Characterization of human non-small cell lung cancer (NSCLC) cell lines for expression of MHC, co-stimulatory molecules and tumor-associated antigens

A panel of 31 long-term non-small cell lung cancer (NSCLC) cell lines was e xamined for the expression of protein and/or mRNA transcripts for 11 distin ct immune response related molecules or tumor associated antigens (TAA). To assess whether cytokine stimulation might up-regulate expression of the ge nes of interest, cells were cultured in 500 U/ml of gamma-interferon (gamma -IFN) for 48-72 h prior to analysis. Major histocompatibility complex (MHC ) Class I antigens were detected by indirect immunofluorescence and were co nstitutively expressed on all of the cell lines. The average of the mean fl uorescence intensity (MFI) measured 222 +/- 22. gamma -IFN stimulation prod uced a significant increase to 482 +/- 36. For MHC Class II only 7/31 cell lines (23%) exhibited constitutive expression, while gamma -IFN treatment h ad a dramatic effect and yielded 18/31 (58%) positive cell lines. The co-st imulatory molecules CD80 and CD86 were examined by direct immunofluorescenc e for cell surface expression and RT-PCR amplification for mRNA. CD80 prote in was not detected at all, while an insignificant percentage of cells were positive (mean 2%) for CD86 in all cell lines tested. gamma -IFN had no ap parent effect on CD80 or CD86 protein expression. Constitutive CD80 or CD86 mRNA levels were observed in 45 and 61% of the NSCLC lines, respectively. These percentages increased to 77% and 90% with gamma -IFN. Cell surface ph enotypic analysis for TAA revealed positive populations in 28/31 cell lines (90%) for Her-2/neu, 18/31 (58%) for CEA and 8/31 (26%) for GD-2, with gam ma -IFN having no effect. After gamma -IFN stimulation, RT-PCR amplificatio n for Mage-1, -2, -3 and WT-1 detected mRNA in 33%, 33%, 44% and 70% of the cell lines, respectively. Overall, gamma -IFN stimulation led to the up-re gulation of MHC Class I molecules and class 11 molecules as well as CD80 an d CD86 mRNA transcripts. This survey represents the first comprehensive ana lysis of NSCLC cell lines for a variety of molecules that could play an imp ortant role in the generation of an NSCLC anti-tumor CD8 + cytotoxic T lymp hocyte (CTL) response. (C) 2001 Elsevier Science Ireland Ltd. All rights re served.