Diagnostic value of screening methods for the determination of antinuclear antibodies using indirect immunofluorescence on HEp-2 cells and enzyme immunoassay in autoimmune liver diseases.

Antinuclear antibodies (ANA) are a heterogeneous group of autoantibodies that react with various components of the cell nucleus and cytoplasm. ANA is the main serological marker for autoimmune liver disease (AILD). The aim of the study was to compare the diagnostic value of two methods of screening for the determination of ANA (indirect immunofluorescence reaction on HEp-2 cells (IIF -HEp-2) and enzyme-linked immunosorbent assay (ELISA) in the sera of AILD patients. The sera of 118 patients with AILD (51 with autoimmune hepatitis - AIH, 19 with primary biliary cholangitis - PBC, 48 with overlapping syndrome - OVERLAP), 30 patients with non-alcoholic fatty liver disease (NAFLD) and 30 healthy donors (HD) were studied. Determination of ANA by the IIF-HEp-2 method was carried out by visual assessment of samples under an AXIOSKOP 40 microscope, by ELISA - on an Alegria automatic analyzer. A weak degree of agreement between the positive and negative results of the ANA screening study using IIF-HEp-2 and ELISA (Cohen's kappa coefficient æ=0.4) was noted. Screening determination of ANA in patients with AILD by the IIF-HEp-2 method was distinguished by greater diagnostic sensitivity (DS) (68.6%) and a lower frequency of false negative results (31.4%) compared with ELISA (35.6% and 64.4 % respectively, p<0.05). The overall diagnostic specificity (DS) of the ANA study in IIF-HEp-2 was lower than with ELISA (66.7% and 86.7%, respectively, p<0.05). Both screening methods for determining ANA (IIF-HEp-2 and ELISA) were useful for diagnosing AILD (positive likelihood ratio - LR+: 2.1 and 2.6, respectively). In terms of the negative likelihood ratio (LR-), screening for ANA by the IIF-HEp-2 method, in contrast to ELISA, served as a "useful" test to exclude the diagnosis of AILD (0.5 and 0.8, respectively). The determination of ANA using IIF-HEp-2 is the most sensitive and "useful" screening test for the diagnosis of AILD, and ELISA is classified as a less "useful" screening method due to low diagnostic sensitivity and a high false-negative rate.

[Standardization of component manufacturing conditions and setting up the immunofluorescence reaction on the example of syphilis laboratory diagnostics (literature review).]

The use of technology for preparing components for immunofluorescence reaction (RIF) in a number of clinical diagnostic laboratories (CDL) in accordance with the recommendations of the Guidelines introduced by order of the RF Ministry of Health No 87 dated March 26, 2001 does not guarantee the required standardization of RIF preparation and conduct conditions. The latter is achieved by using the appropriate industrial production reagent kits in the СDL practice.

[Epstein-Barr virus (Herpesviridae: Lymphocryptovirus) types 1 and 2 and other viral markers in patients with nasopharyngeal carcinoma in two geographically and ethnically distinct regions of Russia].

INTRODUCTION: The discovery of two types of Epstein-Barr virus (EBV) (EBV-1 and EBV-2) that have different biological properties stimulated the search for neoplasms associated with each type of the virus. The aim of the work is to study the nature of the association of nasopharyngeal cancer (NPC) with EBV-1 and EBV-2, serological activity for each viral type and the concentration of EBV DNA in the blood plasma of two gender, age and ethnic groups of NPC patients that represent geographically and climatically different regions of Russia,. MATERIALS AND METHODS: In the blood plasma of patients with NPC and other non- EBV associated tumors of oral cavity (OTOCEBV-) from the North Caucasian (NCFD) and Central (CFD) Federal Districts of Russia, the types of EBV and the concentration of viral DNA were determined using respectively «nested¼ and real time PCR; titers of IgG and IgA antibodies to viral capsid antigen (VCA) were measured in indirect immunofluorescence assay. RESULTS: The blood plasma samples testing showed that NPC and OTOCEBV- patients were infected with both types of EBV in approximately equal proportions. In two groups of NPC patients infected with one of the virus types only, EBV-1 or EBV-2, respectively, no statistically significant differences were found between the geometric mean values of IgG and IgA anti-EBV antibody titers and viral DNA concentrations in blood plasma. The distribution of virus types was not affected by either patient gender or ethnogeographic origin. The difference was found only between age groups: EBV-2 dominated in NPC patients up to 60 years, and EBV-1 was prevalent in patients over 60 years. CONCLUSION: The lack of the predominance of one of EBV types in NPC patients that are the representatives of different ethnic groups from geographically and climatically different regions, suggests that none of these factors play an important role in the NPC carcinogenesis. Evidently, each type of EBV, EBV-1 or EBV-2, if the necessary conditions arise, are able to exhibit its oncogenic potential to initiate tumor development.

Occurrence of anti-Neospora caninum antibodies in cattle in the dairy farming region of the state of Piauí, Brazil / Ocorrência de anticorpos anti- Neospora caninum em vacas na bacia leiteira do estado do Piauí, Brasil

Abstract This study focused on the detection of anti-Neospora caninum IgG antibodies in cows in the dairy farming region of the state of Piauí, Brazil. To this end, serum samples were collected from 255 dairy cows on 17 farms located in the dairy farming region of the municipality of Parnaíba, Piauí, Brazil. The indirect fluorescence antibody test (IFAT) was employed to detect anti-N. caninum IgG antibodies, using anti-bovine IgG (Sigma®) conjugated to fluorescein isothiocyanate (FITC) and a cutoff point of 1:200. Of the 255 samples analyzed, 69 (27.06%) were positive for anti- N. caninum IgG antibodies, the relative frequency found by property was: 1 (20.00%), 2 (53.33%), 3 (46.66%), 4 (53.33%), 5 (26.66%), 6 (6.66%), 7 (6.66%), 8 (20.00%), 9 (26.66%), 10 (26.66%), 11 (20.00%), 12 (20.00%), 13 (46.66%), 14 (26.66%), 15 (26.66%), 16 (20.00%) and 17 (13.33%). with titers of 200 (15.94%), 400 (20.30%), 800 (24.63%), 1600 (23.18%) and 3200 (15.94%), being the highest frequency for the titer of 800. This study demonstrates for the first time that cows from dairy herds of Parnaíba municipality, state of Piauí, are exposed to N. caninum.

Resumo Objetivou-se estudar a ocorrência de anticorpos IgG anti- Neospora caninum em vacas, na bacia leiteira do estado do Piauí, Brasil. Foram obtidas amostras séricas de 255 vacas leiteiras provenientes de 17 propriedades localizadas na bacia leiteira do município de Parnaíba, Piauí, Brasil. Para a pesquisa de anticorpos IgG anti- N. caninum foi empregada a técnica de Reação de Imunofluorescência Indireta, utilizando-se conjugado anti-IgG bovine (Sigma®) conjugado ao isotiocianato de fluoresceína e ponto de corte 1:200. Das 255 amostras analisadas, 69 (27,06%) foram positivas para anticorpos IgG anti- N. caninum, a frequência relativa encontrada por propriedade foi de: 1 (20,00%), 2 (53,33%), 3 (46,66%), 4 (53,33%), 5 (26,66%), 6 (6,66%), 7 (6,66%), 8 (20,00%), 9 (26,66%) 10 (26,66%), 11 (20,00%), 12 (20,00%), 13 (46,66%), 14 (26,66%), 15 (26,66%), 16 (20,00%) e 17 (13,33%) com títulos de 200 (15,94%), 400 (20,30%), 800 (24,63%), 1600 (23,18%) e 3200 (15,94%), sendo a maior frequência para o título de 800. Este estudo demonstra pela primeira vez que, vacas de rebanhos leiteiros do município de Parnaíba, estado do Piauí, estão expostas ao N. caninum.

Occurrence of anti-Neospora caninum antibodies in cattle in the dairy farming region of the state of Piauí, Brazil

Abstract This study focused on the detection of anti-Neospora caninum IgG antibodies in cows in the dairy farming region of the state of Piauí, Brazil. To this end, serum samples were collected from 255 dairy cows on 17 farms located in the dairy farming region of the municipality of Parnaíba, Piauí, Brazil. The indirect fluorescence antibody test (IFAT) was employed to detect anti-N. caninum IgG antibodies, using anti-bovine IgG (Sigma®) conjugated to fluorescein isothiocyanate (FITC) and a cutoff point of 1:200. Of the 255 samples analyzed, 69 (27.06%) were positive for anti- N. caninum IgG antibodies, the relative frequency found by property was: 1 (20.00%), 2 (53.33%), 3 (46.66%), 4 (53.33%), 5 (26.66%), 6 (6.66%), 7 (6.66%), 8 (20.00%), 9 (26.66%), 10 (26.66%), 11 (20.00%), 12 (20.00%), 13 (46.66%), 14 (26.66%), 15 (26.66%), 16 (20.00%) and 17 (13.33%). with titers of 200 (15.94%), 400 (20.30%), 800 (24.63%), 1600 (23.18%) and 3200 (15.94%), being the highest frequency for the titer of 800. This study demonstrates for the first time that cows from dairy herds of Parnaíba municipality, state of Piauí, are exposed to N. caninum.

Resumo Objetivou-se estudar a ocorrência de anticorpos IgG anti- Neospora caninum em vacas, na bacia leiteira do estado do Piauí, Brasil. Foram obtidas amostras séricas de 255 vacas leiteiras provenientes de 17 propriedades localizadas na bacia leiteira do município de Parnaíba, Piauí, Brasil. Para a pesquisa de anticorpos IgG anti- N. caninum foi empregada a técnica de Reação de Imunofluorescência Indireta, utilizando-se conjugado anti-IgG bovine (Sigma®) conjugado ao isotiocianato de fluoresceína e ponto de corte 1:200. Das 255 amostras analisadas, 69 (27,06%) foram positivas para anticorpos IgG anti- N. caninum, a frequência relativa encontrada por propriedade foi de: 1 (20,00%), 2 (53,33%), 3 (46,66%), 4 (53,33%), 5 (26,66%), 6 (6,66%), 7 (6,66%), 8 (20,00%), 9 (26,66%) 10 (26,66%), 11 (20,00%), 12 (20,00%), 13 (46,66%), 14 (26,66%), 15 (26,66%), 16 (20,00%) e 17 (13,33%) com títulos de 200 (15,94%), 400 (20,30%), 800 (24,63%), 1600 (23,18%) e 3200 (15,94%), sendo a maior frequência para o título de 800. Este estudo demonstra pela primeira vez que, vacas de rebanhos leiteiros do município de Parnaíba, estado do Piauí, estão expostas ao N. caninum.