To explore the clinical diagnostic efficacy of antineutrophil cytoplasmic antibody associated vasculitis (AAV) by comparing the consistency and coincidence rate of serum anti-myeloperoxidase (MPO) antibody and anti-protease 3 (PR3) antibody detected by digital liquid chip method (DLCM) and enzyme-linked immunosorbent assay (ELISA). To provide reference for the selection of detection methods of anti-MPO antibody and anti-PR3 antibody in clinical laboratory. This study is a cross-sectional study, a total of 307 cases of antineutrophil cytoplasmic antibodies were detected in the Department of Clinical Immunology, West China Hospital of Sichuan University from January to March 2021. The serum samples and related clinical information were collected. At the same time, the levels of anti-MPO antibody and anti-PR3 antibody in serum samples were detected by ELISA and DLCM, indirect immunofluorescence (IIF) was used to re-test the differential samples between the two methods. SPSS 26.0 was used to analyze the test results, Cohen's kappa coefficient analysis was used to compare the consistency of the two methods, and paired chi-square test was used to compare the sensitivity and specificity of the two methods to AAV. The results showed that the positive cases of anti-MPO antibody detected by ELISA and DLCM were 63 and 44, and the negative cases were 244 and 263; the positive cases of anti-PR3 antibody detected by ELISA and DLCM were 34 and 28, and the negative cases were 273 and 279. The results of anti-MPO antibody and anti-PR3 antibody detected by the two methods had good consistency and coincidence rate, in which the total coincidence rate of anti-MPO antibody was 92.51%, the positive coincidence rate was 66.67%, and the negative coincidence rate was 99.18%. The results of consistency analysis showed that kappa=0.741 had well consistency. The total coincidence rate of anti-PR3 antibody is 96.74%, the positive coincidence rate is 76.47%, and the negative coincidence rate is 99.27%. The consistency analysis results show that kappa=0.821 had strong consistency. The results of IIF re-test of differential samples showed that the coincidence rate between DLCM and IIF was higher. The results of comparative analysis of anti-MPO antibody and anti-PR3 antibody showed that the specificity of DLCM was better than that of ELISA, and its sensitivity was lower than that of ELISA. In conclusion, the results of anti-MPO antibody and anti-PR3 antibody detected by DLCM were consistent with those of ELISA. In the combined detection of anti-MPO antibody and anti-PR3 antibody, the specificity of DLCM is better than that of ELISA.
Humans ; Antibodies, Antineutrophil Cytoplasmic/analysis* ; Myeloblastin ; Cross-Sectional Studies ; Sensitivity and Specificity ; Fluorescent Antibody Technique, Indirect ; Enzyme-Linked Immunosorbent Assay/methods*

BACKGROUND AND PURPOSE: Cutaneous nerve biopsies based on two-dimensional analysis have been regarded as a creditable assessment tool for diagnosing peripheral neuropathies. However, advancements in methodological imaging are required for the analysis of intact structures of peripheral nerve fibers. A tissue-clearing and labeling technique facilitates three-dimensional imaging of internal structures in unsectioned, whole biological tissues without excessive time or labor costs. We sought to establish whether a tissue-clearing and labeling technique could be used for the diagnostic evaluation of peripheral neuropathies. METHODS: Five healthy individuals and four patients with small-fiber neuropathy (SFN) and postherpetic neuralgia (PHN) were prospectively enrolled. The conventional methods of indirect immunofluorescence (IF) and bright-field immunohistochemistry (IHC) were adopted in addition to the tissue-clearing and labeling method called active clarity technique-pressure related efficient and stable transfer of macromolecules into organs (ACT-PRESTO) to quantify the intraepidermal nerve-fiber density (IENFD). RESULTS: The mean IENFD values obtained by IF, bright-field IHC, and ACT-PRESTO in the healthy control group were 6.54, 6.44, and 90.19 fibers/mm², respectively; the corresponding values in the patients with SFN were 1.99, 2.32, and 48.12 fibers/mm², respectively, and 3.06, 2.87, and 47.21 fibers/mm², respectively, in the patients with PHN. CONCLUSIONS: This study has shown that a tissue-clearing method provided not only rapid and highly reproducible three-dimensional images of cutaneous nerve fibers but also yielded reliable quantitative IENFD data. Quantification of the IENFD using a tissue-clearing and labeling technique is a promising way to improve conventional cutaneous nerve biopsies.
Biopsy ; Fluorescent Antibody Technique, Indirect ; Humans ; Imaging, Three-Dimensional ; Immunohistochemistry ; Methods ; Nerve Fibers ; Neuralgia, Postherpetic ; Peripheral Nerves ; Peripheral Nervous System Diseases ; Prospective Studies

OBJECTIVETo analyze clinical manifestations, treatment and prognosis of 4 cases with endemic typhus.

METHODThe clinical data of four endemic typhus patients in prognosis were retrospectively analyzed. These four atypical cases of endemic typhus with pneumonia were treated in our department from October 2011 to March 2012. They were all male, with an age range of 15 months to 7 years. The four patients had long history, mild respiratory symptom and no improvement was found after treatment with cephalosporins. There were no evidences of bacterial, viral, or fungal infections and we thought they might have infection with other pathogen. Three were from rural areas. Routine blood tests, Weil-Felix reaction, blood smear (Giemsa staining) , and indirect immunofluorescence assay were performed.

RESULTBlood smear and IFA tests showed evidences for endemic typhus. The clinical presentations were atypical, the patients had no headache, but all had fever, rash, and pneumonia of varying severity. None of the patients had a severe cough, but bronchial casts were observed in one case. Recurrent fever was reported in three cases. Physical examinations showed no eschars, but one patient had a subconjunctival hemorrhage, and one had skin scratches, cervical lymphadenopathy, pleural effusion, pericardial effusion, and cardiac dilatation. Two patients had remarkably increased peripheral blood leukocyte counts; both these patients also had high alanine aminotransferase (ALT) levels and one had a high C-reactive protein (CRP) level. Weil-Felix testing was negative or the OX19 titer was low. The peripheral blood smear (Giemsa stain) showed intracellular pathogens in all four cases. After combined therapy with doxycycline and macrolide antibiotics, all four patients recovered well.

CONCLUSIONThe endemic typhus children often come from rural areas. The clinical presentations were atypical, they usually have no headache, but have fever (often Periodic fever) , rash, and pneumonia of varying severity in these four cases. Combined therapy with doxycycline and macrolide antibiotics was effective in all four patients.

Anti-Bacterial Agents ; therapeutic use ; Child ; Child, Preschool ; Doxycycline ; therapeutic use ; Fever ; diagnosis ; drug therapy ; pathology ; Fluorescent Antibody Technique, Indirect ; Humans ; Infant ; Leukocyte Count ; Lung ; diagnostic imaging ; pathology ; Macrolides ; therapeutic use ; Male ; Pneumonia ; diagnosis ; drug therapy ; pathology ; Radiography ; Retrospective Studies ; Staining and Labeling ; methods ; Typhus, Endemic Flea-Borne ; diagnosis ; drug therapy ; pathology

Serum samples, 100 in the total number, were collected from different laboratories in Tehran, Iran and tested for anti-Toxoplasma specific IgG and IgM antibodies using indirect immunofluorescent antibody test (IFAT). Using the IgG (chronic) and IgM (acute) positive samples, the IgG avidity test was performed by ELISA in duplicate rows of 96-well microtiter plates. One row was washed with 6 M urea and the other with PBS (pH 7.2), then the avidity index (AI) was calculated. Sixteen out of 18 (88.9%) sera with acute toxoplasmosis showed low avidity levels (AI< or =50), and 76 out of 82 (92.7%) sera in chronic phase of infection showed high avidity index (AI>60). Six sera had borderline ranges of AI. The results showed that the IgG avidity test by ELISA could distinguish the acute and chronic stages of toxoplasmosis in humans.
Antibodies, Protozoan/*blood ; *Antibody Affinity ; Clinical Laboratory Techniques/*methods ; Enzyme-Linked Immunosorbent Assay/methods ; Fluorescent Antibody Technique, Indirect ; Humans ; Immunoglobulin G/*blood ; Immunoglobulin M/blood ; Iran ; Parasitology/*methods ; Toxoplasmosis/*diagnosis

Serum samples, 100 in the total number, were collected from different laboratories in Tehran, Iran and tested for anti-Toxoplasma specific IgG and IgM antibodies using indirect immunofluorescent antibody test (IFAT). Using the IgG (chronic) and IgM (acute) positive samples, the IgG avidity test was performed by ELISA in duplicate rows of 96-well microtiter plates. One row was washed with 6 M urea and the other with PBS (pH 7.2), then the avidity index (AI) was calculated. Sixteen out of 18 (88.9%) sera with acute toxoplasmosis showed low avidity levels (AI< or =50), and 76 out of 82 (92.7%) sera in chronic phase of infection showed high avidity index (AI>60). Six sera had borderline ranges of AI. The results showed that the IgG avidity test by ELISA could distinguish the acute and chronic stages of toxoplasmosis in humans.
Antibodies, Protozoan/*blood ; *Antibody Affinity ; Clinical Laboratory Techniques/*methods ; Enzyme-Linked Immunosorbent Assay/methods ; Fluorescent Antibody Technique, Indirect ; Humans ; Immunoglobulin G/*blood ; Immunoglobulin M/blood ; Iran ; Parasitology/*methods ; Toxoplasmosis/*diagnosis

OBJECTIVETo evaluate the Anaplasma phagocytophilum (A. phagocytophilum), Ehrlichia canis (E. canis), Dirofilaria immitis (D. immitis) (canine heartworm), Borrelia burgdorferi (B. burgdorferi) infections in countryside dogs from Yunnan, Hainan and Anhui provinces.

METHODSSerum samples were collected from 26 dogs in Yunnan, Hainan and Anhui provinces. The samples were tested using a commercial ELISA rapid diagnostic assay kit (SNAP(®) 4Dx(®); IDEXX Laboratories, Inc. U.S.A.). Meanwhile, indirect immunofluorescence assay (IFA) recommended by WHO was conducted to detect IgG to A. phagocytophilum. Two methods were analyzed and compared.

RESULTSThe number of serologically positive dogs for IgG to A. phagocytophilum was only 2 which was from Hainan province and none of the 26 dogs responded positive for E. canis, D. immitis (canine heartworm), and B. burgdorferi by ELISA rapid diagnostic method. The number of serologically positive dogs for IgG to A. phagocytophilum was 13 (50%) by IFA method. Data of the two methods were analyzed by statistical software and the difference was statistically significant (P=0.002).

CONCLUSIONSIt can be concluded that IFA method was more sensitive than ELISA rapid diagnostic method. However, we need conduct further and intensive epidemiology survey on tick-born diseases pathogens including A. phagocytophilum, E. canis, D. immitis (canine heartworm), and B. burgdorferi which have public health significance.

Anaplasma phagocytophilum ; immunology ; Animals ; Borrelia burgdorferi ; immunology ; China ; epidemiology ; Dirofilaria immitis ; immunology ; Dirofilariasis ; blood ; epidemiology ; immunology ; Disease Vectors ; Dog Diseases ; epidemiology ; Dogs ; Ehrlichia canis ; immunology ; Ehrlichiosis ; blood ; epidemiology ; immunology ; Enzyme-Linked Immunosorbent Assay ; methods ; Fluorescent Antibody Technique, Indirect ; methods ; Immunoglobulin G ; blood ; Lyme Disease ; blood ; epidemiology ; immunology ; Tick-Borne Diseases ; epidemiology

To study the correlation between ELISA and IFA tests in detection of ALV-A/B antibody in chicken sera, ELSA S/P values and IFA titers for different serum samples were measured and statistically analyzed. The results indicated that there was a strong positive correlation between ELISA S/P values and IFA titers (r = 0.97435, P < 0.001). Because the positive correlation between ELISA and IFA was so strong and antibody positive rates were identical in two tests, it suggested that IFA could be used as a alternative method to replace ELISA kit when only limited numbers of samples to be tested to reduce the cost and increase the sensitivity.
Animals ; Antibodies, Viral ; blood ; immunology ; Avian Leukosis ; diagnosis ; immunology ; virology ; Avian Leukosis Virus ; classification ; immunology ; isolation & purification ; Cell Line ; Chickens ; Enzyme-Linked Immunosorbent Assay ; methods ; Fluorescent Antibody Technique, Indirect ; methods ; Poultry Diseases ; diagnosis ; immunology ; virology ; Species Specificity

The integrity and transparency of cornea plays a key role in vision. Limbal Stem Cells (LSCs) are precursors of cornea, which are responsible for self-renewal and replenishing corneal epithelium. Though it is successful to cell replacement therapy for impairing ocular surface by Limbal Stem Cell Transplantation (LSCT), the mechanism of renew is unclear after LSCT. To real time follow-up the migration and differentiation of corneal transplanted epithelial cells after transplanting, we transfected venus (a fluorescent protein gene) into goat LSCs, selected with G418 and established a stable transfected cell line, named GLSC-V. These cells showed green fluorescence, and which could maintain for at least 3 months. GLSC-V also were positive for anti-P63 and anti-Integrinbeta1 antibody by immunofluorescent staining. We founded neither GLSC-V nor GLSCs expressed keratin3 (k3) and keratinl2 (k12). However, GLSC-V had higher levels in expression of p63, pcna and venus compared with GLSCs. Further, we cultivated the cells on denude amniotic membrane to construct tissue engineered fluorescent corneal epithelial sheets. Histology and HE staining showed that the constructed fluorescent corneal epithelial sheets consisted of 5-6 layers of epithelium. Only the lowest basal cells of fluorescent corneal epithelial sheets expressed P63 analyzed by immunofluorescence, but not superficial epithelial cells. These results showed that our constructed fluorescent corneal epithelial sheets were similar to the normal corneal epithelium in structure and morphology. This demonstrated that they could be transplanted for patents with corneal impair, also may provide a foundation for the study on the mechanisms of corneal epithelial cell regeneration after LSCT.
Animals ; Cell Culture Techniques ; methods ; Cell Line ; cytology ; Epithelium, Corneal ; cytology ; metabolism ; Fluorescent Antibody Technique, Indirect ; Goats ; Limbus Corneae ; cytology ; Stem Cell Transplantation ; Stem Cells ; cytology

BACKGROUND: Dense fine speckled (DFS) pattern in antinuclear antibody (ANA) test using indirect immunofluorescence method became to be known recently and it is detected in patients with various chronic inflammatory diseases as well as in healthy individuals. We investigated the relation between DFS pattern and various diseases. METHODS: ANA tests by indirect immunofluorescence method using HEp-2 cell line slide (Kallestad; Bio-Rad, USA) were performed in 2,654 patients for screening of systemic autoimmune diseases. The frequencies of ANA and DFS positivity were analyzed according to sex, age, clinical department and disease. RESULTS: ANA was positive in 13.3% (352/2,654) of the total patients, and the frequency of DFS pattern was observed in 3.8% (101/2,654) of the total patients and in 28.7% (101/352) of the patients with ANA positivity. Higher frequency of DFS positivity was observed in patients referred from Departments of Rheumatology and Nephrology, but there was no difference in the frequencies of DFS positivity among the patients with ANA positivity. The frequency of DFS pattern was higher in seborrheic dermatitis (14.3%), herpes zoster (11.1%), rheumatoid arthritis (16.9%), systemic lupus erythematosus (15.4%) and Sjogren syndrome (14.3%). CONCLUSIONS: The DFS pattern is a frequent finding (about 28% of ANA positivity) in ANA test using indirect immunofluorescence method. Relatively high frequency of DFS pattern was observed in autoimmune diseases, contrary to the previous observations that DFS pattern is not related with autoimmune diseases. Further studies including the confirmation tests of anti-DFS70 are needed for the identification of relation between DFS pattern and particular diseases.
Adaptor Proteins, Signal Transducing/immunology ; Adolescent ; Adult ; Aged ; Antibodies, Antinuclear/*blood/diagnostic use ; Arthritis, Rheumatoid/immunology ; Child ; Child, Preschool ; Female ; Fluorescent Antibody Technique, Indirect/*methods ; Humans ; Infant ; Male ; Middle Aged ; Retrospective Studies ; Transcription Factors/immunology

OBJECTIVETo establish a method of indirect immunofluorescence (IIF) to measure DNA (mDNA)-associated autoantibodies to cell membrane, and to evaluate diagnostic value of the anti-mDNA antibodies in patients with juvenile systemic lupus erythematosus (SLE) in comparison with anti-dsDNA antibody.

METHODSForty-four children with SLE were enrolled in this study. As a control group, 30 children with other rheumatic diseases were also enrolled. Anti-mDNA and anti-dsDNA antibodies were measured by IIF. Anti-smooth muscle (Sm) antibodies were measured by immuno-double diffusion (ID) and IIF.

RESULTSOut of 44 juvenile SLE patients, 34 (77.27%) were seropositive for anti-mDNA, which was significantly higher than that of patients with other rheumatic diseases (20.00%, P<0.05). The sensitivity and specificity of anti-mDNA for juvenile SLE diagnosis were 77.27% and 80.00%, respectively. The positive predictive value and negative predictive value were 85.00% and 70.59%, respectively. The positive rate of anti-mDNA in SLE lacking of anti-dsDNA and anti-Sm antibodies were 68.00% (17/25) and 79.49% (31/39), respectively.

CONCLUSIONThe detection of anti-mDNA antibodies is useful for diagnosis of juvenile SLE, especially in patients who are negative for anti-dsDNA antibodies and anti-Sm antibodies.

Adolescent ; Antibodies, Antinuclear ; analysis ; Case-Control Studies ; Cell Membrane ; immunology ; Child ; Female ; Fluorescent Antibody Technique, Indirect ; methods ; Humans ; Lupus Erythematosus, Systemic ; immunology ; Male ; Predictive Value of Tests ; Sensitivity and Specificity