[en] The article reviews principles, requirements and reliability criteria of radioimmunoassay (RIA). Since basic reactions involved in RIA and related techniques are derived from reactions which take place in the immune system (IS) of humans and animals, the IS and the way it works will be described. In addition to RIA which involves the use of isotopes as tracers (labels), other non-radioisotopic and recent immunoassay techniques i.e. enzyme-linked immunosorbent assay (ELISA), chemiluminescence immunoassay (CLIA) and fluoroimmunoassay (FIA) will be dealt with. Some important and related terms will be defined and explained. (author). 59 refs., 4 figs

[en] A list of products of URVJT (Institute of Radioecology and Application of Nuclear Techniques) in Kosice is given. It includes RIA diagnostic kits, RIA radioindicators, ELISA kits, and OKB diagnostic kits. (Z.S)

[en] The determination of thyrotropin(TSH) is useful in diagnosis of thyroid diseases. And the widely-used method for the determination of thyrotropin is radioimmunoassay so far because of its sensitivity. But its radiohazard and relatively short half-life of isotopes necessitates alternative methods. So many novel non-isotopic immunoassays are developed and now replacing RIA in routine laboratory measurements. We evaluated the enhanced chemiluminescence enzymeimmunoassay (Amerlite, Amersham International plc., U.K.) for the determination of serum TSH. We got good precision result with control sera. Within-assay and between-assay precision revealed less than 10%(C.V.) respectively. And comparision with CLEIA to RIA showed good correlation (y=0.648x + 0.170, r=0.978, y=value of CLEIA, x=values of RIA, n=35). We also got good correlation between singletons and duplicates result from 35 patients sera (y=0.967x + 0.0281, r=0.997, y=values of singletons, x=values of duplicates). We concluded that CLEIA is vary reliable and economic method for the determination of human TSH substitutive for RIA because of its precision and unnecessary duplicate measurements. (Author)

[en] Primary biliary cirrhosis (PBC) is a chronic and slowly progressive cholestatic liver disease of autoimmune etiology. A number of questions regarding its etiology are unclear. CD4+CD25+ regulatory T cells (Tregs) play a critical role in self-tolerance and, for unknown reasons, their relative number is reduced in PBC patients. B-cell-activating factor (BAFF) is a key survival factor during B-cell maturation and its concentration is increased in peripheral blood of PBC patients. It has been reported that activated B cells inhibit Treg cell proliferation and there are no BAFF receptors on Tregs. Therefore, we speculated that excessive BAFF may result in Treg reduction via B cells. To prove our hypothesis, we isolated Tregs and B cells from PBC and healthy donors. BAFF and IgM concentrations were then analyzed by ELISA and CD40, CD80, CD86, IL-10, and TGF-β expression in B cells and Tregs were measured by flow cytometry. BAFF up-regulated CD40, CD80, CD86, and IgM expression in B cells. However, BAFF had no direct effect on Treg cell apoptosis and cytokine secretion. Nonetheless, we observed that BAFF-activated B cells could induce Treg cell apoptosis and reduce IL-10 and TGF-β expression. We also showed that BAFF-activated CD4+ T cells had no effect on Treg apoptosis. Furthermore, we verified that bezafibrate, a hypolipidemic drug, can inhibit BAFF-induced Treg cell apoptosis. In conclusion, BAFF promotes Treg cell apoptosis and inhibits cytokine production by activating B cells in PBC patients. The results of this study suggest that inhibition of BAFF activation is a strategy for PBC treatment

[en] Recently, it is found that T-helper (Th) 22 cells are involved in different types of autoimmune and tumor diseases. But, till now, no study has been carried out to understand the involvement of these cells in cervical cancer (CC). Flow cytometry was used to determine the expression of interferon gamma (IFN-γ), Interleukin-22 (IL-22), IL-17 in the peripheral blood of healthy controls (HC), CIN and cervical cancer patients. From peripheral blood mononuclear cells (PBMCs), mRNA expression levels of Aryl hydrocarbon receptor (AHR), RAR-related orphan receptor C (RORC), TNF-α and IL-6 were respectively determined. Using the method of ELISA, plasma concentrations of IL-22, IL-17 and TNF-α were examined. Th22 and Th17 cells were elevated in CC and CIN patients. Th1 cells and the plasma concentrations of IL-22 in CC patients were significantly increased compared with HC. In CC patients, an increased prevalence of Th22 cells was associated with lymph node metastases. There was a positive correlation between Th22 and Th17 cells, but an approximately negative correlation between Th22 and Th1 cells in CC patients. The mRNA expression of RORC, TNF-α and IL-6 was significantly high in CC patients. Our results indicate that there is a higher circulatory frequency of Th22, Th17 and Th1 cells in CC which may conjointly participate in the pathogenesis and growth of CC

[en] The authors studies 23 chronic carriers of HBsAg, to classify them in terms of sorology, histopathologic findings and behaviour of markers HBsAg and HBcAg in hepatic tissue. Immunohistochemical techniques were used to establish possible relations between these parameters. Among patients with positive HBeAg found all exhibited HBcAg in hepatic tissue, but in 16 patients in which HBeAg was negative, liver HBcAg was positive in 3 cases (18.7%). No correlation was found between the HBeAg system/anti-HBe and histopathologic findings because chronic active hepatitis was observed in 6/8 anti-HBe positive patients (75%). These findings suggest that, the evaluation of chronic carriers of HBsAg, requires a histologic analysis of the liver, including a tissue research for the virus in addition to a complete sorologic study of HBV. (author)

[en] To asses the efficacy of commercially available tests device method for anti HCV detection. Methods: Total 2000 blood samples for detection of anti HCV were screened initially by immuno chromatographic method. Those found positive on initial screening were re-tested by ELISA method at the Biochemistry Laboratory of the Pakistan Medical Research Council, Fatima Jinnah Medical College, Lahore. Results: Out of a total of 2,000 blood samples, 177 were found to be initially reactive/positive for anti-HCV with immuno chromatographic method. When these reactive/positive samples were retested for confirmation with ELISA, 47 blood samples were found to have tested falsely positive for anti-HCV. Overall 2.35% of blood samples were found to be tested false positive for anti-HCV by immuno chromatographic device method. Conclusions: Immuno chromatographic device method test is rapid and simple, which can be used in setting with limited facility when rapid testing is required. However it should not be used as sole criteria for diagnosis but should serve the purpose of initial screening only. Further research is required to establish the reliability of such devices for their specificity and sensitivity. (author)

[en] Objective: To assess the prevalence of anti HCV antibodies in blood donors. Design: The retrospective sero-epidemiological data of the institute of Hematology and Blood Transfusion Service, Punjab over a period of one year after starting HCV screening, was analyzed to estimate the percentage prevalence. Setting; The data was obtained regularly from the blood units established by this institute at the pablic sector hospitals and retesting on initially reactive serum sample by EIA was done at the Institute. Subjects: A total of 166183 directed first time donors or replacement blood donors aged 18-60 years who donated blood at these blood banks or at mobile sessions have been included in the study. All initially reactive donors who tested non-reactive on EIA were excluded from the study. Main outcome Measures: Assessment of prevalence of HCV in blood donors. Results: 4.45% of the total donors intially tested reactive of these 0.36 % were atsety reactive on intial screening. Further testing by EIA, 4.1%. Conclusions: The blood transfusion service started screening for HCV in April 2000 and the prevalence of HCV, amongst the transfusion transmitted infections (TTIs) being screened for in the Punjab, is the highest. It is almost double the prevalence of HBV and several thousand time that of HIV. Meticulous and total screening coverage is needed to curtail impending catastrophe. With experience, the choice of testing methodology might have to be reviewed. (author)

[en] Th17 cells are involved in liver fibrosis by activating hepatic stellate cells (HSCs). We aimed to investigate whether HSCs are able to regulate the function of Th17 cells and to determine the relevant mechanism. Sixty-five patients diagnosed with chronic hepatitis B (CHB) were enrolled in this study. To determine the effect of HSCs on T cells, naïve CD4⁺T cells and Th17 cells were sorted from CHB patients and cultured with or without activated-HSCs, and cytokine expression and gene transcription were analyzed. In addition, the regulatory mechanism of HSCs was investigated. ELISA and qRT-PCR showed that Th17 cells from CHB patients were more pathogenic, on the basis of the expression of IL-17A, IL-23R, RORC, CCL20 and CCR6, and meanwhile, they could activate the primary HSCs. Co-culture experiments indicated that activated HSCs dramatically promoted proliferation of CD4⁺T cells in a time- and dose-dependent manner. In addition, they could induce naïve CD4⁺T cells to become Th17 cells which had a more pathogenic phenotype. Moreover, activated HSCs-mediated induction of Th17 cells might depend on the release of IL-1β and IL-6 as well as on the COX-PGE2 pathway. Th17 cells cooperated with HSCs in a proinflammatory feedback loop might provide a better understanding of the pathogenic role of Th17 cells in the chronicity of HBV infection. - Highlights: • Th17 cells from CHB patients promoted the activation of primary HSCs. • Activated HSCs induced Th17 cells which displayed a pathogenic phenotype. • The induction of Th17 cells by activated HSCs depended on IL-1β and IL-6 release as well as on the COX-PGE2 pathway.

[en] Transmission of HIV-1 from an infected mother to her infant is the major route of transmission of this infection to children. In sub-Saharan Africa where heterosexual transmission of HIV is the commonest mode of spread, high prevalence of HIV infection in women of child bearing age is bound to lead to increased paediatric AIDS as a result of vertical transmission. In recognizing these epidemiological factors, the University of Nairobi HIV-1 Perinatal Transmission and Paediatric AIDS Project was initiated in 1986. Antenatal mothers attending Pumwani Maternity Hospital were enrolled during labour and screened for HIV-1 infection by ELISA. Those reacting positive were to participate in the study. An equal number of negative controls were also recruited. The mothers and babies of both groups were followed for varying periods over the next five years. A total of 360 babies born to HIV infected mothers and 360 babies born to HIV negative mothers were examined. The mortality rate observed in the HIV-1 exposed was substantially higher than that observed in controls (RR 2.8, 95% CI 1.3-6.1). Common causes of death among infected infants were pneumonia, measles, malaria, gastroenteritis, tuberculosis, and septicaemia. The five year survival was 85% among HIV infected children. Maternal risk factors associated with transmission were marital status, duration of sexual activity and the age of the first intercourse