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D Kraft

Publications and source records attributed to D Kraft.

At least 235 records · Page 13Linked to original sources
PubMed1989

Monoclonal antibodies against birch pollen allergens: characterization by immunoblotting and use for single-step affinity purification of the major allergen Bet v I.

Two monoclonal antibodies against birch pollen proteins were produced by immunizing BALB/c mice with birch pollen extract. In immunoblotting experiments, antibody BIP 1 reacted with a 17-kilodalton (kD) protein considered to represent the major birch pollen allergen Bet v I. A second monoclonal antibody, BIP 3, reacted with 3 different birch pollen proteins of molecular weights 32, 36 and 68 kD of which the 36- and 68-kD proteins corresponded to minor allergens of birch pollen. Two-dimensional electrophoresis/immunoblotting experiments revealed that BIP 1 reacted with all Bet v I isoallergens, also identified by human IgE antibodies. Using BIP 1 coupled to Sepharose 4B as reverse immunosorbent, Bet v I was obtained in a single-step procedure and characterized as single band by SDS-PAGE.

Allergens↗
PubMed1989

The influence of renal insufficiency on caesium metabolism in man and rat (with a note on the Cs content of some biological standard materials).

Caesium was measured by instrumental neutron activation analysis in blood plasma and erythrocytes of persons suffering from renal disorders and in age-and sex-matched controls. The disease was at an early stage of development, the patients having creatinine plasma values below 1000 mumol/l. None of them had been dialysed. In a group of 5 patients with plasma creatinine below 250 mumol/l no changes in the blood caesium contents could be observed, but in a group of 17 with plasma creatinine between 250 and 1000 mumol/l the caesium level in the plasma was increased by 70% and in the erythrocytes by 50%, compared to the controls. An effect of renal insufficiency on the caesium metabolism was also observed in rats, in which 5/6-nephrectomy led to increases in the caesium tissue levels (muscle 30%; spleen 25%; pancreas 100%). However, as in the animals the element content in blood plasma and erythrocytes remained unchanged, it is not clear to what extent the nephrectomized rat can be used as a model in the investigation of relations between chronic uraemia and caesium metabolism. It can therefore not yet be decided whether the changes in the blood caesium levels in the patients are due to a decrease in renal excretion or are only a secondary effect of unnoticed changes in dietary habits. The increase in caesium levels suggests, however, that in the first stages of the disease the patients may receive higher radiation doses from the radioisotopes of caesium than the normal population does in the case of environmental or industrial exposure.

Animals↗
PubMed1988

Inhibition of allergic reactions with monoclonal antibody to the high affinity IgE receptor.

A mAb that reacts with the high affinity IgE-R on the rat basophilic leukemia cells (RBL-2H3) was used to inhibit allergic reactions. In vitro, the intact mAb BA3 and its Fab fragment inhibited radiolabeled IgE binding to the RBL-2H3 cells. The mAb binds to the IgE-R with a higher affinity than does IgE. Whereas the intact mAb released histamine from the RBL-2H3 cells, the Fab was inactive. The addition of the Fab fragments to RBL-2H3 inhibited the IgE-mediated histamine release reaction. The Fab fragments also inhibited in vivo passive cutaneous reactions in rats when injected intradermally either before or after IgE. The injection of the mAb Fab i.v. before the injection of the IgE into the skin sites also inhibited reactions, although it was less effective. The results demonstrate that anti-R antibodies can be used as a model for inhibiting immediate hypersensitivity reactions.

Animals↗
PubMed1988

Expression of the VEP13 antigen (CD16) on native human alveolar macrophages and cultured blood monocytes.

Human alveolar macrophages (AM phi) from thirteen patients, who were suffering from various lung diseases were harvested by bronchoalveolar lavage. Peripheral blood monocytes from eight healthy donors were isolated by Ficoll-Hypaque gradient centrifugation and adherence to plastic surface. To detect the VEP13 antigen (CD16) on these cells, a rosette assay employing ox erythrocytes coated by the CrCl3 method with purified VEP13 monoclonal antibody (Eo-VEP13) was used. A mean of 31.3% of freshly isolated AM phi and 3.9% of blood monocytes formed Eo-VEP13 rosettes. Monocytes cultured for 3 or 6 days in the presence of a supernatant from mouse L929 cells, which had been shown previously to improve long-term viability of human monocytes in culture, showed 12.5% and 25.3% Eo-VEP13 rosettes, respectively. No significant increase in VEP13 antigen expression was noted by culturing monocytes without L929 cell supernatant. The factor in L929 supernatant that induces VEP13 antigen expression has not been identified. Tunicamycin at 10 micrograms/ml inhibited significantly VEP13 antigen expression on monocytes. In contrast, IgG rosette formation was not reduced by tunicamycin. Our data show that subpopulations of native human AM phi and peripheral blood monocytes cultured in presence of a supernatant of L929 fibroblasts containing mainly murine CSF may express the CD16 antigen, which is normally found on large granular lymphocytes (LGL). Suppression by tunicamycin indicates that Fc receptor glycosylation takes place during a later differentiation step of mononuclear phagocytes.

Antibodies, Monoclonal↗
PubMed1988

Lack of induction of IgE and IgG antibodies to yeast in humans immunized with recombinant hepatitis B vaccines.

Yeast-derived hepatitis B vaccines (partially purified or highly purified) at different dosages and a plasma-derived hepatitis B vaccine (control) were injected into 50 young volunteers 3 times at monthly intervals. Before and 4 weeks after this series of immunizations, blood samples were drawn and tested for presence of IgE and IgG antibodies against yeast antigens. No rise in IgE antibodies against Saccharomyces cerevisiae antigens nor in IgG antibodies against Candida albicans antigens was found. Together with former clinical results this underlines the experience that type I and type III reactions against putative yeast contaminants apparently play no major role after immunization with recombinant hepatitis B vaccines.

Adult↗
PubMed1988

Isolation and characterization of messenger RNA from male inflorescences and pollen of the white birch (Betula verrucosa).

A glycoprotein with a molecular weight (MW) of 17 kilodaltons (kD), Bet v I, represents the major allergen of the white birch (Betula verrucosa, BV) and plays an important role in tree-pollen-induced type I allergic reactions. In order to characterize the major and also some minor allergens of BV, we investigated the IgE-binding properties of these allergens using immunoblot techniques. Normal and patients' sera were employed for this study. Furthermore, RNA from male inflorescences and from pollen of BV were isolated and purified by affinity chromatography on oligo-dT-cellulose. Poly(A)+-mRNA thus obtained was translated in vitro in a cell-free wheat germ system and the proteins synthesized were separated by SDS-PAGE and transferred to nitrocellulose. The blots were incubated with normal human sera and with sera from patients allergic to birch pollen. Bound IgE antibodies were detected with 125I-labeled anti-IgE. We observed major IgE binding to a protein of an MW of 12.5 kD, and little IgE binding to a 17-kD protein, presumably Bet v I. Comparing the products of in vitro translation from mRNA preparations of mature pollen and of male inflorescences collected in June, October and February, little seasonal variations could be observed. As the in vitro translation system does not glycosylate proteins, our results show that the majority of IgE in patients' sera is not directed against the carbohydrate moieties of these allergens.

Allergens↗
PubMed1987

[Wild silk-induced asthma. A contribution to the knowledge of inhalation allergies caused by wild and tussah silk-filled bed quilts].

In the silk industry occupational IgE-mediated hypersensitivities to different allergens are well known. Since the use of silk waste for the filling of bed quilts a great number of patients suffering especially from silk-asthma could be observed. Immunological investigations showed clearly that in this context sericin and also antigens from an insect of the genus anthrenus in the silk material are of allergenic importance. On the basis of typical case histories from the occupational and private scene the diagnostic difficulties of silk allergy are discussed.

Adult↗
PubMed1987

Rapid reappearance of large granular lymphocytes (LGL) with concomitant reconstitution of natural killer (NK) activity after human bone marrow transplantation (BMT).

The frequency of large granular lymphocytes and their relationship to functional NK-activity as assessed by the capacity to lyse the K562 tumour target was analysed in five allogenic and two autologous human bone marrow transplant recipients. Date revealed: almost identical disappearance and reconstitution of both parameters further indicating that LGL represent effector cells of spontaneous lysis of K562 targets; a long-lasting suppression of the absolute numbers per ml of blood of both LGL and functional NK activity which we believe was not the consequence of reconstitution with immature effector cells but rather reflected immunosuppressive therapy; LGL exhibits the fastest reappearance rate subsequent to total body irradiation of all populations of circulating leucocytes.

Antigens, Surface↗
PubMed1987

Aluminium load in patients with analgesic nephropathy.

It is well-known that plasma aluminium in haemodialysis patients increases with the amount of aluminium hydroxide consumption. In a cross-sectional study at our haemodialysis centre we found that mean plasma aluminium levels are significantly higher in haemodialysis patients with analgesic-associated nephropathy (AAN) than in haemodialysis patients with other kidney diseases (controls) (logarithmic mean +/- SD = 1.93 +/- antilog 0.32 versus 1.21 +/- antilog 0.31 mumol/l; p = 0.001). AAN patients consume a significantly higher amount of aluminium-containing phosphate binders than the controls (21 +/- antilog 0.3 versus 13 +/- antilog 0.4 g/kg body weight/year; p = 0.007). These findings may be explained by the higher incidence of peptic ulcer disease in AAN patients, since hyperacidity decreases the phosphate-binding effect. Analgesic patients also need more aluminium-containing stomach medication than do patients with other kidney diseases (0.21 +/- antilog 1.15 versus 0.03 +/- antilog 0.87 g/kg body weight/year; p = 0.0001). A statistically significant correlation was obtained between bone aluminium and duration of phosphate binder consumption (r = 0.6459; n = 14; p less than 0.05). There was no correlation between plasma aluminium and bone aluminium. Anaemia was more pronounced in the AAN patients than in the others (mean haemoglobin 8.4 +/- 1.9 vs. 9.2 +/- 2.0 g%; p less than 0.02). Dialysis dementia was observed in 4 AAN patients. We conclude that the higher plasma aluminium levels in AAN patients represent a higher aluminium load which may be followed by higher aluminium toxicity.

Aluminum↗
PubMed1986

Abnormal expansions of granular lymphocytes: reactive lymphocytosis or chronic leukemia? Case report and literature review.

A case of chronic lymphoproliferative disorder is presented, wherein a morphologically homogeneous population of lymphoid cells displayed properties similar to those described for large granular lymphocytes (LGL). Besides their LGL-like phenotype (VEP 13+, OKM 1+, OKT 10+ Fc-IgG-receptor+, OKT 3-), the proliferating cells were cytotoxic to NK targets as well as to antibody-coated target cells. Clinically, our patient presented low-grade lymphocytosis, splenomegaly, neutropenia, hyperimmunoglobulinemia and recurrent infections. Based upon this and 32 similar cases reported in the literature, we conclude that lympho-proliferative disorders involving GL encompass a variety of clinical entities, ranging from reactive GL lymphocytoses to overt lymphocytic malignancies.

Adult↗
PubMed1985

Patients with a deficiency of natural killer cell activity lack the VEP13-positive lymphocyte subpopulation.

Many patients with B-type chronic lymphocytic leukemia (CLL) exhibit a profound defect in their natural killer (NK) cell activity, the basis of which is still obscure. Hence, we analyzed the NK cells from peripheral blood samples from 11 patients with CLL for phenotype and function, after removal of the leukemic cells with a monoclonal antibody (BA-1) plus complement. Phenotypic analysis of these nonleukemic cells with monoclonal antibodies (MoAbs) against NK cells revealed that the CLL patients had higher percentages of HNK-1-positive cells (23.5% compared to controls with 14.7%). In contrast, VEP13-positive cells were absent or low in seven patients (0.8% compared to controls with 11.2%) and normal in four patients (10.5%). When testing NK cell activities against K562 or MOLT 4 target cells, patients with no or minimal numbers of VEP13-positive cells were found to be deficient, while patients with normal percentages of VEP13-positive cells had NK cell activity comparable to controls. Isolation by fluorescence-activated cell sorter of HNK-1-positive cells from patients lacking VEP13-positive cells and NK cell activity indicated that the majority of the HNK-1-positive cells in these patients had the large granular lymphocyte morphology that is characteristic of NK cells. Thus, the deficiency of NK cell activity in CLL patients appears to result from the absence of cells carrying the VEP13 marker.

Antibodies, Monoclonal↗
PubMed1985

Expansion of a minor subpopulation of peripheral blood lymphocytes (T8+/Leu 7+) in patients with haemophilia.

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.(ABSTRACT TRUNCATED AT 250 WORDS)

Acquired Immunodeficiency Syndrome↗
PubMed1984

Spaetlese lung.

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Agricultural Workers' Diseases↗
PubMed1984

Selective inhibition of natural killer activity by the monoclonal antibodies OKT10 and VEP10 at the single cell level.

The monoclonal antibodies, VEP10 and OKT10, which have been shown to recognize determinants on human natural killer (NK) cells, inhibit large granular lymphocyte (LGL) NK activity against K562, MOLT4, and CEM tumor target cells in the single cell conjugate agarose assay. Inhibition of NK activity by monoclonal antibodies was expressed independently of effector-target cell binding, as inhibitory activity could be demonstrated when the monoclonal antibodies VEP10 and OKT10 were added to preformed conjugates or to the LGLs and targets prior to the binding event. In addition, this inhibition was exerted on the effector cell and not the target cell since VEP10 and OKT10 did not react with determinants on K562 target cells. Furthermore, the 4F2 monoclonal antibody, which reacted with determinants on the LGL and all of the targets used, effected no inhibition of NK activity. Inhibition of killing by OKT10 and VEP10 was specific to endogenous NK activity since the same antibodies did not inhibit antibody-dependent cellular cytotoxicity (ADCC), mixed lymphocyte-generated NK, or cytotoxic T lymphocyte (CTL) activities.

Antibodies, Monoclonal↗
PubMed1984

The Fc receptor for IgG on human natural killer cells: phenotypic, functional, and comparative studies with monoclonal antibodies.

We compare five monoclonal antibodies ( B73 .1, 3G8 , Leu- 11a , Leu- 11b , and VEP13 ) that react with natural killer (NK) cells and polymorphonuclear cells (PMN). We show that all of these antibodies are directed against and inhibit the functional properties of the receptor for the Fc portion of IgG (FcR). Modulation of the FcR on NK cells after reaction with immune complexes induces the disappearance of the antigen(s) recognized by each of the five antibodies. Conversely, the antibodies block binding of IgG-sensitized erythrocytes to the NK cells and PMN and inhibit their ability to mediate cytotoxicity against antibody-sensitized tumor target cells. By using two-color immunofluorescence techniques, we characterize directly the lymphocyte population recognized by these antibodies and show that it is a homogeneous subset that does not bear markers of either B or T cells, with the exception of the 33,000 dalton antigen characteristic of suppressor/cytotoxic T cells present in 20 to 50% of the cells, and the 45,000 dalton receptor for sheep erythrocytes present on 80 to 90% of the cells. The phenotype of the cells reacting with the monoclonal antibodies corresponds to that of NK cells. Cross-competition experiments indicate that these antibodies detect at least two distinct epitopes on FcR, one ( B73 .1) preferentially expressed on NK cells and one or more ( 3G8 /Leu- 11a /Leu- 11b / VEP13 ) preferentially expressed on PMN. The lack of reactivity of these antibodies with B cells suggests that human B cells bear a different FcR from that on NK cells and PMN.

Antibodies, Monoclonal↗
PubMed1984

The use of VEP13 monoclonal antibody for definition of natural killer cells: spontaneous killer cells directed against fresh human leukaemia cells carry the VEP13 antigen.

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 VEP13 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 analyse 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 beta-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 VEP13 positive fraction. Thus enhanced killing of fresh human leukaemia cells appears to be mediated VEP13 positive NK cells which are distinct from cytotoxic T cells and cytotoxic monocytes.

Antibodies, Monoclonal↗
PubMed1984

The relationship of HNK-1 (Leu 7) and VEP13 antigens on human cells mediating natural killing.

The NK cell associated antigens defined by the two monoclonal antibodies, HNK-1 (anti-Leu 7) and VEP13, 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 M1 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 VEP13+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.

Antibodies, Monoclonal↗