CD107a expression in patients with HAM/TSP and in healthy HTLV-1 carriers after coculture with immunodominant Tax peptide. In the righthand panel, PVL denotes proviral load: here, CD107 expression was measured in samples from healthy HLTV-1 carriers whose proviral loads were in the same range as those of patients with HAM/TSP. See the complete figure in the article beginning on page 2411.