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J Wypych

Publications and source records attributed to J Wypych.

At least 37 records · Page 2Linked to original sources
PubMed1990

Identification, purification, and biological characterization of hematopoietic stem cell factor from buffalo rat liver--conditioned medium.

We have identified a novel growth factor, stem cell factor (SCF), for primitive hematopoietic progenitors based on its activity on bone marrow cells derived from mice treated with 5-fluorouracil. The protein was isolated from the medium conditioned by Buffalo rat liver cells. It is heavily glycosylated, with both N-linked and O-linked carbohydrate. Amino acid sequence following removal of N-terminal pyroglutamate is presented. The protein has potent synergistic activities in semisolid bone marrow cultures in conjunction with colony-stimulating factors. It is also a growth factor for mast cells. In two companion papers, we present the sequences of partial SCF cDNAs, identify SCF as a c-kit ligand, and map the SCF gene to the Sl locus of the mouse.

Amino Acid Sequence↗
PubMed1990

Phospholipase A2 in venom extracts from honey bees (Apis mellifera L.) of different ages.

We measured phospholipase A2 activity in the venom of worker honey bees (Apis mellifera L.) of known ages using chemical (titrimetric) and radioallergosorbent methods. The two techniques give similar results. Low levels of phospholipase A2 are present in the venom system at the time of eclosion. Phospholipase A2 activity in the venom increases steadily through the 10 days after eclosion. Maximal phospholipase A2 levels (about 40 micrograms phospholipase A2/venom sac) are maintained through the rest of the life of a worker bee in summer.

Aging↗
PubMed1988

Hepatitis B vaccine produced in yeast.

A gene encoding the 226 amino acid hepatitis B surface antigen (HBsAg), subtype adw, was cloned into a generalized vector for the expression of heterologous genes in Saccharomyces cerevisiae. The 5' end of the genomic HBsAg gene was replaced with a chemically synthesized DNA segment that conserved the amino acid sequence of the protein but utilized DNA sequences that optimize translation initiation in yeast. High-cell-density fermentations of laboratory strains of Saccharomyces cerevisiae have been developed in which HBsAg production increases linearly with respect to cell mass. The HBsAg is present as a lipoprotein particle in cell lysates and has been purified to homogeneity. The evidence presented indicates that the HBsAg particles may be formed during lysis of the yeast cells. The purified HBsAg particles have a morphology similar to that of the 22 nm particles present in the serum of human chronic carriers of hepatitis B. The reactivity of the yeast-derived HBsAg particles with a series of monoclonal antibodies is essentially identical to that of human plasma HBsAg. By this analysis, therefore, the structure of the HBsAg protein is similar in yeast and in human particles. The purified yeast HBsAg particles were formulated with alum adjuvant and subsequently were shown to confer immunity in chimpanzees to challenge with two heterologous serotypes (adr, ayw) of hepatitis B virus.

Animals↗
PubMed1988

Effects of hematopoietin-1 and interleukin 1 activities on early hematopoietic cells of the bone marrow.

Hematopoietin-1 (H-1) was purified from the human cell line 5637 and two amino acid sequences were observed in the preparation. One sequence was identical to that of interleukin 1 alpha (IL 1 alpha) and the other to that of IL 1 beta. The action of recombinant IL 1 alpha and other hematopoietic growth factors was studied using (a) a high proliferative potential colony-forming cell assay that uses primitive hematopoietic precursors from bone marrow, and (b) a spleen colony-forming unit assay. The results indicate that the IL 1 alpha target cell population is different than the target cell populations of IL 3, granulocyte-macrophage colony-stimulating factor; that IL 1 alpha in combination with mononuclear phagocyte colony-stimulating factor provides a proliferative stimulus; and that IL 1 alpha has at least a survival-enhancing and possibly proliferation-inducing effect on primitive hematopoietic stem cells.

Amino Acid Sequence↗
PubMed1987

Recombinant-DNA-derived bovine growth hormone from Escherichia coli. 1. Demonstration that the hormone is expressed in reduced form, and isolation of the hormone in oxidized, native form.

The isolation of bacterially synthesized, recombinant-DNA-derived, bovine growth hormone (r-bGH) with native structure is described. The r-bGH is found in insoluble form, in a pellet fraction, after cell breakage and centrifugation. Cell envelope components (protein, lipid, endotoxin) and nucleic acids are selectively removed from the pellet fraction by an EDTA/lysozyme/deoxycholate extraction. We demonstrate that the r-bGH is largely reduced until solubilized using 6 M guanidine/HCl. Air oxidation is then carried out, in the presence of the guanidine/HCl. The oxidation results in a mixture of about one-third disulfide-linked oligomers and two-thirds oxidized monomer. The latter may include some incorrectly oxidized material, but appears to be mostly correctly oxidized. The oxidized monomer is isolated by gel filtration in the presence of guanidine/HCl. Subsequent guanidine/HCl removal leads to refolded, oxidized r-bGH. All steps in the procedure, in particular the oxidation and refolding steps, can be carried out at relatively high protein concentrations.

Animals↗
PubMed1987

Recombinant-DNA-derived bovine growth hormone from Escherichia coli. 2. Biochemical, biophysical, immunological and biological comparison with the pituitary hormone.

Bacterially synthesized, recombinant-DNA-derived bovine growth hormone (r-bGH), prepared as described in the preceding paper in this journal, has been characterized in comparison with pituitary bovine growth hormone (pit-bGH). The characterization criteria include sodium dodecyl sulfate/polyacrylamide gel electrophoresis, automated N-terminal sequence analysis, amino acid composition, isoelectric focusing, reverse-phase high-performance liquid chromatography, ultraviolet absorbance, analysis for free protein thiol, sizing by gel filtration, circular dichroism, radioimmunoassay and biological activity in the hypophysectomized rat weight-gain assay. In every respect the r-bGH appears to be virtually identical to pit-bGH.

Amino Acids↗
PubMed1985

Heparin-induced thrombocytopenia and thrombosis: detection and specificity of a platelet-aggregating IgG.

A 46-year-old female who died as a result of thrombocytopenia associated with multiple arterial occlusions and septicemia while on heparin therapy was found to have a platelet-aggregating factor present in several plasma samples and in a sample of serum. This factor was subsequently shown to be an IgG with aggregating properties toward normal platelets that were enhanced by, but not dependent on, the presence of heparin. Further studies showed that heparin was unlikely to have acted as a hapten in initiating the IgG production but that its role was significant in aggravating the ensuing arterial thrombosis. The necessity of substitution of heparin with alternative anticoagulant/antithrombotic therapy to avoid the worst sequelae of this potentially catastrophic syndrome is discussed.

Blood Coagulation Factors↗
PubMed1984

Application of recombinant DNA technologies to studies on chicken growth hormone.

Messenger RNA isolated from chicken pituitaries was used to construct a chicken pituitary cDNA library. A chicken growth hormone cDNA clone was isolated using 32P-labeled mammalian growth hormone cDNA probes. The amino acid sequence (derived from the DNA sequence) of the mature form of chicken growth hormone shows 77% homology with that of bovine growth hormone. The chicken growth hormone cDNA clone was used to generate a vector capable of producing chicken growth hormone in Escherichia coli. The recombinant E. coli-derived chicken growth hormone was similar to pituitary chicken growth hormone in several biochemical and immunological properties. The recombinant-derived hormone has been used to establish a sensitive radioimmunoassay for growth hormone determinations made from chicken sera. The chicken growth hormone gene has also been introduced into a retroviral vector capable of establishing productive infections of chicken cells both in in vitro and in vivo. The resulting infections are accompanied by the production of radioimmunoassay-detectable growth hormone. The concentrations of growth hormone in sera of Leghorn chickens infected with the recombinant retrovirus are three- to tenfold higher than in control animals.

Amino Acid Sequence↗
PubMed1982

Comparison of the allergenicity and antigenicity of yellow jacket and hornet venoms.

The immunologic properties of yellow jacket and hornet venoms were compared by measuring their reaction with rabbit antisera and human IgE and IgG antibodies. Anti-hornet venom rabbit serum showed precipitin bands unique to hornet venom and several bands crossreacting with yellow jacket venom. Anti-yellow jacket venom rabbit serum reacted with yellow jacket venom but failed to react with the hornet venoms. Most sera from patients who had had allergic reactions after vespid stings reacted with yellow jacket and hornet venoms in RAST analysis. A few sera reacted with only one of the venoms. RAST inhibition studies confirmed the crossreactivity of these IgE antibodies. The IgG antibody response of 14 patients was measured after yellow jacket venom immunotherapy. All had rising titers of yellow jacket venom-specific IgG. There was also an increase in the IgG antibody response measured with hornet venom in the majority of patients. The rise was significant with yellow hornet venom (p less than 0.02) but failed to reach significance with bald-faced hornet venom (p greater than 0.05). In IgG radioimmunoassay inhibition studies using yellow jacket venom-coupled discs, yellow jacket venom was considerably more potent than hornet venom. These studies indicate major crossreactivity between yellow jacket and hornet venoms. In this group of patients, yellow jacket venom appeared to be the primary allergen.

Allergens↗
PubMed1982

Studies of chemically modified honeybee venom. I. Biochemical, toxicologic and immunologic characterization.

Allergens of honeybee venom (BV) were modified by formaldehyde treatment (F), acetoacetylation (A) or coupling to polyethylene glycol (P). The biochemical, toxicologic and immunologic properties of these modified BV preparations were analyzed. F showed strongly reduced cytotoxicity, enzymatic activity and reactivity with human BV-specific IgE antibodies but retained the reactivity to BV-specific human and rabbit IgG. In A, enzymatic activity, cytotoxicity and the reactivity with human IgE and rabbit IgG antibodies were only moderately reduced. P lacked enzymatic activity and cytotoxicity and showed only minimal reactivity with IgE and IgG antibodies to BV.

Acetoacetates↗
PubMed1982

Studies of chemically modified honeybee venom. II. Immunogenicity and suppression of reaginic antibody formation.

Honeybee venom allergens modified by formaldehyde treatment (F), acetoacetylation (A), and coupling to polyethylene glycol (P) were studied with regard to their immunogenicity and their IgE-suppressive potential in rabbits and mice. F indiced a strong IgG response in rabbits and especially mice, but only a moderate IgE response in the mouse. Its IgE-suppressive potential in mice was comparable to that of unmodified bee venom. A induced only a weak IgG and IgE response. Its IgE-suppressive potential was greater than that of unmodified bee venom. P was nonimmunogenic and had only a marginal IgE-suppressive effect. F and A seem promising for the treatment of bee sting-allergic individuals.

Acetoacetates↗
PubMed1981

Local intranasal immunotherapy for ragweed allergic rhinitis. I. Clinical response.

Local nasal immunotherapy (LNIT) of ragweed allergic rhinitis was studied in a double-blind controlled trial. Sixty-seven subjects were divided into three groups. Twenty-one received unmodified ragweed extract (RW), 24 received a glutaraldehyde polymer of ragweed extract (PRW), and 22 received placebo. Mean symptom/medication scores during the season were 2.12, 2.76, and 3.93 for the RW, PRW, and placebo groups, respectively. Both RW- and the PRW-treated group scores were significantly lower than those of the placebo group (p less than 0.01, and p less than 0.025, respectively). The results of the patients' self-evaluations indicated that therapy was effective in 71%, 59%, and 41% for the RW-, PRW-, and placebo-treated groups, respectively. Adverse reactions to treatment were limited to the upper respiratory tract and were noted by all patients. They were significantly more severe in the RW-treated patients than those in the PRW- or placebo-treated groups. We conclude that LNIT is an effective therapy for ragweed allergic rhinitis. The use of a PRW decreased adverse reactions significantly while slightly decreasing the therapeutic benefit.

Administration, Intranasal↗
PubMed1981

Local intranasal immunotherapy for ragweed allergic rhinitis. II. Immunologic response.

Local nasal immunotherapy (LNIT) was administered in a double-blind study to 67 subjects. Twenty-three received an unmodified ragweed extract (RW), 24 received a glutaraldehyde polymer of ragweed extract (PRW), and 21 received placebo. Serum ragweed-specific IgE (S-IgE), ragweed-specific nasal secretory (NS-) IgE, secretory IgA (SIgA) and IgG, and NS-albumin were measured. RW therapy caused a significant increase in ragweed-specific S-IgE (p less than 0.005) and NS-SIgA (p less than 0.05). PRW therapy caused a significant rise in ragweed-specific NS-SIgA (p less than 0.001). NS-IgE (p less than 0.05), and NS-IgG (p less than 0.01). Ragweed-specific S-IgG was not affected by any of the treatments. There was no consistent correlation between NS-antibody levels and symptom/medication scores.

Administration, Intranasal↗
PubMed1981

Comparison of vespid venoms collected by electrostimulation and by venom sac extraction.

Venoms of three vespid species, yellow jacket, bald-faced hornet, and yellow hornet, obtained by either electrostimulation of venom sac extraction were compared with regard to their enzymatic activity, antigenicity, and allergenicity. Phospholipase a, phospholipase B, and hyaluronidase enzymatic activities were present in all six preparations. The activity of venom sac extracts lay in the range found in different batches of venoms obtained by electrostimulation for each species. Analysis of sera from vespid-sensitive patients in the radioallergosorbent test (RAST) with discs coupled with either venom sac extracts or venoms obtained by electrostimulation showed a good correlation of the results within all three species (r = 0.95). In RAST inhibition the potency of venom sac extracts and venom obtained by electrostimulation was similar for each species. Analysis of rabbit antisera to the six preparations revealed similar patterns in immunoelectrophoresis and identity reactions between the major antigens within each species. Tissue protein contamination was detected in all venom sac extracts but not in venoms obtained by electrostimulation.

Animals↗
PubMed1980

Comparison of the venom immunogenicity of various species of yellow jackets (genus Vespula).

Venoms from various yellow jacket species were examined by two-dimensional thin-layer chromatography (TDTLC), double-diffusion gel precipitation (DDGP) using rabbit antisera, and the radioallergosorbent test (RAST). Comparison of representative venoms by the TDTLC showed that the venoms of V. vulgaris and V. maculifrons have a larger number of Ninhydrin (triketohydrindene hydrate)-positive substances than the venom of V. squamosa. The results of the DDGP confirmed the differences; venoms of V. vulgaris, V. maculifrons, V. flavopilosa, and V. germanica have one or more major components with immunogenic identity. The venom of V. squamosa has a species-specific major component and some minor components immunologically identical to the other venoms examined. Sera from 21 patients with a history of anaphylaxis following yellow jacket stings were examined by the RAST. Using the venoms of V. maculifrons, V. vulgaris, V. flavopilosa, and V. germanica as coupling antigens, most sera reacted similarly. The sera did not react with V. squamosa. These results suggest that the major component in venom obtained from the four yellow jacket species has immunogenic identity. Venom of V. squamosa differs from the remaining venoms. As a practical corollary, with the exception of venom from V. squamosa, common sensitivity appears to exist among the yellow jacket venoms examined.

Animals↗
PubMed1979

Sensitization to nonvenom contaminants in a venom preparation.

An individual is described who appeared to be sensitive to nonvenom contaminants in a venom preparation. His IgE antibodies, measured by the immediate direct skin test and the radioallergosorbent test (RAST), reacted with a yellow jacket venom preparation obtained by "washing" of venom sacs. With yellow jacket venom obtained by electriral stimulation, there was a skin test reaction of equivocal significance and no serum antibodies were detected by the RAST. Moderate reactions were also found with yellow jacket body extracts. In contrast, sera obtained from patients with yellow jacket sting anaphylaxis showed strong reactions with the electrically stimulated venom preparation and only a few reacted with the body extract. In additional studies, the patient's serum reacted with yellow jacket extracts devoid of venom and a variety of hornet and wasp extracts. Analyses of the two yellow jacket venoms by gel diffusion using rabbit antisera showed the presence of body proteins in the venom obtained by venom sac "washing." Subsequent history revealed the presence of insect nests in the roof of the patient's bedroom, perhaps the source of inhalant exposure and sensitivity. This case history demonstrates the need for venom extracts that do not contain potentially sensitizing extraneous material.

Adolescent↗
PubMed1976

Immunologic comparison of phospholipases A present in Hymenoptera insect venoms.

A comparative study was made of the effect of anti-bee venom phospholipase A2 serum and anti-bald face hornet venom serum on the activity of phospholipase A2 present in yellow hornet, yellow jacket, bald face hornet, and honeybee venoms. Activity of phospholipase A2 present in the venoms was measured titrimetrically using egg yolk dispersion as the substrate. Antiserum against pure bee venom phospholipase A2 activity completely suppressed bee venom phospholipase A2 activity but failed to inhibit phospholipase A2 activity in yellow jacket, yellow hornet, and bald face hornet venoms. Anti-bald face hornet venom serum suppressed the activity of phospholipase A2 present in the four insect venoms with the inhibitory effect decreasing in the order: bald face hornet greater than yellow hornet greater than yellow jacket greater than honeybee. A combination of immunoelectrophoresis and immunodiffusion techniques gave indication of common antigenic sites in a component of yellow hornet venom and a component of bald face hornet venom. The results suggest that IgG antibodies against pure bee venom phospholipase A2 may not give any protection against the reaction(s) due to the phospholipase A2 in yellow hornet, yellow jacket, and bald face hornet venoms, while antibodies against bald face hornet venom phospholipase A2 may give some cross-protection.

Animals↗