HLA-DQB1 codon 57 and IDDM in Chinese living in Taiwan.

OBJECTIVE: To study the human leukocyte antigen (HLA)-DQB1 genetic background in the Chinese population in Taiwan and its association with the low incidence of insulin-dependent diabetes mellitus (IDDM) in this population. RESEARCH DESIGN AND METHODS: Forty-eight IDDM patients and 59 nondiabetic unrelated control subjects were recruited from the population in Taiwan. HLA-DQB1 exon 2 was enzymatically amplified by polymerase chain reaction. HLA-DQB1 alleles were diagnosed by dot blotting and hybridization with 16 sequence-specific oligonucleotide probes. RESULTS: DQB1*0201 and DQB1*0302 alleles were more frequent and DQB1*0301 and DQB1*0601 were less frequent in Chinese with IDDM than in control subjects. Genotypes for homozygous non-aspartic acid residue (NA/NA) at position 57 were positively associated with IDDM at a relative risk of 4.34 (P < 0.001), and those for homozygous aspartic acid (A/A) were negatively associated with IDDM at a relative risk of 0.14 (P < 0.001). Among the NA/A heterozygotes, only DQB1*0201/DQB1*0303 was significantly increased in IDDM subjects. CONCLUSIONS: The amino acid residue at position 57 of HLA-DQ beta-chain is significantly associated with the development or prevention of IDDM in Chinese subjects living in Taiwan. Other genetic and environmental factors may also play important roles in pathogenesis of IDDM.

Human leukocyte antigen (HLA) frequency among patients with nasopharyngeal carcinoma in Taiwan.

In order to assess the association between human leukocyte antigens (HLA) and nasopharyngeal carcinoma (NPC), a total of 10 familial and 10 sporadic NPC patients and 171 unrelated healthy controls were studied. HLA typing was performed using commercial trays which defined 30 specificities of HLA-A, B and C loci and 10 specificities of HLA-D locus according to the method of Tiwari and Terasaki. HLA-A2, B16 and DR1 were found to be higher among patients with NPC than unrelated healthy controls with an odds ratio (OR) and a 95% confidence interval of 5.91 (2.1-16.6), 6.00 (2.0-18.0) and 6.89 (1.3-37.5), respectively. Further analysis showed that A2(+) B16(+) haplotype was significantly associated with a much higher risk of NPC (OR = 15.5) as compared with A2(-) B16(-) haplotype. No difference in frequency distributions of HLA-A, B, C and D antigens was observed between familial and sporadic NPC patients.

Epstein-Barr virus-associated antibodies and serum biochemistry in nasopharyngeal carcinoma.

Nasopharyngeal carcinoma is difficult to diagnose in its early stages. It also has frequent recurrences and/or distant metastases after radiotherapy. Extensive clinical, serological and biochemical studies were done during 1980-1982 on 351 patients to aid in the diagnosis of the disease, especially with recurrence or metastasis. Seropositive rates of the antibody titers against viral capsid antigens (VCA) and early antigens (EA) of Epstein-Barr virus (EBV) in IgG and IgA classes were 41.7%-100%. They ranked, in order of frequency: anti-VCA/IgA, anti-VCA/IgG, anti-EA/IgG, and anti-EA/IgA. Mean total serum IgG and IgA levels were moderately increased in all patients. Serum GOT, GPT, alkaline phosphatase, lactate dehydrogenase and mucoprotein were elevated either alone or in combination in a few patients before treatment, in many patients with recurrence or metastases, and in all patients with liver metastasis.

Prevalence of antibody to hepatitis C virus in pregnant Taiwanese.

To assess the prevalence of an antibody to hepatitis C virus (anti-HCV) in pregnant women in Taiwan, and elucidate whether or not there is superinfection of the hepatitis B virus (HBV) in such cases, we investigated two independent groups of pregnant women. Group A included 294 without serum alanine aminotranferase (ALT) screening, and group B included 171 pregnant women with an abnormal ALT level (greater than 45 IU/L) who were recruited from 9,523 pregnant women screened for ALT. Blood samplings were taken at early gestation and each serum sample was tested with an HCV EIA kit for anti-HCV. The results showed that 1 woman in group A (0.34%) and 4 women in group B (2.3%) were anti-HCV-positive. However, all 5 cases showed positive antibodies to both the hepatitis B surface and core antigens, but were negative for the hepatitis B surface antigen. Therefore, the prevalence of anti-HCV in pregnant women by current assay in Taiwan is 0.34% without ALT screening, but increases to 2.3% among abnormal ALT cases. The prevalence rate is less than the rates reported in other countries. If confirmed by subsequent study, the results suggest that infection with HCV is low among healthy young females in Taiwan today.

Evaluation of the A-60 IgG ELISA serodiagnostic test for tuberculosis in Taiwan.

To assess the applicability of a serologic test of specific IgG antibody for tuberculous infection in the Taiwan population, serum samples obtained from 118 subjects were analyzed by an ELISA test using mycobacterial antigen 60. There were 50 patients with a documented active infection caused by Mycobacterium tuberculosis (39 pulmonary tuberculosis, five pleurisy, three cervical lymphadenitis and three miliary tuberculosis with extrapulmonary involvement). Of these 50 patients, 42 (84%) showed a positive ELISA test (titer > 200 U). Of the 19 patients with inactive pulmonary tuberculosis, seven (37%) had a positive titer. Of the 22 patients with pulmonary disease other than tuberculosis, four (18%) showed a false-positive. In eight patients with autoimmune diseases, only the patient with rheumatoid arthritis had a positive reaction. One of the 19 healthy controls (5.3%) showed a false-positive result. The overall false-positive rate for the nontuberculous group was 12%. Follow-up examinations in 20 patients with active tuberculosis one month after treatment revealed that seven had an elevation in titers (three of them were initially negative and became positive later), five remained high and eight decreased in titers. Further examinations in six patients two months after treatment showed a decrease in titers. We conclude that this ELISA assay of specific IgG antibody is a valuable serologic test for diagnosis of M. tuberculosis infection. It may be useful in areas with a high prevalence of M. tuberculosis infection.

Genotype of classic congenital adrenal hyperplasia and the 60-minute adrenocorticotropic hormone stimulation test.

Twelve Taiwanese patients with classic congenital adrenal hyperplasia and 86 family members underwent human leukocyte antigen (HLA) genotyping and the 60-minute adrenocorticotropic hormone (ACTH) stimulation test. The baseline serum 17-hydroxyprogesterone level (mean +/- SEM) before ACTH testing was 1.595 +/- 792 nmol/L in homozygotes, 4.6 +/- 0.5 nmol/L in heterozygotes, and 2.1 +/- 0.8 nmol/L in the unaffected group. The stimulated serum 17-hydroxyprogesterone level (mean +/- SEM) was 1.926 +/- 778 nmol/L in homozygotes, 20.6 +/- 0.9 nmol/L in heterozygotes, and 6.8 +/- 0.6 nmol/L in the unaffected group. There was minimal overlap among the heterozygote and unaffected groups. The 60-minute ACTH stimulation test can provide clinicians with hormonal criteria for the assessment of the genotype of classic 21-hydroxylase deficiency in the Chinese population.

Human leukocyte antigen polymorphisms in the Taiwanese population.

Polymorphisms of human leukocyte antigens (HLA) are important in transplantation medicine, anthropologic studies, and paternity testing. We investigated the polymorphisms of HLA classes I and II in the Taiwanese population by means of serologic typing and polymerase chain reaction (PCR) analysis with sequence-specific primers. We calculated the HLA-A, -B, and -C gene frequencies in 673 Taiwanese subjects and the HLA-DRB1, and HLA-DQB1 gene frequencies in 204 subjects with available DNA samples. Haplotype frequencies and linkage-disequilibrium were analyzed on the basis of these data. The common HLA class I antigens were A11 (gene frequency, 34.9%), A2 (29.3%), A24 (15.8%), and A33 (9.8%); B60 (21.9%), B46 (13.1%), B58 (9.7%), and B13 (8.5%); and Cw1 (18.8%), Cw7 (15.3%), and Cw10 (10.7%). The common HLA-DRB1 and HLA-DQB1 alleles were DRB1*12 (15.2%), DRB1*09 (15.2%), DRB1*08 (12.0%), and DRB1*04 (12.0%); and DQB1*0301 (23.5%), DQB1*0303 (15.2%), DQB1*0601 (14.5%), and DQB1*02 (10.8%). The common two-locus haplotypes were A2-B46 (frequency, 9. 7%), A11-B60 (9.6%), and A33-B58 (6.8%); DRB1*09-DQB1*0303 (14.9%), DRB1*12-DQB1*0301 (14.2%), and DRB1*08-DQB1*0601 (10.7%). This study is the first to report the gene frequencies of HLA-DQB1 alleles and the common HLA-DR-DQ haplotypes among Taiwanese. Comparison of our results with those from two other Chinese populations in mainland China reveals that Taiwanese are more closely related to southern Han than to northern Han Chinese.

Strong association of antiepithelial cell antibodies with HLA-DR3 or DR7 phenotype in patients with recurrent oral ulcers.

BACKGROUND: Previous studies showed that antiepithelial cell antibodies (anti-ECA) were present in 71% (15/21) of patients with recurrent oral ulcers (ROU) and that there was a strong association of human leukocyte antigen (HLA)-DRw9 with ROU in Chinese patients. In this study, we assessed anti-ECA in a larger group of Chinese patients with ROU (n = 88) in order to further investigate the association of anti-ECA with HLA-DR and -DQ antigens. METHODS: The anti-ECA in the sera of ROU patients were detected by an indirect immunofluorescence technique with rat esophagus as the substrate, and the HLA-DR and -DQ antigens in ROU patients were typed by a standard microcytotoxicity assay using Terasaki's oriental tray. RESULTS: The rate of anti-ECA positivity was significantly higher (p < 0.0001) in ROU patients (68%) than in healthy control subjects (0%). Furthermore, the rate of anti-ECA positivity in patients with major or minor oral ulcers (72%) was significantly higher (29%) than that in patients with herpetiform ulcers (p < 0.05). There was a significant increase in the frequency of DR3 or DR7 antigen expression (p < 0.0001, pc [p corrected] < 0.001, relative risk [RR] = 4.3, etiologic fraction = 0.41) in anti-ECA-positive ROU patients compared with the corresponding frequencies in healthy control subjects. There was also a significant increase in the frequency of DR7 or DRw9 antigen expression (p < 0.005, pc < 0.05, RR = 4.7, etiologic fraction = 0.45) compared to healthy controls. CONCLUSIONS: Because only DR3 or DR7 antigen occurred more frequently in anti-ECA-positive than in anti-ECA-negative ROU patients (p < 0.0007, pc < 0.05, RR = 19.6, etiologic fraction = 0.51), we concluded that the gene coding for DR3 or DR7 antigen may contribute to the presence of anti-ECA in Chinese patients with ROU.

Monoclonal gammopathies and the related autoimmune manifestations in Taiwan.

A total of 50,000 patients were surveyed for the presence of monoclonal immunoglobulins during the past two decades. There were 411 cases of monoclonal gammopathies including 243 cases of plasma cell neoplasms and 168 cases of secondary plasma-cell dyscrasia. Among the 227 cases of multiple myeloma and Waldenström's macroglobulinemia, there were 49.3% IgG class, 22.9% IgA class, 9.7% IgM class and 13.2% light chain type. In addition, there were 1.3% of nonexcretory myeloma including an IgM type. A relatively high frequency (4.8%) of IgD M-proteins was detected but heavy chain disease was not encountered in the present series. Purified M-components from patients with possible autoimmune manifestations were subjected to immunofluorescence studies. Autoimmune activity of M-proteins was found in a patient of Waldenström's macroglobulinemia with peripheral neuropathy, and another patient of cryofibrinogenemia with recurrent purpura and gangrene. In conclusion, a high frequency of IgD myeloma is found in Chinese patients of this area. M-components may have autoimmune activity resulting in unusual clinical manifestations.

Altered distribution of lymphocyte subpopulations and augmentation of lymphocyte proliferation in chronic PCB poisoned patients.

To clarify the mechanism of immunotoxicity of polychlorinated biphenyls (PCB), delayed type hypersensitivity skin test, lymphoproliferative responses, and lymphocyte subpopulations defined by monoclonal antibodies were performed on 30 patients and 38 age/sex-matched healthy individuals. Three years ago the patients had ingested rice bran oil accidentally contaminated by PCB. Except for lymphocyte proliferation, the chronic effect of PCB and its derivatives upon cell-mediated immunity (CMI) in these patients was not so evident when compared to that found within one year of exposure. Delayed type hypersensitivity skin response to purified protein derivative (PPD) and the numbers of peripheral T and B lymphocytes were within normal range. The enumeration of lymphocyte subsets demonstrated decreased T4 (inducer/helper) cells and increased T8 (cytotoxic/suppressor) cells. The abnormally augmentated spontaneous proliferation and proliferation responses to phytohemagglutinin (PHA), concanavalin A (Con A), pokeweed mitogen (PWM) and PPD implicated that both T and B lymphocytes were functionally affected. This may well be the result of the immunotoxicity rather than the enhancement of cell-mediated immunity by these toxic compounds. While there was no correlation between the results of those assays and blood PCB levels, it appears that the lymphoproliferative assay may be applied as a sensitive test in reflecting the severity of PCB immunotoxicity.

[A comparative study of antinuclear antibody measurement using different cells as nuclear substrates].

In an attempt to evaluate possible variations in the antinuclear antibody (ANA) titers resulting from nuclear substrate difference, we measured the ANA titer of 104 normal subjects using substrates from mouse liver cell (MLC) and HEp-2 cell (CSI, USA). We also performed similar experiments on 50 sera from 50 patients with rheumatic disease using mouse liver cell, HEp-2 cell (CSI), HEp-2 cell (AFT, Japan), and HEp-2 cell (AI, USA) as substrates. The ANA titer assay using HEp-2 cell (CSI), which is routinely used in our laboratory, was regarded as the reference method. The results showed that when HEp-2 (CSI) was used, 98.1% normal subjects had ANA titer lower than 1:320, therefore a cut-off value of 1:320 was used. While using the MLC method, 96.2% normal subjects had ANA titer lower than 1:80, and the cut-off value was set at 1:80 accordingly. The geometric mean ANA titers of the 50 sera from 50 rheumatic disease patients were 676 for HEp-2 cell (CSI), 503 for HEp-2 cell (AFT), 368 for HEp-2 cell (AI), and 265 for MLC, respectively. Although statistically significant difference (p less than 0.05) in geometric mean titer existed between reference method and the other 3 methods, the latter 3 methods still had good sensitivity (97.2% for HEp-2 cell (both AFT and AI); 91.7% for MLC), and specificity (100% for HEp-2 cell (both AFT and AI); 71.4% for MLC) for selecting out sera with abnormal ANA titer. We also evaluated the relationships between ANA titer and anti-double stranded DNA antibody (anti-dsDNA) concentration in another 210 sera from 151 patients with rheumatic disease. Statistically, there is no distinct correlation between anti-dsDNA and ANA of all fluorescence staining patterns except for peripheral pattern, in which case a significant correlation could be demonstrated.

Lymphocyte subsets and EB virus antibodies in nasopharyngeal carcinoma.

Lymphocyte subsets and Epstein-Barr virus (EBV)-associated antibodies were studied in 108 patients with nasopharyngeal carcinoma (NPC) and in 34 normal controls. Lymphocyte subsets were identified with monoclonal antibodies (Ortho Co.) by indirect immunofluorescent antibody (IFA) method. The helper T lymphocytes (OKT4+) in NPC patients comprised 38.2 +/- 10.5% which is significantly different from 45.2 +/- 8.0% in controls. The helper/suppressor ratio in NPC patients was 1.33 +/- 0.65 which is significantly different from 1.64 +/- 0.48 in controls, but the ratio was not correlated with disease extent, sex, age, total lymphocyte counts, WBC counts and EBV-associated antibodies of NPC patients. There were no remarkable differences between NPC patients and controls in B lymphocytes (OKIa+), total T lymphocytes (OKT3+), and suppressor lymphocyte (OKT8+) percentages, total lymphocyte counts and WBC counts. The EBV-associated antibodies were titrated by the IFA method using P3HR-1 cells and Raji cells induced by IUdR as target. Mean antibody titers and seropositive rates showed significant increase in NPC patients (1:12-1:502 and 45.4%-68.5%, respectively) compared with controls (1:1-1:87 and 1.0%-5.9%, respectively). The increase in antibodies was positively correlated with NPC disease extent, but was not correlated with the sex, age, total lymphocyte counts, helper/suppressor ratio, and WBC counts of NPC patients.