RESUMO
We have identified an antigen recognized by cytolytic T lymphocytes (CTL) on the autologous tumor cells of a nonsmall cell lung cancer patient. The antigenic peptide, presented by HLA-B*5201 molecules, was encoded by a mutated sequence in the gene coding for the C subunit of transcription factor NF-Y. The mutation was present in the tumor sample from which the cell line was derived, and appeared to be unique to the tumor of this patient. In a lymph node draining the tumor, precursors of CTL recognizing the autologous tumor cells were detected at a frequency of about 1/30,000 of the CD8 cells, and 85% of them recognized the mutated NF-YC peptide, suggesting that the patient mounted a T cell response against this antigen. These results strengthened the notion that unique tumor-specific antigens are highly represented not only in melanoma but also in other types of tumors, like nonsmall cell lung cancer.
