The effective and specific isolation of antibodies from human serum by using thiophilic paramagnetic polymer beads.

A rapid and effective method to specifically isolate immunoglobulin G (IgG) from human serum by thiophilic paramagnetic polymer beads was developed. The thiophilic paramagnetic beads were synthesized with vinyl acetate and divinylbenzene by microsuspension polymerization in the presence of magnetite nanoparticles. Divinylsulfone and 2-mercapto-benzothiazole were subsequently used to modify the surface of these beads, resulting in thiophilic particles that exhibited a high specificity to the antibodies in serum at low salt concentration. The adsorbed IgG was eluted by 0.8M KCl and 72% of the IgG in the serum was recovered. The purity of the isolated IgG reached 98.4% and the bioactivity was fully maintained (>99%). The high efficiency, mild conditions and simplicity make this technology suitable for the economic purification of antibodies in a large scale.

Detection of HBV, PCNA and GST-pi in hepatocellular carcinoma and chronic liver diseases.

AIM: To investigate the change of HBV DNA, PCNA and GST-pi in chronic liver disease and hepatocellular carcinoma (HCC). METHODS: Hepatitis B surface antigen (HBsAg), proliferating cell nuclear antigen (PCNA) and glutathione S-transferases (GST-pi) were detected by immunohistochemical staining and HBV DNA was detected by in situ hybridization (ISH) in formalin-fixed and paraffin-embedded sections with a total of 111 specimens of chronic hepatitis, liver cirrhosis, paratumorous tissue, HCC and normal liver tissue. RESULTS: The positive rates of HBsAg and HBVDNA were 62.5 %(15/24) and 75.0 %(12/16) in chronic hepatitis, 64.0 %(16/25) and 83.3 %(15/18) in liver cirrhosis, 72.7 %(16/22) and 85.7 %(12/14) in the paratumorous tissu and 45.0 %(14/31) and 64.3 %(9/14) in HCC. The positive HBVDNA granules in chronic hepatitis, liver cirrhosis and the paratumorous tissue were more intense than that in HCC. The positive rates of PCNA and GST-pi were 34.8 %(8/23) and 25.0 %(4/16) in chronic hepatitis, 73.7 %(14/19) and 17.6 %(3/17) in liver cirrhosis, 86.7 %(13/15) and 53.3 %(8/15) in the paratumorous tissue, 100 %(15/15) and 60.0 %(9/15) in HCC, respectively, and the positive rate of GST-pi in the paratumorous tissue was significantly higher than that in the liver cirrhosis without tumor (P<0.05), but same as that in HCC (P>0.05). CONCLUSION: The HBV infection may increase expression of PCNA and GST-pi. The paratumor cirrhosis may be a sequential lesion of precancerous cirrhosis around HCC.