Antinuclear antibodies detection: A comparative study between automated recognition and conventional visual interpretation.

BACKGROUND: The indirect immunofluorescence assay (IIFA) for the detection of antinuclear antibodies (ANA) was firstly described in 1958 and is still considered the reference method for ANA screening. Currently, an automated processing and recognition system for standardized and efficient ANA interpretation by human epithelial (HEp-2) cell-based immunofluorescence (IIF; EUROPattern Suite, Euroimmun) is available in China. METHODS: In this study, the performance of this novel system for positive/negative classification, pattern recognition (including homogenous, speckled, nucleolar, nuclear dots, cytoplasmic, and centromeres patterns) and titers evaluation was evaluated by comparing to visual interpretation. RESULTS: Referring to the total of 3681 collected samples, there was an agreement of 98.7% (κ = 0.973) between the visual and automated examination regarding positive/negative discrimination. In sera with single pattern, correct pattern recognition was observed in 94.6% of the samples. The efficiency of automated recognition for single pattern varied for the different patterns. The automatically determined patterns were correct and complete in 1071 of 1620 cases and correct and meaningful but not complete ("main pattern") in another 405 cases, enabling main pattern recognition in 91.1% of all cases. Referring to the titers evaluation, the results within the next titer were considered to be consistent. In 1603 positive sera both by visual and automated evaluation, titers of 1514 sample were consistent, accounting for 94.4%. CONCLUSION: Attributed to the performance characteristics, EUROPattern system is suitable for clinical use as its high degree of automation and result reliability, and may help clinical laboratories to standardize of IIF evaluation.

Neutrophil and Eosinophil Granule Proteins as Potential Biomarkers of Assessing Disease Activity and Severity in Patients With Ulcerative Colitis.

BACKGROUND: Colonoscopy can assess disease activity and severity of ulcerative colitis (UC) accurately, but it is invasive and costly. Role of noninvasive biomarkers of intestinal inflammation in evaluation of patients with UC is not well understood. In this study, we assessed fecal eosinophil cationic protein (FECP), fecal myeloperoxidase (FMPO), and fecal calprotectin (FC) as surrogate markers of disease activity and severity in patients with UC, and then evaluated effect of the combination of these markers. METHODS: Sixty-three UC patients and 59 cases of age-matched controls were investigated. All patients underwent clinical, endoscopic, and histological assessment for disease activity and severity. Fecal samples were analyzed for FECP, FC, and FMPO. RESULTS: All three fecal biomarkers were elevated in patients compared with controls (P = 0.000). Significant differences were found between inactive UC and controls (P = 0.000). Cases with severe UC had significantly higher FECP levels than those with mild UC (p < 0.05), but there were no significant differences in FC and FMPO levels among disease severity groups. All three biomarkers showed positive correlation with Ulcerative Colitis Activity Index (UCAI). The areas under the ROC curve of FECP, FC, and FMPO were 0.939, 0.783, and 0.785, respectively. Sensitivity and specificity of fecal biomarkers in assessing disease activity were FECP-88.46%, 89.47%; FC-80.77%, 68.42%; and FMPO-84.62%, 63.16%. CONCLUSIONS: All three fecal biomarkers could be used as surrogate markers for assessing disease activity of UC, and FECP provided superior discrimination than FMPO and FC. Moreover, FECP could distinguish between mild disease and severe disease group.

Evaluation of an Automated Chemiluminescent Immunoassay in Typing Detection of IgG Antibodies Against Herpes Simplex Virus.

BACKGROUD: Herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) are common infectious agents worldwide and the primary infection of HSV remains a major problem in the pregnant women in China nowadays. At present, typing detection of HSV is mainly based on ELISA in China. METHODS: In this study, we evaluated the performance of a newly introduced chemiluminescent immunoassay assay (CLIA) for the determination of serum HSV-1 and HSV-2 immunoglobulin G (IgG) antibodies. RESULTS: The functional sensitivity of detecting HSV-1 and HSV-2 IgG were 0.7 Index and 0.6 Index, respectively. The repeatability and the total imprecision coefficient of variations were both below 10%, and the recoveries of these assays ranged from 90% to 110%. High concentration of hemoglobin, lipids, and bilirubin in samples did not affect the results. The infective rates of HSV-1 and HSV-2 were 919 (87.5%) and 169 (16.1%), respectively. HSV-1 seroprevalence was significantly higher than that of HSV-2 (P < 0.001). CONCLUSION: CLIA is an excellent method for HSV-1 and HSV-2 IgG measurement and can be used as a routine screening test. The infective rate of HSV was pretty high among women before pregnancy or in the period of pregnancy in Beijing.

T-Cell Receptor ß Chain and B-Cell Receptor Repertoires in Chronic Hepatitis B Patients with Coexisting HBsAg and Anti-HBs.

Antibodies in response to antigens are related to the immune repertoire of T- and B-cell receptors. However, some patients with chronic hepatitis B (CHB) have coexisting HBsAg and anti-HBsAg antibodies (anti-HBs) that cannot neutralize HBV. We attempted to investigate the repertoires that produce this response in CHB patients. The T-cell receptor ß chain (TRB) and B-cell receptor (BCR) repertoires of peripheral blood genomic DNA were analyzed using MiXCR. T-cell receptor (TCR) cluster analysis was carried out by clusTCR, and motifs prediction was selected by Multiple Em for Motif Elicitation (MEME). A total of 76 subjects were enrolled, including 26 HBsAg and anti-HBs coexisting patients with CHB (DP group), 25 anti-HBs single-positive healthy people (SP group), and 25 CHB patients (CHB group). The clone length of BCR in 39, 90 was significantly different among these groups (p = 0.005, 0.036). The motif "CASSLG" in the DP group was significantly higher than SP and CHB groups and may relate to coexistence, and the motif "GAGPLT" was only shown in the SP group and may relate to anti-HB expression. These provide important insights into vaccine development and CHB treatment.

Evaluation of BD Vacutainer SST™ II plus tubes for special proteins testing.

In the past few years, because of providing a closed system that allowed for collection, transport, processing, sampling, and storage of specimens, serum separator tubes gained widespread acceptance gradually in China. However, some limitations associated with gel tubes had been observed, for example, gel and analyte stability. In order to circumvent these problems, a new tube (BD Vacutainer(®) SST™ II Plus (BD SST™ II Plus)) containing a new gel was released by BD with respect to analyte and gel stability. We investigated the performance of BD SST™ II Plus tubes for special proteins testing using BD Vacutainer(®) Serum Glass Tubes (BD Serum Glass) as controls.Equivalence between these two types of tubes was demonstrated for all analytes at initial time, and data for all analytes except complement 3 (C3) and complement 4 (C4) indicated comparable stability over time in these two types of tubes. Concentration of C3 and C4 tended to increase with preservation time up to 72 hr in BD Serum Glass tubes. The stability of C3 and C4 was better in BD SST™ II Plus, which was demonstrated at timepoints up to 48 hr. We conclude that BD SST™ II Plus was suitable for collection and storage of samples for special proteins testing.

Evaluation of BD Vacutainer SST™ II Plus tubes for common tumor marker tests by Roche Diagnostics Modular E 170 analyzer.

Serum separator tubes were introduced 35 years ago and were widely used in the clinical laboratory in China for routine collection of blood because of providing a closed system that allowed for collection, transport, processing, sampling, and storage of specimens. This type of tubes facilitated rapid separation of serum from cellular constituents of blood and also prevented hemolysis upon prolonged storage. However, there were some limitations associated with gel tubes (i.e., gel and analyte stability). In order to circumvent these problems, BD released a new serum separator tube containing a new gel (BD SST(™) II Plus). We investigated the performance of BD SST(™) II Plus tubes for tumor marker tests using BD Serum Glass tubes as controls. Equivalence between the BD SST(™) II Plus and BD Serum Glass tubes was demonstrated for all analytes at initial time. Also, all analytes remained stable when stored in BD SST(™) II Plus tubes up to 72 hr. Concentration of neuron-specific enolase tended to increase with preservation time up to 72 hr in BD Serum Glass tubes. We conclude that BD SST(™) II Plus was suitable for collection of blood and storage of serum for tumor marker tests.

Seroepidemiology of TORCH antibodies in the reproductive-aged women in China.

TORCH, the acronym of Toxoplasma gondii (TOX), others, rubella virus (RUV), cytomegalovirus (CMV) and herpes simplex virus (HSV), is a major contributor to congenital infection. National population-based study on the seroepidemiology of TORCH in women is yet lacking, and it is still obscure whether TORCH infection in the women was associated with adverse pregnancy outcomes. A total of 48,406 asymptomatic women from eight hospitals in China which covered the most areas of mainland China were enrolled in this study, and 26,400 were simultaneously subjected to 7 detection tests for TORCH specific antibodies. Chemiluminescent immunoassay was performed to detect TORCH Immunoglobulin M (IgM) and/or Immunoglobulin G (IgG) antibodies, and IgG avidities of TOX and CMV IgM and IgG positive serum samples. The overall IgG prevalence of TOX, RUV, CMV and HSV-(1 + 2) in the reproductive-aged women was 1.71 %, 81.97 %, 95.09 % and 90.15 % respectively. The corresponding IgM prevalence of TOX, RUV and CMV was 0.30 %, 0.89 % and 0.52 %. Moreover, the rates of primary TOX and CMV infections were at least 0.08 % (21/26,400) and 0.03 % (7/26,400) in the studied population. The distributions of TORCH positive women in various age, season and region groups were different (P < 0.05). The CMV IgM-positive rate was higher in the pregnant women than those in non-pregnant women (P < 0.05). The higher past infection rates of RUV, CMV and HSV in women with bad obstetric history (BOH) imply that TORCH infections are associated with BOH. These data suggest that TORCH infections in the prenatal women, especially with BOH, are worthwhile to be screened by detections of specific IgG and IgM antibodies, and even IgG avidities.

New Gene Variants Associated with the Risk of Chronic HBV Infection.

Some patients with chronic hepatitis B virus (HBV) infection failed to clear HBV, even persistently continue to produce antibodies to HBV. Here we performed a two stage genome wide association study in a cohort of Chinese patients designed to discover single nucleotide variants that associate with HBV infection and clearance of HBV. The first stage involved genome wide exome sequencing of 101 cases (HBsAg plus anti-HBs positive) compared with 102 control patients (anti-HBs positive, HBsAg negative). Over 80% of individual sequences displayed 20 × sequence coverage. Adapters, uncertain bases > 10% or low-quality base calls (> 50%) were filtered and compared to the human reference genome hg19. In the second stage, 579 chronic HBV infected cases and 439 HBV clearance controls were sequenced with selected genes from the first stage. Although there were no significant associated gene variants in the first stage, two significant gene associations were discovered when the two stages were assessed in a combined analysis. One association showed rs506121-"T" allele [within the dedicator of cytokinesis 8 (DOCK8) gene] was higher in chronic HBV infection group than that in clearance group (P = 0.002, OR = 0.77, 95% CI [0.65, 0.91]). The second association involved rs2071676-A allele within the Carbonic anhydrase (CA9) gene that was significantly elevated in chronic HBV infection group compared to the clearance group (P = 0.0003, OR = 1.35, 95% CI [1.15, 1.58]). Upon replication these gene associations would suggest the influence of DOCK8 and CA9 as potential risk genetic factors in the persistence of HBV infection.

Screening for antibodies against Treponema pallidum with chemiluminescent microparticle immunoassay: analysis of discordant serology results and clinical characterization.

BACKGROUND: Traditionally, testing for syphilis has consisted of initial screening with a non-treponemal test, then retesting reactive specimens with a treponemal test. Recent availability of a chemiluminescent microparticle immunoassay for detecting antibodies against Treponema pallidum has led several laboratories in China to adopt chemiluminescent microparticle immunoassay for screening of syphilis, with subsequent testing of reactive serum samples with non-treponemal tests. We evaluated the utility of chemiluminescent microparticle immunoassay for routine screening of syphilis. METHODS: Antibodies against Treponema pallidum were screened in 20,550 serum samples using chemiluminescent microparticle immunoassay. Chemiluminescent microparticle immunoassay-positive samples were reflexively tested with rapid plasma reagin tests and Treponema pallidum particle agglutination assays. Dot-immunoblot assays were used to confirm results of chemiluminescent microparticle immunoassay-positive and Treponema pallidum particle agglutination-negative serum samples. RESULTS: Overall, 267 samples (1.3%) were chemiluminescent microparticle immunoassay-positive, and 185 (69.3%) of those chemiluminescent microparticle immunoassay-positive serum samples were also Treponema pallidum particle agglutination-positive. Samples' signal to cut-off ratio for chemiluminescent microparticle immunoassay correlated with diagnostic reliability, as greater samples' signal to cut-off ratio corresponded with greater concordance between chemiluminescent microparticle immunoassay and Treponema pallidum particle agglutination results. Dot-immunoblot testing of 82 chemiluminescent microparticle immunoassay-positive and Treponema pallidum particle agglutination-negative serum samples showed that 16 samples (19.5%) were Dot-immunoblot-positive, 28 (34.2%) were indeterminate and 38 (46.3%) were negative. CONCLUSIONS: Because there is a certain percentage of false-positive results using chemiluminescent microparticle immunoassay for routine screening of syphilis, further analysis by Treponema pallidum particle agglutination is recommended to confirm diagnostic results. While in screening populations discrepancies between chemiluminescent microparticle immunoassay and Treponema pallidum particle agglutination results are quite prevalent, confirmation by immunoblot assay may be useful.

Serological diagnosis of infectious mononucleosis by chemiluminescent immunoassay using capsid antigen p18 of Epstein-Barr virus.

BACKGROUND: Infectious mononucleosis is the common clinical manifestation of primary Epstein-Barr virus (EBV) infection in young children. We evaluated a chemiluminescent immunoassay method for the determination of serum anti-viral capsid antigen IgM antibody and its clinical value in the diagnosis of infectious mononucleosis. METHODS: Concentrations of the antibody in serum samples from 187 children measured by chemiluminescent immunoassay were compared with those measured by ELISA. RESULTS: Assessment of technologic quality (methodology) in diagnostic tests demonstrated that sensitivity of CLIA was 0.64 U/ml and the functional sensitivity was <0.9 U/ml. The within-assay and the between-assay imprecisions of different concentrations were all <5%. Recoveries were all in 93-107%. The linear regression equation between expected values and measured values was y=0.0967+1.0093x, correlation coefficient was 0.9996 (p<0.0001). The ROC curve showed that the sensitivity and specificity of the CLIA both were >90%. The area under the curve was 0.992, which was significantly higher than that of ELISA (p<0.05). CONCLUSION: The CLIA was the excellent method for EBV-VCA IgM measurement at present and can improve the clinical diagnosis of infectious mononucleosis.

Evaluation of the clinical effectiveness of HIV antigen/antibody screening using a chemiluminescence microparticle immunoassay.

Human immunodeficiency virus (HIV) screening assays have improved from single-antigen detection to detection of antigen-antibody combinations. However, concerns have been raised over the potential for false-positive results in antigen-antibody combination assays. The present study investigated the clinical effectiveness of HIV antigen/antibody (HIV Ag/Ab) combination screening by chemiluminescence microparticle immunoassay (CMIA) in over 88,000 samples from an HIV low-prevalence area of Beijing, China. The HIV Ag/Ab CMIA screening results were consistent with those obtained by Western blot and HIV-RNA testing, and had an accuracy of 99.74% (Kappa index=0.98). False-positive results were more common for women affected by clinical interfering factors (e.g., kidney disease, tumors) than for men (80.95% vs. 15.09%, P<0.001). When CMIA signal-to-cutoff ratio (S/CO) was 11.26, the sensitivity and specificity were highest (100%, 99.43%), and the area under the ROC curve (AUC) was 0.998. Specimens that were negative by CMIA (S/CO <1) were all negative by HIV-RNA testing. These results indicate that HIV Ag/Ab CMIA has a good clinical performance; however, some clinical interfering factors should be considered in HIV low-prevalence areas for their potential to skew testing results.

[Expression and purification of recombinant N-terminal protein of SARS S1 subunit expressed in E. Coli].

OBJECTIVE: To express and purify the recombinant N-terminal protein of SARS virus S1 subunit and to study its role in SARS immune response. METHODS: The gene encoding N-terminal 334 amino acid residuals of SARS virus S1 subunit was cloned and expressed in E. Coli. After purification, the recombinant protein was identified by anti-SARS positive sera from recovered SARS patients. The sera from health donors, which were collected before the out-break of SARS, were used as negative control in the study. RESULTS: Sequencing analysis confirmed that the desired DNA sequence in recombinant plasmid was correct and had the same sequence of natural N-terminal of SARS virus S1 subunit. The molecular weight of recombinant fusion protein is about 64 000. The recombinant S1 protein could react with three antibody positive samples from recovered SARS patients, which showed specific bands at 64 000, but not with the control samples according to results of western blot. CONCLUSION: The recombinant N-terminal protein of SARS virus S1 subunit displays specific reaction with SARS antibody and may provide a good tool for further research of immune response to SARS virus.

[Primary investigation on the changing mode of plasma specific IgG antibody in SARS patients and their physicians and nurses].

OBJECTIVES: To primarily investigate the changing mode of anti-SARS coronavirus IgG antibody in clinically diagnosed SARS patients and the possibility of subclinical infection in physicians and nurses through close association with SARS patients. METHODS: The plasma levels of anti-SARS coronavirus IgG antibody of 57 normal subjects, 127 physicians and nurses worked in SARS wards for one month and 73 SARS patients with different course of SARS were measured by enzyme linked immunosorbent assay. RESULTS: Plasma anti-SARS coronavirus IgG antibody was not detected in normal subjects and the clinical personnel. After 0-7 days, 8-10 days, 11-14 days, 15-20 days of onset of disease, the positive rates were 0.33%, 52%, 86% respectively, and the general positive rate was 61%. CONCLUSION: The specificity and sensitivity of ELISA to detect plasma anti-SARS IgG antibody were satisfactory. Cases with positive reaction could be diagnosed as patients already infected by the virus. The specific IgG antibody didn't emerge in some patients in the early stage of the disease, and the negative results didn't indicate that they were not infected. And follow-up investigation should be made in those patients. Unlike common epidemic infectious diseases, SARS probably hadn't the potentiality of subclinical infection.

Prevalence of serum antibodies to TORCH among women before pregnancy or in the early period of pregnancy in Beijing.

BACKGROUND: The primary infection of Toxoplasma gondii (TOX), rubella virus (RV), cytomegalovirus (CMV), or herpes simplex virus (HSV), abbreviated as TORCH, remains a major problem in the pregnant women in China today. METHODS: We analyzed the performance of a novel chemiluminesent immunoassay (CLIA) for anti-TORCH IgM and IgG detection then analyzed the prevalence of TORCH infection among 4692 women at childbearing age in Beijing, China. RESULTS: The functional sensitivity of detecting anti-TOX IgM, anti-RV IgM, anti-CMV IgM and anti-HSV (types 1 and 2) IgM were 1.4, 3.2, 1.0 AU/ml and 0.5 index, respectively. The within-assay and the total CVs were both <10%, and recoveries of these assays ranged from 90-110%. High concentration of hemoglobin, lipids and bilirubin in sample did not affect the results. The infective rate of TORCH was 17.2%, with the highest positive rate of anti-HSV IgM. Within anti-TORCH IgG, anti-CMV IgG had the highest infective rate, 92.5%. CONCLUSIONS: The infective rate of TORCH was fairly high among women before pregnancy or in the early period of pregnancy in Beijing. Entirely new approaches to prevention and treatment of congenital TORCH infection are necessary.

Prevalence of antinuclear and anti-liver-kidney-microsome type-1 antibodies in patients with chronic hepatitis C in China.

BACKGROUND: Hepatitis C virus (HCV) infection may induce autoimmune response and autoantibodies can be detected in chronic hepatitis C (CHC) patients. However, the reported positive rate of autoantibodies in CHC patients in China varies considerably. In this study, we investigated the prevalence of antinuclear antibodies (ANA) and anti-liver-kidney-microsome type 1 autoantibodies (anti-LKM-1) in a large cohort of CHC patients, and analyzed the factors related to the presence of the autoantibodies. METHODS: A total of 360 CHC patients were enrolled in this study. Serum ANA and anti-LKM-1 were detected by indirect immunofluorescence and enzyme-linked immunosorbent assay, respectively. Clinical analysis was performed to disclose the related factors to autoantibody production. RESULTS: The prevalence of ANA and anti-LKM-1 in CHC patients was 12.5% (45/360) and 2.5% (9/360), respectively. Women had a higher prevalence than men (18.9% vs 11.4%, P = 0.046). Patients with positive autoantibodies had lower HCV RNA levels (1.2 x 10(7) copies/L vs 7.2 x 10(7) copies/L, P < 0.05). Positive ANA was associated with higher serum globulin (P < 0.05). Stratified analysis showed that there were no significant differences in age, HCV genotype, disease course, clinical stage, prevalence of cirrhosis and interferon therapy between autoantibody-positive and -negative subgroups. CONCLUSION: Autoantibodies can be induced in the course of CHC, and some CHC patients can even develop autoimmune hepatitis.

[Detection and the production mechanism of antinuclear antibodies (ANA) and anti-liver/kidney microsomal tpe 1 antibodies (anti-LKM1) in patients with chronic hepatitis C].

OBJECTIVE: To investigate the prevalence of antinuclear antibodies (ANA) and anti-liver/ kidney microsomal type 1 antibodies (anti-LKM1) in patients with chronic hepatitis C (CHC)and to explore the mechanism of production of these autoantibodies. METHODS: Serum samples were collected from 360 patients with CHC (case group), 69 patients with chronic hepatitis B (CHB) and 69 patients with autoimmune hepatitis (AIH) (control group). Serum ANA and anti-LKM1 were detected by indirect immunofluorescence (HF) technique and enzyme-linked immunosorbent assay (ELISA), respectively. Multi-factor analysis was performed to explore the correlations of the production of autoantibodies with some factors such as age, sex, viral loads, HCV genotype, biochemical parameters and clinical characteristics. RESULTS: Fifty-four (15%) of 360 patients infected with HCV were positive in autoantibodies. The prevalence of ANA and anti-LKM1 were 12.5% (45/360) and 2.5% (9/ 360), respectively. The positive rate of autoantibodies in patients with CHC was significantly higher than that in patients with CHB (15% vs 2.9%, P = 0.006), but significantly lower than that in patients with AIH (15% vs 47.9%, P < 0.001). Twenty-one (11.35%) of 185 male patients and 33 (18.86%) of 175 female patients were positive in autoantibodies, the difference in positive rate was significant (P < 0.05). HCV virus loads in the autoantibodies negative group were higher than that in the autoantibodies positive group (7.2 x 10(7) copies/L vs 1.23 x 10(7) copies/L, P < 0.05). There were not significant differences in age and genotype between the autoantibody positive group and the autoantibody negative group. The serum biochemical parameters of the autoantibody positive group were similar to those of the autoantibody negative group. The differences were not significant for the course of disease, clinical symptom, the incidence of cirrhosis between the autoantibody positive group and the autoantibody negative group. The prevalence of autoantibodies was not different for patients with or without interferon treatment (P > 0.05). CONCLUSION: Autoantibodies related to AIH can be detected in CHC patients; interferon may not induce the production of autoantibodies; it is very likely that HCV infection induces the autoimmune reaction and the production of autoantibodies.

Clinical relevance of anti-PR3 capture ELISA in diagnosing Wegener's granulomatosis.

Wegener's granulomatosis (WG) is one type of systemic small vessel vasculitis and antineutrophil cytoplasmic antibodies (ANCA) have become an established diagnostic tool for systemic vasculitis. The sensitivity and specificity of anti-PR3 (proteinase 3) capture enzyme-linked immunosorbent assay (ELISA) in diagnosing WG were investigated, as well as the correlation with the indirect immunofluorescence test (IIFT). Sera from 72 patients with WG, 100 disease controls, and 206 healthy blood donors were investigated for anti-PR3 and cytoplasmic ANCA (cANCA) by anti-PR3 classic ELISA, anti-PR3 capture ELISA, and IIFT. The sensitivity of anti-PR3 classic ELISA and capture ELISA in diagnosing WG was 74% and 87.5% separately. The specificity of the two ELISA was identical (100%). For the combination of IIFT with anti-PR3 capture ELISA, the sensitivity for WG patients was up to 91.6%. The sensitivity of anti-PR3 capture ELISA is superior to anti-PR3 classic ELISA, and the correlation between anti-PR3 capture ELISA and IIFT is also more superior. For suspected WG, anti-PR3 capture ELISA and IIFT should be applied in parallel.

[The correlation analysis of the reactive intensity of intradermal test for allergens and the concentration of specific IgE in serum].

OBJECTIVE: To explore the relationship between the reactive intensity of allergen intradermal test and the concentration of specific IgE (sIgE) in serum. METHOD: Intradermal test of six kinds of allergens was done in 192 cases of allergic rhinitis, including house dust, mite in powder and dust, poly mould, spring pollen, summer autumn pollen and Artemisia pollen. The serumic study of these kinds of allergens was also done with Pharmacia CAP system. RESULT: The total accordance rates of these six kinds of allergens with IgE in serum respectively are: house dust 65.93%, mite in powder and dust 68.1%, poly mould 55.6%, spring pollen 66.7%, summer autumn pollen 60.0% and Artemisia pollen 74.4%. The correlation index of them respectively are: house dust 0.4235 (P < 0.01), mite in powder and dust 0.4029(P < 0.01), poly mould 0.4932, spring pollen 0.3277 (P < 0.05), summer autumn pollen 0.2412 (P > 0.05) and Artemisia pollen 0.5000 (P < 0.01). CONCLUSION: The intradermal test of five kinds of allergens except for summer autumn pollen correlates with the concentration of IgE in serum.

Detection of antibodies against SARS-CoV in serum from SARS-infected donors with ELISA and Western blot.

Recombinant fragments of S proteins from the Severe Acute Respiratory Syndrome (SARS) coronavirus (SARA-CoV) were generated and used in a Western blot (WB) assay that was compared to a commercial SARS ELISA method. In 85% of confirmed SARS cases (n = 20), the S2 recombinant fragment based WB was positive and this was comparable to the commercial ELISA using heat killed SARS-CoV. WB using the other four recombinant fragments in confirmed SARS cases generated lower rates of detection (S1--75%, S1-N--25%, S1-C--55%). Evaluation of sera from healthy controls (n = 60) resulted in two weakly positive ELISA results with the remainder being negative while the S2 protein WB demonstrated three positive results from the 20 controls with a history of SARS contact and no positive results in 40 noncontact controls. A discrepancy between the ELISA and S2 WB arose when evaluating per-2003 sera from individuals (n = 10) with SARS-like symptoms (ELISA--100% positive, S2 WB--30% positive). These data suggest that the S2 WB assay may be particularly useful in ELISA-negative SARS cases and in some ELISA-positive non-SARS cases.