Recognition of naturally processed HTLV-1 Tax protein derived from HAM patient's PBMC. A, HTLV-1 Tax protein content was evaluated by Western blot analysis using antibody Lt-4 specific for HTLV-1 Tax to determine whether the HTLV-1 Tax protein was present i... Recognition of naturally processed HTLV-1 Tax protein derived from HAM patient's PBMC. A, HTLV-1 Tax protein content was evaluated by Western blot analysis using antibody Lt-4 specific for HTLV-1 Tax to determine whether the HTLV-1 Tax protein was present in PBMCs from two HAM patients (HAM1 and HAM2). The HTLV-1 Tax protein was detected in cell lysates prepared from both HAM patient's PBMC and MT2 cells (positive control HTLV-1+ lymphoma) but not in PBMC from a healthy individual. B and C, the peptide Tax191-205-specific HTL line 9B and peptide Tax305-319-reactive HTL clone 25 recognized the lysates prepared from HAM patient's PBMC and the response was inhibited by anti-DR mAb L243 at 10 μg/mL. Results correspond to triplicate samples. Columns without bars had SD <10% the value of the mean. Representative of two experiments that were done with the same samples. Hiroya Kobayashi et al. Clin Cancer Res 2006;12:3814-3822 ©2006 by American Association for Cancer Research