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D M Chang

Publications and source records attributed to D M Chang.

66 records · Page 4Linked to original sources
PubMed1988

[The interrelationships of hepatitis B e antigen antibody and HBsAg-circulating immune complexes in asymptomatic HBsAg carriers].

The prevalence of asymptomatic HBsAg carriers and positive rate of HBsAg immune complexes (HBsAg-CICs) were comparatively higher among Chinese. The former is considered to be related with hepatitis B e antigen and the latter is not clear yet. In order to investigate the relationship between HBsAg-CICs and e antigen antibody among asymptomatic carriers. 90 subjects of carriers was tested for HBsAg-CICs by PEG-trypsinisation method and for e antigen antibody by radio-immunoassay. HBsAg-CICs were positive in 66 subjects among 90 carriers. The concentration of HBsAg-CICs (ng/ml) was significantly higher among 32 subjects with positive HBeAg (333.87 +/- 265.39) than 27 subjects with positive anti-HBe (181.03 +/- 162.05), p less than 0.02. Furthermore, the positive rate of e antigen and e antibody was just contrary among carriers with positive and negative HBsAg-CICs. Among 24 subjects with negative HBsAg-CICs, the percentage of positive HBeAg was much lower than positive e antibody. A significant interrelationship was present between positive or negative HBsAg-CICs and e antigen, antibody, the statistically significant was proved by the Chi square test. The above results showed that the high prevalence of asymptomatic HBsAg carriers among Chinese may be related to e antigen.

Antigen-Antibody Complex↗
PubMed1987

[Specific circulating immune complexes in patients with hepatitis B].

Antigen specific hepatitis B surface antigen circulating immune complexes (HBsAg-CICs) were measured in 109 cases of hepatitis B with positive HBsAg (among them, 49 cases were acute and 60 cases were chronic hepatitis), 96 cases of asymptomatic hepatitis B surface antigen carriers, and 95 cases of normal blood donors. The mean concentration (ng/ml) of HBsAg-CICs was 303.50 +/- 357.70, 319.26 +/- 334.35 and 179.66 +/- 234.26 for the first three groups respectively; and was negative in normal groups. The concentration of HBsAg-CICs were significantly higher in acute and chronic group when compared with the asymptomatic carrier's group, (p less than 0.02 and p less than 0.01, respectively). Longitudinal series studies showed a close correlation between the levels or changes of HBsAg-CICs and the activity of the disease; patients with persistent HBsAg-CICs had a poor prognosis; and this were true not only in acute but also in chronic hepatitis patients. The mean concentration of HBsAg-CICs was higher in patients with positive hepatitis B e antigen (HBeAg) than in negative; but lower in patients with hepatitis B e anti-body (anti-HBe) positive than in negative. The higher prevalence of HBsAg-CICs in sera among asymptomatic HBsAg carriers in our study might be related to the prevalence of HBeAg among Chinese carriers. Further more, because HBsAg-CICs was related to the activity and prognosis of hepatitis B, it is worthwhile reconsidering whether so called "healthy" carriers were really healthy when their sera HBsAg-CICs tested positive.

Antigen-Antibody Complex↗
PubMedDate not supplied

Cytokines and cell surface markers in prediction of cardiac allograft rejection.

Endomyocardial biopsy is generally used to quantify heart allograft rejection and guide immunotherapy. Biopsy, however, is invasive, costly, and risky. Since rejection requires lymphocyte activation, the purpose of this study was to assess alternative methods to evaluate rejection dynamics by investigating serum levels of cytokines and cell surface markers after heart transplantation. Interleukin-2-receptor bearing CD4+T (IL-2R/CD4) cell levels were higher in the peripheral blood of human transplant recipients with rejection grade 2 (p < 0.02). HLA-DR/CD3 levels were somewhat higher in rejection grade 2. There was no correlation between biopsy scores and serum levels of tumor necrosis factor (TNF-alpha), IL-2, or percentage of T cell, NK cell, B cell, CD4+T cell, CD8+T cell, HLA-DR/CD4, HLA-DR/CD8, IL-2R/CD3, IL-2R/CD8. Interleukin-1 (IL-1 beta) was not detectable in all of the samples. The current studies suggest that monitoring lymphocyte IL-2R/CD4 and HLA-DR/CD3 levels is useful in predicting cardiac transplant rejection.

Adult↗
PubMedDate not supplied

Interleukin-1 and interleukin-1 receptor antagonist in systemic lupus erythematosus.

Interleukin-1 (IL-1) is thought to play an important role in the immunopathology of systemic lupus erythematosus (SLE). IL-1 receptor antagonist (IL-1ra) exhibits a dose-responsive inhibition of IL-1 effects, and Fcr receptors play a key role in IL-1ra production. To clarify the relationship between IL-1, IL-1 receptor antagonist (IL-1ra) production, and Fcr receptors in SLE, fifteen untreated lupus patients (9 females and 6 males) were evaluated. IL-1 and IL-1ra production from both monocytes and neutrophils was determined by both a murine thymocyte proliferation assay and ELISA. The expression of Fcr receptors on both monocytes and polymorphonuclear cells was measured by flow cytometry. There was no significant difference between IL-1 beta and IL-1ra production from ex vivo monocytes between lupus patients and normals. However, serum IL-1ra was significantly higher in lupus patients than in normals. The expression of FcrRII (CD32) on monocytes was lower in lupus patients than in normals. There was no correlation between the expression of FcrRII and the serum immune complexes; the production of IL-1ra and the expression of CD32, serum immune complex levels, and serum IgG. Both serum IL-ra and the production of IL-1ra had no correlation to SLEDAI, C3, C4, C1q, or ESR. These observations suggest that although IL-1 and IL-1ra may not play a major role in the initiation of pathogenesis of lupus, the low FcrRII expression in lupus may reflect low immune complex clearance and contribute to disease pathogenesis.

Adolescent↗