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Z N Chang

Publications and source records attributed to Z N Chang.

35 records · Page 2Linked to original sources
PubMed1991

Changes in the levels of house dust mite specific IgG4 during immunotherapy in asthmatic children.

Serum levels of IgG subclass and house dust mite (Dermatophagoides pteronyssinus, Dpt) specific IgG4 were evaluated during immunotherapy in asthmatic children. Asthmatic children undergoing long-term immunotherapy (more than 2 years) posed a mean value of total serum IgG4 or Dpt-specific IgG4 antibodies significantly higher than that of patients prior to receiving immunotherapy, asthmatic (placebo) controls, or patients undergoing short-term immunotherapy (less than 1 year) (P less than 0.05). The mean levels of serum Dpt-specific IgG4 in all asthmatic groups were also significantly higher than in the non-allergic controls (P less than 0.01). Moreover, the mean level of Dpt-specific IgG4 tended to increase during immunotherapy. A significant correlation between total serum IgG4 and Dpt-specific IgG4 antibodies was noted (r = 0.6243; P less than 0.001). Serial follow-up reveals that Dpt-specific IgG4 levels usually rose significantly with clinical improvement in asthmatic children during immunotherapy. These results suggest that the anti-mite-specific IgG4 antibody may serve as an indicator for clinical outcome of mite allergy during immunotherapy.

Animals↗
PubMed1991

A unique human IgE-binding epitope on the Bermuda grass pollen recognized by mouse lambda-type monoclonal antibodies.

A group of six mouse monoclonal antibodies (MoAbs) with the unusual lambda-type light chain were generated by fusion of NS-1 cells with splenic cells derived from BALB/c mice immunized with crude extracts of Bermuda grass pollen (BGP). Four of them were IgG1, one was IgG2b, and one was IgG3. Binding inhibition assay showed that they recognized the same (or very similar) epitope. Using sera from BGP-allergic patients, it was found that the specific binding between the IgE antibodies and the MoAb 26-11-fixed antigen could be blocked by MoAb 26-11 itself and another MoAb 9-13 in a dose-dependent manner. It appears that the epitope recognized by the lambda-type MoAbs is a human IgE-binding antigenic determinant. Further physico-chemical analyses showed that this epitope was stable under heat but sensitive to treatments of sodium periodate and proteinase K. Results from these studies indicate that this unique epitope which leads to the generation of lambda-type MoAbs is part of a glycoprotein.

Animals↗
PubMed1991

Analysis of allergenic components of Bermuda grass pollen by monoclonal antibodies.

A panel of 16 monoclonal antibodies (MoAbs) directed against Bermuda grass (Cynodon dactylon) pollen (BGP) were generated for identification and purification of the major allergenic components of the eliciting antigen (Ag). Radioimmunoprecipitation (RIP) analysis revealed that there were at least eight antigenic components with molecular weights (MW) ranging from 12 kilodalton (12 kDa) to 200 kDa. Each of these components has distinct biochemical characteristics based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and isoelectric focusing (IEF). Among them, Cyn d Bd67K and Cyn d Bd58K were basic proteins, Cyn d Bd35K consisted of at least four isomeric components with isoelectric points ranging from 6.2 to 7.2. The other antigens (Cyn d Bd68K, 48K, 38K, Cyn d Bd200K, Cyn d Bd46K, Cyn d Bd25K and Cyn d Bd12K) were all acidic proteins. The IgE binding capacity of all these antigens was determined with sera from 11 BGP-allergics by using a modified radioallergosorbent test. All but one of the antigens (Cyn d Bd200K) were found to react with human IgE from sera of BGP-allergic patients. Among those human IgE-binding molecules, Cyn d Bd35K reacted with allergic sera most frequently (10 of 11), followed by Cyn d Bd58K (8 of 11) and Cyn d Bd46K (7 of 11) respectively. Our results suggest that Cyn d Bd35K, Cyn d Bd58K, and Cyn d Bd46K are major allergens of BGP, and the MoAbs we obtained should be valuable tools for further purification of these allergens.

Allergens↗
PubMed1991

Allergenic components of Aspergillus fumigatus determined by radioimmunoprecipitation.

The allergenic components of Aspergillus fumigatus were identified using radioimmunoprecipitation (RIP) assay. Sera from 20 asthmatic children with positive skin tests to A. fumigatus were used for assay. Immune complexes formed between iodinated A. fumigatus and IgE antibodies in patients' sera were precipitated by immobilized anti-IgE monoclonal antibodies (MAbs). The precipitates were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and analyzed by autoradiography. It was found that IgE antibodies in the sera of allergic individuals reacted with several allergenic components of A. fumigatus ranging from 10 to 125 kD. Proteins of 38, 33, and 68 kD were recognized by IgEs from the allergic sera with frequencies of 85%, 65%, and 40%, respectively. It appears that these are the major allergenic components of A. fumigatus.

Allergens↗
PubMed1989

[Using anti-sera and monoclonal antibodies against Aspergillus fumigatus to study its cross-reactions with Alternaria alteria and Penicillium sp].

Using rabbit polyclonal and mouse monoclonal antibodies against Aspergillus fumigatus, we analyzed their cross-reaction with Alternaria alteria and Penicillium sp. by enzyme immuno assay (EIA) and radioimmunoprecipitation (RIP). It was found that neither of these two categories of antibodies reacted with Alternaria alteria while both reacted with Penicillium sp.. When components from Penicillium sp. precipitated by rabbit antisera were analyzed on 10% SDS-polyacrylamide gel electrophoresis (SDS-PAGE), a wide range of bands with molecular weights larger than 90 K and a single 70 K band were observed. No band was found after the rabbit antisera was adsorbed with Aspergillus fumigatus. Moreover, two monoclonal antibodies against Aspergillus fumigatus cross-reacted with high molecular weight (greater than 200K) components of Penicillium sp.. These results suggest that the antigen of Alternaria alteria is different from that of Aspergillus fumigatus, and that Penicillium sp. and Aspergillus fumigatus share some antigenic components. In another experiment, human allergic sera containing IgE antibodies to Aspergillus fumigatus were tested against Penicillium sp. by RIP. No cross-reaction was observed. This suggests that in spite of sharing common antigenic components between these two fungi, the allergenic components of Aspergillus fumigatus is different from those of Penicillium sp..

Alternaria↗
PubMed1988

Identification of allergens and antigens of Bermuda grass (Cynodon dactylon) pollen by immunoblot analysis.

Allergens and antigens of Bermuda grass pollen fractionated by SDS-polyacrylamide gel electrophoresis and transferred to nitrocellulose membranes were identified using twenty-one sera of Bermuda grass pollen-allergic patients. The IgE- and IgG-binding pollen components transferred to nitrocellulose were detected by reaction with enzyme-labelled anti-human IgE and anti-human IgG, respectively. There was heterogeneity in both IgE- and IgG-binding patterns of the allergic sera tested. Fourteen pollen components, ranging in molecular weight from 16,000 to 88,000 daltons, bound to IgE antibodies. Only two of the fourteen allergens identified reacted with IgE antibodies of more than 50% of the twenty-one allergic sera. The pollen component with a molecular weight of 32,000 daltons showed by far the highest frequency of IgE binding, being recognized by sixteen (76%) of the twenty-one sera examined. Fifteen (71%) of the twenty-one sera tested had IgE antibodies that reacted with more than one of the fourteen allergenic components identified. Pollen components recognized by IgE antibodies also reacted with IgG antibodies, and there were components only recognized by IgG antibodies. Results obtained from this study should be useful both clinically and in research.

Allergens↗
PubMed1988

Monoclonal antibodies specific for human IgE and their clinical applications.

By applying the hybridoma technique, two mouse anti-human Immunoglobulin E (IgE) monoclonal antibodies, designated as E17-58 and E20-62, were generated and characterized. E17-58 was a murine IgG2b with an affinity constant of 4 x 10(8)l/mole. E20-62 was a murine IgG1 with an affinity constant of 1 x 10(8) l/mole. These two antibodies recognized different antigenic determinants specific to the IgE molecule. They were used in combination to quantify the total serum IgE level of forty-nine persons. Data obtained correlated highly with that obtained by using the Pharmacia PRIST Kit (r = 0.91). E17-58 was also used to detect the anti-Aspergillus specific IgE of twenty-one atopic patients by a radioimmunosorbent test. The positive rate detected correlated very well with the skin test (p less than 0.05). In addition, in the Western blot system, these monoclonal antibodies were capable of identifying IgE binding components of crude allergen extracts. Extracts from pollens of Bermuda grass were evaluated, and a new major allergenic component with a molecular weight of 40 kd was identified.

Animals↗
PubMed1986

Immunophenotyping of myeloma cells with immunoalkaline phosphatase technique.

An immunoalkaline phosphatase (IAP) technique was used to determine the class of cytoplasmic immunoglobulin presenting in the malignant plasma cells of patients with multiple myeloma. Using monoclonal antibodies against different human immunoglobulins (Igs) as the primary antibodies, and calf intestinal phosphatase as the enzymatic indicator. The presence of monoclonal immunoglobulin was demonstrated within the cytoplasm of malignant plasma cells. These results correlate well with the electrophoretic patterns of the Igs present in the serum samples of these patients. This IAP technique is suggested as a practical method for evaluating the immunophenotype of multiple myeloma.

Alkaline Phosphatase↗
PubMed1985

[Autologous mixed lymphocyte reaction in systemic lupus erythematosus].

The autologous mixed lymphocyte reaction in patients with systemic lupus erythematosus was lower than that of normal individuals (p less than 0.05). The impairment was not due to the dysfunction of various regulatory lymphocytes, but there was a negative correlation with the B cell function. The low autologous mixed lymphocyte reaction was found in patients with high B cell function.

Adolescent↗
PubMed1985

The significance of CA19-9 tumor antigen in the serum of patients with carcinomas.

The concentration of serum CA19-9TM in 101 patients with colorectal adenocarcinoma (CRC), and 109 patients with carcinomas of lung, breast, stomach and pancreas and hepatoma, and 40 normal healthy controls including an equal number of smokers and nonsmokers were determined by solid phase radioimmunoassay of CA19-9 assay kits (Centocor). Of the normal sera, only 1 out of 40 (2.5%) was over 37.6 U/ml. No significant difference of CA19-9 levels was found between smokers (14.4 +/- 9.0 U/ml) and non-smokers (16.0 +/- 10.2 U/ml) of normal control. In patients sera, the mean value of CA19-9 levels was significantly higher in patients with Dukes B (P less than 0.05) and in patients with Dukes C and D (P less than 0.001) than the normal healthy control (15.2 +/- 10.2 U/ml). Analysis of serum CEA concentrations has shown a similar result in patients with all Dukes staged CRC. The CA19-9 levels was also significantly elevated in patients with gastric carcinoma, lung carcinoma, hepatoma, and especially in patients with pancreatic carcinoma (P less than 0.0001). The levels of CA19-9 elevated in 50% (22/44) of patients with advanced CRC while the elevation was 8 of 43 (18.6%) patients with localized CRC. A comparison of CA19-9 and CEA assays showed no correlation (r = 0.125) between the two assays. Although the CA19-9 assay (26.4%) was less sensitive than the CEA assay (51.7%), the specificity of CA19-9 assay (97.5%) was better than that of CEA assay (87.5%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗
PubMed1980

[Tissue typing of blood lymphocytes in normal Chinese and diseases (author's transl)].

The histocompatibility antigens were determined in 170 normal Chinese by a modified micro-lymphocytotoxicity test of Terasaki using 26 typing sera obtained from Behring Laboratories and Stanford University, and the data were compared with those obtained from 36 systemic lupus erythematosus, 30 rheumatoid arthritis, 17 ankylosing spondylitis as well as 45 leprosy patients. In normal individuals HLA-A2,A11 and A9 were dominant in locus A, the frequency were 42.35%, 41.76% and 32.35% respectively. HLA-Bw17, B13 and B5 were dominant in locus B, the frequency were 55.29%, 19.41% and 14.70% respectively. In systemic lupus erythematosus, the frequency of B8, Bw38 and A3 were slightly higher than normal (relative risk > 2); the frequency of Bw21 and B7 were little lower (risk of Bw21 < 0.5, frequency of B7 > 5% in normals but none in patients). In rheumatoid arthritis, the frequency of A28 and A10 (Aw25+26) were slightly lower than normal (risk < 0.5). In ankylosing spondylitis, the frequency of B27 was extremely high (risk = 44.92), Aw24 was also rather high (risk > 2); the frequency of B5, Bw35 and A10 (Aw25+26) was low (risk < 0.5), Bw15 and Bw21 > 5% in normals but none in patients. In leprosy, the frequency of B18 was relatively high (risk > 2); A3, Aw30+31+32, B27 and Bw35 were somewhat low (risk < 0.5). Because of the small sample size, however, the differences were not significant by Chi square analysis except the high frequency of B27 in ankylosing spondylitis (corrected P < 0.001).

Adult↗
PubMed1979

Factors contributing to impairment of the mixed lymphocyte reaction in leprosy.

Whereas the mixed lymphocyte reaction was essentially normal in inactive lepromatous leprosy and tuberculoid leprosy, it was severely impaired in active lepromatous leprosy. The impairment was found to be contributed by certain unknown factors in their plasma and subnormal reactivity of their T lymphocytes. The plasma derived from active lepromatous leprosy patients depressed the reaction of normal cells and normal plasma enhanced the reaction of active lepromatous lymphocytes. The cellular factor was studied by using a one-way reaction in which one of the two lymphocyte preparations was inactivated with mitomycin C. The impairment of blastogenesis of active lepromatous lymphocytes was partially reversed by substituting inactivated normal cells for similarly treated leprous cells, and conversely the response of normal allogeneic lymphocytes was depressed by substituting inactivated leprous lymphocytes as the stimulator cells.

Adult↗
PubMedDate not supplied

Isolation and partial characterization of a 46-kd allergen of Bermuda grass pollen.

Cyn d Bd46K, a 46-kD component of Bermuda grass (Cynodon dactylon) pollen, had been identified as an allergenic constituent. In the present study two-dimensional (2D) gel electrophoresis illustrated the presence of five acidic isoforms in Cyn d Bd46K, and this molecule was purified by monoclonal antibody (MAb) affinity chromatography for further characterization. Using a digoxigenin-labeled lectin-binding assay, the elucidating protein was disclosed to be a glycoprotein with terminal mannose. The involvement of a carbohydrate moiety in the allergenicity and antigenicity of the elucidated molecule was demonstrated with sodium-periodate-treated Cyn d Bd46K, which reduced binding to its specific MAb and human IgE. We were unable to identify the N-terminal amino acid sequences of Cyn d Bd46K, but some internal amino acid sequences were disclosed by microsequencing some fragments cleaved by Achromobacter protease I and fractionated by reversed-phase column chromatography. The amino acid sequences of 4 identified Cyn d Bd46K internal peptide fragments were found to be 25-71% identical with that of cytochrome c oxidase III from corn grass pollen. The present study provided important information for future experiments on the molecular cloning of the elucidated allergen.

Allergens↗