Facilitation via a third tone was also seen for both DP, often at levels below those eliciting suppression. The DP 2f1-f2 disappeared completely at the onset of deep anaesthesia and recovered to its original magnitude when the anaesthesia was lightened, sometimes with a considerable delay. The compound action potential (CAP) was somewhat more sensitive to anaesthesia than the DP. Control experiments showed that the anaesthesia effect was not a result of hypoxia. Avian DP at low and intermediate sound levels are thus physiologically-sensitive manifestations of normal hair-cell function that are, in contrast to mammals, also anaesthesia-sensitive.

Electron microscopic study of receptor mediated endocytosis of a monoclonal antibody (RoMo-1) against the surface marker CD 14 of human monocytes.

The internalization of the gold labelled monoclonal antibody RoMo-1 recognizing the CD 14 surface molecule of human monocytes was studied by electron microscopy. Monocyte enriched mononuclear cells (MNC) from the peripheral blood of healthy donors were incubated for 15, 30, 60, and 90 min with gold marked RoMo-1 in Eagle MEM at 37 degrees C. The process of internalization of RoMo-1 occurs as a receptor mediated endocytosis (RME), as described for other ligands.

Histochemical localization of alpha-amylase in the pancreas of pike (Esox lucius) by indirect immunofluorescence.

alpha-amylase is an enzyme, rarely detected histochemically. Only a few examples are known in mammals. A method is described for the histochemical detection of an alpha-amylase in the pancreas of pike using a rabbit antiserum against pike amylase and FITC-labelled anti-rabbit immunoglobulin.

Selective killing of human monocytes by an immunotoxin containing partially denatured mistletoe lectin I.

The in vitro activity of an immunotoxin (IT) prepared by conjugating the monocyte specific RoMo-1 monoclonal antibody and partially inactivated Mistletoe lectin I (dMLI) containing inactivated B chain has been initially characterized. It is shown that while not affecting other mononuclear cells viability, this IT is capable of selectively destroying human monocytes after 24 h exposure thus resulting in the abrogation of monocyte support for PHA reactivity in mononuclear cell preparations. Therefore it seems to be possible to use this non-sugar binding holotoxin for immunotoxin preparation.

Characterization of a monoclonal antibody recognizing a monomorphic determinant of DR antigens.

A monoclonal antibody reacting with human MHC class II molecules was prepared. This antibody, RoDR, is directed against a nonpolymorphic determinant on DR, but not DP or DQ molecules.

Electron microscopic visualization of receptor internalization induced by a monoclonal antibody recognizing the monocyte specific glycoprotein CD 14.

We produced a monoclonal antibody against human monocytes (ROMO 1) which was identified to be directed against the monocyte specific glycoprotein CD 14. For electron microscopic studies, this antibody was labelled with colloidal gold. By using a preembedding technique, we investigated the binding and internalization of gold labelled ROMO 1. The binding is highly specific. No other cells than monocytes bind it. Suspensions of monocytes, prepared from human blood, were incubated for 15 to 90 min with the marked antibody. The cells were labelled on the whole surface. Already after an incubation period of 15 min, the internalization of the antibody receptor-complex is demonstrable. This process is similar to that of receptor-mediated endocytosis (RME), described for different ligands such as cell nutrients, growth factors, hormones, and others.

Human monocyte activation induced by an anti-CD14 monoclonal antibody.

An anti-CD14 mAb RoMo-1 rapidly induces in human monocytes a transient oxidative burst activity as detected by chemiluminescence assay. Pretreatment of these cells with the mAb markedly suppresses the monocyte chemiluminescence response to opsonized zymosan. In addition, the antibody induces a significant increase of IL-1 production and secretion by mononuclear cells, comparable to a similar effect of rIFN-gamma or LPS. Electron microscopy demonstrates internalization of the CD14 molecules after interaction with the mAb in a characteristic receptor-like manner.

[A monoclonal antibody against peripheral human blood monocytes (RoMo-1)]. / Ein monoklonaler Antikörper gegen periphere menschliche Blutmonozyten (RoMo-1).

The monoclonal IgG2a-antibody RoMo-1 binds to peripheral human blood monocytes but does not react with other blood cells, tissue macrophages, HL-60, K 562 or U 937. It seems possible, that the antibody defines an antigen expressed on the premonocytic and monocyte stages of cells from the mononuclear phagocytic system only. The antibody is cytotoxic.

Suppression of GvHR by in vitro allogeneically stimulated lymphocytes: the role of lymphoblasts in the regulation of a primary T-cell response.

Graft versus host reaction (GvHR) induced in 10-day-old F1 mice by in vitro allogeneically or mitogenically stimulated spleen cells is lower than that induced by unstimulated fresh spleen cells. In vitro stimulated lymphoblasts are unable or only slightly able to induce a GvHR. An active suppression by the blasts is not involved. Since lymphoblasts after in vivo stimulation show an increased ability to elicit a GvHR it is concluded that in vitro and in vivo stimulated lymphoblasts have different properties. A different homing cannot be excluded after transfer to the mouse.

[The interleukin 2 receptor. A review of the literature]. / Der IL 2-Rezeptor. Eine Literaturübersicht.

The importance of the receptor ligand system IL 2-receptor and IL 2 for the regulation of the T-cell proliferation was confirmed recently. In this review most important points are discussed as biochemical data, regulation of the expression, monoclonal antibodies, binding behaviour, affinity and activation events. Other activation antigens are also discussed in a short part.

[Inhibitory serum factors in MLR and in PHA-stimulation in sera from normal, allogenic hyperimmunized and transplantation tolerant mice]. / Inhibierende Serumfaktoren in der MLR und bei der PHA-Stimulierung in Seren aus normalen, allogen hyperimmunisierten und transplantationstoleranten Mäusen.

Sera from normal, allogeneically hyperimmunized and transplantation tolerant mice show an inhibitory effect on MLR and PHA stimulation. After gel chromatography these inhibitory factors are preferably found in fraction III for MLR (MW 250-750 KD) and III and IV for PHA stimulation. These factors are not identical with the IL-2 inhibitor. A specific inhibitory component with a MW of about 1000 KD is found in sera from transplantation tolerant mice. This suppressor factor could have a synergistic function in induction of specificity and activity of suppressor cell.

Adoptive transfer of transplantation tolerance in the H-2 compatible mouse system CBA/C3H. Transfer of lymphocyte subpopulations into irradiated and non-irradiated mice.

Transfer of neonatally induced tolerance in the H-2 compatible CBA/C3H strain combination is possible with different efficiency by injection of adherent and non-adherent spleen cells, unseparated spleen cells and lymph node cells from C3H-tolerant CBA mice into sublethal irradiated CBA mice. The most efficient cell populations are adherent spleen cells and lymph node cells. Successful transfer of transplantation tolerance is not possible to non-irradiated mice. The adherent fraction of spleen cells and lymph node cells contains a suppressor cell population responsible for transplantation tolerance against non-H-2 antigens. The induced transplantation tolerance is not due to a chimaeric state of C3H-tolerant CBA mice.

[Mechanisms in the induction and maintenance of transplantation tolerance: an overview]. / Mechanismen bei der Induktion und Erhaltung der Transplantationstoleranz Ein Uberblick.

Transplantation tolerance is used as model for investigation of mechanisms in recognition of "self" and "non-self". The clonal deletion of specific lymphocytes as reason transplantation tolerance is called more and more in question. Active mechanims, as for instance induction and maintenance by suppressor cells are more possible. Suppressor cells may be active not only in inhibition of inductor phase but also in blocking of effector cells. A synergistic effect of blocking factors is supposed too. The thymus plays an important role in induction of transplantation tolerance. Different methods for induction of tolerance are described.

Suppression of GVH reaction in F1 hybrid mice by foetal liver cells.

The effect of foetal liver cells on GVH reaction with the parental lymphocytes in F1 hybrid mice was studied. The GVH reaction was induced in newborn (CBA X C3H)F1 and in 10-day-old (CBA X C57BL/6)F1 hybrid mice. Foetal liver cells did not induce a GVH reaction. The GVH reaction of CBA spleen cells in (CBA X C3H)F1 hybrid mice was demonstrable, although weak. Foetal liver cells suppressed the GVH reaction, in dependence on cell concentration, in (CBA x C3H)F1 but not in (CBA X C57BL/6)F1 hybrid mice. The possibility to induce transplantation tolerance with foetal liver cells is discussed.

[Specificity of cell mediated cytotoxicity. I. Cytotoxic reactions in H-2 system after allogeneic sensitization in vivo]. / Zur Spezifität der zellvermittelten Zytotoxität. I. Zytotoxische Reaktionen im H-2 System nach allogener Immunisierung in vivo. Mit 5 Abbildungen.

Allogeneic sensitization in vivo results in cytotoxic lymphocytes specific in cytotoxic reactions against thymus cells as target cells. Only those targets are destroyed which have common private determinants with the stimulator cell. Target determinants on the K end of the histocompatibility complex are mainly responsible for cell lysis. Alloantibodies block specifically the cytotoxic reaction. First of all blocking activity is directed against the private determinant of the K end. Alloantibodies against public determinants from other H-2 incompatible combinations don't influence the cytotoxic reaction. The blocking antibodies belong mainly to the IgG class but antibodies of the IgM class show a inhibitory activity too.

[Increase of the GvH reaction after alloimmunization. Influence of the serologically defined determinants of the H-2 system]. / Verstärkung der GvH-Reaktion durch Alloimmunisierung. Einfluss der serologisch determinierten Determinanten des H-2 Systems. Mit 1 Abbildung.

GvH reactions were induced in (CBA X C57B1)F1 and (CBA X A)F1 mice with sensitized lymphocytes. Specific sensitization results in an increased GvH reaction, sensitization against third party cells does not influence the GvH reaction. Therefore serologically defined public antigens of the H-2 system play not role in the GvH reaction. The comparison of different numbers of specifically sensitized lymphocytes, lymphocytes sensitized against third party cells, and control lymphocytes for the induction of the GvH reaction leads to the same result.