Identification of HCC-22-5 tumor-associated antigen and antibody response in patients.
BACKGROUND
Serological identification of antigens by recombinant expression cloning (SEREX) is a promising method used to analyze tumor-associated antigen (TAA). Nineteen primary HCC-associated antigens have been found from a HCC cDNA library using autogenous serum by the SEREX approach. We searched for HCC-associated antigens and applied them to HCC diagnosis.


METHODS
Nine of 19 primaries HCC-associated antigens identified by SEREX method were tested their immune response again with distinct allogeneic sera. One of the screened HCC-associated antigens, HCC-22-5 was recombined and expressed and made the frequency analysis of its seropositivity in various patients using the methods of Western-blot and ELISA.


RESULTS
SEREX analysis showed that 9 primary HCC-associated antigens had high-titered IgG antibody in the majority of HCC patients. Western-Blot method confirmed that 3/7 HCC patients had antibodies against HCC-22-5, which demonstrated that expressed HCC-22-5 antigen had the character of antigen. Sera samples from 341 patients and 80 normal individuals have been tested for autoantibodies against HCC-22-5 by ELISA method. The results found that 51/128 of HCC, 11/76 of chronic hepatitis, 11/22 of liver cirrhosis and 8/54 of nasopharynx cancer patients had antibodies against HCC-22-5. No antibody response to HCC-22-5 had been found in the sera of 7 lung cancers, 54 gastric-intestine patients and 80 normal individuals. The groups of HCC and liver cirrhosis had higher antibody positive rate than that of other groups (p<0.05). In the HCC sera with alpha-fetoprotein (AFP) negative, the positive rate of HCC-22-5 was as high as 78.9%.


CONCLUSIONS
HCC-22-5 can be used for HCC serologic screening, especially for the patients with AFP negative.
Zhou
Su-Fang
SF
The School of Pre-clinical Sciences, Guangxi Medical University, 22 Shuangrong Road, Nanning 530021, China. zfs2000@yahoo.com.cn
Xie
Xiao-Xun
XX
Bin
Ye-Hong
YH
Lan
Lin
L
Chen
Fang
F
Luo
Guo-Rong
GR
D000595:Amino Acid Sequence; D000917:Antibody Formation / Q000276:immunology*; D000951:Antigens, Neoplasm / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D001483:Base Sequence; D015153:Blotting, Western; D006528:Carcinoma, Hepatocellular / Q000097:blood / Q000235:genetics / Q000276:immunology*; D002352:Carrier Proteins / Q000235:genetics; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D006521:Hepatitis, Chronic / Q000097:blood / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D008103:Liver Cirrhosis / Q000097:blood / Q000276:immunology; D008113:Liver Neoplasms / Q000097:blood / Q000235:genetics / Q000276:immunology*; D058619:Maltose-Binding Proteins; D008969:Molecular Sequence Data; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D017422:Sequence Analysis, DNA
D000951:Antigens, Neoplasm; D002352:Carrier Proteins; D018076:DNA, Complementary; C510802:HCC-22-5 antigen, human; D007074:Immunoglobulin G; D058619:Maltose-Binding Proteins; D011993:Recombinant Fusion Proteins