Table 3.

Summary of mesothelin-specific T-cell responses in the HLA-A1+/HLA-A2+/HLA-A3+ patients treated with the vaccine alone or in sequence with cyclophosphamide

Patient/HLAMesothelin-specific T cells/106 CD8 T cells
Survival (mo)
PreVaccine 3Vaccine 6Follow-upFollow-up 2Follow-up 3
Cohort A (patients given immunotherapy alone)
Cohort B (patients given immunotherapy + Cytoxan)
  • NOTE: The ELISPOT assay was used to determine the number of mesothelin-specific CD8+ T cells specific for the HLA-A1+ epitope, MesoA1(20-28), HLA-A2+ mesothelin epitope MesoA2(530-539), or the HLA-A3 mesothelin(225-234) epitope. All time points for each patient were assayed simultaneously in six replicates and reported as the mean number of mesothelin-specific CD8+ T cells per 106 total CD8+ T cells. Background spots were determined using a negative peptide control known to bind to HLA-A1 HIV-Nef(73-87) (QVPLRPMTY), HLA-A2 HIV-gag(77-85) (SLYNTVATL), and HLA-A3 HIV-1NEF(94-102) (QVPLRPMTYK6). Background spots ranged from 0 to 10 spots per well. A CEF pool was used as a positive control. The CEF pool contains epitopes from cytomegalovirus, EBV, and influenza A virus proteins that bind to most HLA class I molecules. The CEF pool was obtained from NIH AIDS Research and Reference Reagent Program, Division of AIDS, National Institute of Allergy and Infectious Diseases, NIH (CEF control peptide pool, 9808). Positive control spots ranged from 40 to 1,300 per well.

    Abbreviations: Pre, pretreatment 1; treatment cycle 1, posttreatment 1; vaccine 3, posttreatment 3; vaccine 6, posttreatment 6; NA, not available due to patient progression.