ABSTRACT
<p><b>OBJECTIVE</b>To prepare artificial antigens and anti-citrinin egg yolk-derived immunoglobulin (IgY) to build an enzyme-linked immunosorbent assay (ELISA) for citrinin (CTN).</p><p><b>METHODS</b>CTN was conjugated with bovine serum albumin (BSA), ovalbumin (OVA) with formaldehyde condensation method to prepare artificial antigens and identified by ultraviolet (UV) spectrometry and Infrared (IR) spectrometry. Artificial antigens for CTN and anti-CTN IgY were purified with polyethylene glycol two-step precipitation method and identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). ELISA with IgY was established. Cross-reactivity of IgY with various structural similarities to CTN and possible co-occurrence with CTN in agricultural commodities were studied.</p><p><b>RESULTS</b>UV and IR absorption spectra suggested that CTN was correlated with the carrier protein of BSA or OVA. SDS-PAGE patterns showed that the anti-CTN IgY was almost pure with a molecular weight of approximate 100 KD. The indirect competitive ELISA showed that the detection limit of CTN was 10 ng x mL(-1), with a good linearity ranging 20-640 ng x mL(-1).</p><p><b>CONCLUSION</b>Artificial antigens of CTN can be successfully synthesized. The established ELISA can be used to determine CTN- contaminated samples.</p>
Subject(s)
Animals , Female , Antibody Specificity , Antigens , Chemistry , Chickens , Citrinin , Chemistry , Egg Yolk , Allergy and Immunology , Enzyme-Linked Immunosorbent Assay , Methods , Immunoglobulins , Allergy and ImmunologyABSTRACT
<p><b>OBJECTIVE</b>To explore the change of T cell subsets in patients suffered from hepatocellular carcinoma (HCC) before and after hepatectomy, and study the value of Roferon-A (interferon alpha-2a) combined with hepatic artery chemoembolization (HACE) and portal vein chemotherapy (PVC) after radical resection of HCC for preventing recurrence.</p><p><b>METHODS</b>On 75 HCC patients, PVC and HACE were respectively given at 2 weeks and 4 weeks after radical tumor resection. In 2nd week after surgery, 33 cases of them accepted Roferon-A treatment for 1 week. Seventy-two patients were followed up over 3 years. Effect of Roferon-A combined with HACE and PVC on postoperative recurrence rate was compared with that of HACE and PVC. Changes of T cell subsets in peripheral blood were examined with labeled monoclonal antibodies before and after hepatectomy or using interferon. Forty cholecystolithiasis patients received cholecystectomy were used as the controls.</p><p><b>RESULTS</b>CD(3)(+) and CD(4)(+) cells in peripheral blood were reduced in patients with HCC. After hepatectomy, they declined further with decrease in CD(4)(+)/CD(8)(+) ratio. The results returned to pre-operative level at the end of 4th week after surgery. The CD(3)(+), CD(4)(+) cells and the CD(4)(+)/CD(8)(+) ratio increased remarkably following the use of Roferon-A. The 1-, 2- and 3-year recurrence rates of patients treated with HACE, PVC and Roferon-A in combination were 0%, 6.2% and 15.6%, respectively, while those treated with HACE and PVC were 5.0%, 12.5% and 27.5%, respectively.</p><p><b>CONCLUSION</b>Patients with HCC suffer from marked immuno-suppression which became ever more severe after hepatectomy, combined use of HACE, PVC and Roferon-A is superior to only HACE and PVC by decreasing the recurrence rate.</p>