T cells isolated from B cell-rich tumours expressed more mRNA for Tcf7 and Tcf1 (involved in maintenance of stem-like T cell population), Il7r and Sell (encoding CD62L) as well as lower levels of transcripts for granzyme-encoding genes and Ptpn22 (54), a negative regulator of TCR signalling (4). The gene discussed is SELL; the disease is neoplasm.