Optimized serological isolation of lung-cancer-associated antigens from a yeast surface-expressed cDNA library.
The technique of serological analysis of antigens by recombinant cDNA expression library (SEREX) uses autologous patient sera as a screening probe to isolate tumor-associated antigens for various tumor types. Isolation of tumor-associated antigens that are specifically reactive with patient sera, but not with normal sera, is important to avoid false-positive and autoimmunogenic antigens for the cancer immunotherapy. Here, we describe a selection methodology to isolate patient sera-specific antigens from a yeast surface-expressed cDNA library constructed from 15 patient lung tissues with non-small cell lung cancer (NSCLC). Several rounds of positive selection using patient sera alone as a screening probe isolated clones exhibiting comparable reactivity with both patient and normal sera. However, the combination of negative selection with allogeneic normal sera to remove antigens reactive with normal sera and subsequent positive selection with patient sera efficiently enriched patient sera-specific antigens. Using the selection methodology described here, we isolated 3 known and 5 unknown proteins, which have not been isolated previously, but and potentially associated with NSCLC.
Department of Molecular Science and Technology, Ajou University, Suwon 443-749, Korea.
Min-Soo
MS
Kim
Hye Young
HY
Choi
Yong Soo
YS
Choi
Jhingook
J
Kim
Yong-Sung
YS
Kim
D000368:Aged; D000951:Antigens, Neoplasm / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D002289:Carcinoma, Non-Small-Cell Lung / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry; D015723:Gene Library; D006801:Humans; D008175:Lung Neoplasms / Q000276:immunology*; D008280:Magnetics; D008297:Male; D008875:Middle Aged; D012441:Saccharomyces cerevisiae / Q000235:genetics*
D000951:Antigens, Neoplasm